Search Images Maps Play YouTube News Gmail Drive More »
Sign in
Screen reader users: click this link for accessible mode. Accessible mode has the same essential features but works better with your reader.


  1. Advanced Patent Search
Publication numberUS3247678 A
Publication typeGrant
Publication date26 Apr 1966
Filing date2 Oct 1963
Priority date2 Oct 1963
Publication numberUS 3247678 A, US 3247678A, US-A-3247678, US3247678 A, US3247678A
InventorsJohn W Mohlman
Original AssigneeJohn W Mohlman
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Air conditioning with ice-brine slurry
US 3247678 A
Abstract  available in
Previous page
Next page
Claims  available in
Description  (OCR text may contain errors)

A ril 26, 1966 J. w. MOHLMAN 3, 4


JOHN W. MOHLMAN ATTORNEY United States Patent M 3,247,678 AIR CONDITIONING WITH ICE-BRINE SLURRY John W. Mohlman, 4600 Van Alden St., Tarzana, Calif. Filed Oct. 2, 1963, Ser. No. 313,208 5 Claims. (Cl. 62-199) This invention relates generally to air conditioning by refrigeration and more particularly to refrigeration with an ice brine slurry.

Systems have been proposed heretofore for supplying cold water from a single refrigeration station as a common source to numerous ofl'lce, apartment and residential buildings for air conditioning purposes. The advantages of a common source for refrigeration, resulting in increased efliciency of operation, are evident; however, inasmuch as the heat capacity of Water as a refrigerant is relatively low, it is necessary to circulate relatively large volumes of water in a system in order to derive a required minimal of refrigeration. Large pipes and heavy duty equipment are needed.

' It is a general object of this invention to provide a system and method for air conditioning purposes utilizing an ice-brine slurry from a single refrigeration station for supplying numerous users with refrigeration, it being contemplated that such users (or customers) will pay for their metered consumption of refrigeration; By this invention the air to be cooled is passed in heat exchange relationship with the ice-brine slurry whereby the latent heat for melting of the ice is removed from the air. Thus, inasmuch as the heat of melting or heat of fusion for ice is about 80 times greater than the heat capacity of an equal weight of water, 'a relatively small Volume of icebrine slurry will provide the same amount of refrigeration as a much larger volume of cold water, with the result that smaller pipes and processing equipment are needed to convey the slurry from the refrigeration station to the air conditioning units.

The use of brine instead of Water makes it practicable to control the temperature at which ice crystals are formed for the slurry, thereby to effect control of the ice content in the slurry, as is explained more fully hereinafter.

\Further objects and advantages Will appear in the following part of this specification wherein the details of construction and mode of operation of a preferred embodiment of the invention are described with reference to the accompanying drawing, the single figure of which is a schematic representation of such embodiment.

In the drawing, the spaces -10, I l and '12, outlined by broken lines, represent a plurality of apartments or offices in a building to be furnished with metered refrigeration, or consider-ing this invention in a broader aspect, the spaces may be viewed as representing a plurality of buildings located in a section or district of suit-able area for distribution of refrigeration from a common refrigeration station. Each such apartment, office, or building has an air conditioning unit 14 each of which is represented in the drawing as comprising a coiled pipe :15 adjacent a fan 16 driven by a motor 417, the flow of icebrine slurry into the coiled pipe being controlled by a valve 18. The fan 17 circulates air within the space over and through the coil whereby the air is cooled with concomitant Warming of the slurry 'to an extent such that the ice in the slurry melts.

Each air conditioning unit is connected to a manifold conduit or flow line 20 leading from an elevated head tank 22. The head tank receives ice-brine slurry through a flow line 24- which includes a main pump as. An auxiliary pump 27 is connected at its outlet end to the flow line 24 by a branch line 28. The pumps receive icebrine slurry from a flow line 30 having inlet connections 31 and 32 for the pumps 26 and 627 respectively. The

3,247,678 Patented Apr. 26, 1966 auxiliary pump Q17 is designed for continuous operation whereas the larger pump 26 operates intermittently to meet the demand for refrigeration when the air conditioning units are in use. For controlling operation of the pump 26, the head tank 22 is equipped with a liquid level controller 34 which is electricallyconnected by a Wire 35 to the pump 26 such that when the ice-brine slurry in the head tank reaches a predetermined lower level, the pump '26 will be energized, and when the slurry reaches a predetermined upper level the pump 26 will be de-energized.

