USRE45869E1 - Slurry dewatering and conversion of biosolids to a renewable fuel - Google Patents

Slurry dewatering and conversion of biosolids to a renewable fuel Download PDF

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USRE45869E1
USRE45869E1 US14/563,120 US201414563120A USRE45869E US RE45869 E1 USRE45869 E1 US RE45869E1 US 201414563120 A US201414563120 A US 201414563120A US RE45869 E USRE45869 E US RE45869E
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biosolids
slurry
char
water
fuel
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Norman L. Dickinson
Kevin M. Bolin
Brian Dooley
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SGC Advisors LLC
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    • CCHEMISTRY; METALLURGY
    • C10PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10GCRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
    • C10G1/00Production of liquid hydrocarbon mixtures from oil-shale, oil-sand, or non-melting solid carbonaceous or similar materials, e.g. wood, coal
    • C10G1/02Production of liquid hydrocarbon mixtures from oil-shale, oil-sand, or non-melting solid carbonaceous or similar materials, e.g. wood, coal by distillation
    • CCHEMISTRY; METALLURGY
    • C10PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10LFUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G, C10K; LIQUEFIED PETROLEUM GAS; ADDING MATERIALS TO FUELS OR FIRES TO REDUCE SMOKE OR UNDESIRABLE DEPOSITS OR TO FACILITATE SOOT REMOVAL; FIRELIGHTERS
    • C10L5/00Solid fuels
    • C10L5/40Solid fuels essentially based on materials of non-mineral origin
    • C10L5/42Solid fuels essentially based on materials of non-mineral origin on animal substances or products obtained therefrom, e.g. manure
    • CCHEMISTRY; METALLURGY
    • C10PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10GCRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
    • C10G1/00Production of liquid hydrocarbon mixtures from oil-shale, oil-sand, or non-melting solid carbonaceous or similar materials, e.g. wood, coal
    • CCHEMISTRY; METALLURGY
    • C10PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10LFUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G, C10K; LIQUEFIED PETROLEUM GAS; ADDING MATERIALS TO FUELS OR FIRES TO REDUCE SMOKE OR UNDESIRABLE DEPOSITS OR TO FACILITATE SOOT REMOVAL; FIRELIGHTERS
    • C10L5/00Solid fuels
    • C10L5/40Solid fuels essentially based on materials of non-mineral origin
    • C10L5/46Solid fuels essentially based on materials of non-mineral origin on sewage, house, or town refuse
    • CCHEMISTRY; METALLURGY
    • C10PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10LFUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G, C10K; LIQUEFIED PETROLEUM GAS; ADDING MATERIALS TO FUELS OR FIRES TO REDUCE SMOKE OR UNDESIRABLE DEPOSITS OR TO FACILITATE SOOT REMOVAL; FIRELIGHTERS
    • C10L9/00Treating solid fuels to improve their combustion
    • C10L9/08Treating solid fuels to improve their combustion by heat treatments, e.g. calcining
    • C10L9/086Hydrothermal carbonization
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23GCREMATION FURNACES; CONSUMING WASTE PRODUCTS BY COMBUSTION
    • F23G7/00Incinerators or other apparatus for consuming industrial waste, e.g. chemicals
    • F23G7/001Incinerators or other apparatus for consuming industrial waste, e.g. chemicals for sludges or waste products from water treatment installations
    • CCHEMISTRY; METALLURGY
    • C02TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02FTREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F11/00Treatment of sludge; Devices therefor
    • C02F11/10Treatment of sludge; Devices therefor by pyrolysis
    • CCHEMISTRY; METALLURGY
    • C02TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02FTREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2103/00Nature of the water, waste water, sewage or sludge to be treated
    • C02F2103/001Runoff or storm water
    • CCHEMISTRY; METALLURGY
    • C10PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10GCRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
    • C10G2300/00Aspects relating to hydrocarbon processing covered by groups C10G1/00 - C10G99/00
    • C10G2300/10Feedstock materials
    • C10G2300/1003Waste materials
    • CCHEMISTRY; METALLURGY
    • C10PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10GCRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
    • C10G2300/00Aspects relating to hydrocarbon processing covered by groups C10G1/00 - C10G99/00
    • C10G2300/10Feedstock materials
    • C10G2300/1011Biomass
    • CCHEMISTRY; METALLURGY
    • C10PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10GCRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
    • C10G2300/00Aspects relating to hydrocarbon processing covered by groups C10G1/00 - C10G99/00
    • C10G2300/40Characteristics of the process deviating from typical ways of processing
    • C10G2300/4043Limiting CO2 emissions
    • CCHEMISTRY; METALLURGY
    • C10PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10GCRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
    • C10G2300/00Aspects relating to hydrocarbon processing covered by groups C10G1/00 - C10G99/00
    • C10G2300/40Characteristics of the process deviating from typical ways of processing
    • C10G2300/4081Recycling aspects
    • CCHEMISTRY; METALLURGY
    • C10PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10GCRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
    • C10G2300/00Aspects relating to hydrocarbon processing covered by groups C10G1/00 - C10G99/00
    • C10G2300/80Additives
    • C10G2300/805Water
    • CCHEMISTRY; METALLURGY
    • C10PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10GCRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
    • C10G2300/00Aspects relating to hydrocarbon processing covered by groups C10G1/00 - C10G99/00
    • C10G2300/80Additives
    • C10G2300/805Water
    • C10G2300/807Steam
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02EREDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E20/00Combustion technologies with mitigation potential
    • Y02E20/16Combined cycle power plant [CCPP], or combined cycle gas turbine [CCGT]
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02EREDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E50/00Technologies for the production of fuel of non-fossil origin
    • Y02E50/10Biofuels, e.g. bio-diesel
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02EREDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E50/00Technologies for the production of fuel of non-fossil origin
    • Y02E50/30Fuel from waste, e.g. synthetic alcohol or diesel
    • Y02E50/343
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02PCLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P30/00Technologies relating to oil refining and petrochemical industry
    • Y02P30/20Technologies relating to oil refining and petrochemical industry using bio-feedstock
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02PCLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P30/00Technologies relating to oil refining and petrochemical industry
    • Y02P30/40Ethylene production
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02WCLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
    • Y02W10/00Technologies for wastewater treatment
    • Y02W10/30Wastewater or sewage treatment systems using renewable energies
    • Y02W10/37Wastewater or sewage treatment systems using renewable energies using solar energy
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02WCLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
    • Y02W30/00Technologies for solid waste management
    • Y02W30/40Bio-organic fraction processing; Production of fertilisers from the organic fraction of waste or refuse
    • Y02W30/47

