# Patent

## Title
System and method for managing thermal issues in one or more industrial processes

## Abstract

The present invention generally relates to a system that enables one to both: (i) address various thermal management issues (e.g., inlet air cooling) in gas turbines, gas turbine engines, industrial process equipment and/or internal combustion engines; and (ii) yield a supercritical fluid-based heat engine. In one embodiment, the present invention utilizes at least one working fluid selected from ammonia, carbon dioxide, nitrogen, or other suitable working fluid medium. In another embodiment, the present invention utilizes carbon dioxide or ammonia as a working fluid to achieve a system that enables one to address inlet cooling issues in a gas turbine, internal combustion engine or other industrial application while also yielding a supercritical fluid based heat engine as a second cycle using the waste heat from the gas turbine and/or internal combustion engine to create a combined power cycle.

## Background
RELATED APPLICATION DATA
This patent application claims priority to U.S. Provisional Patent Application No. 61/219,1956, filed on Jun. 22, 2009, entitled “System and Method for Managing Thermal Issues in Gas Turbine Engines,” the entirety of which is hereby incorporated by reference herein.


FIELD OF THE INVENTION
The present invention generally relates to a system that enables one to both: (i) address various thermal management issues (e.g., inlet air cooling) in gas turbines, gas turbine engines, industrial process equipment and/or internal combustion engines; and (ii) yield a supercritical fluid-based heat engine. In one embodiment, the present invention utilizes at least one working fluid selected from ammonia, carbon dioxide, nitrogen, or other suitable working fluid medium. In another embodiment, the present invention utilizes carbon dioxide or ammonia as a working fluid to achieve a system that enables one to address inlet cooling issues in a gas turbine, internal combustion engine or other industrial application while also yielding a supercritical fluid based heat engine as a second cycle using the waste heat from the gas turbine and/or internal combustion engine to create a combined power cycle.
BACKGROUND OF THE INVENTION
Various approaches have been suggested to address various thermal management issues (e.g., inlet air cooling, waste heat recovery) in gas turbines, gas turbine engines, internal combustion engines and other industrial processes. Such approaches include those discussed in the report entitled Experimental and Theoretical Investigations of New Power Cycles and Advanced Falling Film Heat Exchangers by the U.S. Department of Energy in conjunction with the University of New Mexico.
In this report two new thermodynamic cycles were proposed and investigated based on the second law of thermodynamics. Two computer programs were developed to find effect of important system parameters on the irreversibility distribution of all components in the cycle: (1) the first cycle was based on a combined triple (Brayton/Rankine/Rankine)/(Gas/steam/ammonia) cycle capable of producing high efficiencies; and (2) the second cycle is a combined (Brayton/Rankine)/(gas/ammonia) cycle with integrated compressor inlet air-cooling capable of producing high power and efficiency. The proposed cycles and the results obtained from the second law analyses of the cycles were published in Energy Conversion and Management and ASME proceedings (IMEC&E 2001).
Given the above, there is a need in the art for systems that are designed to address various thermal management issues for various devices (e.g., gas turbines, gas turbine engines, industrial process equipment and/or internal combustion engines). In one instance, there is a need for a system that is able to address various thermal management issues (e.g., inlet air cooling) in gas turbines, gas turbine engines, internal combustion engines and/or other industrial process equipment.
SUMMARY OF THE INVENTION
The present invention generally relates to a system that enables one to both: (i) address various thermal management issues (e.g., inlet air cooling) in gas turbines, gas turbine engines, industrial process equipment and/or internal combustion engines; and (ii) yield a supercritical fluid-based heat engine. In one embodiment, the present invention utilizes at least one working fluid selected from ammonia, carbon dioxide, nitrogen, or other suitable working fluid medium. In another embodiment, the present invention utilizes carbon dioxide or ammonia as a working fluid to achieve a system that enables one to address inlet cooling issues in a gas turbine, internal combustion engine or other industrial application while also yielding a supercritical fluid based heat engine as a second cycle using the waste heat from the gas turbine and/or internal combustion engine to create a combined power cycle.