\Flow line 30 constitutes the product output line of a suitable refrigeration system for producing an ice brine slurry. For the illustrated embodiment the refrigeration system, designated generally by reference numeral 38, is of the type in which partial crystallization of water through freezing is effected by direct contact of the feed liquid with an immiscible and vol-atilizable refrigerant, as is described in US. Patent 3,098,733 for conversion of sea water to potable Water. The illustrated refrigeration system 38 comprises a freezer 40 containing brine 41. Fractional crystallization of the water in the brine occurs from the passing of an immisicible and volatilizable refrigerant, e.g., butane, in liquid phase in direct contact with the brine in the freezer, whereby the liquid refrigerant volatilizes in the freezer, deriving its heat of vaporization from the brine and thereby cooling the brine to a temperature at which ice crystals form in the brine.

A conduit 43 from the top of the freezer 40 and containing a compressor 45 conveys the refrigerant vapor from the freezer to a condenser 47 in which the compressed refrigerant vapors are converted to liquid phase. Reference numerals 48 and 49 design-ate an inlet and an outlet respectively for flow cooling of Water through the condenser. From the condenser the liquid refrigerant passes by line 51 to a reservoir 52. A pump 54 in flow line 56 pumps the liquid refrigerant from the reservoir to a sparger 58 in the freezer for direct contact with the brine in the freezer, thus completing the cycle of flow for the refrigerant.

-For controlling the operation of the compressor 45 and the liquid-refrigerant pump 54, there is an instrument 60 electrically connected by wire 61 to a temperature responsive element 62 positioned in the freezer proximate the slurry outlet 63 of the freezer. Instrument 60 is electrically connected by Wires 64 and 65 to the compressor 45 and the pump 54 respectively for on-otf control of the compressor and of the pump in response to reaching of predetermined temperature limits of the brine in the freezer as will appear more fully hereinafter.

The freezer 40 is replenished with feed brine through a return pipe or line or leading from the downstream end of the manifold pipe 20 to the brine inlet 69 of the freezer. Also connected to the brine return pipe 67 is another manifold flow line '70 to which the outlet end of each coiled pipe 15 of the air conditioning unit 14 is connected.

For efficient operation of a system of this invention, the system should be regulated to limit the ice content or the slurry which is passed from the refrigeration station 38 to the air conditioning units 14. Were the ice content of the slurry to reacha value greater than about 20 percent by weight, clogging of the equipment would be apt to occur. A slurry of an ice content less than about 10 percent would provide too thin a slurry for economical purposes. Then, too, the size of the ice crystals should be maintained below about 5 mm. in longest dimension to prevent clogging and to deter too rapid separation by floating of the ice crystals upon the brine liquor.

The factors of ice content and crystal size are regulated by controlled operation of the refrigeration station 38. When a brine of sodium chloride is used in the system of this invention, the salt content in the feed brine, is. brine entering the freezer at inlet 69, should preferably be from about 2 to about percent by weight. With sea water, for example, which has a salt content of about 3 /2 percent, ice crystals begin to form when the temperature of the brine reaches about 28.5 F., and an ice-brine slurry of about 20 percent ice will form by reducing the temperature of the brine by about two degrees lower than the initial freezing point. With a brine feed of about 2 percent salt content, reduction in temperature of about 1 F. from its initial freezing temperature of about 30 F. will produce a slurry of about 20 percent ice content. Thus it is that a higher salt content in the feed brine provides a greater range in freezing temperature for the production of a slurry of a given ice content, enabling more precise control of the ice content with the temperature controller 60.

The size of the ice crystals formed in the freezer is dependent upon the temperature of the volatilizing refrigerant and upon the residence time of the crystals in the freezer. The compressor 45 reduces the pressure in the freezer. When warm butane (about 85 to 90 F.) enters the freezer, it flashes to vapor because of the reduced pressure in the freezer and thereby substantially cools the liquid butane. For production of fine crystals the compressor should be powered to provide suificient vacuum in the freezer for reduction in the temperature of the flashing butane to from about 2 to 3 F. below the freezing temperature of the brine. The compressor 45 heats the butane vapor to a temperature in the neighborhood of about 100 F. Assuming the temperature of the cooling water for the condenser 47 to be from about 65 to 70 F., the temperature of the condensed butane from the condenser will be from about 85 to about 90 F.

The auxiliary pump 27 maintains continuous fiow of slurry through the system thereby providing for agitation of the slurry in the head tank 22 and for movement of brine through the freezer.

It will be understood that it is intended to cover all changes and modifications of the example of the invention herein chosen for the purposes of this disclosure, which do not constitute departures from the spirit and scope of the invention.