Definitions

  • biosolids Sludge from sewage and wastewater treatment plants, and the biosolids it contains, represents a serious disposal problem.
  • the Water Environment Federation (WEF) formally recognized the term “biosolids” in 1991, and it is now in common use throughout the world.
  • the WEF defines “biosolids” as the soil-like residue of materials removed from sewage during the wastewater treatment process. During treatment, bacteria and other tiny organisms break sewage down into simpler and more stable forms of organic matter. The organic matter, combined with bacterial cell masses, settles out to form biosolids. According to USEPA, biosolids that meet treatment and pollutant content criteria “can be safely recycled and applied as fertilizer to sustainably improve and maintain productive soils and stimulate plant growth”.
  • the sludge is a mixture of biosolids (comprised primarily of dead organic cells which are a by-product of treating sewage and wastewater so that it can be released into open waters) and varying amounts of free water. Free water can be at least partially removed by mechanical dewatering methods. In addition to the free water, the biosolids contain cell-bound water, which can make up as much as 80% of the volume of biosolids and is impossible to remove by mechanical dewatering methods. The large amounts of water contained in such sludge give it a highly negative heat value which makes the cost of incinerating it prohibitive because large amounts of costly fuel would be required to drive off the cell-bound water.
  • such sludge is presently used as landfill or as a fertilizer that can be spread over land, because sewage sludge frequently contains nitrogen and phosphor, for example.
  • the sludge also contains harmful substances, generates undesirable odors, and can lead to serious contamination of the soil or the landfill from, amongst others, heavy metals.
  • Sewage sludge is a mass or agglomeration of dead organic cells and other solids, called biosolids, which are mixed with varying amounts of water of correspondingly varying viscosity. Irrespective of the degree to which the mass of biosolids is mechanically dewatered, the remaining mass of biosolids typically contains about 80% water, because much of the water is bound inside the dead cells, giving the biosolids mass a negative heating value, thereby making biosolids effectively useless for purposes of extracting heat value from them.
  • biosolids still are disposed of in landfills or by spreading them on agricultural land as a fertilizer that supplies nitrogen and phosphorus.
  • biosolids also may contain live viruses and pathogens and toxic heavy metals, inspiring heated opposition from environmental interests, while their high water content drastically increases the cost of transporting them to a point of use.
  • the raw biosolids are heated following their discharge from the sewage treatment plant to rupture the cells, thereby releasing the large quantities of cell-bound water.
  • the temperature is sufficiently high so that the cell structure is destroyed and carbon dioxide is split off to lower the oxygen content of the biosolids. This results in the formation of char that is not hydrophilic and can be efficiently dewatered and/or dried. This char is a viable renewable fuel.
  • biomass such as untreated yard and crop waste, etc.
  • non-renewable hydrophilic fuels can be so processed to further augment the energy that can be extracted from biosolids in accordance with the invention.
  • Green Power There is a growing wave of public support for renewable energy popularly called “Green Power”.
  • WRI World Resources Institute
  • MW Megawatts
  • Biomass has long been used as a renewable energy source. For example, wood and forestry, as well as agricultural, by-products have been used as fuels for centuries by mechanically firing them in furnaces and boilers with high excess air and low efficiency.
  • the National Renewable Energy Laboratory (NREL) defines biomass as: “organic matter available on a renewable basis. Biomass includes forest and mill residues, agricultural crops and wastes, wood and wood wastes, animal wastes, livestock operation residues, aquatic plants, fast growing trees and plants and municipal and industrial wastes.” According to The Sandia National Laboratory's Combustion Research Facility (CRF), combustion is involved in 85% of the world's energy use. If biomass is to make a meaningful contribution to renewable energy, it will be, directly or indirectly, as a fuel.
  • CRF National Laboratory's Combustion Research Facility
  • biosolids Sewage sludge, and the large amounts of biosolids it contains, with their cell-bound water, has not previously been considered an energy source. Due to their large bound water content, biosolids have a negative fuel value and cannot be incinerated unless heated with expensive fuel that must be purchased. Such an incineration of biosolids may be desirable to avoid having to spread them on land, thereby eliminating or at least reducing possible environmental contamination, but at a very substantial cost, namely the additional heat that must come from the fuels to incinerate them.
  • the solids concentration in biosolids still only ranges from about 14-30%, and is typically no more than about 20%, which means that every ton of biosolids, treated and dewatered in accordance with the prior art, is accompanied by about four tons of water, the bulk of which is bound in the dead cells.
  • the cost of shipping the inert water limits the distance it can be moved from its source, usually a wastewater treatment plant (WWTP). These factors give biosolids a negative value. As a result, the WWTP must pay to have someone dispose of the biosolids. Such a payment is often called a “tipping fee”.
  • a typical WWTP may employ centrifuges, belt presses, rotary presses or other processes to physically force the water from the biosolids.
  • a polymer and other chemicals may be added to assist in dewatering. Nevertheless, such mechanical dewatering methods used by WWTPs are inefficient and costly and incapable of appreciably reducing the amount of water bound in the cells of the biosolids.
  • the U.S. Environmental Protection Agency grades biosolids according to regulation “40 CFR Part 503” as Class A and Class B.
  • This regulation concerns primarily the application of biosolids to agricultural land, to which there is vocal and growing environmental opposition.
  • environmentalists condemn the use of biosolids as a fertilizer because of their content of living disease-causing organisms (pathogens and viruses) and heavy metals (such as lead, mercury, cadmium, zinc and nickel), as well as their damage to groundwater quality.
  • environmentalists raise concerns about “quality of life” issues, such as insects and odors, associated with biosolids.
  • land application of Class B biosolids is banned in a number of counties, and more counties and states are expected to follow. In one case, where 70% of the biosolids were Class B, the banning of land application in adjacent counties nearly doubled the tipping fee from about $125 per dry ton to about $210-$235.
  • biosolids make their incineration difficult for many industries.
  • the cement industry is reputed to be the world's third largest energy user. It requires the equivalent of about 470 pounds of coal to make each ton of cement.
  • 15 cement plants in the U.S. burn fuel-quality hazardous waste, and about 35 other plants use scrap tires to supplement fossil fuel.
  • a growing method of disposing of biosolids is to incinerate them in cement kilns. Since their net fuel value is negative, this practice is only viable because of the revenue received by the kiln operator, for example, from the tipping fee, since additional fuel, such as coal, must be fired to eliminate the water bound in biosolids.
  • certain elements contained in biosolids such as chlorine, phosphorus, sodium and potassium, are not desired because they adversely affect the quality of the cement.
  • the current invention provides a method to dispose of biosolids while concurrently producing an economically more viable renewable fuel.
  • the biosolids conversion to a useable fuel in according with the present invention can be combined with extracting energy from other sources such as biomass.
  • the present invention provides a method and system to convert biosolids, alone or with biomass, into a viable renewable fuel in an environmentally benign manner.
  • biosolids are composed primarily of dead cells which have cell-bound water.
  • a heating of a slurry or sludge containing biosolids to a first, relatively lower, temperature causes the biosolids cells to rupture, which liberates the water bound inside the cells and thereby converts the biosolids from a substance which cannot practically be dewatered to a new fuel from which the water can be readily removed mechanically.
  • the further heating of the biosolids additionally splits off carbon dioxide, thereby lowering the oxygen content of the biosolids and converting the biosolids into char.
  • the char Once dewatered, the char has a positive heating value and can be used directly as a fuel, thereby releasing the heat energy that was previously inaccessibly bound in the biosolids.
  • the present invention provides a method to produce a viable, renewable fuel from biosolids by converting the biosolids into a relatively dry, combustible material.
  • the process can be integrated with the existing infrastructure of the WWTP. Since the treated biosolids have substantially no bound water, freed water from the cells can be returned to the WWTP. The remaining cell materials become much less hydrophilic, which gives them a positive heating value and allows them to be shipped to the desired destination at a much reduced cost. If the WWTP is equipped with an anaerobic digestion stage, the gas produced can support the fluid deoxidation with fuel used in its operation.
  • Biosolids char is a new player on the energy scene and is a low-cost, renewable fuel for many energy-consuming industries.
  • biosolids char is most productively used where its energy content is utilized.
  • the method and system of the present invention is used in conjunction with a cement kiln to increase the thermal efficiency of the cement kiln and cement manufacture, while disposing of biosolids that would otherwise constitute undesirable waste.
  • the inert material found in the biosolids can become a part of the product. Therefore, not only is the heating value in biosolids utilized, but the inerts leave no negative by-products from this configuration.
  • biosolids are produced as a viscous slurry, little preparation is required, except blending for uniformity. Following heating of the biosolids slurry under pressure to a temperature at which the cell walls rupture, the further heating of the biosolids results in a significant molecular rearrangement of the cells, splitting off of a substantial proportion of its oxygen as carbon dioxide, which carbonizes organic substances and yields so-called char that is readily incinerated.
  • the temperature necessary for this molecular rearrangement varies but is typically between 177° C. and 315° C. (350° F. and 600° F.).
  • the aggressively hydrolyzing conditions free anions to dissolve in the aqueous phase.
  • Previously bound cations, such as sodium and potassium, are likewise made accessible to aqueous dissolution and subsequent removal and/or disposal.
  • Cement kiln and incinerator facilities may prefer for the char to be dewatered to a maximum extent, resulting in the delivery and charging of a wet solid “char” containing only about 40% to 50% water, which is about one-fifteenth of that found in the raw biosolids.
  • transport and handling considerations may cause such facilities to prefer char which has been dried and compacted or pelletized.
  • the present invention has the capability to deliver char in either form.
  • biosolids char produced with this invention provides a fuel that is useful to a variety of other fuel-consuming industries, including blast furnaces, foundries, utility boilers, the power industry, the paper industry, and other fossil fuel-utilizing industries.
  • the present invention contemplates a green power station where biosolids char is charged to a pulverized fuel or fluidized bed combustor to generate steam, or to a gasifier feeding clean fuel gas to an integrated gas-fired gas turbine combined cycle.
  • the char produced by the present invention can be the raw material for hydrogen fuel cells through partial oxidation to a fuel gas (largely carbon monoxide and hydrogen), followed by the water gas shift and the separation of carbon dioxide, as practiced in synthetic ammonia technology. It can be “refined” into liquid fuels by adaptations of “catalytic cracking”, “delayed coking” and “hydrocracking”, patterned after the established processes well known to the petroleum refining industry.
  • While the present invention is directed to the economic and ecologically sound disposition of biosolids, it can be combined with appropriately treated other substances, primarily biomass that requires disposal, including, but not limited to, paper mill sludge, food waste, agricultural wastes, hog manure, chicken litter, cow manure, rice hulls, bagasse, green waste, municipal solid waste, medical waste, paper waste, wood and wood waste, palm oil residue, refuse derived fuels, Kraft Mill black liquor, and short rotation energy crops, as well as hydrophilic non-renewable fuels such as low-rank coals.
  • biomass primarily biomass that requires disposal, including, but not limited to, paper mill sludge, food waste, agricultural wastes, hog manure, chicken litter, cow manure, rice hulls, bagasse, green waste, municipal solid waste, medical waste, paper waste, wood and wood waste, palm oil residue, refuse derived fuels, Kraft Mill black liquor, and short rotation energy crops, as well as hydrophilic non-renewable fuels such as low-rank coals.
  • the present invention relates to a process of converting biosolids into an economically viable fuel by applying sufficient pressure to the biosolids to maintain liquidity, heating the pressurized biosolids to a sufficient temperature to rupture cells and then to evolve carbon dioxide, depressurizing the resulting char slurry, separating the carbon dioxide from the char slurry, and removing at least a portion of the aqueous phase from the char slurry to provide an at least partially dewatered char product for further use.
  • the invention relates to reacting the dewatered char product with a gas comprising oxygen to thereby convert its fuel value into thermal energy and using the thermal energy or incinerating the fuel.
  • the present invention provides an environmentally acceptable disposition of biosolids, as well as energy for various energy consumers, such as cement kilns and electric power plants.
  • the present invention provides: (a) a method to increase the availability and environmental acceptability of renewable fuels; (b) a method to minimize the quantity of wastes to be landfilled; (c) a process to reduce the moisture (water) content of waste going to landfill; (d) a process to raise the softening point of renewable fuel ash to reduce fouling and slagging; (e) a method of converting a non-uniform solid fuel, such as agricultural and forestry waste and/or paper mill sludge, into a uniform fuel; (f) a method to convert a bulky fuel into a fuel that is compact and easy to store and transport; (g) a process to convert a perishable fuel into a sterile fuel that is storable without deterioration; (h) a method to provide an economical means of cofiring an otherwise non-compliant fuel;
  • the present invention provides a method for the disposal of sludge generated at sewage and wastewater treatment plants in an economical and environmentally benign manner.
  • the method is economically benign because the end product is ash that is free of odors, as well as harmful substances such as viruses or pathogens, and the ash has a small volume and is readily disposed of.
  • the method is further economically viable because at the front end it benefits from the willingness of treatment plant operators to pay a tipping fee in order to dispose of the difficult-to-handle sewage sludge, and further because, at the other end of the cycle, the sludge will have been converted into a fuel with a positive heating value that can be used to generate further revenue or other items of value in the form of payments for the generated heat energy or, for example, trading the extracted heat for credits, desired products and the like.
  • FIG. 1 is a schematic flow diagram illustrating the process of the present invention for converting biosolids into a high energy density slurry or dry solid fuel as a renewable energy source;
  • FIG. 1A is a schematic flow diagram similar to FIG. 1 illustrating another process of the present invention for converting biosolids into a high energy density slurry or dry solid fuel as a renewable energy source;
  • FIG. 2 is a flow diagram in which the process of the present invention is used in a wastewater treatment plant
  • FIG. 3 is a flow diagram in which the process of the present invention is used in the operation of a cement kiln
  • FIG. 4 is a flow diagram in which the process of the present invention is employed in the operation of a thermal power station using additional fuels, such as low-rank coals; and
  • FIG. 5 is a flow diagram in which the process of the present invention is combined with a thermal dryer and used in a cement kiln.
  • FIG. 1 illustrates the conversion of biosolids to a viable renewable fuel.
  • Biosolids may be delivered as sludge via a pipeline 107 from an adjacent wastewater or sewage treatment plant (WWTP) to a raw feed tank 106 .
  • WWTP wastewater or sewage treatment plant
  • biosolids may be delivered by a truck 108 and pumped by a sludge pump 109 via a line 110 to the tank 106 .
  • the raw feed tank 106 can receive biosolids from multiple sources and be utilized as a mixing vessel whereby more dilute biosolids are mixed with thicker, more viscous biosolids to render a more pumpable feed.
  • a commingling and slurrying facility 104 can also be utilized for this purpose.
  • raw feed tank 106 or comminuting commingling and slurrying facility 104 can be the points whereby polymer is added to reduce the water content of the biosolids slurry or, alternatively, where water is added if the viscosity of the slurry is an issue.
  • Heat may be added to the tank 106 to enhance the viscosity of the biosolids.
  • a shearing or grinding step may be added, for instance between the raw feed tank 106 and a pumping device 111 . This shearing or grinding will lower viscosity as well as achieve the particle size uniformity necessary for optimal operation of a pressure let-down valve 116 . Addition of heat, shearing and grinding will also enhance the performance of the pumping device 111 and allow a higher solids content material into the system.
  • a screening device is added to remove large particle-size items to enhance the performance of any grinding, the pumping device 111 and/or the pressure let-down valve 116 .
  • the screening device may be placed between the raw feed tank 106 and the pumping device 111 .
  • the raw feed tank 106 or a similar device can be used to add a chelating agent or other suitable chemical to remove phosphorus or other elements found in the biosolids.
  • the biosolids slurry is pumped to a pressure that will keep the water in the slurry in liquid phase during subsequent heating operations.
  • the slurry is at a pressure ranging from about 400 to 1200 psi.
  • the pressure of the slurry is between about 250 to 1600 psi.
  • Care must be exercised to provide a pumping device 111 with an adequate net pump suction head (NPSH), either hydraulically or by mechanical assistance, as with a screw conveyor, considering that the slurry may be very viscous and may carry dissolved gases.
  • NPSH net pump suction head
  • An alternative (not shown), for reducing the service of the pumping device 111 is the addition of booster pumps in the process anywhere between the pumping device 111 and the let-down valve 116 .
  • a further alternative (not shown) for reducing the service of the pumping device 111 is the addition of freed water or reacted slurry before the pumping device 111 .
  • the biosolids slurry is pumped through heat exchangers 112 and 113 before passing to a reactor 114 . While passing through the heat exchanger 112 the slurry is heated by exchange with hot liquid heat transfer fluid (HTF), such as Therminol 59. In another embodiment (not shown), the slurry may be heated via heat exchange with steam, either directly or indirectly.
  • the outlet temperature of the slurry leaving heat exchanger 112 may range from about 150° C. to 315° C. (300° F. to 600° F.), and is preferably between about 200° C. to 260° C. (400° F. to 500° F.).
  • the slurry While passing through the heat exchanger 113 , the slurry is further heated to the desired temperature at which the biosolids cell walls will rupture and to liberate water bound in the cells.
  • the temperature is further preferably set so that the other constituents of the biosolids cells are carbonized to convert these constituents to char by heat exchange with hot liquid HTF.
  • the condensing vapor of a vaporizable HTF such as Therminol VP-1, is used to heat the slurry to the desired temperature. In one embodiment, this temperature is between about 200° C. to 260° C. (400° F. to 500° F.). In another embodiment, the temperature is between about 150° C. to 260° C. (300° F. to 500° F.). In still another embodiment, the temperature is between about 260° C. to 350° C. (500° F. to 650° F.).
  • each may comprise two or more shells.
  • the shells may be in parallel or in series.
  • the heat exchangers 112 and 113 are arranged in a series such that the biosolids slurry passes through heat exchanger 112 prior to heat exchanger 113 .
  • the reactor 114 (which may comprise one or more reactors in parallel or series) provides time at elevated temperature to first rupture the biosolids cells and further to complete the deoxidation reactions to convert the cell constituents to char. While a continuous reaction is discussed here, the present invention also contemplates a batch or semi-batch reaction. As known to those of ordinary skill in the art, the methods for heating the batch reactors can be similar to those for a continuous reactor. For example, a batch reactor may be heated by direct steam injection, heating coils, or a combination thereof.
  • reactor-stripper tower One suitable alternative (not shown) for reactor 114 is a reactor-stripper tower.
  • a reactor-stripper tower has side-to-side baffles (or other vapor-liquid contacting media) arranged for downflow of partially heated slurry from the exchanger 112 contacting an upflow of steam and stripped carbon dioxide from a “reboiler” (the equivalent of exchanger 113 ), receiving char slurry from the base of the tower.
  • the tower preferably has a top-to-bottom temperature gradient from approximately the slurry outlet temperature of the exchanger 112 to a temperature somewhat lower than that leaving the illustrated simple reactor. In one embodiment, the temperature gradient ranges from about 200° C. to 260° C. (400° F. to 500° F.).
  • the temperature gradient is between about 150° C. to 315° C. (300° F. to 600° F.).
  • the carbon dioxide leaving the top of the reactor-stripper contains appreciable water vapor that needs to be condensed in a new condenser to distilled water and separated from carbon dioxide which leaves via a line 118 . While the let-down valve 116 and separator 117 are still required, little carbon dioxide remains to be separated in the separator.
  • char slurry The slurry leaving the reactor (or reactors), referred to as char slurry, consists of destroyed biosolids cells from which the bound water has been freed and which has also undergone fluid deoxidation, i.e. a molecular rearrangement characterized by splitting off carbon dioxide, resulting in a substantial increase in solids carbon content and a substantial decrease in solids oxygen content.
  • fluid deoxidation i.e. a molecular rearrangement characterized by splitting off carbon dioxide
  • char samples are comprised of about a 2% to 15% increase in solids carbon content, preferably with about a 4% to 12% increase.
  • the solids oxygen content decreases by about 35% to 50%.
  • the slurry undergoes a decrease in solids oxygen content of about 30% to 70%.
  • Char slurry flows from the reactor 114 to the heat exchanger 115 , where it is partially cooled by giving up heat to the liquid HTF which comes to it from the exchanger 112 via a line 142 .
  • the char slurry is cooled to a temperature ranging from about 150° C. to 200° C. (300° F. to 400° F.).
  • the temperature of the char slurry after leaving heat exchanger 115 is between about 100° C. to 260° C. (200° F. to 500° F.).
  • the liquid HTF circuit is completed by a liquid HTF receiver 139 , a liquid HTF pump 140 and connecting lines 141 , 142 and 143 .
  • the services of the heat exchangers 112 and 115 could be performed by a single exchanger 160 ( FIG. 1A ) having the cold feed slurry on one side and the hot char slurry on the other, which would require passing slurries through both the tube and the shell sides.
