US20090211223A1

US20090211223A1 - High efficient heat engine process using either water or liquefied gases for its working fluid at lower temperatures

Info

Publication number: US20090211223A1
Application number: US12/035,851
Authority: US
Inventors: James Shihfu Shiao
Original assignee: Daw Shien Scientific Research and Development Inc
Current assignee: Daw Shien Scientific Research and Development Inc
Priority date: 2008-02-22
Filing date: 2008-02-22
Publication date: 2009-08-27

Abstract

The high efficient heat engine process can use either water or liquefied gases for its working fluid to extract thermal energy from the ambient or non-ambient heat sources to increase its heat transfer rate and its power generation efficiency. The slower-speed two-phase turbine has a high ratio gear reducer to increase a generator's speed and produce power at about 50% efficiency. A high ratio gear reducer is used to increase its generator's speed and meet its power generation requirements (3,600 RPM). The two-phase separator and compressor/pump substitute the cooling condenser's position and compress the waste streams directly back to the boiler and allow the process to run at temperatures lower than room temperature, with no need for a conventional cooling condenser. Owing to these two-phase separator/compressor/pump processes, this new heat engine process will not discharge thermal pollution and/or radioactive/hazardous wastes into the heat sink and global environment.

Description

I. FIELD OF THE INVENTION

The present invention relates generally to generating power at lower temperatures by using liquefied gases as a working fluid via a heat engine process, and more particularly to a method of using slower-speed, balanced turbines attached to a high-ratio gear reducer to increase the generator's speed and meet its power generation requirements.

II. BACKGROUND OF THE INVENTION

In recent years, the conventional steam engine, air conditioner, and refrigerator have demanded higher efficiency, which need higher power producing benefit requirements and more advanced technology.
The conventional steam engine only has about 30% efficiency, and the conventional air conditioner and refrigerator require outside power to run their compressors.
The conventional air conditioner and refrigerator are considered heat pumps because they have similar four process elements of a heat engine, but they are called by different names. The conventional heat pump runs its process in a counter clock-wise direction through those four elements (freezer-compressor-cooling condenser-expansion valve), which is the reverse direction of the conventional heat engine process (boiler-turbines-cooling condenser-pump). Therefore, the heat engine process can generate power, and the heat pump process can only be run by outside power through its compressor.
Typically, a conventional heat pump would not operate as a conventional heat engine by reversing its process direction and generate power, because there was a heat exchanger called the cooling condenser, which was set at the waste stream ready to take heat out of the working fluid. This cooling condenser needed another colder cooling fluid pumped into the cooling condenser doing the heat exchange. That cooling fluid was typically cold water because it was cheaper and easier to get, and its temperature was around room temperature for the heat engine process and also for the heat pump process.
If a heat pump operated similar to the heat engine process by only reversing its operation direction, then its cooling fluid's temperature would be even much lower than the room temperature and the waste stream temperature. If the conventional heat engine refrigerant's and cooling fluid's temperatures run much lower than the room temperature, this lower temperature cooling fluid will take more outside power than the conventional heat engine can produce.
Therefore, since a cooling condenser is set to extract heat from the working fluid, there will be no net benefit of just reversing the operating direction from the conventional heat pump into a conventional heat engine process.