Having described the invention, what is claimed is:

1. A system for refrigeration of air in a space comprising freezer means admitting feed brine and exhausting an ice brine slurry, means to form ice crystals in the brine in the freezer, an elevated head tank, a first conduit and first pump for passing said slurry from the freezer to said head tank, a conduit in said space connected to said head tank for receiving said slurry from said tank, means for moving said air in heat exchange with said slurry in said space thereby to melt the ice in said slurry and to refrigerate said air, and means for returning the brine from, sa d eat c a g me to aid freezer.

2. A system forrefrigeration of air in space comprising a freezer means admitting feed brine and exhausting an ice-brine slurry, means for passing an immiscible and volatilizable refrigerant through the contents of the freezer thereby to form ice crystals in the brine in the freezer, an elevated head tank, a first conduit and first pump for passing said slurry from the freezer to said head tank, a conduit in said space connected to said head tank for receiving said slurry from said tank, means for moving said air in heat exchange with said slurry in said space thereby to melt the ice in said slurry and to refrigerate said air, and means for returning the brine from said heat exchange means to said freezer.

3. A system according to claim 2 and including an auxiliary pump and branch line connected to the outlet of said freezer and to said first conduit at a point downstream of said first pump for continuous flow from the freezer to said head tank thence to said space and return to said freezer.

4. A system according to claim 3 and including a liquid level controller on said head tank and operatively connected to said first pump for on-off control of said first pump in response to changes in the level of slurry between predetermined levels in the head tank.

5. A system for selective refrigeration of air in a plurality of spaces comprising a refrigeration station for converting a feed brine to an ice-brine slurry of from about 10 to 20 weight percent of ice crystals in residual brine, an elevated head tank, a first conduit and pump for passing said slurry from said station to said head tank, heat exchange air conditioning units in said spaces respectively, means for flowing said slurry from said head tank to said units, each of said air conditioning units comprising a fan and a conduit for passing air in heat exchange with said slurry thereby to melt the ice crystals in said slurry to reform said feed brine and to refrigerate said air, and means for returning said feed brine from said units to said station.

References Cited by the Examiner UNITED STATES PATENTS 310,025 12/1884 Brewer 62121 485,217 11/1892 Parshall 62114 X 1,185,597 5/1916 Eddy 62-442 X 2,101,953 12/1937 Oman 62--58 2,191,623 2/1940 Philipp 62-393 X 2,251,706 8/1941 Lowry 62331 2,349,671 5/1944 Newton 62333 X 2,751,762 6/1956 Colton 62-114 X 2,927,101 3/1960 Tegge et al 62--389 2,975,609 3/1961 Allander et al 62 4 4 2 x MEYER PERLIN, Primary Examiner.