  • Any deposits on the tube side of the heat transfer service would be relatively easy to clean. Fouling on the shell side would be difficult to correct, however, and heat transfer coefficients are much lower with a product-to-product exchanger.
  • the present invention contemplates dividing the service into two exchangers, with clean HTF being a “go-between”, both hot and cold slurries then being on the tube sides, with only clean HTF on the shell sides.
  • the duties of the two exchangers are essentially the same (differing only by radiation loss), the temperature ranges of the circulating HTF seeking their own equilibrium.
  • reacted biosolids char leaving the reactor 114 while still under pressure, is recycled via recycle line 162 back to the pressurized biosolids slurry before it enters the reactor 114 , as shown in FIG. 1A , in order to facilitate heating and reduce the viscosity of the slurry prior to biosolids cell destruction and subsequent deoxidation.
  • Vaporized HTF flows from a receiver 144 , through a line 145 , to the hot side of the exchanger 113 , in which it is condensed by the transfer of heat to partially heat the biosolids slurry, and then flows by means of a line 146 back to the receiver 144 .
  • Liquid HTF flows from the receiver 144 by natural convection (or a furnace charge pump, not shown, if pressure drop requires this) through the coils of a fired heater 147 , where it is partially vaporized by heat supplied by a fuel source 148 and flows back to the receiver 144 .
  • the fuel source is natural gas, propane, fuel oil, char slurry, char, or any combination thereof.
  • a combustion device such as a fluid bed, is employed to use char, char slurry, or a combination of char and an outside fuel source or waste source.
  • a gasifier is employed to use char, char slurry, or a combination of char and an outside fuel source or waste source.
  • a boiler is used to generate steam for process heat. The boiler could use char, char slurry, or a combination of char and an outside fuel source or waste source.
  • An HTF pump 149 takes suction from the bottom of the receiver 144 and circulates liquid vaporizable HTF to a facility 135 as a source of heat for char drying. After serving this purpose, it is returned, via line 150 , to the receiver 144 .
  • the pump 149 may also serve other auxiliary heating services (not shown) such as to a jacket for the reactor 114 to prevent heat loss.
  • the now-fluid char slurry flows through a cooler 119 , in which its temperature is lowered to near ambient by exchange with plant cooling water from a line 120 .
  • the cooled char slurry flows from cooler 119 to an automatic pressure let-down valve 116 , which has been responsible for maintaining the aqueous slurries under sufficient pressure to avoid vaporization.
  • the pressure let-down valve 116 reduces the pressure of the char slurry to a nominal pressure above atmospheric. This is achieved by liberating gaseous and dissolved carbon dioxide, which is separated from the char slurry in a separator drum 117 . Evolved carbon dioxide exits the separator drum 117 via aline 118 .
  • the pressure let-down valve 116 is subjected to strenuous conditions and has a high potential for clogging. Certain steps can be performed, however, to minimize these difficult conditions. For example, as previously mentioned, grinding or screening can be performed anytime before the pressure let-down valve 116 . In addition, a step prior to the pressure let-down valve 116 of further cooling the reacted slurry after the heat exchanger 115 , as shown, will reduce the amount of evolved gas and reduce the acceleration of particles across the pressure let-down valve 116 . Those of ordinary skill in the art will appreciate that several cooling techniques are suitable for use with the present invention. Cooling techniques could include counter-current shell and tube or double-pipe exchanger cooled by plant cooling water.
  • foaming may occur in either the storage tank 121 or the drum 117 , it may be advantageous to control foaming by letting down pressure in two or more stages. In another embodiment, foaming may be controlled by using a spray nozzle from the lower part of the drum 117 to spray a side stream into the drum 117 .
  • Some dissolved carbon dioxide separates in the tank 121 and leaves via a line 137 . If there is a use or market for carbon dioxide, this gas, along with that evolved in the drum 117 , leaving via the line 118 , may be subjected to purification. Otherwise, it will be collected and discharged through the flame of a fired heater 147 to destroy traces of odor-causing gases and/or for energy recovery. Approximately 25 to 27 pounds of carbon dioxide are released per ton of wet biosolids processed. Any sulfur compounds in the carbon dioxide will be treated with the necessary pollution control devices. All vent gases are conducted to the fired heater 147 to destroy traces of odor-causing gases.
  • Liquid char slurry flows from the bottom of the tank 121 to a dewatering facility 122 , where one or more commercially-available devices for the mechanical separation of liquids and solids is employed to separate the freed water from the char solids.
  • Suitable separation devices may include, but are not limited to, thickeners, hydroclones, centrifuges, pressure and vacuum rotary filters, horizontal filters, belt and rotary presses, and the like.
  • Liquid char slurry in the tank 121 will contain some heat and may be ideal for a further step of adding a chelating agent or other chemicals to remove phosphorus or other elements found in the original biosolids.
  • the chelating agents discussed above are also suitable for use at this stage in the process.
  • Char solids leave the dewatering facility 122 via a conveyance means 123 . Some or all of them may be directed to an eductor 124 in which they are mixed with sufficient water from a line 125 to form a pumpable, high energy density fuel slurry.
  • the fuel slurry is accumulated in a tank 126 for off-loading to a pipeline or tank truck, as required, by means of a fuel slurry pump 151 and a line 152 .
  • the damp char may be conveyed by conveyance means 127 and 128 to a damp char hopper 136 to be off-loaded, as required, into hopper-bottom trucks 156 .
  • part or all of the char leaving the dewatering facility 122 can be directed to a drying and/or pelletizing facility 135 via conveyance means 127 , which, utilizing commercially-available equipment, dries and compacts or pelletizes the solids.
  • Heat required for the drying is supplied by a stream of hot liquid HTF from a vaporizable HTF receiver 144 by a HTF pump 149 which, after providing the necessary heat, is returned, via line 150 , to the receiver.
  • Dried char fuel is accumulated in a dried char silo 153 , to be off-loaded to hopper-bottom trucks 155 and transported to market. In one embodiment (not shown), dried char fuel is cooled prior to being accumulated in the dried char silo 153 .
  • the dried product is stored under nitrogen blanket to prevent dust explosions and fire in the event that the product is not transported directly from the facility.
  • Evaporated water from the dryer 135 flows through a condenser 138 , and the condensate is transported via a line to the freed water tank.
  • the heat required for the drying facility 135 can be produced by at least one of the methods of a fluid bed, boiler, or combusting gas from a gasifier.
  • the fuel source for the heat required for the drying could be at least one of char, char slurry, or a combination of char and an outside fuel source or waste source.
  • the gas from a digester at an adjacent wastewater treatment plant is utilized as fuel for at least one of the process heater and the dryer.
  • char dried in the drying facility 135 may be diverted to a mixing device with which it is incorporated into a fuel oil.
  • the technology resembles that of the coal-oil mixture (COM) programs developed and tested in the 1980s. While not conforming to existing fuel oil specifications, such an addition would add heating value and, in some cases, reduce the sulfur content at low cost.
  • This new fuel is of interest for users where ash is not a problem, such as in cement kilns and blast furnaces.
  • any grade of distillate or residual fuel oil can be used, most likely candidates are off-spec slop oils, refinery fuel, used lube oil, and the like.
  • the oil-char slurry is also attractive for in-plant fuel uses.
  • Freed water separated from damp char in the facility 122 flows through a line 129 to a freed water tank 130 , from which it is pumped by a freed water pump 131 , either via a line 132 to a comminuting and slurrying facility 104 and/or tank 106 , and/or it is returned to the wastewater treatment plant (WWTP) via line a 134 .
  • WWTP wastewater treatment plant
  • Solid biomass wastes as from agriculture and forestry, may be charged via a conveyor 101 to the comminuting and slurrying facility 104 , employing known technology described, for example, in U.S. Pat. No. 5,685,153, the entire disclosure of which is incorporated by reference herein.
  • Low-grade carbonaceous fuels such as Powder River Basin sub-bituminous coal
  • a conveyance means 102 may alternatively or additionally be charged to the facility 104 via a conveyance means 102 .
  • Recycled water is added to the facility as required for specified slurry viscosity by means of the line 132 , and/or fresh water by means of the line 103 .
  • the slurried hydrophilic feedstock is transferred via a line 105 to the storage tank 106 .
  • FIG. 2 is a flow diagram of a combination of a wastewater treatment plant (WWTP) operating in accordance with the present invention and, adjacent thereto, an efficient biosolids processing facility operating in accordance with the present invention and employing fluid deoxidation to economically convert biosolids into a combustible material, resulting in the elimination of most of the water from WWTP biosolids, and particularly the water bound in the biosolids cells, that otherwise inflate the cost of transporting and/or evaporating the water from the biosolids and thereby make the use of biosolids unfeasible.
  • Combustible gas from the WWTP's anaerobic digestion may be used to provide heat needed for the deoxidation, thus saving the cost of purchased fuel.
  • treated water from the WWTP can be utilized for slurrying water for the fluid deoxidation unit.
  • the WWTP can also treat the effluent from the deoxidation unit.
  • WWTP 201 receives storm drainage via one or more conduits 203 and sewage via one or more conduits 204 .
  • a WWTP typically employs atmospheric air entering via a conduit 205 and various customary additives, such as flocculants and lime, via a transport system 206 .
  • This conventional treatment of sewage and wastewater results in the production of a digester gas, leaving the WWTP via a conduit 207 , which is utilized as a fuel source for the present invention.
  • the treatment produces a viscous sewage sludge, i.e. a sludge or slurry of biosolids leaving through a line 208 .
  • the concentration of solids will typically be in the range of between about 3% to 40% and averaging about 20%. Because biosolids contain about 80% bound water, they are expensive to haul to acceptable disposal sites, to combust with the water present, or to attempt to physically dewater them.
  • a deoxidation unit 202 employing the process of FIG. 1 , is installed as close as feasible to the source of the biosolids.
  • the slurry is readily mechanically dewatered to contain about 35% to 65% solids.
  • the now-separable (freed) water (about 90% of that in the raw biosolids) is recycled to the WWTP through a line 211 , where it may be pretreated with membranes, ammonia removal technologies, anaerobic digestion technologies, or reverse osmosis technologies.
  • the char remaining has only about 15% to 17% of the weight of the raw biosolids, resulting in large cost savings for transporting the char to a point of use or disposal.
  • Undried low-moisture char exiting via suitable means 210 , may be acceptable at a nearby landfill, to which it is transported by a suitable conveyor or carrier 212 . It may similarly be transported to a nearby incinerator, via a means 213 , where its incineration will require much less fuel than the corresponding raw biosolids would consume. In addition, either dried or undried char may be transported to a nearby cement kiln, via a means 214 , where it requires significantly less purchased fuel than would be needed for an equivalent amount of raw biosolids.
  • the char may also be transported, via a means 215 , to a chemical plant where (aided by high reactivity) it is readily converted to fuel or synthesized gas, to oxygenated compounds, to carbon fibers, to fertilizer production, and/or to landfill.
  • the low-moisture char may be transported, by a means 216 , either as a pumpable slurry or as dry pellets, to a thermal power station where its high reactivity permits efficient combustion with low excess air and high carbon burnout.
  • the tipping fee is the fee paid by the WWTP to the owner of the processing unit for managing its biosolids.
  • FIG. 3 is a flow diagram illustrating an efficient biosolids processing facility for converting biosolids into a combustible, preferably carbonized material that is combined with a cement kiln.
  • This aspect of the present invention highlights the drastic reduction of water that would otherwise accompany raw biosolids into the kiln, enabling a substantial increase in the amount of biosolids consumed, with a proportionate increase in tipping revenue received by the processor and Btus charged to the kiln.
  • a fluid deoxidation unit 301 employing the process described with respect to FIG. 1 , is installed as close as feasible to one or more WWTPs, the source of the biosolids, as indicated by a transport means 303 .
  • a transport means 303 By rupturing the biosolids cell walls and discharging carbon dioxide that may be formed at the same time (line 304 ), the resulting char can now be readily mechanically dewatered to comprise about 35% to 65% solids.
  • the now-separable water (about 90% of that in the raw biosolids) is recycled to the WWTP through a line 305 or is used as recycle water for process slurrying.
  • Char either as a concentrated slurry, a wet solid, or a dried solid, is transported to a cement kiln 302 via a transport means 306 .
  • the basic ingredients of Portland cement limestone, clay and shale
  • these ingredients are contacted counter-currently with hot flue gas, which raises the temperature to drive off water of crystallization and calcine the limestone.
  • waste combustibles such as used tires and broken asphalt, are charged through a conduit 311 .
  • fuel such as coal, oil or gas is fired, together with combustion air, into the lower part of the preheat section.
  • the preheated mix is then discharged into one end of a horizontal, rotating kiln.
  • preheated ingredients travel to the opposite end of the rotating kiln, they are further heated to the temperature necessary for them to react and form cement clinker by firing, at a discharge end, primary fuel delivered through a conduit 312 (which may include biosolids char), along with the corresponding combustion air supplied via a combustion air fan (not shown) and a conduit 313 .
  • a conduit 312 which may include biosolids char
  • Cement clinker exits the kiln via heat exchange with combustion air, through a conduit 315 .
  • the cooled clinker is ground and blended with gypsum to form Portland cement.
  • biosolids char Most of the ash constituents of biosolids char are tolerable in Portland cement, with the exception of soluble cations, such as sodium and potassium and the sulfates and chlorides, which go primarily to the effluent from the liquid deoxidation unit and are returned via a conduit 305 to the WWTP.
  • soluble cations such as sodium and potassium and the sulfates and chlorides
  • the exception is phosphorus, which often is bound in insoluble form by iron. It is possible that the phosphorus content could limit the amount of biosolids char a given cement kiln can accept.
  • a chelate solution (or other solubilizing agent) may be employed via a line 316 to extract some of this element.
  • the phosphorus-containing extract is then discharged through a line 317 and must be disposed of in a manner that avoids returning it to the WWTP.
  • the inorganic fraction of biosolids can be as high as about 50% on a dry basis. This inherent ash found in biosolids can reduce the quantities of limestone, clay and shale input in lines 307 , 308 and 309 , respectively.
  • unit 301 is located near the cement kiln 302 , a portion of a wastewater stream 305 can be utilized in the cement kiln 302 for cooling or other purposes, or in NOx reduction.
  • Waste heat from the stream 314 , or other waste heat streams, including radiation heat can be utilized by unit 301 as process heat for the system including heating the feed material, process heat, or drying the reacted product.
  • Evolved carbon dioxide from the stream 302 can be conducted to the cement kiln 302 for heat recovery or odor reduction.
  • a portion of the fee goes to the owner of the unit 301 , as indicated by a dashed line 319 , and the remainder goes to the owner of the cement kiln 302 as indicated by a dashed line 320 .
  • FIG. 4 is a simplified flow diagram of an efficient biosolids processing facility 401 employing deoxidation to convert biosolids into a combustible material in close proximity to and combined with a thermal power station 402 .
  • the unit 401 is typified by FIG. 1 , charging biosolids from a WWTP.
  • FIG. 1 since the supply of biosolids available to a station of economic size is unlikely to be sufficient for its fuel needs, it also represents a family of liquid deoxidation processes charging a spectrum of renewable biomass and/or hydrophilic low-rank fossil fuel. With any or all of these potential fuels, liquid deoxidation makes them less hydrophilic and more uniform and thermally efficient for combustion in the power station 402 .
  • the station 402 represents a spectrum of conventional and unconventional combustion systems culminating, via steam turbine or gas turbine combined cycles, in the production of electricity for the local market and/or the national grid.
  • Biosolids are charged to the unit 401 via a line 403 .
  • biomass waste as paper mill sludge or from agriculture or forestry, is delivered by a transport means 404
  • hydrophilic low-rank fossil fuel is delivered through a transport means 405 .
  • Water as required to form a pumpable charge slurry is added through a line 406 .
  • the now excess water is returned to a WWTP, or treated for discharge by known means, via a line 407 .
  • Uniform (dewatered) high energy density char slurry, or dried and pelletized char is delivered through a transport means 408 to the station 402 .
  • the char or char slurry transported by the transport means 408 is combusted by one of the known methods to yield thermal energy for the generation of steam, which is expanded through conventional steam turbines driving electric generators, or it may be partially oxidized (with either air or commercial oxygen) to yield a fuel gas subsequently burned in a gas turbine combustor driving an electricity generator, the hot exhaust gas from which generates steam for an integrated steam turbine-driven generator.
  • the partial combustion of char may be accomplished according to known processes separating the ash as a fluid slag, or in accordance with U.S. Pat. No. 5,485,728, the entire disclosure of which is incorporated by reference herein, which teaches separation of the ash particles in an aqueous slurry.
  • supplemental fossil fuel can be supplied via a transport means 410 .
  • Air for the combustion or partial combustion of the biomass and/or fossil fuel char is supplied through a line 411 .
  • flue gas (or gases) from the combustion at the station 402 is (are) discharged through a stack 412 .
  • Treated boiler feed water makeup is supplied through a line 413 , and blowdown required to maintain boiler water within specifications is discharged via a line 414 to the unit 401 , where it may comprise some of the water needed to form a sufficiently fluid feed slurry to the deoxidation operation.
  • One of the known methods of controlling the emission of nitrogen oxides from atmospheric pressure boilers is overfiring with a reactive fuel above the main flame zone. Because of its volatiles content and high reactivity, biosolids char is a suitable fuel for this purpose, and a portion of that from the conveying means 408 can be diverted by way of a transport means 416 for nitrogen oxide reduction.
  • the product of the combination, electricity, is delivered from the site via electric cables 417 .
  • the biosolids treatment unit 401 is shown as though it had the capacity and raw material supply to furnish the power station 402 with sufficient char fuel.
  • a treatment unit 401 may be located adjacent to the power station 402 , and one or more such units 401 may be installed at other location(s) close to the raw material sources. This gives the operator the flexibility to employ tailored deoxidation temperatures, optimized for the particular feedstock.
  • dry char can then be shipped to the power station 402 by road or rail or, if economics dictate, it can be supplied as an aqueous slurry via a pipeline.
  • the flow of money, in the form of a tipping fee, from the WWTP to the deoxidation unit, is indicated by a dashed line 418
  • FIG. 5 is a simplified flow diagram of a combination comprising a thermal dryer unit 501 and a cement kiln 502 .
  • the thermal dryer unit 501 is installed as close as feasible to one or more cement kilns 502 , employing principally the same configuration as shown in and described in conjunction with FIG. 3 , but without deoxidizing the biosolids.
  • Biosolids are supplied via a transport means 503 .
  • a line 505 for scrubbing and condensing or, alternatively, is conducted via a line 517 back to the kiln to be utilized in the kiln as make-up water or for NO x reduction.
  • the resulting dried biosolids are conducted to the kiln via a line 506 where the Btu value as well as the value of the ash are utilized.
  • the primary ingredients such as are shown in FIG. 3 , are added to the kiln at the lines 507 , 508 , 509 through a conduit 510 .
  • waste combustibles are added, such as used tires and broken asphalt charged through a conduit 511 .
  • combustion air and primary fuel arrive via conduits 513 and 512 , respectively.
  • Cement klinker exits the kiln via a conduit 515 .
  • thermal drying has an inherent energy penalty from the latent heat in the evaporation of water, this penalty can be entirely or partially overcome by integrating with the cement kiln and utilizing heat from the kiln via a conduit 518 . More specifically, flue gas, normally traveling via a conduit 514 to an appropriate discharge, can be directed via a conduit 516 to the thermal dryer, thereby reducing the need for primary fuels at thermal dryer 501 for evaporating the water liberated from the biosolids.
  • biosolids char As discussed briefly above, because the potential supply of biosolids char is smaller, by orders of magnitude, than the general fuels market, other substances, for example biomass, can be co-processed in a liquid deoxidation unit, or processed in parallel equipment, and the resulting chars blended before being used as a fuel, for example in accordance with the teachings of U.S. Pat. No. 5,485,728.
  • Several locations, such as Hawaii (biosolids, pineapple and sugar cane wastes) and Sacramento, Calif. (biosolids and rice hulls and stalks) offer sites for slurry co- or parallel deoxidation. Paper mill and paper recycling sludges, although they may require alkali addition to neutralize chlorine, are other promising sources of supplemental hydrophilic biomass. These methods afford a means of consolidating diverse sources into a uniform liquid or solid char slurry fuel.
  • a cement kiln in the southeastern U.S. has a production capacity of 3,200 tons/day. To reach temperatures required to form cement “clinker”, it fires low-grade coal, supplemented to some extent by charging scrap rubber tires. Sensible heat in the flue gas, after preheating mineral charge and combustion air, may be taken advantage of to dry and incinerate 20 tons/day (dry basis) of biosolids from area wastewater treatment plants. Although every ton of dry biosolids constituents is accompanied by about four tons of water (giving the biosolids a negative heating value), revenue from the tipping fee offsets the cost of extra coal that must be fired. However, the amount is limited by the thermal capacity to evaporate the water and by the increased volume of flue gas, increasing pressure drop and fan horsepower.
  • the kiln may use biosolids dewatered and deoxidized in accordance with the present invention at one or more of the nearby WWTPs. As such, about 80% to 94% of the water formerly charged with the raw biosolids bypasses the kiln, permitting it to charge seven times as much deoxidized material without exceeding thermal capacity and fan horsepower limits.
  • the biosolids disposed of by the kiln can be increased by a factor of about 700%, with a corresponding increase in tipping fees.