In the present process, these slower-speed turbines can take more pressure difference and more vapor speed difference. It is needed to design with more strength, more stable rotating at a slower-speed, and less ball-bearing friction wear. The slower-speed turbines are connected to a high ratio gear reducer to increase the generator's rotating speed and meet its power generation requirements.
This slow-speed, with strengthened and stable running, two-phase turbines with attached high ratio gear reducer can use the force of high speed condensed phase to generate more useful power and minimize the disadvantages of running turbines in the condensed phase flow (minimize droplet erosions and thermal strength fatigue).
Another advantage of the stronger and slow-speed turbines with a high ratio gear reducer is to make the turbines run through the condensed phase fluid with the high speed condensed phase generating more useful power, more efficiently, less instability, and easier to be built and maintained.
Then, the conventional heat engine with condenser process needs to be alternated, and the new two-phase separator/compressor/pump have been proposed to substitute the conventional cooling condenser's function for putting power back into the working fluid stream of boiler.
The new heat engine process (using the liquefied oxygen or nitrogen as its working fluid) will have a higher efficiency of close to 50% efficiency, and can produce power under temperatures lower than the ambient temperature. This powerful heat engine process may use liquefied gases (oxygen or nitrogen) for its working fluid transferring energy and extracting work from ambient energy for our new air conditioner and new refrigerator without damaging the environment (with no chemical refrigerants leaking, no hot cooling water discharge, no thermal pollution, and no radioactive/hazardous waste discharge of the conventional nuclear power plants' cooling towers).
The solar panel cell generates practical power from absorbing heat at a single operating temperature, so it is possible to construct a perpetual device using solar panel power, whose only effect is to absorb the ambient heat and generate power. And also by using this power, it can reject heat from low temperature to high temperature. The solar panel cell is one of many devices, whose functions are perpetual under ambient energy.
Another example is the Earth's tides. The tides action is perpetual from absorbing energy at a single ambient operating temperature to generate work, which is from the moon's gravitational energy.
A wind power device is another example of a perpetual device, which absorbs energy at a single ambient operating temperature and generates work from the sun. The solar energy devices must be perpetual by absorbing energy from single ambient operating temperature to generate power for so long. So does this invention.
The sun, earth, moon are always perpetual by absorbing energy from single ambient operating temperature to generate power. Therefore, we may make a second law statement of Thermodynamics according to these universe facts: There are some self-perpetual objects and devices, whose functions are to absorb energy from single ambient operating temperature, use it, and generate power for as long as solar panels, wind mills, and tidal power devices work.
The New DawShien Modified Statement (present invention): It can construct a perpetual and cyclic process, whose effect is to generate power by absorbing the ambient temperature of solar power (without solar power our temperature would be close to be 0 K) and pumping the working fluid back to the boiler without discarding heat into the heat sink.
The present invention can also construct a perpetual and cyclic process by using liquefied oxygen or nitrogen as its heat engine's working fluid, whose effect is to generate power by absorbing the ambient temperature of the solar power (transfer energy and extract work from solar energy and also cool down the surrounding temperature lower than the room temperature for our new air conditioner and new refrigerator system), and by compressing the waste streams directly back to the boiler (a place to restore heat) without discarding waste heat at heat sink.