LLOYD L, KING, Assistant Examiner,

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US310025 *7 Feb 188330 Dec 1884 Method of and apparatus for refrigerating liquids
US485217 *17 Nov 18911 Nov 1892 Refrigerating apparatus
US1185597 *17 Jun 191030 May 1916Charles E ShepardMethod of refrigeration.
US2101953 *12 Sep 193614 Dec 1937Oman ErikMethod and apparatus for producing cold
US2191623 *8 Jun 193727 Feb 1940Nash Kelvinator CorpRefrigerating apparatus
US2251706 *24 May 19395 Aug 1941Chrysler CorpApparatus for decorating the interior and improving the atmosphere of enclosures
US2349671 *23 Dec 194023 May 1944Honeywell Regulator CoControl of refrigeration
US2751762 *8 Aug 195226 Jun 1956Proctor Drying And Freezing CoMethod of freezing materials
US2927101 *5 Oct 19541 Mar 1960Exxon Research Engineering CoLiquid-liquid heat exchange in low temperature polymerization
US2975609 *30 Jul 195621 Mar 1961Svenska Flaektfabriken AbAir conditioning
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3340700 *12 Jan 196612 Sep 1967Harold L BoeseLiquid gas refrigeration system
US3365904 *28 Nov 196630 Jan 1968Ritter Pfaudler CorpChilled water accumulator with vacuum deaeration
US3385073 *6 Oct 196628 May 1968Cryo Therm IncRefrigeration system for shipping perishable commodities
US3440831 *6 Feb 196729 Apr 1969Stanley S ThompsonQuick freeze process
US3869870 *2 Jul 197311 Mar 1975Borg WarnerRefrigeration system utilizing ice slurries
US3906742 *4 Feb 197423 Sep 1975Borg WarnerAir conditioning system utilizing ice slurries
US4124998 *24 Jan 197714 Nov 1978Canada Square Management Ltd.Air conditioning systems for buildings
US4302944 *15 Jul 19801 Dec 1981Westinghouse Electric Corp.Thermal storage method and apparatus
US4480445 *21 Jan 19836 Nov 1984Vladimir GoldsteinThermal storage heat exchanger systems of heat pumps
US4540501 *12 Sep 198410 Sep 1985The United States Of America As Represented By The United States Department Of EnergyGas hydrate cool storage system
US4554797 *1 Oct 198426 Nov 1985Vladimir GoldsteinThermal storage heat exchanger systems of heat pumps
US4593538 *21 Sep 198410 Jun 1986Ben-Gurion University Of The Negev Research And Development AuthorityRefrigeration cycle operatable by low thermal potential energy sources
US4750333 *3 Oct 198314 Jun 1988Chicago Bridge & Iron CompanyIntegrated mine cooling and water conditioning system
US4757690 *19 Nov 198719 Jul 1988Carrier CorporationWater freezing enhancement for thermal storage brine tube
US4796441 *28 Sep 198710 Jan 1989Sunwell Engineering Company LimitedIce making machine
US4838039 *21 Apr 198813 Jun 1989Cbi Research CorporationDirect contact evaporator/freezer
US4843826 *9 Oct 19874 Jul 1989Cryodynamics, Inc.Vehicle air conditioner
US4864831 *11 Jul 198812 Sep 1989Kajima CorporationIce storage refrigerating apparatus of direct contact type
US4914921 *16 Aug 198810 Apr 1990Cbi Research CorporationRefrigeration method and apparatus using aqueous liquid sealed compressor
US4984435 *7 Jul 198915 Jan 1991Dairei Co. Ltd.Brine refrigerating apparatus
US5099657 *9 Jan 199131 Mar 1992Huang Chia TsaiStructure of cooling tank for water cooler
US5123262 *13 Nov 199023 Jun 1992Thermique Generale Et VinicoleCold transfer method and device
US5139549 *5 Apr 199118 Aug 1992Chicago Bridge & Iron Technical Services CompanyApparatus and method for cooling using aqueous ice slurry
US5191772 *13 Feb 19929 Mar 1993Pacific Rockies, Inc.Auger-type ice-making apparatus
US5218828 *23 Oct 199215 Jun 1993Kajima CorporationMethod and apparatus for storing heat in ice by using refrigerant jet
US5307641 *6 Jan 19933 May 1994Chicago Bridge & Iron Technical Services CompanyMethod and apparatus for producing ice by direct contact of a non-hydrate producing refrigerant with water
US5327736 *5 May 199312 Jul 1994Kajima CorporationMethod and apparatus for storing heat in ice by using refrigerant jet
US5524442 *27 Jun 199411 Jun 1996Praxair Technology, Inc.Cooling system employing a primary, high pressure closed refrigeration loop and a secondary refrigeration loop
US5832738 *12 Feb 199710 Nov 1998Daewoo Electronics Co., Ltd.Refrigerator having a plurality of evaporators
US6205795 *21 May 199927 Mar 2001Thomas J. BackmanSeries secondary cooling system
US86777683 Dec 201025 Mar 2014Innovel 2000 Inc.System and method for purifying a first liquid content and simultaneously heating a second liquid content
US20050066679 *30 Sep 200331 Mar 2005Boyer Jack ClydeDistributed operator cooling system
US20100212336 *17 Sep 200826 Aug 2010Scottish & Newcastle LimitedControl system
US20150083374 *13 Mar 201426 Mar 2015J. Peter Clark, IIIClosed Loop Ice Slurry Refrigeration System
USD745839 *27 Oct 201422 Dec 2015James E. WhittakerMirror extension mounting bracket
EP0107755A1 *29 Jul 19839 May 1984Gebrüder Sulzer AktiengesellschaftDirect evaporation energy accumulator
EP0427648A1 *9 Nov 199015 May 1991Thermique Generale Et VinicoleMethod and device for the transfer of cold
WO1987004510A1 *16 Jan 198730 Jul 1987Coldeco S.A.Method for generating and using cold, and device for implementing such method
WO2000029792A2 *16 Nov 199925 May 2000James G BoykoDirect-contact ice-generation device
WO2000029792A3 *16 Nov 19998 Sep 2000James G BoykoDirect-contact ice-generation device
U.S. Classification62/199, 62/373, 62/185, 62/331, 62/118, 62/540, 62/215, 62/434, 62/442, 62/50.6, 62/50.7, 62/54.1, 62/534
International ClassificationF25D17/02, F24F5/00, F25D17/00
Cooperative ClassificationY02E60/147, F24F5/0017, F25D17/02
European ClassificationF25D17/02, F24F5/00C5