Abstract

In the processes for treating municipal sewage and storm water containing biosolids to discharge standards, biosolids, even after dewatering, contain typically about 80% water bound in the dead cells of the biosolids, which gives biosolids a negative heating value. It can be incinerated only at the expense of purchased fuel. Biosolids are heated to a temperature at which their cell structure is destroyed and, preferably, at which carbon dioxide is split off to lower the oxygen content of the biosolids. The resulting char is not hydrophilic, and it can be efficiently dewatered and/or dried and is a viable renewable fuel. This renewable fuel can be supplemented by also charging conventional biomass (yard and crop waste, etc.) in the same or in parallel facilities. Similarly, non-renewable hydrophilic fuels can be so processed in conjunction with the processing of biosolids to further augment the energy supply.

Description

CROSS REFERENCE TO RELATED APPLICATION
This application is a continuation of U.S. patent application Ser. No. 11/269,499, now U.S. Pat. No. 7,909,895, filed Nov. 7, 2005, the disclosure of which is hereby expressly incorporated by reference herein in its entirety.
FIELD OF THE INVENTION
Sludge from sewage and wastewater treatment plants, and the biosolids it contains, represents a serious disposal problem. The Water Environment Federation (WEF) formally recognized the term “biosolids” in 1991, and it is now in common use throughout the world. The WEF defines “biosolids” as the soil-like residue of materials removed from sewage during the wastewater treatment process. During treatment, bacteria and other tiny organisms break sewage down into simpler and more stable forms of organic matter. The organic matter, combined with bacterial cell masses, settles out to form biosolids. According to USEPA, biosolids that meet treatment and pollutant content criteria “can be safely recycled and applied as fertilizer to sustainably improve and maintain productive soils and stimulate plant growth”.
The sludge is a mixture of biosolids (comprised primarily of dead organic cells which are a by-product of treating sewage and wastewater so that it can be released into open waters) and varying amounts of free water. Free water can be at least partially removed by mechanical dewatering methods. In addition to the free water, the biosolids contain cell-bound water, which can make up as much as 80% of the volume of biosolids and is impossible to remove by mechanical dewatering methods. The large amounts of water contained in such sludge give it a highly negative heat value which makes the cost of incinerating it prohibitive because large amounts of costly fuel would be required to drive off the cell-bound water. In view thereof, such sludge is presently used as landfill or as a fertilizer that can be spread over land, because sewage sludge frequently contains nitrogen and phosphor, for example. However, the sludge also contains harmful substances, generates undesirable odors, and can lead to serious contamination of the soil or the landfill from, amongst others, heavy metals.
In the processes for treating municipal sewage and storm water to discharge standards, solid constituents are concentrated into a by-product, often referred to as sewage sludge. Sewage sludge is a mass or agglomeration of dead organic cells and other solids, called biosolids, which are mixed with varying amounts of water of correspondingly varying viscosity. Irrespective of the degree to which the mass of biosolids is mechanically dewatered, the remaining mass of biosolids typically contains about 80% water, because much of the water is bound inside the dead cells, giving the biosolids mass a negative heating value, thereby making biosolids effectively useless for purposes of extracting heat value from them. Thus, biosolids still are disposed of in landfills or by spreading them on agricultural land as a fertilizer that supplies nitrogen and phosphorus. However, biosolids also may contain live viruses and pathogens and toxic heavy metals, inspiring heated opposition from environmental interests, while their high water content drastically increases the cost of transporting them to a point of use.
According to the present invention, the raw biosolids are heated following their discharge from the sewage treatment plant to rupture the cells, thereby releasing the large quantities of cell-bound water. The temperature is sufficiently high so that the cell structure is destroyed and carbon dioxide is split off to lower the oxygen content of the biosolids. This results in the formation of char that is not hydrophilic and can be efficiently dewatered and/or dried. This char is a viable renewable fuel.
In a further development of the present invention, it is possible to increase the availability of renewable fuels by converting biomass (such as untreated yard and crop waste, etc.) in the same or parallel facilities. Similarly, non-renewable hydrophilic fuels can be so processed to further augment the energy that can be extracted from biosolids in accordance with the invention.
BACKGROUND OF THE INVENTION
There is a growing wave of public support for renewable energy popularly called “Green Power”. Several well-known companies, according to Power magazine for May 2003, including General Motors, IBM, Dow Chemical and Johnson & Johnson, have announced plans to purchase a portion of their power requirement from “green” sources. Some companies have even announced intentions to replace all of the electricity used in their manufacturing with “green power”. Pillars of fossil energy supply, such as Chevron, British Petroleum (BP) and Shell Oil, have announced their intentions to support environmental causes. In fact, BP is an important supplier of solar energy panels. There is a “Green Power Market Development Group” of the World Resources Institute (WRI), aiming to develop 1,000 Megawatts (MW) of new, cost-competitive “green power” by 2010.
In addition, more than a dozen state legislatures require power marketers to phase in specific and increasing percentages of power from renewable sources. New York has mandated that state agencies must buy 25% of their power from renewable sources by 2013; currently 19.3% of the energy produced in New York is generated from renewable sources (New York Public Service Commission). California has passed legislation requiring that 20% of utilities' electricity in the state be produced from renewable sources by 2017. In fact, one California utility, Pacific Gas and Electricity (PG&E), advertises that more than 30% of its electricity now comes from renewable sources. At least 36 U.S. power retailers now offer a “green power” alternative. Europe also takes renewable energy seriously, targeting 20% of its generation from renewables by 2020.
Conventional renewable energy generally covers origination from solar, wind, hydro-electric, geothermal, biomass and landfill gas. There is some question as to how the demand for renewable energy will be met. Solar and wind are growing, but from a very small base. Hydro-electric and geothermal have limited new sites and face ecological opposition. Landfill gas is limited and also criticized for air pollution. There are currently no other renewable sources which might be tapped to fill the large gap between supply and demand.
Biomass has long been used as a renewable energy source. For example, wood and forestry, as well as agricultural, by-products have been used as fuels for centuries by mechanically firing them in furnaces and boilers with high excess air and low efficiency. The National Renewable Energy Laboratory (NREL) defines biomass as: “organic matter available on a renewable basis. Biomass includes forest and mill residues, agricultural crops and wastes, wood and wood wastes, animal wastes, livestock operation residues, aquatic plants, fast growing trees and plants and municipal and industrial wastes.” According to The Sandia National Laboratory's Combustion Research Facility (CRF), combustion is involved in 85% of the world's energy use. If biomass is to make a meaningful contribution to renewable energy, it will be, directly or indirectly, as a fuel.
Sewage sludge, and the large amounts of biosolids it contains, with their cell-bound water, has not previously been considered an energy source. Due to their large bound water content, biosolids have a negative fuel value and cannot be incinerated unless heated with expensive fuel that must be purchased. Such an incineration of biosolids may be desirable to avoid having to spread them on land, thereby eliminating or at least reducing possible environmental contamination, but at a very substantial cost, namely the additional heat that must come from the fuels to incinerate them.
The production of biosolids in the U.S. is estimated to be between 7.1 and 7.6 million (short) dry tons per year. Ocean dumping has been prohibited since the 1980s. The predominant disposition is spreading the biosolids on agricultural land as a fertilizer. Other dispositions are dumping in landfills and incineration.
In 1998, the production of biosolids in Europe was reported to be 7.2 million dry metric tons, and 25% was disposed to landfills. Production is expected to increase to at least 9.4 million metric tons in 2005, land application accounting for 54%, landfilling decreasing to 19%, and incineration growing to 24%—although incineration is estimated to cost five times as much as landfilling.
In 2001, biosolids production in Japan was reported to be 1.7 million dry metric tons. 40% was composted and the remainder was incinerated or used to produce cement.
After strenuous mechanical dewatering and digestion in sewage treatment plants, the solids concentration in biosolids still only ranges from about 14-30%, and is typically no more than about 20%, which means that every ton of biosolids, treated and dewatered in accordance with the prior art, is accompanied by about four tons of water, the bulk of which is bound in the dead cells. The cost of shipping the inert water limits the distance it can be moved from its source, usually a wastewater treatment plant (WWTP). These factors give biosolids a negative value. As a result, the WWTP must pay to have someone dispose of the biosolids. Such a payment is often called a “tipping fee”.
As the options for biosolids disposal become more challenging and the disposal options are moved farther from the source, disposal costs and transportation costs have become increasingly significant economic burdens. To reduce this burden, industry has focused on volume and weight reduction. The wastewater industry has made extensive efforts to remove the water from the biosolids generated at treatment plants. A typical WWTP may employ centrifuges, belt presses, rotary presses or other processes to physically force the water from the biosolids. A polymer and other chemicals may be added to assist in dewatering. Nevertheless, such mechanical dewatering methods used by WWTPs are inefficient and costly and incapable of appreciably reducing the amount of water bound in the cells of the biosolids.
The U.S. Environmental Protection Agency (EPA) grades biosolids according to regulation “40 CFR Part 503” as Class A and Class B. This regulation concerns primarily the application of biosolids to agricultural land, to which there is vocal and growing environmental opposition. For example, environmentalists condemn the use of biosolids as a fertilizer because of their content of living disease-causing organisms (pathogens and viruses) and heavy metals (such as lead, mercury, cadmium, zinc and nickel), as well as their damage to groundwater quality. In addition, environmentalists raise concerns about “quality of life” issues, such as insects and odors, associated with biosolids. As such, land application of Class B biosolids is banned in a number of counties, and more counties and states are expected to follow. In one case, where 70% of the biosolids were Class B, the banning of land application in adjacent counties nearly doubled the tipping fee from about $125 per dry ton to about $210-$235.
Furthermore, the high cell-bound water content of biosolids makes their incineration difficult for many industries. For example, the cement industry is reputed to be the world's third largest energy user. It requires the equivalent of about 470 pounds of coal to make each ton of cement. To conserve fossil fuel, 15 cement plants in the U.S. burn fuel-quality hazardous waste, and about 35 other plants use scrap tires to supplement fossil fuel. A growing method of disposing of biosolids is to incinerate them in cement kilns. Since their net fuel value is negative, this practice is only viable because of the revenue received by the kiln operator, for example, from the tipping fee, since additional fuel, such as coal, must be fired to eliminate the water bound in biosolids. In addition, in the manufacture of cement, certain elements contained in biosolids, such as chlorine, phosphorus, sodium and potassium, are not desired because they adversely affect the quality of the cement.
In the past, the requirement to dispose of biomass in general was coupled with attempts to extract heat energy from it in order to reduce disposal costs and the environmental burden of landfills. Attempts to extract energy from such materials were limited to combusting low-grade fuels and solid waste. For example, previous processes for deriving fuel from municipal solid waste (MSW) generally focus on adding alkali to assist in the removal of the majority of contained chlorine in the form of PVC found in MSW. In addition, various methods for processing relatively low-grade carbonaceous fuel, such as sub-bituminous and lignite coals, are known to those of ordinary skill in the art. In both scenarios, however, low-grade fuels are used as raw materials.
A number of schemes for the pyrolysis of biosolids have been advanced. However, they all have been forced to contend with the fact that biosolids contain about four times as much water as solid material, even after conventional dewatering at the treatment plant, for example. It is impossible to reach pyrolysis temperatures until all of the water has been vaporized, which requires at least 4000 Btu per pound of solids, which, at best, might be equal to its fuel value, before allowing for capital and operating costs.
As the foregoing demonstrates, the disposal of biosolids has become increasingly expensive and controversial. A need exists in the art for a method to cleanly and economically dispose of biosolids. The current invention provides a method to dispose of biosolids while concurrently producing an economically more viable renewable fuel.
To the extent that biosolids alone cannot meet the growing demand for renewable energy, the biosolids conversion to a useable fuel in according with the present invention can be combined with extracting energy from other sources such as biomass. Thus, the present invention provides a method and system to convert biosolids, alone or with biomass, into a viable renewable fuel in an environmentally benign manner.
SUMMARY OF THE INVENTION
As understood by applicants, biosolids are composed primarily of dead cells which have cell-bound water. When subjected to sufficient pressure to keep the water liquid, a heating of a slurry or sludge containing biosolids to a first, relatively lower, temperature causes the biosolids cells to rupture, which liberates the water bound inside the cells and thereby converts the biosolids from a substance which cannot practically be dewatered to a new fuel from which the water can be readily removed mechanically. The further heating of the biosolids additionally splits off carbon dioxide, thereby lowering the oxygen content of the biosolids and converting the biosolids into char. Once dewatered, the char has a positive heating value and can be used directly as a fuel, thereby releasing the heat energy that was previously inaccessibly bound in the biosolids.
For example, in combination with a wastewater treatment plant (WWTP), the present invention provides a method to produce a viable, renewable fuel from biosolids by converting the biosolids into a relatively dry, combustible material. In many cases, the process can be integrated with the existing infrastructure of the WWTP. Since the treated biosolids have substantially no bound water, freed water from the cells can be returned to the WWTP. The remaining cell materials become much less hydrophilic, which gives them a positive heating value and allows them to be shipped to the desired destination at a much reduced cost. If the WWTP is equipped with an anaerobic digestion stage, the gas produced can support the fluid deoxidation with fuel used in its operation. Pathogens are destroyed, and when the dewatered biosolids are heated sufficiently to carbonize them, the resulting char product contains reduced levels of most water-soluble impurities, including sodium, potassium, sulfur, nitrogen, chlorine and organic compounds, which are separated with the excess water. Biosolids char is a new player on the energy scene and is a low-cost, renewable fuel for many energy-consuming industries.
Although acceptable to incinerators and landfills, biosolids char is most productively used where its energy content is utilized. For example, in one embodiment, the method and system of the present invention is used in conjunction with a cement kiln to increase the thermal efficiency of the cement kiln and cement manufacture, while disposing of biosolids that would otherwise constitute undesirable waste. In addition, the inert material found in the biosolids can become a part of the product. Therefore, not only is the heating value in biosolids utilized, but the inerts leave no negative by-products from this configuration.
Since biosolids are produced as a viscous slurry, little preparation is required, except blending for uniformity. Following heating of the biosolids slurry under pressure to a temperature at which the cell walls rupture, the further heating of the biosolids results in a significant molecular rearrangement of the cells, splitting off of a substantial proportion of its oxygen as carbon dioxide, which carbonizes organic substances and yields so-called char that is readily incinerated. The temperature necessary for this molecular rearrangement varies but is typically between 177° C. and 315° C. (350° F. and 600° F.). The aggressively hydrolyzing conditions free anions to dissolve in the aqueous phase. Previously bound cations, such as sodium and potassium, are likewise made accessible to aqueous dissolution and subsequent removal and/or disposal.
Compared to the incineration of (raw) biosolids, in cement kilns or dedicated incinerators, the positive energy content of biosolids char substantially decreases the amount of supplemental fuel which must be purchased. Moreover, soluble cations, sources of low temperature slag in boilers and undesirable in cement, have been largely removed with the freed water.
Cement kiln and incinerator facilities may prefer for the char to be dewatered to a maximum extent, resulting in the delivery and charging of a wet solid “char” containing only about 40% to 50% water, which is about one-fifteenth of that found in the raw biosolids. Alternatively, transport and handling considerations may cause such facilities to prefer char which has been dried and compacted or pelletized. The present invention has the capability to deliver char in either form.
In addition, the biosolids char produced with this invention, with or without char from other substances such as biomass, for example, provides a fuel that is useful to a variety of other fuel-consuming industries, including blast furnaces, foundries, utility boilers, the power industry, the paper industry, and other fossil fuel-utilizing industries. For example, the present invention contemplates a green power station where biosolids char is charged to a pulverized fuel or fluidized bed combustor to generate steam, or to a gasifier feeding clean fuel gas to an integrated gas-fired gas turbine combined cycle.
Furthermore, the char produced by the present invention can be the raw material for hydrogen fuel cells through partial oxidation to a fuel gas (largely carbon monoxide and hydrogen), followed by the water gas shift and the separation of carbon dioxide, as practiced in synthetic ammonia technology. It can be “refined” into liquid fuels by adaptations of “catalytic cracking”, “delayed coking” and “hydrocracking”, patterned after the established processes well known to the petroleum refining industry.
While the present invention is directed to the economic and ecologically sound disposition of biosolids, it can be combined with appropriately treated other substances, primarily biomass that requires disposal, including, but not limited to, paper mill sludge, food waste, agricultural wastes, hog manure, chicken litter, cow manure, rice hulls, bagasse, green waste, municipal solid waste, medical waste, paper waste, wood and wood waste, palm oil residue, refuse derived fuels, Kraft Mill black liquor, and short rotation energy crops, as well as hydrophilic non-renewable fuels such as low-rank coals.
In particular, the present invention relates to a process of converting biosolids into an economically viable fuel by applying sufficient pressure to the biosolids to maintain liquidity, heating the pressurized biosolids to a sufficient temperature to rupture cells and then to evolve carbon dioxide, depressurizing the resulting char slurry, separating the carbon dioxide from the char slurry, and removing at least a portion of the aqueous phase from the char slurry to provide an at least partially dewatered char product for further use. Additionally, the invention relates to reacting the dewatered char product with a gas comprising oxygen to thereby convert its fuel value into thermal energy and using the thermal energy or incinerating the fuel.
In sum, the present invention provides an environmentally acceptable disposition of biosolids, as well as energy for various energy consumers, such as cement kilns and electric power plants. In addition, the present invention provides: (a) a method to increase the availability and environmental acceptability of renewable fuels; (b) a method to minimize the quantity of wastes to be landfilled; (c) a process to reduce the moisture (water) content of waste going to landfill; (d) a process to raise the softening point of renewable fuel ash to reduce fouling and slagging; (e) a method of converting a non-uniform solid fuel, such as agricultural and forestry waste and/or paper mill sludge, into a uniform fuel; (f) a method to convert a bulky fuel into a fuel that is compact and easy to store and transport; (g) a process to convert a perishable fuel into a sterile fuel that is storable without deterioration; (h) a method to provide an economical means of cofiring an otherwise non-compliant fuel; (i) a method to provide a thermally efficient combination of liquid deoxidation and at least one of a wastewater treatment plant, a cement kiln, and a thermal power station; (j) a method to dry biosolids prior to introduction to a cement kiln or other similar facility; (k) a method to reduce the amount of water introduced to a cement kiln and other combustors; (l) a process to co-process multiple feedstocks utilizing fluid deoxidation; (m) a method to utilize the ash in biosolids and other biomass; (n) a method to remove (and recover) elements found in biosolids or other biomass such as phosphorus, chlorine or CO2; and (o) a process to remove the water from biosolids and biomass in order to further refine these materials or to reduce disposal costs or to utilize for fertilizer.
Thus, the present invention provides a method for the disposal of sludge generated at sewage and wastewater treatment plants in an economical and environmentally benign manner. The method is economically benign because the end product is ash that is free of odors, as well as harmful substances such as viruses or pathogens, and the ash has a small volume and is readily disposed of. The method is further economically viable because at the front end it benefits from the willingness of treatment plant operators to pay a tipping fee in order to dispose of the difficult-to-handle sewage sludge, and further because, at the other end of the cycle, the sludge will have been converted into a fuel with a positive heating value that can be used to generate further revenue or other items of value in the form of payments for the generated heat energy or, for example, trading the extracted heat for credits, desired products and the like.
Additional embodiments of the present invention will be apparent from the description and the drawings of this application.
BRIEF DESCRIPTION OF THE DRAWINGS
Further features and advantages of the invention can be ascertained from the following detailed description that is provided in connection with the drawing(s) described below:
FIG. 1 is a schematic flow diagram illustrating the process of the present invention for converting biosolids into a high energy density slurry or dry solid fuel as a renewable energy source;
FIG. 1A is a schematic flow diagram similar to FIG. 1 illustrating another process of the present invention for converting biosolids into a high energy density slurry or dry solid fuel as a renewable energy source;
FIG. 2 is a flow diagram in which the process of the present invention is used in a wastewater treatment plant;
FIG. 3 is a flow diagram in which the process of the present invention is used in the operation of a cement kiln;
FIG. 4 is a flow diagram in which the process of the present invention is employed in the operation of a thermal power station using additional fuels, such as low-rank coals; and
FIG. 5 is a flow diagram in which the process of the present invention is combined with a thermal dryer and used in a cement kiln.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 illustrates the conversion of biosolids to a viable renewable fuel. Biosolids may be delivered as sludge via a pipeline 107 from an adjacent wastewater or sewage treatment plant (WWTP) to a raw feed tank 106. Alternatively, biosolids may be delivered by a truck 108 and pumped by a sludge pump 109 via a line 110 to the tank 106.
Alternatively, the raw feed tank 106 can receive biosolids from multiple sources and be utilized as a mixing vessel whereby more dilute biosolids are mixed with thicker, more viscous biosolids to render a more pumpable feed. A commingling and slurrying facility 104 can also be utilized for this purpose.
In addition, the raw feed tank 106 or comminuting commingling and slurrying facility 104 can be the points whereby polymer is added to reduce the water content of the biosolids slurry or, alternatively, where water is added if the viscosity of the slurry is an issue.
Heat may be added to the tank 106 to enhance the viscosity of the biosolids. In addition, a shearing or grinding step may be added, for instance between the raw feed tank 106 and a pumping device 111. This shearing or grinding will lower viscosity as well as achieve the particle size uniformity necessary for optimal operation of a pressure let-down valve 116. Addition of heat, shearing and grinding will also enhance the performance of the pumping device 111 and allow a higher solids content material into the system.
In one embodiment, a screening device is added to remove large particle-size items to enhance the performance of any grinding, the pumping device 111 and/or the pressure let-down valve 116. For example, the screening device may be placed between the raw feed tank 106 and the pumping device 111. In another embodiment, the raw feed tank 106 or a similar device can be used to add a chelating agent or other suitable chemical to remove phosphorus or other elements found in the biosolids.
From the raw feed tank 106, the biosolids slurry is pumped to a pressure that will keep the water in the slurry in liquid phase during subsequent heating operations. For example, in one embodiment, the slurry is at a pressure ranging from about 400 to 1200 psi. In another embodiment, the pressure of the slurry is between about 250 to 1600 psi. Care must be exercised to provide a pumping device 111 with an adequate net pump suction head (NPSH), either hydraulically or by mechanical assistance, as with a screw conveyor, considering that the slurry may be very viscous and may carry dissolved gases.
An alternative (not shown), for reducing the service of the pumping device 111, is the addition of booster pumps in the process anywhere between the pumping device 111 and the let-down valve 116. A further alternative (not shown) for reducing the service of the pumping device 111 is the addition of freed water or reacted slurry before the pumping device 111.
The biosolids slurry is pumped through heat exchangers 112 and 113 before passing to a reactor 114. While passing through the heat exchanger 112 the slurry is heated by exchange with hot liquid heat transfer fluid (HTF), such as Therminol 59. In another embodiment (not shown), the slurry may be heated via heat exchange with steam, either directly or indirectly. The outlet temperature of the slurry leaving heat exchanger 112 may range from about 150° C. to 315° C. (300° F. to 600° F.), and is preferably between about 200° C. to 260° C. (400° F. to 500° F.). While passing through the heat exchanger 113, the slurry is further heated to the desired temperature at which the biosolids cell walls will rupture and to liberate water bound in the cells. The temperature is further preferably set so that the other constituents of the biosolids cells are carbonized to convert these constituents to char by heat exchange with hot liquid HTF. In an alternate embodiment, the condensing vapor of a vaporizable HTF, such as Therminol VP-1, is used to heat the slurry to the desired temperature. In one embodiment, this temperature is between about 200° C. to 260° C. (400° F. to 500° F.). In another embodiment, the temperature is between about 150° C. to 260° C. (300° F. to 500° F.). In still another embodiment, the temperature is between about 260° C. to 350° C. (500° F. to 650° F.).
While the design of the heat exchangers for use with the present invention is not critical, each may comprise two or more shells. The shells may be in parallel or in series. In one embodiment, the heat exchangers 112 and 113 are arranged in a series such that the biosolids slurry passes through heat exchanger 112 prior to heat exchanger 113.
The reactor 114 (which may comprise one or more reactors in parallel or series) provides time at elevated temperature to first rupture the biosolids cells and further to complete the deoxidation reactions to convert the cell constituents to char. While a continuous reaction is discussed here, the present invention also contemplates a batch or semi-batch reaction. As known to those of ordinary skill in the art, the methods for heating the batch reactors can be similar to those for a continuous reactor. For example, a batch reactor may be heated by direct steam injection, heating coils, or a combination thereof.
One suitable alternative (not shown) for reactor 114 is a reactor-stripper tower. Such a tower has side-to-side baffles (or other vapor-liquid contacting media) arranged for downflow of partially heated slurry from the exchanger 112 contacting an upflow of steam and stripped carbon dioxide from a “reboiler” (the equivalent of exchanger 113), receiving char slurry from the base of the tower. The tower preferably has a top-to-bottom temperature gradient from approximately the slurry outlet temperature of the exchanger 112 to a temperature somewhat lower than that leaving the illustrated simple reactor. In one embodiment, the temperature gradient ranges from about 200° C. to 260° C. (400° F. to 500° F.). In another embodiment, the temperature gradient is between about 150° C. to 315° C. (300° F. to 600° F.). The carbon dioxide leaving the top of the reactor-stripper contains appreciable water vapor that needs to be condensed in a new condenser to distilled water and separated from carbon dioxide which leaves via a line 118. While the let-down valve 116 and separator 117 are still required, little carbon dioxide remains to be separated in the separator.
The slurry leaving the reactor (or reactors), referred to as char slurry, consists of destroyed biosolids cells from which the bound water has been freed and which has also undergone fluid deoxidation, i.e. a molecular rearrangement characterized by splitting off carbon dioxide, resulting in a substantial increase in solids carbon content and a substantial decrease in solids oxygen content. For example, char samples are comprised of about a 2% to 15% increase in solids carbon content, preferably with about a 4% to 12% increase. In one embodiment, the solids oxygen content decreases by about 35% to 50%. In another embodiment, the slurry undergoes a decrease in solids oxygen content of about 30% to 70%.