III. SUMMARY OF THE INVENTION

The present invention utilizes a two-phase separator/compressor/pump (compress gases and pump the liquid in two stages, separately), from which these condensed two-phase streams can be pushed back into a boiler, immediately after the condensed phases come out from the two-phase separator. At the same time, the two-phase compressor/pump substitutes the cooling condenser position while using pushing power to complete this heat engine cycle (which may use liquefied gases as its working fluid) without discharging more hot cooling water (and no need for a cooling condenser), not generating thermal pollution, and no more radioactive pollution (which might be discharged from nuclear power plants) into the global environment.
An advantage of the present invention is that it is a more efficient heat engine process, with no need for a cooling condenser, and no waste thermal pollution. It just uses compressing power partially from turbines to push those condensed phase streams back into the boiler by the smaller pistons of the compressor/pump.
Another advantage of the present invention is the flexibility of the heat engine process (without condenser). It may use liquefied gases (oxygen or nitrogen) as its working fluid transferring energy and extracting work for this new air conditioner and new refrigerator system, in which it can have more temperature gradient, less heat transferring surface area, and shorter heat transfer time, and smaller heat exchanger size (smaller boiler).
Another advantage of the present invention is the two-phase separator flexibility. If water is chosen to be the working fluid, liquid oil will be sprayed into the condensed steam phase to scrub water particles down. The thick liquid oil layer is also responsible for covering the water surface to separate and prevent covered water from re-evaporating. If liquefied gas (oxygen or nitrogen) is chosen to be the working fluid, liquefied methane will be sprayed into the condensed phase (oxygen or nitrogen) to scrub liquid particles down. And thick liquefied methane layer is responsible for separating gas/liquid (oxygen or nitrogen) phases.
Yet another advantage of the present compressor is its piston area being much smaller than the two-phase turbine surface area, so that this smaller piston takes power partially from the turbine power, and pushes the waste, low-temperature streams back into the higher pressure boiler. The compressing power is extracted from that turbine power, from which the compressing power is much less than that.
Turbines force F_large=Pressure_medArea_large>>compressor force F_med=Pressure_highArea_smallArea_{large turbines'}>>> Area_{small piston's}; Pressure_{turbines' med}<Pressure_{piston's higher}
The present invention is a cyclic process, whose effect can generate power from the ambient temperature of solar energy and also cool down the surrounding temperature lower than room temperature (transfer heat energy into work from solar energy (by using liquefied gases (oxygen or nitrogen) as its working fluid). It is meant that the surrounding dissipates heat by contacting with the colder working fluid to have the surrounding temperature cooled down to lower than its room temperature (as a new air conditioner from this new heat engine process). Then, this new heat engine process compresses the waste streams back to the boiler (a place to restore heat), directly from a two-phase separator, without discarding waste heat into heat sink as the thermal pollution or unwanted thermal load.
This new high efficient heat engine process can use either water or liquefied gases for its working fluid by using (1) slower-speed-balanced turbines attached with a high ratio gear reducer to increase its generator's speed and meet its power generation requirements, and (2) two-phase separator/compressor/pump to compress the waste gas and liquid phases back into the higher pressure boiler.
This new invention provides improvements over the conventional steam engine, air conditioner, and refrigeration processes. And this new two-phase separator compressor/pump can compress the lower-temperature condensed-streams directly back into the boiler without using the conventional cooling condenser taking out the latent heat from the system and losing its power efficiency.
This new heat engine process can let the steam engine have close to 50% efficiency, and can also let the air conditioner and refrigerator produce power with this high efficiency, which also use a smaller heat transfer surface.
This new heat engine process will have higher efficiency of close to 50%, and can produce power and cool down surrounding's temperatures lower than the room temperature. This powerful heat engine process can use either water or liquefied gases for its working fluid at low temperatures without damaging the environment (no chemical refrigerants leaking, no hot cooling water discharge, no thermal pollution, and no radioactive or hazardous waste).

IV. BRIEF DESCRIPTION OF THE DRAWINGS

The invention may take physical form in certain parts and arrangement of parts, embodiments of which will be described in detail in this specification and illustrated in the accompanying drawings which form a part hereof and wherein:

FIG. 1 is a schematic diagram of the conventional heat engine process (with its cooling condenser);

FIG. 1A is a thermodynamic diagram of the conventional heat engine process (with its cooling condenser);

FIG. 2 is a schematic diagram of the conventional heat pump process (with its cooling condenser);

FIG. 2A is a thermodynamic diagram of the conventional heat pump process (with its cooling condenser);

FIG. 3 is a schematic diagram of the inventive heat engine process with the two-phase running turbines and the two-phase separator/compressor/pump (without the cooling condenser);

FIG. 3A is a thermodynamic diagram of the inventive heat engine process with the two-phase running turbines and the two-phase separator/compressor/pump (without the cooling condenser);

FIG. 4 is a schematic diagram of the new two-phase, slower-running turbines attached with a high ratio gear reducer to increase its generator's speed and meet its power generation requirements; and,

FIG. 5 is a schematic diagram of the new two-phase separator.