Char slurry flows from the reactor 114 to the heat exchanger 115, where it is partially cooled by giving up heat to the liquid HTF which comes to it from the exchanger 112 via a line 142. In one embodiment, the char slurry is cooled to a temperature ranging from about 150° C. to 200° C. (300° F. to 400° F.). In another embodiment, the temperature of the char slurry after leaving heat exchanger 115 is between about 100° C. to 260° C. (200° F. to 500° F.). The liquid HTF circuit is completed by a liquid HTF receiver 139, a liquid HTF pump 140 and connecting lines 141, 142 and 143.
The services of the heat exchangers 112 and 115 (FIG. 1) could be performed by a single exchanger 160 (FIG. 1A) having the cold feed slurry on one side and the hot char slurry on the other, which would require passing slurries through both the tube and the shell sides. Any deposits on the tube side of the heat transfer service would be relatively easy to clean. Fouling on the shell side would be difficult to correct, however, and heat transfer coefficients are much lower with a product-to-product exchanger. As such, the present invention contemplates dividing the service into two exchangers, with clean HTF being a “go-between”, both hot and cold slurries then being on the tube sides, with only clean HTF on the shell sides. The duties of the two exchangers are essentially the same (differing only by radiation loss), the temperature ranges of the circulating HTF seeking their own equilibrium.
In one embodiment, reacted biosolids char leaving the reactor 114, while still under pressure, is recycled via recycle line 162 back to the pressurized biosolids slurry before it enters the reactor 114, as shown in FIG. 1A, in order to facilitate heating and reduce the viscosity of the slurry prior to biosolids cell destruction and subsequent deoxidation.
Vaporized HTF flows from a receiver 144, through a line 145, to the hot side of the exchanger 113, in which it is condensed by the transfer of heat to partially heat the biosolids slurry, and then flows by means of a line 146 back to the receiver 144. Liquid HTF flows from the receiver 144 by natural convection (or a furnace charge pump, not shown, if pressure drop requires this) through the coils of a fired heater 147, where it is partially vaporized by heat supplied by a fuel source 148 and flows back to the receiver 144. In one embodiment, the fuel source is natural gas, propane, fuel oil, char slurry, char, or any combination thereof. In an alternate embodiment (not shown), a combustion device, such as a fluid bed, is employed to use char, char slurry, or a combination of char and an outside fuel source or waste source. In another embodiment (not shown), a gasifier is employed to use char, char slurry, or a combination of char and an outside fuel source or waste source. In yet another embodiment, a boiler is used to generate steam for process heat. The boiler could use char, char slurry, or a combination of char and an outside fuel source or waste source.
An HTF pump 149 takes suction from the bottom of the receiver 144 and circulates liquid vaporizable HTF to a facility 135 as a source of heat for char drying. After serving this purpose, it is returned, via line 150, to the receiver 144. The pump 149 may also serve other auxiliary heating services (not shown) such as to a jacket for the reactor 114 to prevent heat loss.
After being partially cooled in the heat exchanger 115, the now-fluid char slurry flows through a cooler 119, in which its temperature is lowered to near ambient by exchange with plant cooling water from a line 120. The cooled char slurry flows from cooler 119 to an automatic pressure let-down valve 116, which has been responsible for maintaining the aqueous slurries under sufficient pressure to avoid vaporization. The pressure let-down valve 116 reduces the pressure of the char slurry to a nominal pressure above atmospheric. This is achieved by liberating gaseous and dissolved carbon dioxide, which is separated from the char slurry in a separator drum 117. Evolved carbon dioxide exits the separator drum 117 via aline 118.
The pressure let-down valve 116 is subjected to strenuous conditions and has a high potential for clogging. Certain steps can be performed, however, to minimize these difficult conditions. For example, as previously mentioned, grinding or screening can be performed anytime before the pressure let-down valve 116. In addition, a step prior to the pressure let-down valve 116 of further cooling the reacted slurry after the heat exchanger 115, as shown, will reduce the amount of evolved gas and reduce the acceleration of particles across the pressure let-down valve 116. Those of ordinary skill in the art will appreciate that several cooling techniques are suitable for use with the present invention. Cooling techniques could include counter-current shell and tube or double-pipe exchanger cooled by plant cooling water.
Because foaming may occur in either the storage tank 121 or the drum 117, it may be advantageous to control foaming by letting down pressure in two or more stages. In another embodiment, foaming may be controlled by using a spray nozzle from the lower part of the drum 117 to spray a side stream into the drum 117.
Some dissolved carbon dioxide separates in the tank 121 and leaves via a line 137. If there is a use or market for carbon dioxide, this gas, along with that evolved in the drum 117, leaving via the line 118, may be subjected to purification. Otherwise, it will be collected and discharged through the flame of a fired heater 147 to destroy traces of odor-causing gases and/or for energy recovery. Approximately 25 to 27 pounds of carbon dioxide are released per ton of wet biosolids processed. Any sulfur compounds in the carbon dioxide will be treated with the necessary pollution control devices. All vent gases are conducted to the fired heater 147 to destroy traces of odor-causing gases.
Liquid char slurry flows from the bottom of the tank 121 to a dewatering facility 122, where one or more commercially-available devices for the mechanical separation of liquids and solids is employed to separate the freed water from the char solids. Suitable separation devices may include, but are not limited to, thickeners, hydroclones, centrifuges, pressure and vacuum rotary filters, horizontal filters, belt and rotary presses, and the like.
Liquid char slurry in the tank 121 will contain some heat and may be ideal for a further step of adding a chelating agent or other chemicals to remove phosphorus or other elements found in the original biosolids. The chelating agents discussed above are also suitable for use at this stage in the process.
Char solids leave the dewatering facility 122 via a conveyance means 123. Some or all of them may be directed to an eductor 124 in which they are mixed with sufficient water from a line 125 to form a pumpable, high energy density fuel slurry. The fuel slurry is accumulated in a tank 126 for off-loading to a pipeline or tank truck, as required, by means of a fuel slurry pump 151 and a line 152. Alternatively, the damp char may be conveyed by conveyance means 127 and 128 to a damp char hopper 136 to be off-loaded, as required, into hopper-bottom trucks 156.
Alternatively, part or all of the char leaving the dewatering facility 122 can be directed to a drying and/or pelletizing facility 135 via conveyance means 127, which, utilizing commercially-available equipment, dries and compacts or pelletizes the solids. Heat required for the drying is supplied by a stream of hot liquid HTF from a vaporizable HTF receiver 144 by a HTF pump 149 which, after providing the necessary heat, is returned, via line 150, to the receiver. Dried char fuel is accumulated in a dried char silo 153, to be off-loaded to hopper-bottom trucks 155 and transported to market. In one embodiment (not shown), dried char fuel is cooled prior to being accumulated in the dried char silo 153. In another embodiment, the dried product is stored under nitrogen blanket to prevent dust explosions and fire in the event that the product is not transported directly from the facility. Evaporated water from the dryer 135 flows through a condenser 138, and the condensate is transported via a line to the freed water tank.
In one embodiment (not shown), the heat required for the drying facility 135 can be produced by at least one of the methods of a fluid bed, boiler, or combusting gas from a gasifier. The fuel source for the heat required for the drying could be at least one of char, char slurry, or a combination of char and an outside fuel source or waste source. In one embodiment (not shown), the gas from a digester at an adjacent wastewater treatment plant is utilized as fuel for at least one of the process heater and the dryer.
Although not shown in FIG. 1, nor entirely renewable, char dried in the drying facility 135, but not pelletized, may be diverted to a mixing device with which it is incorporated into a fuel oil. The technology resembles that of the coal-oil mixture (COM) programs developed and tested in the 1980s. While not conforming to existing fuel oil specifications, such an addition would add heating value and, in some cases, reduce the sulfur content at low cost. This new fuel is of interest for users where ash is not a problem, such as in cement kilns and blast furnaces. Although any grade of distillate or residual fuel oil can be used, most likely candidates are off-spec slop oils, refinery fuel, used lube oil, and the like. The oil-char slurry is also attractive for in-plant fuel uses.
Freed water separated from damp char in the facility 122 flows through a line 129 to a freed water tank 130, from which it is pumped by a freed water pump 131, either via a line 132 to a comminuting and slurrying facility 104 and/or tank 106, and/or it is returned to the wastewater treatment plant (WWTP) via line a 134. Depending on the rate scale for treatment at the WWTP, it may be economical to employ some pretreatment, by known commercial means, in a pretreatment facility 133. Any sludge which is derived from the pretreatment facility can be conveyed to the drying facility 135. As discussed earlier, the dried product may be stored under nitrogen blanket or other method to prevent dust explosions.
While the process flow diagram of FIG. 1 has been described with respect to the treatment of large amounts of biosolids, as accumulate most frequently at municipal sewage and wastewater treatment plants, those of ordinary skill in the art will appreciate that other substances, such as biomass, can be dewatered with the general process of the invention in addition to the biosolids to enhance the amount of fuel being generated. For example, fluid biomass wastes, such as papermill and paper recycling sludges, may be charged via a tank truck 108 or a pipeline 107 or a pump 109 and line 110. If the waste contains appreciable amounts of chlorine compounds, alkali of at least the chemical equivalent of the chlorine is also added (not shown). Solid biomass wastes, as from agriculture and forestry, may be charged via a conveyor 101 to the comminuting and slurrying facility 104, employing known technology described, for example, in U.S. Pat. No. 5,685,153, the entire disclosure of which is incorporated by reference herein.
Low-grade carbonaceous fuels, such as Powder River Basin sub-bituminous coal, may alternatively or additionally be charged to the facility 104 via a conveyance means 102. Recycled water is added to the facility as required for specified slurry viscosity by means of the line 132, and/or fresh water by means of the line 103. As outlined above with respect to the biosolids, the slurried hydrophilic feedstock is transferred via a line 105 to the storage tank 106.
The high reactivity of the biosolids char, as produced by a unit exemplified by FIG. 1, has been noted. This property of its carbonaceous molecules will be useful to a gasification facility, or a chemical plant using it as raw material for oxygenated organic compounds, either low molecular weight (such as acetic acid, alcohols, aldehydes and ketones) or higher molecular weight detergents, surfactants, plasticizers, lubricating oil additives, and the like. Among the future possibilities for char gasification is the shifting of the CO content of the gas to carbon dioxide and hydrogen, with subsequent separation of the carbon dioxide to yield hydrogen for fuel cells. This separation may well be performed by the new metal-ceramic membranes being developed for the U.S. Department of Energy (DOE) FutureGen project, in collaboration with Oak Ridge National Laboratory and Eltron Research.
FIG. 2 is a flow diagram of a combination of a wastewater treatment plant (WWTP) operating in accordance with the present invention and, adjacent thereto, an efficient biosolids processing facility operating in accordance with the present invention and employing fluid deoxidation to economically convert biosolids into a combustible material, resulting in the elimination of most of the water from WWTP biosolids, and particularly the water bound in the biosolids cells, that otherwise inflate the cost of transporting and/or evaporating the water from the biosolids and thereby make the use of biosolids unfeasible. Combustible gas from the WWTP's anaerobic digestion may be used to provide heat needed for the deoxidation, thus saving the cost of purchased fuel. Furthermore, treated water from the WWTP can be utilized for slurrying water for the fluid deoxidation unit. Moreover, the WWTP can also treat the effluent from the deoxidation unit.
In particular, WWTP 201 receives storm drainage via one or more conduits 203 and sewage via one or more conduits 204. Using known technology, a WWTP typically employs atmospheric air entering via a conduit 205 and various customary additives, such as flocculants and lime, via a transport system 206. This conventional treatment of sewage and wastewater results in the production of a digester gas, leaving the WWTP via a conduit 207, which is utilized as a fuel source for the present invention. The treatment produces a viscous sewage sludge, i.e. a sludge or slurry of biosolids leaving through a line 208. The concentration of solids will typically be in the range of between about 3% to 40% and averaging about 20%. Because biosolids contain about 80% bound water, they are expensive to haul to acceptable disposal sites, to combust with the water present, or to attempt to physically dewater them.
A deoxidation unit 202, employing the process of FIG. 1, is installed as close as feasible to the source of the biosolids. By rupturing the cellular structure and splitting off carbon dioxide from the molecules making up the biosolids, the slurry is readily mechanically dewatered to contain about 35% to 65% solids. The now-separable (freed) water (about 90% of that in the raw biosolids) is recycled to the WWTP through a line 211, where it may be pretreated with membranes, ammonia removal technologies, anaerobic digestion technologies, or reverse osmosis technologies. Upon drying, the char remaining has only about 15% to 17% of the weight of the raw biosolids, resulting in large cost savings for transporting the char to a point of use or disposal.
Undried low-moisture char, exiting via suitable means 210, may be acceptable at a nearby landfill, to which it is transported by a suitable conveyor or carrier 212. It may similarly be transported to a nearby incinerator, via a means 213, where its incineration will require much less fuel than the corresponding raw biosolids would consume. In addition, either dried or undried char may be transported to a nearby cement kiln, via a means 214, where it requires significantly less purchased fuel than would be needed for an equivalent amount of raw biosolids. The char may also be transported, via a means 215, to a chemical plant where (aided by high reactivity) it is readily converted to fuel or synthesized gas, to oxygenated compounds, to carbon fibers, to fertilizer production, and/or to landfill. The low-moisture char may be transported, by a means 216, either as a pumpable slurry or as dry pellets, to a thermal power station where its high reactivity permits efficient combustion with low excess air and high carbon burnout.
Equally as significant as the flow of materials and energy is a flow of money, in the form of a tipping fee, from the WWTP to the biosolids processing unit, as indicated by a dashed line 217. The tipping fee is the fee paid by the WWTP to the owner of the processing unit for managing its biosolids.
Since the supply of the new fuel discussed above will initially be small, it is optimal for local use. As such, one of the first fuel users to accept it is likely to be cement kiln operators, since they can to a large extent tolerate its high ash content. Other suitable areas of use are blast furnaces and foundries, since they are accustomed to firing coal or coke and to disposing of ash with other impurities as slag. As the supply of biosolids char increases, it will become of interest to general coal users, including thermal power stations. Such applications are addressed in more detail in the remaining figures.
For example, FIG. 3 is a flow diagram illustrating an efficient biosolids processing facility for converting biosolids into a combustible, preferably carbonized material that is combined with a cement kiln. This aspect of the present invention highlights the drastic reduction of water that would otherwise accompany raw biosolids into the kiln, enabling a substantial increase in the amount of biosolids consumed, with a proportionate increase in tipping revenue received by the processor and Btus charged to the kiln.
In particular, a fluid deoxidation unit 301, employing the process described with respect to FIG. 1, is installed as close as feasible to one or more WWTPs, the source of the biosolids, as indicated by a transport means 303. By rupturing the biosolids cell walls and discharging carbon dioxide that may be formed at the same time (line 304), the resulting char can now be readily mechanically dewatered to comprise about 35% to 65% solids. The now-separable water (about 90% of that in the raw biosolids) is recycled to the WWTP through a line 305 or is used as recycle water for process slurrying.
Char, either as a concentrated slurry, a wet solid, or a dried solid, is transported to a cement kiln 302 via a transport means 306. The basic ingredients of Portland cement (limestone, clay and shale) are charged via conduits 307, 308 and 309, and are ground, mixed and charged to the kiln through a conduit 310. In a preheat section, these ingredients are contacted counter-currently with hot flue gas, which raises the temperature to drive off water of crystallization and calcine the limestone. Near the bottom of the preheat section, waste combustibles, such as used tires and broken asphalt, are charged through a conduit 311. If necessary to achieve the desired temperature, fuel such as coal, oil or gas is fired, together with combustion air, into the lower part of the preheat section. The preheated mix is then discharged into one end of a horizontal, rotating kiln.
As the preheated ingredients travel to the opposite end of the rotating kiln, they are further heated to the temperature necessary for them to react and form cement clinker by firing, at a discharge end, primary fuel delivered through a conduit 312 (which may include biosolids char), along with the corresponding combustion air supplied via a combustion air fan (not shown) and a conduit 313.
Flue gas, from which most of the sensible heat has been recovered, leaves the kiln via an exhaust fan and dust recovery equipment (not shown) through a line 314. Cement clinker exits the kiln via heat exchange with combustion air, through a conduit 315. The cooled clinker is ground and blended with gypsum to form Portland cement.
Most of the ash constituents of biosolids char are tolerable in Portland cement, with the exception of soluble cations, such as sodium and potassium and the sulfates and chlorides, which go primarily to the effluent from the liquid deoxidation unit and are returned via a conduit 305 to the WWTP. The exception is phosphorus, which often is bound in insoluble form by iron. It is possible that the phosphorus content could limit the amount of biosolids char a given cement kiln can accept. Should the content of phosphorus in the char produced by the unit 301 be so high as to limit the amount of biosolids char that can be accepted in the cement clinker, a chelate solution (or other solubilizing agent) may be employed via a line 316 to extract some of this element. The phosphorus-containing extract is then discharged through a line 317 and must be disposed of in a manner that avoids returning it to the WWTP.
The inorganic fraction of biosolids can be as high as about 50% on a dry basis. This inherent ash found in biosolids can reduce the quantities of limestone, clay and shale input in lines 307, 308 and 309, respectively. If unit 301 is located near the cement kiln 302, a portion of a wastewater stream 305 can be utilized in the cement kiln 302 for cooling or other purposes, or in NOx reduction. Waste heat from the stream 314, or other waste heat streams, including radiation heat, can be utilized by unit 301 as process heat for the system including heating the feed material, process heat, or drying the reacted product. Evolved carbon dioxide from the stream 302 can be conducted to the cement kiln 302 for heat recovery or odor reduction.
Equally as significant as the flow of materials and energy is a flow of money, in the form of tipping fees, from the WWTP to the combination of units 301 and 302, as indicated by the dashed line 318. A portion of the fee goes to the owner of the unit 301, as indicated by a dashed line 319, and the remainder goes to the owner of the cement kiln 302 as indicated by a dashed line 320.
FIG. 4 is a simplified flow diagram of an efficient biosolids processing facility 401 employing deoxidation to convert biosolids into a combustible material in close proximity to and combined with a thermal power station 402. The unit 401 is typified by FIG. 1, charging biosolids from a WWTP. However, since the supply of biosolids available to a station of economic size is unlikely to be sufficient for its fuel needs, it also represents a family of liquid deoxidation processes charging a spectrum of renewable biomass and/or hydrophilic low-rank fossil fuel. With any or all of these potential fuels, liquid deoxidation makes them less hydrophilic and more uniform and thermally efficient for combustion in the power station 402. The station 402 represents a spectrum of conventional and unconventional combustion systems culminating, via steam turbine or gas turbine combined cycles, in the production of electricity for the local market and/or the national grid.
Biosolids are charged to the unit 401 via a line 403. Alternatively or additionally, biomass waste, as paper mill sludge or from agriculture or forestry, is delivered by a transport means 404, and (optionally) hydrophilic low-rank fossil fuel is delivered through a transport means 405. Water as required to form a pumpable charge slurry is added through a line 406. After being processed according to FIG. 1, the now excess water is returned to a WWTP, or treated for discharge by known means, via a line 407. Uniform (dewatered) high energy density char slurry, or dried and pelletized char, is delivered through a transport means 408 to the station 402.
The char or char slurry transported by the transport means 408 is combusted by one of the known methods to yield thermal energy for the generation of steam, which is expanded through conventional steam turbines driving electric generators, or it may be partially oxidized (with either air or commercial oxygen) to yield a fuel gas subsequently burned in a gas turbine combustor driving an electricity generator, the hot exhaust gas from which generates steam for an integrated steam turbine-driven generator. The partial combustion of char may be accomplished according to known processes separating the ash as a fluid slag, or in accordance with U.S. Pat. No. 5,485,728, the entire disclosure of which is incorporated by reference herein, which teaches separation of the ash particles in an aqueous slurry.
Since the amount of char available may have insufficient fuel energy to generate the amount of electricity for which there is a market, supplemental fossil fuel can be supplied via a transport means 410. Air for the combustion or partial combustion of the biomass and/or fossil fuel char is supplied through a line 411. After subjecting it to appropriate known pollution control measures, flue gas (or gases) from the combustion at the station 402 is (are) discharged through a stack 412.
Treated boiler feed water makeup is supplied through a line 413, and blowdown required to maintain boiler water within specifications is discharged via a line 414 to the unit 401, where it may comprise some of the water needed to form a sufficiently fluid feed slurry to the deoxidation operation. Ash, the non-combustible residue from burning the char and auxiliary fuels, or ash slurry, is withdrawn for disposal via a conduit 415.
One of the known methods of controlling the emission of nitrogen oxides from atmospheric pressure boilers is overfiring with a reactive fuel above the main flame zone. Because of its volatiles content and high reactivity, biosolids char is a suitable fuel for this purpose, and a portion of that from the conveying means 408 can be diverted by way of a transport means 416 for nitrogen oxide reduction. The product of the combination, electricity, is delivered from the site via electric cables 417.
For simplification, the biosolids treatment unit 401 is shown as though it had the capacity and raw material supply to furnish the power station 402 with sufficient char fuel. In a practical installation, a treatment unit 401 may be located adjacent to the power station 402, and one or more such units 401 may be installed at other location(s) close to the raw material sources. This gives the operator the flexibility to employ tailored deoxidation temperatures, optimized for the particular feedstock. In such an event, dry char can then be shipped to the power station 402 by road or rail or, if economics dictate, it can be supplied as an aqueous slurry via a pipeline. The flow of money, in the form of a tipping fee, from the WWTP to the deoxidation unit, is indicated by a dashed line 418
FIG. 5 is a simplified flow diagram of a combination comprising a thermal dryer unit 501 and a cement kiln 502. The thermal dryer unit 501 is installed as close as feasible to one or more cement kilns 502, employing principally the same configuration as shown in and described in conjunction with FIG. 3, but without deoxidizing the biosolids. Biosolids are supplied via a transport means 503. By applying heat to the raw biosolids cells, water contained in the cells is evaporated and leaves via a line 505 for scrubbing and condensing or, alternatively, is conducted via a line 517 back to the kiln to be utilized in the kiln as make-up water or for NOx reduction.
The resulting dried biosolids are conducted to the kiln via a line 506 where the Btu value as well as the value of the ash are utilized. The primary ingredients, such as are shown in FIG. 3, are added to the kiln at the lines 507, 508, 509 through a conduit 510. As in FIG. 3, in a preheat section, waste combustibles are added, such as used tires and broken asphalt charged through a conduit 511. As in FIG. 3, combustion air and primary fuel arrive via conduits 513 and 512, respectively. Cement klinker exits the kiln via a conduit 515.
Although thermal drying has an inherent energy penalty from the latent heat in the evaporation of water, this penalty can be entirely or partially overcome by integrating with the cement kiln and utilizing heat from the kiln via a conduit 518. More specifically, flue gas, normally traveling via a conduit 514 to an appropriate discharge, can be directed via a conduit 516 to the thermal dryer, thereby reducing the need for primary fuels at thermal dryer 501 for evaporating the water liberated from the biosolids.
As discussed briefly above, because the potential supply of biosolids char is smaller, by orders of magnitude, than the general fuels market, other substances, for example biomass, can be co-processed in a liquid deoxidation unit, or processed in parallel equipment, and the resulting chars blended before being used as a fuel, for example in accordance with the teachings of U.S. Pat. No. 5,485,728. Several locations, such as Hawaii (biosolids, pineapple and sugar cane wastes) and Sacramento, Calif. (biosolids and rice hulls and stalks), offer sites for slurry co- or parallel deoxidation. Paper mill and paper recycling sludges, although they may require alkali addition to neutralize chlorine, are other promising sources of supplemental hydrophilic biomass. These methods afford a means of consolidating diverse sources into a uniform liquid or solid char slurry fuel.
EXAMPLES
The following examples are only representative of the methods and systems for use in practicing the present invention, and are not to be construed as limiting the scope of the invention in any way.
Example 1
Biosolids from two wastewater treatment plants, one in Atlanta, Ga., and one in Riverside, Calif., were subjected to the earlier described treatment in a continuous pilot plant, resulting in the following feed and product analyses, reported on a moisture and ash-free basis:
Atlanta Raw Riverside Raw
Biosolids Biosolids
Carbon 57.73 62.53
Hydrogen 7.74 9.26
Nitrogen 7.90 7.52
Sulfur 3.02 1.17
Oxygen 23.86 19.52
Total 100.00 100.00
Atlanta Char Riverside Char
Product Product
Carbon 70.19 69.98
Hydrogen 8.85 7.68
Nitrogen 8.63 8.45
Sulfur 1.42 8.86
Oxygen 10.91 5.04
Total 100.00 100.00
As would be expected, the splitting off of carbon dioxide has resulted in an increase in carbon content and a corresponding decrease in oxygen content.
The off-gas composition of the two runs was as follows:
Atlanta Riverside
Off Gas Off Gas
Carbon dioxide 89.7% 92.8%
Volatile organics 10.0% 6.0%
Sulfur compounds 0.3% 1.2%
Total 100.0% 100.0%
Theoretical Example 1
A cement kiln in the southwestern U.S. has a production capacity of 3,200 tons/day. To reach temperatures required to form cement “clinker”, it fires low-grade coal, supplemented to some extent by charging scrap rubber tires. Sensible heat in the flue gas, after preheating mineral charge and combustion air, may be taken advantage of to dry and incinerate 20 tons/day (dry basis) of biosolids from area wastewater treatment plants. Although every ton of dry biosolids constituents is accompanied by about four tons of water (giving the biosolids a negative heating value), revenue from the tipping fee offsets the cost of extra coal that must be fired. However, the amount is limited by the thermal capacity to evaporate the water and by the increased volume of flue gas, increasing pressure drop and fan horsepower.
Using this invention, the kiln may use biosolids dewatered and deoxidized in accordance with the present invention at one or more of the nearby WWTPs. As such, about 80% to 94% of the water formerly charged with the raw biosolids bypasses the kiln, permitting it to charge seven times as much deoxidized material without exceeding thermal capacity and fan horsepower limits. The biosolids disposed of by the kiln can be increased by a factor of about 700%, with a corresponding increase in tipping fees.
Other than in the operating examples, or unless otherwise expressly specified, all of the numerical ranges, amounts, values and percentages such as those for amounts of materials, times and temperatures of reaction, ratios of amounts, and others in the following portion of the specification may be read as if prefaced by the word “about” even though the term “about” may not expressly appear with the value, amount or range. Accordingly, unless indicated to the contrary, the numerical parameters set forth in the following specification and attached claims are approximations that may vary depending upon the desired properties sought to be obtained by the present invention.
Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the invention are approximations, the numerical values set forth in the specific examples are reported as precisely as possible. Any numerical value, however, inherently contains certain errors necessarily resulting from the standard deviation found in their respective testing measurements. Furthermore, when numerical ranges of varying scope are set forth herein, it is contemplated that any combination of these values inclusive of the recited values may be used.
The invention described and claimed herein is not to be limited in scope by the specific embodiments herein disclosed, since these embodiments are intended as illustrations of several aspects of the invention. Any equivalent embodiments are intended to be within the scope of this invention. Indeed, various modifications of the invention in addition to those shown and described herein will become apparent to those skilled in the art from the foregoing description. Such modifications are also intended to fall within the scope of the appended claims. All patents and patent applications cited in the foregoing text are expressly incorporated herein by reference in their entirety.

Claims (27)

What is claimed is:
1. A process of converting biomass into a renewable fuel comprising the steps of:
providing biomass comprising at least about 10% water;
slurrying the biomass by performing at least one of the steps of grinding and adding at least one of fresh water, recycled water, steam, and a combination thereof to form a pumpable slurry;
applying sufficient pressure to the biomass slurry to maintain liquidity and form pressurized biomass;
heating the pressurized biomass to a first temperature, wherein the first temperature is sufficient to form an aqueous char slurry, carbon dioxide, and free water;
depressurizing the biomass char slurry;
separating the carbon dioxide from the biomass char slurry;
removing at least a portion of the free water from the biomass char slurry to provide a dewatered biomass char product containing a decreased oxygen content;
drying a portion of the dewatered biomass char product to remove more of the free water and to provide a dried biomass char product;
providing a first output of the dewatered biomass char product; and
providing a second output of the dried biomass char product.
2. The process of claim 1, wherein the biomass comprises sewage sludge.
3. The process of claim 1, further comprising the steps of:
reacting the dewatered biomass char product with a gas comprising oxygen to thereby convert its fuel value into thermal energy; and
using the thermal energy.
4. The process of claim 1, wherein the first temperature is between about 200° C. and 345° C. (400° F. and 650° F.).
5. The process of claim 1, further comprising the step of adding an agent for dissolution of at least one polluting or slag-forming element present in the dewatered biomass char product.
6. The process of claim 5, wherein the agent comprises an alkali.
7. The process of claim 1, wherein a portion of the freed water is recycled to the adding step.
8. The process of claim 1, wherein the drying step comprises substantially removing water from the dewatered biomass char product as steam.
9. The process of claim 1, further comprising the step of cooling the aqueous char slurry to a second temperature less than the first temperature.
10. The process of claim 9, wherein the second temperature is about 40° C. to 90° C. (100° F. to 200° F.).
11. The process of claim 1, further comprising the step of discharging the carbon dioxide through a flame of at least one of an oxidizer and a process heater.
12. The process of claim 1, wherein process water from an adjacent wastewater treatment plant is used in the slurrying step.
13. The process of claim 1, further comprising the step of pretreating at least a portion of the free water to form pretreated water and recycling the pretreated water to an adjacent wastewater treatment plant.
14. The process of claim 1, further comprising the step of using a digester gas from an adjacent wastewater treatment plant as fuel for the heating step.
15. The process of claim 1, wherein the first output of the dewatered biomass char product has a higher moisture content than the second output of the dried biomass char product.
16. A process of converting a slurry of biosolids into a combustible fuel comprising the steps of:
providing biosolids comprising at least about 10% water in a feed slurry;
applying sufficient pressure to the feed slurry to maintain liquidity and form pressurized feed slurry;
heating the pressurized feed slurry in a reactor-stripper tower to a sufficient temperature for cell rupture to form an aqueous char slurry, stripped carbon dioxide, and free water, the pressurized feed slurry flowing downwardly through the reactor-stripper tower to contract steam and the stripped carbon dioxide flowing upwardly through the reactor-stripper tower;
depressurizing the aqueous char slurry;
separating the stripped carbon dioxide from the aqueous char slurry; and
removing at least a portion of the free water from the aqueous char slurry to provide a dewatered char product.
17. The process of claim 16, wherein the aqueous char slurry exits from a base of the reactor-stripper tower, and the steam and the stripped carbon dioxide exit from a top of the reactor-stripper tower.
18. The process of claim 17, further comprising separating the stripped carbon dioxide from the steam by condensing the steam to distilled water.
19. The process of claim 16, wherein the reactor-stripper tower has a top-to-bottom temperature gradient from about 200° C. (400° F.) to about 260° C. (500° F.).
20. The process of claim 16, wherein the reactor-stripper tower has a top-to-bottom temperature gradient from about 150° C. (300° F.) to about 315° C. (600° F.).
21. A process of converting a slurry of a combination of at least one of a biosolids and low-rank fossil fuels fuel into a combustible fuel comprising the steps of:
providing biosolids comprising at least about 10% water;
providing low-rank fossil fuel;
mixing the biosolids and low-rank fossil fuel to form a feed slurry;
applying sufficient pressure to the feed slurry to maintain liquidity and form pressurized feed slurry;
heating the pressurized feed slurry to a sufficient temperature for cell rupture to form an aqueous char slurry comprising carbon dioxide and free water;
depressurizing the aqueous char slurry;
separating the carbon dioxide from the aqueous char slurry; and
removing at least a portion of the free water from the aqueous char slurry to provide a dewatered char product, wherein the removing step comprises adding at least one polymer to enhance separation of the free water from the aqueous char slurry.
22. The process of claim 21, wherein said applying step further comprises injecting steam into the slurry.
23. A process of converting a slurry of a combination of at least one of a biosolids and low-rank fossil fuels fuel into a combustible fuel comprising the steps of:
providing biosolids comprising at least about 10% water;
providing low-rank fossil fuel;
mixing the biosolids and low-rank fossil fuel to form a feed slurry;
applying sufficient pressure to the feed slurry to maintain liquidity and form pressurized feed slurry;
heating the pressurized feed slurry to a sufficient temperature for cell rupture to form an aqueous char slurry comprising carbon dioxide and free water;
depressurizing the aqueous char slurry;
separating the carbon dioxide from the aqueous char slurry; and
removing at least a portion of the free water from the aqueous char slurry to provide a dewatered char product,
wherein, prior to the depressurizing step, a portion of the char slurry is recycled back to the heated, pressurized biosolids.
24. A method of converting sewage sludge comprising biosolids including cell-bound water into a product having a positive fuel value comprising:
receiving a first biosolids feed from a first source;
receiving a second biosolids feed from a second source, wherein the first biosolids feed is more dilute than the second biosolids feed and the second biosolids feed is more viscous than the first biosolids feed;
mixing the first and second biosolids feeds to produce a pumpable biosolids feed;
rupturing the biosolids cells in the pumpable biosolids feed to free the water bound therein;
subjecting the ruptured biosolids cells to sufficient temperature to convert the ruptured biosolids cells into char; and
removing at least a portion of the water from the slurry to form a char product adapted to be combusted at an elevated temperature.
25. The method of claim 24, further comprising the step of suspending the ruptured biosolids cells in at least the water freed from the biosolids cells.
26. The method of claim 24, wherein the pumpable biosolids feed has a solids concentration of about 3% to 40%.
27. The method of claim 26, wherein the pumpable biosolids feed has a solids concentration of about 3% to 20%.
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Families Citing this family (113)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7024796B2 (en) 2004-07-19 2006-04-11 Earthrenew, Inc. Process and apparatus for manufacture of fertilizer products from manure and sewage
US7024800B2 (en) * 2004-07-19 2006-04-11 Earthrenew, Inc. Process and system for drying and heat treating materials
US7685737B2 (en) 2004-07-19 2010-03-30 Earthrenew, Inc. Process and system for drying and heat treating materials
US7694523B2 (en) 2004-07-19 2010-04-13 Earthrenew, Inc. Control system for gas turbine in material treatment unit
US7909895B2 (en) 2004-11-10 2011-03-22 Enertech Environmental, Inc. Slurry dewatering and conversion of biosolids to a renewable fuel
US8043505B2 (en) 2005-04-27 2011-10-25 Enertech Environmental, Inc. Treatment equipment of organic waste and treatment method
US7610692B2 (en) * 2006-01-18 2009-11-03 Earthrenew, Inc. Systems for prevention of HAP emissions and for efficient drying/dehydration processes
US7942942B2 (en) * 2006-05-21 2011-05-17 Paoluccio John A Method and apparatus for biomass torrefaction, manufacturing a storable fuel from biomass and producing offsets for the combustion products of fossil fuels and a combustible article of manufacture
US8323923B1 (en) 2006-10-13 2012-12-04 Sweetwater Energy, Inc. Method and system for producing ethanol
US9499635B2 (en) 2006-10-13 2016-11-22 Sweetwater Energy, Inc. Integrated wood processing and sugar production
DE102006061217B3 (en) * 2006-12-22 2008-06-05 Buchert, Jürgen Processing clarified sludge to produce fuel, e.g. for electricity generation, by mixing with biomass, thermally cracking and fluidizing, gasifying and condensing gasified product
DE102007056170A1 (en) * 2006-12-28 2008-11-06 Dominik Peus Substance or fuel for producing energy from biomass, is manufactured from biomass, which has higher carbon portion in comparison to raw material concerning percentaged mass portion of elements
US7485230B2 (en) * 2007-02-28 2009-02-03 Magner Joseph A Integrated cogeneration wastewater sewage and waste polar fats/ oils/ greases/waxes (FOG) waste treatment method and facility
CZ300446B6 (en) 2007-04-27 2009-05-20 Jihoceská univerzita v Ceských Budejovicích, Zemedelská fakulta Method of treatment of iron-containing waterworks sludge and a mixture prepared by this method
EP2142451B1 (en) * 2007-04-27 2012-06-20 Enertech Environmental, Inc. Disposal of slurry in underground geologic formations
US20090031698A1 (en) * 2007-07-31 2009-02-05 O'brien & Gere Engineers Inc. Liquid and Solid Biofueled Combined Heat and Renewable Power Plants
CN101376813B (en) * 2007-08-28 2011-12-21 三菱重工业株式会社 Carbonizing processing method and apparatus for high water-bearing organic
JP4959604B2 (en) * 2008-02-28 2012-06-27 中国電力株式会社 Slurry production method and slurry production system
US20100146848A1 (en) * 2008-03-27 2010-06-17 Ian Fraser Johnston Fuel formed of cellulosic and biosolid materials
MX2010014190A (en) 2008-06-26 2011-03-29 Casella Waste Systems Inc Star Engineered fuel feed stock.
PL2300575T3 (en) * 2008-06-26 2017-09-29 Accordant Energy, Llc Engineered fuel feed stock useful for displacement of coal in coal firing plants
US8444721B2 (en) 2008-06-26 2013-05-21 Re Community Energy, Llc Engineered fuel feed stock
WO2009158709A2 (en) * 2008-06-28 2009-12-30 White Ken W Powdered fuel production methods and systems useful in farm to flame systems
CA2729802C (en) 2008-07-02 2013-06-11 Ciris Energy, Inc. Method for optimizing in-situ bioconversion of carbon-bearing formations
US9194582B2 (en) * 2008-07-14 2015-11-24 Cake Energy, Llc Energy recovery and transfer system and process
WO2010068637A1 (en) * 2008-12-09 2010-06-17 Jerry Wayne Horton Ensiling biomass and multiple phase apparatus for hydrolyzation of ensiled biomass
WO2010089735A1 (en) * 2009-02-05 2010-08-12 Applied Cleantech Inc. Methods and systems for gaseous emission reduction from sewage management systems
US20100206499A1 (en) * 2009-02-13 2010-08-19 Zilkha Biomass Acquisitions Company L.L.C. Methods for Producing Biomass-Based Fuel With Pulp Processing Equipment
DE102009014776A1 (en) * 2009-03-25 2010-09-30 Mcb Gmbh Apparatus and method for the thermal hydrolysis of organic matter
US8915981B2 (en) * 2009-04-07 2014-12-23 Gas Technology Institute Method for producing methane from biomass
WO2010123141A1 (en) * 2009-04-22 2010-10-28 Jfeスチール株式会社 Method for washing biomass, method for producing biomass charcoal and method for operating vertical furnace
KR101024969B1 (en) 2009-05-28 2011-03-30 주식회사 에코에너지홀딩스 Pre-treatment System for landfill gas of waste landfill
US20140001121A1 (en) * 2012-04-18 2014-01-02 Gene F. DeShazo Method for Reclaiming Usable Products from Biosolids
US8100989B2 (en) * 2009-11-01 2012-01-24 Kunik Burton J Method and system of making a burnable fuel
EP2504625A4 (en) * 2009-11-24 2014-03-12 Jasper Gmbh Waste to energy by way of hydrothermal decomposition and resource recycling
WO2011066393A2 (en) 2009-11-25 2011-06-03 Ghd, Inc. Biosolids digester and process for biosolids production
SG181644A1 (en) 2009-12-18 2012-07-30 Ciris Energy Inc Biogasification of coal to methane and other useful products
CA2790678A1 (en) 2009-12-22 2011-06-30 Re Community Energy, Llc Sorbent containing engineered fuel feed stocks
AT509221B1 (en) * 2009-12-28 2011-07-15 Holcim Technology Ltd METHOD FOR ASSESSING PHOSPHORUS-BASED ALTERNATIVE FUELS IN CEMENT MANUFACTURE
US8163045B2 (en) * 2009-12-29 2012-04-24 Sharps Compliance, Inc Method and system of making a burnable fuel
US8268073B2 (en) * 2009-12-29 2012-09-18 Sharps Compliance, Inc. System and method for making cement and cement derived therefrom
TW201202152A (en) 2010-03-23 2012-01-16 Univ Utah Res Found Methods for deactivating biomass
CN101880564A (en) * 2010-06-28 2010-11-10 聂晓明 Sludge biomass synthetic fuel and preparation method thereof
DE102010017635A1 (en) 2010-06-29 2011-12-29 G+R Technology Group Ag Recycling system and method for operating a recycling system
TWI421220B (en) * 2010-08-12 2014-01-01 South China Reborn Resources Zhongshan Co Ltd Method for transforming sewage sludge in cities into gas, liquid, and solid fuel under fully closed equipment system
US8408840B2 (en) 2010-08-31 2013-04-02 Dennis Dillard Aerobic irrigation controller
RU2447045C1 (en) * 2010-10-26 2012-04-10 Андрей Николаевич Ульянов Method and unit for poultry manure processing
EP2640522A1 (en) * 2010-11-16 2013-09-25 Celitron Medical Technologies System and methods for conversion of biohazard to municipal waste
WO2012085860A1 (en) * 2010-12-21 2012-06-28 Inbicon A/S Steam delivery system for biomass processing
ITMI20110333A1 (en) * 2011-03-03 2012-09-04 Eni Spa INTEGRATED PROCEDURE FOR THE PRODUCTION OF BIO-OIL FROM SLUDGE ARISING FROM A WASTEWATER TREATMENT PLANT.
CN102173555B (en) * 2011-03-16 2012-07-04 上海伏波环保设备有限公司 Boiler unit steam extraction and drying sludge system with thermal compensation
KR20120109378A (en) * 2011-03-25 2012-10-08 (주)에이피더블유 Method for solidifying sludge, solid manufactured by thereof, industrial materials and solid fuel using the same
RU2460695C1 (en) * 2011-04-07 2012-09-10 Общество с ограниченной ответственностью "Межрегиональный центр биологических и химических технологий" Plant for obtaining biogas, electric and heat energy and fertilisers from agricultural wastes
RU2469968C1 (en) * 2011-06-08 2012-12-20 Общество с ограниченной ответственностью "УралЭкоМет" Crude mixture for synthesis of sulphated cement
US8329455B2 (en) 2011-07-08 2012-12-11 Aikan North America, Inc. Systems and methods for digestion of solid waste
US8834834B2 (en) * 2011-07-21 2014-09-16 Enerkem, Inc. Use of char particles in the production of synthesis gas and in hydrocarbon reforming
RU2475677C1 (en) * 2011-09-13 2013-02-20 Дмитрий Львович Астановский Method of processing solid household and industrial wastes using synthesis gas
US20130125455A1 (en) * 2011-10-25 2013-05-23 Point Source Power, Inc. Fuel block for high temperature electrochemical device
PT2807238T (en) 2012-01-26 2018-10-23 Accordant Energy Llc Mitigation of harmful combustion emissions using sorbent containing fuel feedstocks
US8765430B2 (en) 2012-02-10 2014-07-01 Sweetwater Energy, Inc. Enhancing fermentation of starch- and sugar-based feedstocks
TWI381143B (en) * 2012-03-02 2013-01-01 Taiwan Clean Energy Technology Co Ltd Material Heat Treatment Separation and Energy Recovery System
US8563277B1 (en) 2012-04-13 2013-10-22 Sweetwater Energy, Inc. Methods and systems for saccharification of biomass
US9222040B2 (en) * 2012-06-07 2015-12-29 General Electric Company System and method for slurry handling
FI124553B (en) 2012-07-11 2014-10-15 Bln Woods Ltd Ab A method for extracting biomass
US9534174B2 (en) 2012-07-27 2017-01-03 Anellotech, Inc. Fast catalytic pyrolysis with recycle of side products
US10018416B2 (en) 2012-12-04 2018-07-10 General Electric Company System and method for removal of liquid from a solids flow
NZ743055A (en) 2013-03-08 2020-03-27 Xyleco Inc Equipment protecting enclosures
US9651304B1 (en) 2013-03-14 2017-05-16 Green Recovery Technologies, LLC Pretreatment of biomass prior to separation of saturated biomass
CA2906917A1 (en) 2013-03-15 2014-09-18 Sweetwater Energy, Inc. Carbon purification of concentrated sugar streams derived from pretreated biomass
US10131846B2 (en) * 2013-06-12 2018-11-20 Cri Co., Ltd Apparatus and method for supplying continuous heat/pressure to continuously feed and discharge heated/pressurized oil shale sludge in kerogen extraction reactor
FR3008693B1 (en) 2013-07-18 2019-05-03 Terranova Energy Gmbh OPTIMIZED HYDROTHERMAL CARBONIZATION PROCESS AND INSTALLATION FOR ITS IMPLEMENTATION
US9102885B2 (en) * 2013-07-26 2015-08-11 Renmatix, Inc. Method of transporting viscous slurries
CA2917128A1 (en) * 2013-07-26 2015-01-29 Renmatix, Inc. Method of transporting viscous slurries
US20160185641A1 (en) * 2013-07-31 2016-06-30 SGC Advisors, LLC Mobile thermal treatment method for processing organic material
WO2015026875A1 (en) * 2013-08-19 2015-02-26 Paul Koenig Waste processing system
CA2927127C (en) * 2013-10-13 2023-08-22 Cornerstone Resources, Llc Methods and apparatus utilizing vacuum for breaking organic cell walls
US20160264444A1 (en) * 2013-11-04 2016-09-15 SGC Advisors, LLC Thermal treatment system and method for efficient processing of organic material
US9784121B2 (en) 2013-12-11 2017-10-10 General Electric Company System and method for continuous solids slurry depressurization
US9702372B2 (en) 2013-12-11 2017-07-11 General Electric Company System and method for continuous solids slurry depressurization
CN103881779B (en) * 2014-03-24 2015-06-03 北京三益能源环保发展股份有限公司 Methane membrane method purification and heating system
CN104195035B (en) * 2014-09-15 2016-01-13 青岛中科华通能源工程有限公司 Biogas engineering waste heat comprehensive utilization system
CN107002358B (en) * 2014-10-15 2020-01-14 康福木浆有限公司 Integrated kraft pulp mill and thermochemical conversion system
FR3027894B1 (en) * 2014-11-04 2019-05-24 Degremont METHOD FOR HYDROTHERMAL CARBONIZATION OF BIOMASS, AND DEVICE THEREFOR
FR3027914B1 (en) 2014-11-04 2018-05-04 Terranova Energy Gmbh METHOD FOR HYDROTHERMAL CARBONIZATION OF BIOMASS, AND DEVICE THEREFOR
PL3230463T3 (en) 2014-12-09 2022-10-03 Sweetwater Energy, Inc. Rapid pretreatment
GB2536132B (en) * 2015-03-02 2017-05-24 Veolia Water Solutions & Tech System and method for treating wastewater and resulting primary and biological sludge
KR101722698B1 (en) * 2015-05-29 2017-04-11 에스씨에코 주식회사 High calorific power fuel, apparatus and method for manufacturing the same for thermoelectric power plant and steelworks using palm oil by-product and wooden biomass
TN2017000518A1 (en) * 2015-06-10 2019-04-12 Brisa Int Llc System and method for biomass growth and processing
CN105253888B (en) * 2015-10-27 2017-12-22 昆明理工大学 A kind of method for improving smelting industrial silicon biomass carbon reducing agent ratio resistance
LU92916B1 (en) * 2015-12-17 2017-07-13 Wurth Paul Sa Grinding and drying plant
US10415825B2 (en) * 2016-06-07 2019-09-17 The Babcock & Wilcox Company Methods of generating energy from cellulosic biofuel waste
US10689282B2 (en) * 2016-10-27 2020-06-23 The University Of Western Ontario Hydrothermal liquefaction co-processing of wastewater sludge and lignocellulosic biomass for co-production of bio-gas and bio-oils
CN108395040B (en) * 2017-02-05 2021-07-02 鞍钢股份有限公司 Preparation method of waste heat boiler make-up water
CA3053773A1 (en) 2017-02-16 2018-08-23 Sweetwater Energy, Inc. High pressure zone formation for pretreatment
ES2797113T3 (en) 2017-02-20 2020-12-01 Htcycle Ag Procedure to carry out a hydrothermal carbonization reaction
DK3372657T3 (en) 2017-03-10 2020-01-27 Htcycle Gmbh DEVICE FOR PERFORMING A HYDROTERMIC CARBONIZATION REACTION
US10723956B2 (en) 2017-07-21 2020-07-28 1888711 Alberta Inc. Enhanced distillate oil recovery from thermal processing and catalytic cracking of biomass slurry
CN108358421B (en) * 2018-02-02 2020-10-30 华中科技大学 Method for simultaneously removing water from sludge and preparing solid fuel and product
RU2678089C1 (en) * 2018-02-06 2019-01-23 Общество с ограниченной ответственностью "ПРОМЕТЕЙ" Industrial complex for the production of charcoal without waste method of low-temperature pyrolysis from briquette wood waste
US10927014B1 (en) * 2018-06-06 2021-02-23 Raymond C. Sherry Waste water treatment to reduce BOD/COD
KR102171486B1 (en) * 2018-11-13 2020-10-29 주식회사 티에스케이엔지니어링 Method of Manufacturing Solid Fuel using Food Waste
WO2020141967A1 (en) * 2019-01-03 2020-07-09 Palmite Process Engineering Sdn Bhd Method for converting palm oil mill liquid effluent to a solid biomass to facilitate recycling
CN110436730A (en) * 2019-08-21 2019-11-12 东华工程科技股份有限公司 A kind of sludge drying pyrolysis system and technique processing method
US11692000B2 (en) 2019-12-22 2023-07-04 Apalta Patents OÜ Methods of making specialized lignin and lignin products from biomass
US11279882B2 (en) 2020-01-10 2022-03-22 Battelle Memorial Institute Hydrothermal liquefaction system
CN111423095B (en) * 2020-03-05 2022-04-08 厦门大学 Method for treating residual activated sludge
CN111676076B (en) * 2020-04-27 2021-06-18 吉林宏日新能源股份有限公司 Coupling method and system for ecological utilization and energy utilization of biomass resources
US11578278B2 (en) * 2020-08-01 2023-02-14 Honeywell International Inc. Renewable transportation fuel process with thermal oxidation system
CN111778082A (en) * 2020-08-13 2020-10-16 李奕萱 Preparation method for preparing solid fuel by using household garbage
CN112845504B (en) * 2020-12-24 2022-06-21 南京绿帝环保能源科技有限公司 Household garbage resource utilization treatment process
KR102357549B1 (en) * 2021-04-22 2022-02-09 (주)키나바 Method for producing solid fuel that reduces odor by using hydrothermal carbonization of organic or inorganic waste, and solid fuel produced by the method
CN113956893B (en) * 2021-10-13 2023-12-12 昆明理工大学 Preparation method and application of biomass carbon rod
CN116354570B (en) * 2023-05-31 2023-08-15 国能龙源环保有限公司 Cooperative treatment system and method for power plant wastewater and oil sludge