V. DETAILED DESCRIPTION

With reference now to FIGS. 1-2A, the conventional heat engine process includes a superheated steam boiler [11], superheated steam turbines [12], cooling condenser [13], and pump [14]. The conventional heat pump process includes a freezer [21], compressor [24], cooling condenser [23], and liquid-to-gas expansion valve [22].
With reference now to FIG. 3, the present new heat engine (and heat pump) processes include a saturated steam boiler [31], two-phase turbines [32], two-phase separator [33], compressor [35], and pump [14]. If we use liquefied oxygen or nitrogen as the boiler's [31] working fluid, the ambient energy may supply its heat (enthalpy) [38] to the boiler [31] and the ambient air energy will be extracted [38] (for evaporating the liquid nitrogen), then it cools down to below the room temperature, which effect is just like the new air conditioning effect [38], but it runs in a clockwise heat engine cycle.
The high ratio gear reducer [42] increases speed to the generator [43]. Two-phase turbines are usually used at lower speeds. The gear reducer [42] operates the generator [43] at a very high speed, and is attached to the turbines [41], which allows the turbine [41] to spin at a slower speed. In one embodiment of the invention, the turbine [41] has a rotation speed of between approximately 120 rpm and approximately 360 rpm, and the gear reducer [42] has a ratio of between approximately 1:10 to approximately 1:30. As long as the speed of the generator [43] (after being affected by the gear reducer [42]) is approximately 3600 rpm, and the high efficiency turbines [41] with a high ratio of the reducer [42] can be used. The two-phase turbines [41] generate high-efficiency work from the saturated vapor phase, but there would be the lower efficiency for conventional methods of generating work from the superheated gas phase. The turbine [32] goes through the gear reducer [42], which creates a high speed for the generator [43], which creates work. In FIG. 4, the slower-speed two-phase turbines [41] uses a high ratio gear reducer [42] to increase its generator's [43] speed and meet its power requirements. The condensed phase exit [44] is connected to the two-phase separator [33]. In FIG. 5, the two-phase separator has a condensed phase inlet [51], an oil or liquefied methane spraying inlet [52], a centrifuge device [53], an oil or liquid methane covering layer [54], a vapor phase outlet [55], the liquid phase [57], and a liquid phase outlet [56].
The phase separator [33], when the working fluid is water, separates the water droplets from the steam. Liquid oil will be on top of the water, separating the water from the steam. A centrifuge [53] is used to separate the vapor and liquid phases. If the working fluid is liquid nitrogen or oxygen, liquid methane will be on top of the liquid nitrogen or oxygen in the phase separator [33], separating the liquid nitrogen or oxygen from the nitrogen or oxygen gas.
A two-phase separator [33] is set after the turbine process. In this two-phase separator [33], liquid oil is sprayed into the condensed steam to scrub water particles down. Then, the steam phase and the water/oil phase are centrifuged and separated by a thick-layer of liquid oil phase preventing the water from re-evaporating. The compressing processes include a high pressure vapor compressor [35] and a small piston, a high pressure water pump [14] to pump waste streams back into the boiler [31] to complete this heat engine cycle's function (generate power at lower temperatures) without using the conventional cooling condenser at low temperatures.
This lower temperature heat engine process produces power by using either saturated steam or saturated liquefied gases for its working fluid, which can be liquefied oxygen, or nitrogen. These low temperature working fluids can easily absorb the energy from their ambient/non-ambient heat sources [38] with a higher heat transfer rate and higher efficiency, and then, the ambient heat source will be cool down to below the room temperature to become the so-called “air conditioning's cold air.” In one embodiment, the steam operating temperature is approximately from 500° F. (260° C.) to 600° F. (315° C.). And the liquefied oxygen operating temperature is approximately 120 K (−153° C.). The liquefied nitrogen's operating temperature is approximately 100 K (−173° C.) as the designated working fluid.
After the working fluid absorbs heat from the ambient/non-ambient heat sources, the liquid phase is evaporated into the high pressure saturated vapor. This higher pressure saturated vapor is used to generate power through the two-phase turbines [41], whose blades [41] are designed to be durable and balanced to rotate at a slow speed with better stability, less ball-bearing friction, and less heat fatigue. These slow turbines [41] are attached to a high ratio gear reducer [42] to increase its generator's speed and meet its power generation requirements (3,600 RPM).
After the saturated vapor stream has gone through the turbines [32], work is extracted out from this higher pressure stream. Because work has already been extracted out from this saturated vapor stream, this stream's pressure and temperature will drop into low pressure and low temperatures (a condensed two-phase stream). Then, these partially condensed-phase streams flow into a phase separator [33].
A two-phase separator [33] is set after the turbine process. In this two-phase separator [33], liquid oil is sprayed into the condensed steam phase to scrub water particles down. Then, the steam phase and the water/oil phase are centrifuged and separated by a thick-layer of liquid oil phase covering water from re-evaporating.
The compressing processes include a high pressure vapor compressor and a small piston, high pressure liquid/pump [14] to pump the waste streams back into the boiler [31] in order to complete this heat engine's cycle function (generating power at lower temperatures) without using the conventional cooling condenser at a lower temperature.
The compressor [35]/pump [14] use smaller pistons with higher pressure to compress these two-phase waste streams by less power, which is partially from the turbine [32], back into the boiler [31] to complete its heat engine process cycle.
There is no cooling condenser needed in this new heat engine process. While this condensed two-phase stream is going into the two-phase separator/compressor [33, 35], the compressor/pump [35, 14] compress these waste streams directly back into the boiler [31]. Therefore, there will be no more waste heat dropping from the lower temperature waste stream into the surroundings. There will be no more need for a cooling condenser.
This compressor's [35] smaller piston with higher pressure needs the less power from the turbine power source, which is shown in the following:
Turbines force F_large=Pressure_medArea_large>>compressor force F_med=Pressure_highArea_smallArea_{large turbines'}>>> Area_{small piston's}; Pressure_{turbines' med}<Pressure_{piston's higher}
The foregoing descriptions of specific innovations of the present invention are presented for purposes of illustration and applications. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above disclosure. It is intended that the scope of the invention is defined by the claims appended hereto and their equivalents. Therefore, the scope of the invention is to be limited only by the following claims.
Having thus described the invention, it is now claimed:

Claims

1. A method for heat transfer, wherein the method utilizes a boiler, a two-phase turbine, two-phase separator, and compressor/pump, wherein the method has a vapor phase and a liquid phase, the method comprising the steps of:

absorbing ambient/non-ambient thermal energy;

generating a high pressure saturated vapor stream from the boiler;

extracting practical work from the high pressure saturated vapor stream via the associated two-phase turbine;

separating a condensed phase by spraying oil or liquefied methane and scraping liquid droplets from a condensed stream;

covering and preventing the liquid phase from re-evaporating; and,

compressing/pumping waste gas/liquid phases back into the boiler through at least one compressor/pump without loss of heat into a heat sink, wherein the method does not use a cooling condenser.

2. The method of claim 1, wherein a working fluid of the boiler is chosen from the group comprising water, liquefied oxygen, or nitrogen, wherein the working fluid is not a hazardous chemical.

3. The method of claim 1, wherein the two-phase turbine comprises a slower-speed turbine of blades with a large surface area.

4. The method of claim 3, wherein the slower-speed turbine comprises a high ratio gear reducer to increase speed to a generator and meet the generator's power generation requirements.

5. The method of claim 1, wherein the step of separating a condensed phase by spraying oil or liquefied methane and scraping liquid droplets from a condensed stream comprises:

separating a condensed phase by spraying oil/or liquefied methane, scraping liquid droplets from the condensed phase, and centrifuging.

6. The method of claim 1, wherein the step of compressing/pumping waste gas/liquid phases back into the boiler through at least one compressor/pump without loss of heat into a heat sink comprises:

compressing/pumping the gas/liquid streams directly back into the boiler separately without discarding heat into the heat sink.

7. A low-temperature heat engine device comprising:

at least one low-temperature liquefied gas boiler;

at least one two-phase turbine;

at least one high ratio gear reducer;

at least one two-phase separator;

at least one gas compressor; and,

at least one liquid pump, wherein the device does not have a cooling condenser.

8. The device of claim 7, wherein the two-phase turbine has a rotation speed of between approximately 120 rpm to approximately 360 rpm.

9. The device of claim 8, wherein the turbine has a large surface area.

10. The device of claim 7, wherein the high ratio gear reducer is connected to the two-phase turbine.

11. The device of claim 7, wherein the high ratio gear reducer is operatively connected between the turbine and a generator to increase speed to the generator.

12. The device of claim 11, wherein the gear reducer and generator rotate at a rate higher than those of the turbine.

13. The device of claim 8, wherein the gear reducer has a ratio of between approximately 1:10 to approximately 1:30.

14. The device of claim 13, wherein the generator has a rotation speed of approximately 3600 rpm.