Citations (159)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3580193A (en) 1969-09-05 1971-05-25 Dorr Oliver Inc Heat treated waste sludge disposal
US3729042A (en) 1971-02-22 1973-04-24 Pollutant Separation Inc Apparatus for separating pollutants and obtaining separate liquids & solids
US3830636A (en) 1970-02-26 1974-08-20 Black Clawson Fibreclaim Inc Fuel by-products of municipal refuse
US3853759A (en) 1968-06-06 1974-12-10 J Titmas Dynamic hydraulic column activation method
US4017421A (en) 1975-12-16 1977-04-12 Othmer Donald F Wet combustion process
US4038152A (en) 1975-04-11 1977-07-26 Wallace-Atkins Oil Corporation Process and apparatus for the destructive distillation of waste material
US4087276A (en) 1975-05-05 1978-05-02 Anic S.P.A. Removal of mercury from sludge by heating and condensing
US4126519A (en) 1977-09-12 1978-11-21 Edward Koppelman Apparatus and method for thermal treatment of organic carbonaceous material
US4128946A (en) 1977-03-08 1978-12-12 Uop Inc. Organic waste drying process
US4192653A (en) 1977-12-29 1980-03-11 Gulf Research And Development Company Novel fuel compositions comprising upgraded solid _and/or semi-solid material prepared from coal
US4208245A (en) 1977-02-03 1980-06-17 St. Regis Paper Company Pyrolysis of spent pulping liquors
US4229296A (en) 1978-08-03 1980-10-21 Whirlpool Corporation Wet oxidation system employing phase separating reactor
US4241722A (en) 1978-10-02 1980-12-30 Dickinson Norman L Pollutant-free low temperature combustion process having carbonaceous fuel suspended in alkaline aqueous solution
US4255129A (en) 1979-07-11 1981-03-10 Thomas N. DePew Apparatus and method for processing organic materials into more useful states
US4272322A (en) 1978-04-03 1981-06-09 Masahiro Kobayashi Method for manufacturing charcoals from paper sludge
US4284015A (en) 1979-03-26 1981-08-18 Dickinson Norman L Pollution-free coal combustion process
US4292953A (en) 1978-10-05 1981-10-06 Dickinson Norman L Pollutant-free low temperature slurry combustion process utilizing the super-critical state
US4377066A (en) 1980-05-27 1983-03-22 Dickinson Norman L Pollution-free pressurized fluidized bed combustion utilizing a high concentration of water vapor
US4380960A (en) 1978-10-05 1983-04-26 Dickinson Norman L Pollution-free low temperature slurry combustion process utilizing the super-critical state
US4414813A (en) 1981-06-24 1983-11-15 Knapp Hans J Power generator system
US4477257A (en) 1982-12-13 1984-10-16 K-Fuel/Koppelman Patent Licensing Trust Apparatus and process for thermal treatment of organic carbonaceous materials
US4486959A (en) 1983-12-27 1984-12-11 The Halcon Sd Group, Inc. Process for the thermal dewatering of young coals
US4579562A (en) 1984-05-16 1986-04-01 Institute Of Gas Technology Thermochemical beneficiation of low rank coals
US4593202A (en) 1981-05-06 1986-06-03 Dipac Associates Combination of supercritical wet combustion and compressed air energy storage
US4615711A (en) 1982-11-26 1986-10-07 Mueller Dietrich Sewage sludge fuel briquette
US4618735A (en) 1983-09-13 1986-10-21 Canadian Patents And Development Limited Process and apparatus for the conversion of sludges
US4657681A (en) 1985-04-22 1987-04-14 Hughes William L Method of converting organic material into useful products and disposable waste
US4702745A (en) 1985-05-02 1987-10-27 Kawasaki Jukogyo Kabushiki Kaisha Process for dewatering high moisture, porous organic solid
US4714032A (en) 1985-12-26 1987-12-22 Dipac Associates Pollution-free pressurized combustion utilizing a controlled concentration of water vapor
US4721575A (en) 1986-04-03 1988-01-26 Vertech Treatment Systems, Inc. Method and apparatus for controlled chemical reactions
US4735729A (en) 1986-06-20 1988-04-05 Zimpro Inc. Ash concentration and disposal method
US4762527A (en) 1986-12-16 1988-08-09 Electric Fuels Corporation Slurry fuel comprised of a heat treated, partially dewatered sludge with a particulate solid fuel and its method of manufacture
US4761893A (en) 1986-10-29 1988-08-09 Glorioso John D Sludge treatment process
US4765911A (en) 1987-09-14 1988-08-23 North American Metals, Inc. Process for treating municipal wastewater sludge
US4795568A (en) 1987-06-03 1989-01-03 Chen Philip T Oxidative evaporation process and apparatus
US4824561A (en) 1986-12-18 1989-04-25 Basf Corporation Wastewater treatment
US4829678A (en) 1986-10-29 1989-05-16 Enviro Gro Technologies Sludge treatment process
US4852269A (en) 1986-10-29 1989-08-01 Enviro-Gro Technologies, Inc. Combined sewage and lime slude treatment process
US4860671A (en) 1986-10-29 1989-08-29 Enviro-Gro Technologies, Inc. Odor control for a sludge treatment process
US4869833A (en) 1986-04-03 1989-09-26 Vertech Treatment Systems, Inc. Method and apparatus for controlled chemical reactions
US4875905A (en) 1988-11-14 1989-10-24 Solidiwaste Technology, L.P. Method of preparing a high heating value fuel product
US4898107A (en) 1985-12-26 1990-02-06 Dipac Associates Pressurized wet combustion of wastes in the vapor phase
US4909899A (en) 1986-09-22 1990-03-20 A. Ahlstrom Corporation Method of concentrating sludges
US4915706A (en) 1985-05-10 1990-04-10 Daley Ralph D Coal-water fuel production
US4922841A (en) 1988-09-14 1990-05-08 Kent John M Method and apparatus for using hazardous waste to form non-hazardous aggregate
US4953478A (en) 1986-10-29 1990-09-04 Enviro-Gro Technologies Odor control for a sludge treatment process
US4956926A (en) 1986-10-29 1990-09-18 Enviro-Gro Technologies Sludge treatment process
US4983782A (en) 1988-02-27 1991-01-08 Veba Oel Entwicklungs-Gesellschaft Mbh Process for treating wastes and the like by low temperature carbonization and further processing of the low temperature carbonization oil
US4983296A (en) 1989-08-03 1991-01-08 Texaco Inc. Partial oxidation of sewage sludge
US5000099A (en) 1985-12-26 1991-03-19 Dipac Associates Combination of fuels conversion and pressurized wet combustion
US5009767A (en) 1988-02-02 1991-04-23 Mobil Oil Corporation Recycle of oily refinery wastes
US5019135A (en) 1987-10-13 1991-05-28 Battelle Memorial Institute Method for the catalytic conversion of lignocellulosic materials
US5018456A (en) 1989-02-24 1991-05-28 Williams Patent Crusher And Pulverizer Company System for disposing of sludge
US5050375A (en) 1985-12-26 1991-09-24 Dipac Associates Pressurized wet combustion at increased temperature
US5057231A (en) 1990-11-08 1991-10-15 Zimpro Passavant Environmental Systems, Inc. Method for starting up and controlling operating temperature of a wet oxidation process
US5075015A (en) 1991-05-01 1991-12-24 Zimpro Passavant Environmental Systems, Inc. Method for color removal from thermally conditioned sludge liquors
EP0328574B1 (en) 1987-07-14 1992-01-08 Fhj Process B.V. Process for the conversion and working up of a mixture of organic matter, anorganic matter and water to a nearly dry product, as well as an installation for the execution of the process and application thereof by the conversion of manure slurry
US5082571A (en) 1991-05-13 1992-01-21 Zimpro Passavant Environmental Systems Inc. Caustic sulfide wet oxidation process
US5087370A (en) 1990-12-07 1992-02-11 Clean Harbors, Inc. Method and apparatus to detoxify aqueous based hazardous waste
US5087378A (en) 1990-05-31 1992-02-11 Pori, International, Inc. Process for enhancing the dewaterability of waste sludge from microbiological digestion
US5114541A (en) 1980-11-14 1992-05-19 Ernst Bayer Process for producing solid, liquid and gaseous fuels from organic starting material
US5132007A (en) 1987-06-08 1992-07-21 Carbon Fuels Corporation Co-generation system for co-producing clean, coal-based fuels and electricity
US5183577A (en) 1992-01-06 1993-02-02 Zimpro Passavant Environmental Systems, Inc. Process for treatment of wastewater containing inorganic ammonium salts
US5188741A (en) 1992-04-01 1993-02-23 Texaco Inc. Treatment of sewage sludge
US5188740A (en) 1991-12-02 1993-02-23 Texaco Inc. Process for producing pumpable fuel slurry of sewage sludge and low grade solid carbonaceous fuel
US5188739A (en) 1991-12-02 1993-02-23 Texaco Inc. Disposal of sewage sludge
EP0377832B1 (en) 1988-12-13 1993-03-10 Thyssen Still Otto Anlagentechnik GmbH Process for the treatment of biomasses, e.g. sewage sludge, manure, etc.
US5205906A (en) 1988-08-08 1993-04-27 Chemical Waste Management, Inc. Process for the catalytic treatment of wastewater
US5211723A (en) 1991-09-19 1993-05-18 Texaco Inc. Process for reacting pumpable high solids sewage sludge slurry
US5211724A (en) 1991-04-15 1993-05-18 Texaco, Inc. Partial oxidation of sewage sludge
US5217625A (en) 1992-10-02 1993-06-08 Texaco Inc. Process for disposing of sewage sludge
US5230211A (en) 1991-04-15 1993-07-27 Texaco Inc. Partial oxidation of sewage sludge
US5230810A (en) 1991-09-25 1993-07-27 Zimpro Passavant Environmental Systems, Inc. Corrosion control for wet oxidation systems
US5234607A (en) 1992-04-22 1993-08-10 Zimpro Passavant Environment Systems Inc. Wet oxidation system startup process
US5234469A (en) 1991-06-28 1993-08-10 Texaco Inc. Process for disposing of sewage sludge
US5234468A (en) 1991-06-28 1993-08-10 Texaco Inc. Process for utilizing a pumpable fuel from highly dewatered sewage sludge
US5240619A (en) 1993-02-11 1993-08-31 Zimpro Passavant Environmental Systems, Inc. Two-stage subcritical-supercritical wet oxidation
US5264009A (en) 1992-09-01 1993-11-23 Texaco Inc. Processing of sewage sludge for use as a fuel
US5266085A (en) 1991-09-19 1993-11-30 Texaco Inc. Process for disposing of sewage sludge
US5273556A (en) 1992-03-30 1993-12-28 Texaco Inc. Process for disposing of sewage sludge
US5280701A (en) 1992-08-31 1994-01-25 Environmental Energy Systems, Inc. Waste treatment system and method utilizing pressurized fluid
US5288413A (en) 1991-10-24 1994-02-22 Shell Oil Company Treatment of a waste sludge to produce a non-sticking fuel
US5292442A (en) * 1992-10-01 1994-03-08 Texaco Inc. Process for disposing of sewage sludge
US5292429A (en) 1989-11-29 1994-03-08 Seaview Thermal Systems Process for recovery and treatment of a diverse waste stream
US5349910A (en) 1992-08-06 1994-09-27 F. L. Smidth & Co. A/S Method and apparatus for incinerating waste in a cement kiln plant
US5356540A (en) 1991-05-20 1994-10-18 Texaco Inc. Pumpable aqueous slurries of sewage sludge
US5370715A (en) 1993-04-27 1994-12-06 Kortzeborn; Robert N. Waste destructor and method of converting wastes to fluid fuel
US5389259A (en) 1992-08-24 1995-02-14 Zimpro Environmental Inc. Preparation treatment of volatile wastewater components
US5389264A (en) 1993-07-12 1995-02-14 Zimpro Environmental Inc. Hydraulic energy dissipator for wet oxidation process
US5485728A (en) * 1985-12-26 1996-01-23 Enertech Environmental, Inc. Efficient utilization of chlorine and moisture-containing fuels
US5500044A (en) 1993-10-15 1996-03-19 Greengrove Corporation Process for forming aggregate; and product
US5582793A (en) 1991-10-03 1996-12-10 Antaeus Group, Inc. Process for treating waste material
US5586510A (en) 1994-03-16 1996-12-24 Cement Industry Environment Consortium Method and system for controlling pollutant emissions in combustion operations
US5630854A (en) 1982-05-20 1997-05-20 Battelle Memorial Institute Method for catalytic destruction of organic materials
US5641413A (en) 1995-10-27 1997-06-24 Zimpro Environmental, Inc. Removal of nitrogen from wastewaters
US5685153A (en) 1985-12-26 1997-11-11 Enertech Environmental, Inc. Efficient utilization of chlorine and/or moisture-containing fuels and wastes
US5707417A (en) 1994-09-30 1998-01-13 Director-General Of Agency Of Industrial Science And Technology Process of treating garbage with simultaneous production of methane
US5711768A (en) 1993-01-19 1998-01-27 Dynecology, Inc. Sewage sludge disposal process and product
US5724805A (en) 1995-08-21 1998-03-10 University Of Massachusetts-Lowell Power plant with carbon dioxide capture and zero pollutant emissions
US5797972A (en) 1993-03-25 1998-08-25 Dynecology, Inc. Sewage sludge disposal process and product
US5816795A (en) 1996-05-24 1998-10-06 Cadence Environmental Energy, Inc. Apparatus and method for providing supplemental fuel to a preheater/precalciner kiln
US5888453A (en) 1997-01-29 1999-03-30 Riverside County Eastern Municipal Water District Continuous flow pasteurization of sewage sludge
US5888307A (en) 1994-03-28 1999-03-30 Cambi As Method and means for hydrolysis of organic materials
US5888256A (en) 1996-09-11 1999-03-30 Morrison; Garrett L. Managed composition of waste-derived fuel
JPH11171628A (en) 1997-12-05 1999-06-29 Kawasaki City Cement composition using burnt ash of sewage sludge, use of the same cement composition and formed product and structure using the same composition
US5975439A (en) 1993-12-23 1999-11-02 Controlled Environmental Systems Corporation Municipal solid waste processing facility and commercial ethanol production process
US6022514A (en) 1998-05-18 2000-02-08 Nkk Corporation Method for recovering phosphorus from organic sludge
US6029588A (en) 1998-04-06 2000-02-29 Minergy Corp. Closed cycle waste combustion
US6036862A (en) 1998-01-20 2000-03-14 Stover; Enos L. Biochemically enchanced thermophilic treatment process
US6063147A (en) 1998-12-17 2000-05-16 Texaco Inc. Gasification of biosludge
US6096283A (en) 1998-04-03 2000-08-01 Regents Of The University Of California Integrated system for the destruction of organics by hydrolysis and oxidation with peroxydisulfate
US6103191A (en) 1997-01-29 2000-08-15 Riverside County Eastern Municipal Water District Continuous flow pasteurization of sewage sludge
US6143176A (en) 1996-05-01 2000-11-07 Ebara Corporation Method of converting organic wastes to valuable resources
US6146133A (en) 1996-06-05 2000-11-14 Heidelberger Zement Ag Process for the recycling of residues for the production of portland cement clinker
US6149694A (en) 1999-06-16 2000-11-21 Northwest Missouri State University Process for using animal waste as fuel
US6176187B1 (en) 1994-03-16 2001-01-23 Cement Industry Environmental Consortium Sludge handling and feeding system
US6197081B1 (en) 1998-03-18 2001-03-06 Erick Schmidt Method for bio-refining waste organic material to produce denatured and sterile nutrient products
US6256902B1 (en) 1998-11-03 2001-07-10 John R. Flaherty Apparatus and method for desiccating and deagglomerating wet, particulate materials
US6365047B1 (en) 1997-06-05 2002-04-02 Applikations-und Technikzentrum für Energieverfahrens-Umwelt-, und Strömungstechnik (ATZ-EVUS) Method and device for treating biogenic residues
WO2002036506A1 (en) 2000-11-04 2002-05-10 Biwater Treatment Limited Method and apparatus for the treatment of sludge
WO2002081379A1 (en) 2001-04-04 2002-10-17 Hanwha Chemical Corporation Process for treating waste water containing a nitrous organic components
US6470812B1 (en) 1997-06-11 2002-10-29 Cemex, S.A. De C.V. Method and apparatus for recovering energy from wastes by combustion in industrial furnaces
US20040025715A1 (en) 2000-08-22 2004-02-12 Torben Bonde Concept for slurry separation and biogas production
US6692544B1 (en) 2000-04-12 2004-02-17 Ecosystems Projects, Llc Municipal waste briquetting system and method of filling land
US6740205B2 (en) 2000-11-30 2004-05-25 The United States Of America As Represented By The Secretary Of The Navy Processing of shipboard wastewater
US20040172878A1 (en) 2001-07-12 2004-09-09 Adam Krylowicz Method and system of generating methane and electrical energy and thermal
US20040192981A1 (en) 2003-03-28 2004-09-30 Appel Brian S. Apparatus and process for converting a mixture of organic materials into hydrocarbons and carbon solids
US6875015B1 (en) 2004-03-27 2005-04-05 John Tiernan Cement producing system incorporating a waste derived fuel suspension burner for a down draft calciner
US20050113611A1 (en) 2003-03-28 2005-05-26 Adams Terry N. Apparatus and process for separation of organic materials from attached insoluble solids, and conversion into useful products
US20050108928A1 (en) 2003-08-22 2005-05-26 Foye Sparks Soil mediums and alternative fuel mediums, methods of their production and uses thereof
US6905600B2 (en) 2001-11-16 2005-06-14 Ch2M Hill, Inc. Method and apparatus for the treatment of particulate biodegradable organic waste
US6913700B2 (en) 1999-05-31 2005-07-05 Cambi As Method of and arrangement for continuous hydrolysis of organic material
US20050145569A1 (en) 2002-05-28 2005-07-07 Ulmert Hans D. Method for treatment of sludge from waterworks and wastewater treatment plants
US6962561B2 (en) 1999-08-25 2005-11-08 Terralog Technologies Usa, Inc. Method for biosolid disposal and methane generation
US6966989B2 (en) 2001-02-14 2005-11-22 Otv S.A. Method and installation for the thermal hydrolysis of sludge
US6973968B2 (en) 2003-07-22 2005-12-13 Precision Combustion, Inc. Method of natural gas production
US20050274068A1 (en) 2004-06-14 2005-12-15 Morton Edward L Bio-solid materials as alternate fuels in cement kiln, riser duct and calciner
US20050274293A1 (en) 2004-06-14 2005-12-15 Lehigh Cement Company Method and apparatus for drying wet bio-solids using excess heat recovered from cement manufacturing process equipment
US20050274066A1 (en) 2004-06-14 2005-12-15 Morton Edward L Method and apparatus for drying wet bio-solids using excess heat from a cement clinker cooler
WO2005121033A1 (en) 2004-06-14 2005-12-22 Fractivator Oy Method and apparatus for manufacture of a useful product from sludge, and its use
US6978725B2 (en) 2004-05-07 2005-12-27 Tecon Engineering Gmbh Process and apparatus for treating biogenic residues, particularly sludges
US20060060526A1 (en) 2003-04-30 2006-03-23 Rupert Binning Method and apparatus for anaerobic digestion of biomasses and generation of biogas
WO2006032282A1 (en) 2004-09-24 2006-03-30 Cambi Bioethanol Aps Method for treating biomass and organic waste with the purpose of generating desired biologically based products
US7101482B2 (en) 2002-08-05 2006-09-05 Otv S.A. Method and facility for treatment of sludge derive from biological water purification facilities
EP1717209A1 (en) 2005-04-26 2006-11-02 Purac Ab Method and system for treating sludge
US7160442B2 (en) 2003-07-28 2007-01-09 Industrial Technology Research Institute Apparatus for reduction of biological wasted sludge
WO2006053020A3 (en) 2004-11-10 2007-02-15 Enertech Environmental Inc Slurry dewatering and conversion of biosolids to a renewable fuel
US20070043246A1 (en) 2002-09-04 2007-02-22 Trevor Bridle Conversion of sludges and carbonaceous materials
US7189074B2 (en) 2000-02-08 2007-03-13 Green Island Environmental Technologies Company Limited Method and process for co-combustion in a waste to-energy facility
US7211229B2 (en) 2001-10-08 2007-05-01 Steris Europe Inc. Suomen Sivuliike Method and apparatus for the sterilization of biological waste
US20070098625A1 (en) 2005-09-28 2007-05-03 Ab-Cwt, Llc Depolymerization process of conversion of organic and non-organic waste materials into useful products
US7252691B2 (en) 2001-03-06 2007-08-07 John Philipson Conversion of municipal solid waste to high fuel value
US7262331B2 (en) 2000-09-04 2007-08-28 Biofuel B.V. Process for the production of liquid fuels from biomass
US7301060B2 (en) 2003-03-28 2007-11-27 Ab-Cwt, Llc Process for conversion of organic, waste, or low-value materials into useful products
US20070289205A1 (en) 2003-08-22 2007-12-20 Foye Sparks Soil mediums and alternative fuel mediums, apparatus and methods of their production and uses thereof
US20080072478A1 (en) 2006-09-22 2008-03-27 Barry Cooper Liquefaction Process
US7434332B2 (en) 2004-06-14 2008-10-14 Lehigh Cement Company Method and apparatus for drying wet bio-solids using excess heat from a cement clinker cooler
WO2009031796A2 (en) 2007-09-03 2009-03-12 Pmc Korea Co., Ltd. A device capable of removal the nitrogen, phosphorus and etc. from sludge
EP1894893B1 (en) 2005-04-27 2014-09-24 Mitsubishi Kakoki Kaisha, Ltd Organic waste disposal facility and method of disposal

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4017420A (en) * 1975-12-22 1977-04-12 Smithkline Corporation Stable oxidase reagent solutions

Patent Citations (169)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3853759A (en) 1968-06-06 1974-12-10 J Titmas Dynamic hydraulic column activation method
US3580193A (en) 1969-09-05 1971-05-25 Dorr Oliver Inc Heat treated waste sludge disposal
US3830636A (en) 1970-02-26 1974-08-20 Black Clawson Fibreclaim Inc Fuel by-products of municipal refuse
US3729042A (en) 1971-02-22 1973-04-24 Pollutant Separation Inc Apparatus for separating pollutants and obtaining separate liquids & solids
US4038152A (en) 1975-04-11 1977-07-26 Wallace-Atkins Oil Corporation Process and apparatus for the destructive distillation of waste material
US4087276A (en) 1975-05-05 1978-05-02 Anic S.P.A. Removal of mercury from sludge by heating and condensing
US4017421A (en) 1975-12-16 1977-04-12 Othmer Donald F Wet combustion process
US4208245A (en) 1977-02-03 1980-06-17 St. Regis Paper Company Pyrolysis of spent pulping liquors
US4128946A (en) 1977-03-08 1978-12-12 Uop Inc. Organic waste drying process
US4126519A (en) 1977-09-12 1978-11-21 Edward Koppelman Apparatus and method for thermal treatment of organic carbonaceous material
US4192653A (en) 1977-12-29 1980-03-11 Gulf Research And Development Company Novel fuel compositions comprising upgraded solid _and/or semi-solid material prepared from coal
US4272322A (en) 1978-04-03 1981-06-09 Masahiro Kobayashi Method for manufacturing charcoals from paper sludge
US4229296A (en) 1978-08-03 1980-10-21 Whirlpool Corporation Wet oxidation system employing phase separating reactor
US4241722A (en) 1978-10-02 1980-12-30 Dickinson Norman L Pollutant-free low temperature combustion process having carbonaceous fuel suspended in alkaline aqueous solution
US4292953A (en) 1978-10-05 1981-10-06 Dickinson Norman L Pollutant-free low temperature slurry combustion process utilizing the super-critical state
US4380960A (en) 1978-10-05 1983-04-26 Dickinson Norman L Pollution-free low temperature slurry combustion process utilizing the super-critical state
US4284015A (en) 1979-03-26 1981-08-18 Dickinson Norman L Pollution-free coal combustion process
US4255129A (en) 1979-07-11 1981-03-10 Thomas N. DePew Apparatus and method for processing organic materials into more useful states
US4377066A (en) 1980-05-27 1983-03-22 Dickinson Norman L Pollution-free pressurized fluidized bed combustion utilizing a high concentration of water vapor
US5114541A (en) 1980-11-14 1992-05-19 Ernst Bayer Process for producing solid, liquid and gaseous fuels from organic starting material
US4593202A (en) 1981-05-06 1986-06-03 Dipac Associates Combination of supercritical wet combustion and compressed air energy storage
US4414813A (en) 1981-06-24 1983-11-15 Knapp Hans J Power generator system
US5630854A (en) 1982-05-20 1997-05-20 Battelle Memorial Institute Method for catalytic destruction of organic materials
US4615711A (en) 1982-11-26 1986-10-07 Mueller Dietrich Sewage sludge fuel briquette
US4477257A (en) 1982-12-13 1984-10-16 K-Fuel/Koppelman Patent Licensing Trust Apparatus and process for thermal treatment of organic carbonaceous materials
US4618735A (en) 1983-09-13 1986-10-21 Canadian Patents And Development Limited Process and apparatus for the conversion of sludges
US4486959A (en) 1983-12-27 1984-12-11 The Halcon Sd Group, Inc. Process for the thermal dewatering of young coals
US4579562A (en) 1984-05-16 1986-04-01 Institute Of Gas Technology Thermochemical beneficiation of low rank coals
US4657681A (en) 1985-04-22 1987-04-14 Hughes William L Method of converting organic material into useful products and disposable waste
US4702745A (en) 1985-05-02 1987-10-27 Kawasaki Jukogyo Kabushiki Kaisha Process for dewatering high moisture, porous organic solid
US4915706A (en) 1985-05-10 1990-04-10 Daley Ralph D Coal-water fuel production
US5050375A (en) 1985-12-26 1991-09-24 Dipac Associates Pressurized wet combustion at increased temperature
US5485728A (en) * 1985-12-26 1996-01-23 Enertech Environmental, Inc. Efficient utilization of chlorine and moisture-containing fuels
US5261225A (en) 1985-12-26 1993-11-16 Dipac Associates Pressurized wet combustion at increased temperature
US5685153A (en) 1985-12-26 1997-11-11 Enertech Environmental, Inc. Efficient utilization of chlorine and/or moisture-containing fuels and wastes
US5000099A (en) 1985-12-26 1991-03-19 Dipac Associates Combination of fuels conversion and pressurized wet combustion
US4714032A (en) 1985-12-26 1987-12-22 Dipac Associates Pollution-free pressurized combustion utilizing a controlled concentration of water vapor
US4898107A (en) 1985-12-26 1990-02-06 Dipac Associates Pressurized wet combustion of wastes in the vapor phase
US4721575A (en) 1986-04-03 1988-01-26 Vertech Treatment Systems, Inc. Method and apparatus for controlled chemical reactions
US4869833A (en) 1986-04-03 1989-09-26 Vertech Treatment Systems, Inc. Method and apparatus for controlled chemical reactions
US4735729A (en) 1986-06-20 1988-04-05 Zimpro Inc. Ash concentration and disposal method
US4909899A (en) 1986-09-22 1990-03-20 A. Ahlstrom Corporation Method of concentrating sludges
US4953478A (en) 1986-10-29 1990-09-04 Enviro-Gro Technologies Odor control for a sludge treatment process
US4989344A (en) 1986-10-29 1991-02-05 Enviro-Gro Technologies Particulate removal for a sludge treatment process
US4829678A (en) 1986-10-29 1989-05-16 Enviro Gro Technologies Sludge treatment process
US5337496A (en) 1986-10-29 1994-08-16 Enviro-Gro Technologies Sludge treatment process
US4956926A (en) 1986-10-29 1990-09-18 Enviro-Gro Technologies Sludge treatment process
US4852269A (en) 1986-10-29 1989-08-01 Enviro-Gro Technologies, Inc. Combined sewage and lime slude treatment process
US4761893A (en) 1986-10-29 1988-08-09 Glorioso John D Sludge treatment process
US4860671A (en) 1986-10-29 1989-08-29 Enviro-Gro Technologies, Inc. Odor control for a sludge treatment process
US4762527A (en) 1986-12-16 1988-08-09 Electric Fuels Corporation Slurry fuel comprised of a heat treated, partially dewatered sludge with a particulate solid fuel and its method of manufacture
US4824561A (en) 1986-12-18 1989-04-25 Basf Corporation Wastewater treatment
US4795568A (en) 1987-06-03 1989-01-03 Chen Philip T Oxidative evaporation process and apparatus
US5132007A (en) 1987-06-08 1992-07-21 Carbon Fuels Corporation Co-generation system for co-producing clean, coal-based fuels and electricity
EP0328574B1 (en) 1987-07-14 1992-01-08 Fhj Process B.V. Process for the conversion and working up of a mixture of organic matter, anorganic matter and water to a nearly dry product, as well as an installation for the execution of the process and application thereof by the conversion of manure slurry
US4765911A (en) 1987-09-14 1988-08-23 North American Metals, Inc. Process for treating municipal wastewater sludge
US5019135A (en) 1987-10-13 1991-05-28 Battelle Memorial Institute Method for the catalytic conversion of lignocellulosic materials
US5009767A (en) 1988-02-02 1991-04-23 Mobil Oil Corporation Recycle of oily refinery wastes
US4983782A (en) 1988-02-27 1991-01-08 Veba Oel Entwicklungs-Gesellschaft Mbh Process for treating wastes and the like by low temperature carbonization and further processing of the low temperature carbonization oil
US5205906A (en) 1988-08-08 1993-04-27 Chemical Waste Management, Inc. Process for the catalytic treatment of wastewater
US4922841A (en) 1988-09-14 1990-05-08 Kent John M Method and apparatus for using hazardous waste to form non-hazardous aggregate
US4875905A (en) 1988-11-14 1989-10-24 Solidiwaste Technology, L.P. Method of preparing a high heating value fuel product
EP0377832B1 (en) 1988-12-13 1993-03-10 Thyssen Still Otto Anlagentechnik GmbH Process for the treatment of biomasses, e.g. sewage sludge, manure, etc.
US5018456A (en) 1989-02-24 1991-05-28 Williams Patent Crusher And Pulverizer Company System for disposing of sludge
US4983296A (en) 1989-08-03 1991-01-08 Texaco Inc. Partial oxidation of sewage sludge
US5292429A (en) 1989-11-29 1994-03-08 Seaview Thermal Systems Process for recovery and treatment of a diverse waste stream
US5087378A (en) 1990-05-31 1992-02-11 Pori, International, Inc. Process for enhancing the dewaterability of waste sludge from microbiological digestion
US5057231A (en) 1990-11-08 1991-10-15 Zimpro Passavant Environmental Systems, Inc. Method for starting up and controlling operating temperature of a wet oxidation process
US5087370A (en) 1990-12-07 1992-02-11 Clean Harbors, Inc. Method and apparatus to detoxify aqueous based hazardous waste
US5221480A (en) 1990-12-07 1993-06-22 Clean Harbors, Inc. Method and apparatus to detoxify aqueous based hazardous waste
US5211724A (en) 1991-04-15 1993-05-18 Texaco, Inc. Partial oxidation of sewage sludge
US5230211A (en) 1991-04-15 1993-07-27 Texaco Inc. Partial oxidation of sewage sludge
US5075015A (en) 1991-05-01 1991-12-24 Zimpro Passavant Environmental Systems, Inc. Method for color removal from thermally conditioned sludge liquors
US5082571A (en) 1991-05-13 1992-01-21 Zimpro Passavant Environmental Systems Inc. Caustic sulfide wet oxidation process
EP0515117B1 (en) 1991-05-20 1995-04-26 Texaco Development Corporation Pumpable aqueous slurries of sewage sludge
US5356540A (en) 1991-05-20 1994-10-18 Texaco Inc. Pumpable aqueous slurries of sewage sludge
US5234468A (en) 1991-06-28 1993-08-10 Texaco Inc. Process for utilizing a pumpable fuel from highly dewatered sewage sludge
US5234469A (en) 1991-06-28 1993-08-10 Texaco Inc. Process for disposing of sewage sludge
US5266085A (en) 1991-09-19 1993-11-30 Texaco Inc. Process for disposing of sewage sludge
US5211723A (en) 1991-09-19 1993-05-18 Texaco Inc. Process for reacting pumpable high solids sewage sludge slurry
US5230810A (en) 1991-09-25 1993-07-27 Zimpro Passavant Environmental Systems, Inc. Corrosion control for wet oxidation systems
US5582793A (en) 1991-10-03 1996-12-10 Antaeus Group, Inc. Process for treating waste material
US5288413A (en) 1991-10-24 1994-02-22 Shell Oil Company Treatment of a waste sludge to produce a non-sticking fuel
US5188739A (en) 1991-12-02 1993-02-23 Texaco Inc. Disposal of sewage sludge
US5188740A (en) 1991-12-02 1993-02-23 Texaco Inc. Process for producing pumpable fuel slurry of sewage sludge and low grade solid carbonaceous fuel
US5183577A (en) 1992-01-06 1993-02-02 Zimpro Passavant Environmental Systems, Inc. Process for treatment of wastewater containing inorganic ammonium salts
US5273556A (en) 1992-03-30 1993-12-28 Texaco Inc. Process for disposing of sewage sludge
US5188741A (en) 1992-04-01 1993-02-23 Texaco Inc. Treatment of sewage sludge
US5234607A (en) 1992-04-22 1993-08-10 Zimpro Passavant Environment Systems Inc. Wet oxidation system startup process
US5349910A (en) 1992-08-06 1994-09-27 F. L. Smidth & Co. A/S Method and apparatus for incinerating waste in a cement kiln plant
US5389259A (en) 1992-08-24 1995-02-14 Zimpro Environmental Inc. Preparation treatment of volatile wastewater components
US5280701A (en) 1992-08-31 1994-01-25 Environmental Energy Systems, Inc. Waste treatment system and method utilizing pressurized fluid
US5339621A (en) 1992-08-31 1994-08-23 Environmental Energy Systems, Inc. Waste treatment system and method utilizing pressurized fluid
US5264009A (en) 1992-09-01 1993-11-23 Texaco Inc. Processing of sewage sludge for use as a fuel
US5292442A (en) * 1992-10-01 1994-03-08 Texaco Inc. Process for disposing of sewage sludge
US5217625A (en) 1992-10-02 1993-06-08 Texaco Inc. Process for disposing of sewage sludge
US5711768A (en) 1993-01-19 1998-01-27 Dynecology, Inc. Sewage sludge disposal process and product
US5240619A (en) 1993-02-11 1993-08-31 Zimpro Passavant Environmental Systems, Inc. Two-stage subcritical-supercritical wet oxidation
US5797972A (en) 1993-03-25 1998-08-25 Dynecology, Inc. Sewage sludge disposal process and product
US5370715A (en) 1993-04-27 1994-12-06 Kortzeborn; Robert N. Waste destructor and method of converting wastes to fluid fuel
US5389264A (en) 1993-07-12 1995-02-14 Zimpro Environmental Inc. Hydraulic energy dissipator for wet oxidation process
US5500044A (en) 1993-10-15 1996-03-19 Greengrove Corporation Process for forming aggregate; and product
US5975439A (en) 1993-12-23 1999-11-02 Controlled Environmental Systems Corporation Municipal solid waste processing facility and commercial ethanol production process
US5586510A (en) 1994-03-16 1996-12-24 Cement Industry Environment Consortium Method and system for controlling pollutant emissions in combustion operations
US6176187B1 (en) 1994-03-16 2001-01-23 Cement Industry Environmental Consortium Sludge handling and feeding system
US5888307A (en) 1994-03-28 1999-03-30 Cambi As Method and means for hydrolysis of organic materials
US5707417A (en) 1994-09-30 1998-01-13 Director-General Of Agency Of Industrial Science And Technology Process of treating garbage with simultaneous production of methane
US5724805A (en) 1995-08-21 1998-03-10 University Of Massachusetts-Lowell Power plant with carbon dioxide capture and zero pollutant emissions
US5641413A (en) 1995-10-27 1997-06-24 Zimpro Environmental, Inc. Removal of nitrogen from wastewaters
US6143176A (en) 1996-05-01 2000-11-07 Ebara Corporation Method of converting organic wastes to valuable resources
US5816795A (en) 1996-05-24 1998-10-06 Cadence Environmental Energy, Inc. Apparatus and method for providing supplemental fuel to a preheater/precalciner kiln
US6146133A (en) 1996-06-05 2000-11-14 Heidelberger Zement Ag Process for the recycling of residues for the production of portland cement clinker
US5888256A (en) 1996-09-11 1999-03-30 Morrison; Garrett L. Managed composition of waste-derived fuel
US5888453A (en) 1997-01-29 1999-03-30 Riverside County Eastern Municipal Water District Continuous flow pasteurization of sewage sludge
US6103191A (en) 1997-01-29 2000-08-15 Riverside County Eastern Municipal Water District Continuous flow pasteurization of sewage sludge
US6365047B1 (en) 1997-06-05 2002-04-02 Applikations-und Technikzentrum für Energieverfahrens-Umwelt-, und Strömungstechnik (ATZ-EVUS) Method and device for treating biogenic residues
US6470812B1 (en) 1997-06-11 2002-10-29 Cemex, S.A. De C.V. Method and apparatus for recovering energy from wastes by combustion in industrial furnaces
JPH11171628A (en) 1997-12-05 1999-06-29 Kawasaki City Cement composition using burnt ash of sewage sludge, use of the same cement composition and formed product and structure using the same composition
US6036862A (en) 1998-01-20 2000-03-14 Stover; Enos L. Biochemically enchanced thermophilic treatment process
US6197081B1 (en) 1998-03-18 2001-03-06 Erick Schmidt Method for bio-refining waste organic material to produce denatured and sterile nutrient products
US6096283A (en) 1998-04-03 2000-08-01 Regents Of The University Of California Integrated system for the destruction of organics by hydrolysis and oxidation with peroxydisulfate
US6029588A (en) 1998-04-06 2000-02-29 Minergy Corp. Closed cycle waste combustion
US6022514A (en) 1998-05-18 2000-02-08 Nkk Corporation Method for recovering phosphorus from organic sludge
US6256902B1 (en) 1998-11-03 2001-07-10 John R. Flaherty Apparatus and method for desiccating and deagglomerating wet, particulate materials
US6436157B1 (en) 1998-12-17 2002-08-20 Texaco Inc. Gasification of biosludge
US6063147A (en) 1998-12-17 2000-05-16 Texaco Inc. Gasification of biosludge
US6913700B2 (en) 1999-05-31 2005-07-05 Cambi As Method of and arrangement for continuous hydrolysis of organic material
US6149694A (en) 1999-06-16 2000-11-21 Northwest Missouri State University Process for using animal waste as fuel
US6962561B2 (en) 1999-08-25 2005-11-08 Terralog Technologies Usa, Inc. Method for biosolid disposal and methane generation
US7189074B2 (en) 2000-02-08 2007-03-13 Green Island Environmental Technologies Company Limited Method and process for co-combustion in a waste to-energy facility
US6692544B1 (en) 2000-04-12 2004-02-17 Ecosystems Projects, Llc Municipal waste briquetting system and method of filling land
US20040025715A1 (en) 2000-08-22 2004-02-12 Torben Bonde Concept for slurry separation and biogas production
US7262331B2 (en) 2000-09-04 2007-08-28 Biofuel B.V. Process for the production of liquid fuels from biomass
WO2002036506A1 (en) 2000-11-04 2002-05-10 Biwater Treatment Limited Method and apparatus for the treatment of sludge
US6740205B2 (en) 2000-11-30 2004-05-25 The United States Of America As Represented By The Secretary Of The Navy Processing of shipboard wastewater
US6966989B2 (en) 2001-02-14 2005-11-22 Otv S.A. Method and installation for the thermal hydrolysis of sludge
US7252691B2 (en) 2001-03-06 2007-08-07 John Philipson Conversion of municipal solid waste to high fuel value
WO2002081379A1 (en) 2001-04-04 2002-10-17 Hanwha Chemical Corporation Process for treating waste water containing a nitrous organic components
US20040172878A1 (en) 2001-07-12 2004-09-09 Adam Krylowicz Method and system of generating methane and electrical energy and thermal
US7211229B2 (en) 2001-10-08 2007-05-01 Steris Europe Inc. Suomen Sivuliike Method and apparatus for the sterilization of biological waste
US6905600B2 (en) 2001-11-16 2005-06-14 Ch2M Hill, Inc. Method and apparatus for the treatment of particulate biodegradable organic waste
US7311834B2 (en) 2001-11-16 2007-12-25 Ch2M Hill, Inc. Apparatus for the treatment of particulate biodegradable organic waste
US20050145569A1 (en) 2002-05-28 2005-07-07 Ulmert Hans D. Method for treatment of sludge from waterworks and wastewater treatment plants
US7101482B2 (en) 2002-08-05 2006-09-05 Otv S.A. Method and facility for treatment of sludge derive from biological water purification facilities
US20070043246A1 (en) 2002-09-04 2007-02-22 Trevor Bridle Conversion of sludges and carbonaceous materials
US20040192981A1 (en) 2003-03-28 2004-09-30 Appel Brian S. Apparatus and process for converting a mixture of organic materials into hydrocarbons and carbon solids
US7301060B2 (en) 2003-03-28 2007-11-27 Ab-Cwt, Llc Process for conversion of organic, waste, or low-value materials into useful products
US7179379B2 (en) 2003-03-28 2007-02-20 Ab-Cwt, Llc Apparatus for separating particulates from a suspension, and uses thereof
US20040192980A1 (en) * 2003-03-28 2004-09-30 Appel Brian S. Process for conversion of organic, waste, or low-value materials into useful products
US20050113611A1 (en) 2003-03-28 2005-05-26 Adams Terry N. Apparatus and process for separation of organic materials from attached insoluble solids, and conversion into useful products
US20060060526A1 (en) 2003-04-30 2006-03-23 Rupert Binning Method and apparatus for anaerobic digestion of biomasses and generation of biogas
US6973968B2 (en) 2003-07-22 2005-12-13 Precision Combustion, Inc. Method of natural gas production
US7160442B2 (en) 2003-07-28 2007-01-09 Industrial Technology Research Institute Apparatus for reduction of biological wasted sludge
US20070289205A1 (en) 2003-08-22 2007-12-20 Foye Sparks Soil mediums and alternative fuel mediums, apparatus and methods of their production and uses thereof
US20050108928A1 (en) 2003-08-22 2005-05-26 Foye Sparks Soil mediums and alternative fuel mediums, methods of their production and uses thereof
US6875015B1 (en) 2004-03-27 2005-04-05 John Tiernan Cement producing system incorporating a waste derived fuel suspension burner for a down draft calciner
US6978725B2 (en) 2004-05-07 2005-12-27 Tecon Engineering Gmbh Process and apparatus for treating biogenic residues, particularly sludges
US7434332B2 (en) 2004-06-14 2008-10-14 Lehigh Cement Company Method and apparatus for drying wet bio-solids using excess heat from a cement clinker cooler
WO2005121033A1 (en) 2004-06-14 2005-12-22 Fractivator Oy Method and apparatus for manufacture of a useful product from sludge, and its use
US20050274066A1 (en) 2004-06-14 2005-12-15 Morton Edward L Method and apparatus for drying wet bio-solids using excess heat from a cement clinker cooler
US20050274293A1 (en) 2004-06-14 2005-12-15 Lehigh Cement Company Method and apparatus for drying wet bio-solids using excess heat recovered from cement manufacturing process equipment
US20050274068A1 (en) 2004-06-14 2005-12-15 Morton Edward L Bio-solid materials as alternate fuels in cement kiln, riser duct and calciner
WO2006032282A1 (en) 2004-09-24 2006-03-30 Cambi Bioethanol Aps Method for treating biomass and organic waste with the purpose of generating desired biologically based products
WO2006053020A3 (en) 2004-11-10 2007-02-15 Enertech Environmental Inc Slurry dewatering and conversion of biosolids to a renewable fuel
EP1717209A1 (en) 2005-04-26 2006-11-02 Purac Ab Method and system for treating sludge
EP1894893B1 (en) 2005-04-27 2014-09-24 Mitsubishi Kakoki Kaisha, Ltd Organic waste disposal facility and method of disposal
US20070098625A1 (en) 2005-09-28 2007-05-03 Ab-Cwt, Llc Depolymerization process of conversion of organic and non-organic waste materials into useful products
US20080072478A1 (en) 2006-09-22 2008-03-27 Barry Cooper Liquefaction Process
WO2009031796A2 (en) 2007-09-03 2009-03-12 Pmc Korea Co., Ltd. A device capable of removal the nitrogen, phosphorus and etc. from sludge

Non-Patent Citations (10)

* Cited by examiner, † Cited by third party
Title
C.F. Forster, "Preliminary Studies on the Relationship Between Sewage Sludge Viscosities and the Nature of the Surfaces of the Component Particles", Biotechnology Letters, 3(12), 707-712, 1981.
CH2MHill and Itron, Task 2.2.1 Final Report prepared for the California Energy Commission, "Commonwealth Energy Biogas/PV Mini-Grid Renewal Resources Program, Making Renewables Part of an Affordable and Diverse Electric System in California, Contract No. 500-00-036, Process Selection Report for Wastewater Treatment Plants, Project No. 2.2 Enhanced Energy Recovery Through Optimization of Anaerobic Digestion and Microturbines", Aug. 2003.
International Search Report and Written Opinion dated Sep. 6, 2010 in International Application No. PCT/US2010/030197.
Kelly, Harlan G., "Emergy Processes in Biosolids Treatment, 2005", Journal of Environmental Engineering and Science, May 2006.
Neyens, E. et al., "A review of thermal sludge pre-treatment processes to improve dewaterability", Journal of Hazardous Materials, 2003, pp. 51-67.
Partial International Search Report for International Application No. PCT/US2010/030197, Jun. 30, 2010 (6 pages).
Presentation-EnerTech Environmental, Inc., Introduction of the Rialto Regional Biosolids Project, Oct. 23, 2003 (10 pages).
W.L. McCabe et al., "Unit Operations of Chemical Engineering", 5th Edition, McGraw-Hill, pp. 189-191, 1993.
Walley, Paul, "Optimising Thermal Hydrolysis for Reliable High Digester Solids Loading and Performance", 12th European Biosolids and Organic Resources Conference, 2007.
Weemaes, Marjoleine P.J., et al., "Evaluation of Current Wet Sludge Disintegration Techniques", Centre for Environmental Sanitation, University Ghent, Ghent, Belgium, Jun. 12, 1998.

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