In one embodiment, the present invention relates to a system that is designed to both achieve inlet air cooling in gas turbines, gas turbine engines, internal combustion engines and/or other industrial processes (e.g., gas or air compression) while also yielding a supercritical fluid-based heat engine as a second cycle using the waste heat from the gas turbine, internal combustion engine, and/or other industrial process to create a combined power cycle as shown and described herein.
In another embodiment, the present invention relates to a system for temperature conditioning inlet air for a turbine comprising: at least one turbine having an inlet side and an outlet side; at least one air inlet heat exchanger operatively coupled to the inlet side of the at least one turbine, wherein the at least one air inlet heat exchanger is designed to remove heat from inlet air being supplied to the inlet side of the at least one turbine and transfer such heat via a working fluid to a bottom loop; at least one air outlet heat exchanger operatively coupled to the outlet side of the at least one turbine, wherein the at least one air outlet heat exchanger is designed to remove heat from outlet air being generated by the at least one turbine and transfer such heat via a working fluid to the bottom loop; wherein the bottom loop is designed to utilize such transferred heat from the at least one air inlet heat exchanger and the at least one air outlet heat exchanger to provide suitably conditioned working fluid back to both the at least one air inlet heat exchanger and the at least one air outlet heat exchanger.
In still another embodiment, the present invention relates to a method for temperature conditioning inlet air for a turbine, the method comprising the steps of: providing at least one turbine having an inlet side and an outlet side; providing at least one air inlet heat exchanger operatively coupled to the inlet side of the at least one turbine, wherein the at least one air inlet heat exchanger is designed to remove heat from inlet air being supplied to the inlet side of the at least one turbine and transfer such heat via a working fluid to a bottom loop; providing at least one air outlet heat exchanger operatively coupled to the outlet side of the at least one turbine, wherein the at least one air outlet heat exchanger is designed to remove heat from outlet air being generated by the at least one turbine and transfer such heat via a working fluid to the bottom loop; wherein the bottom loop transfers heat from the at least one air inlet heat exchanger and the at least one air outlet heat exchanger to provide suitably conditioned working fluid back to both the at least one air inlet heat exchanger and the at least one air outlet heat exchanger.
In still yet another embodiment, the present invention relates to a system for temperature conditioning air comprising: at least one heat source; at least one first heat exchanger operatively coupled to the at least one heat source and designed to remove and/or utilize waste heat from the heat source to transfer such heat to a working fluid; at least one compressor operatively coupled via the working fluid to the at least one first heat exchanger, wherein the at least one compressor is designed receive the heat-laden working fluid generated by the at least one first heat exchanger and to utilize, or bleed heat from, the heat laden working fluid so as to yield a cooled working fluid; at least one second heat exchanger operatively coupled to the at least one compressor, wherein the at least one second heat exchanger is designed to receive the cooled working fluid and to utilize the cooled working fluid to remove heat from, or condition the temperature of, air.



BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an illustration of a system in accordance with one embodiment of the present invention;
FIG. 2 is an illustration of another system in accordance with one embodiment of the present invention;
FIG. 3 is an illustration of another system in accordance with one embodiment of the present invention;
FIG. 4 is an illustration of another system in accordance with one embodiment of the present invention; and
FIG. 5 is an illustration of another system in accordance with one embodiment of the present invention.



DETAILED DESCRIPTION OF THE INVENTION
The present invention generally relates to a system that enables one to both: (i) address various thermal management issues (e.g., inlet air cooling) in gas turbines, gas turbine engines, industrial process equipment and/or internal combustion engines; and (ii) yield a supercritical fluid-based heat engine. In one embodiment, the present invention utilizes at least one working fluid selected from ammonia, carbon dioxide, nitrogen, or other suitable working fluid medium. In another embodiment, the present invention utilizes carbon dioxide or ammonia as a working fluid to achieve a system that enables one to address inlet cooling issues in a gas turbine, internal combustion engine or other industrial application while also yielding a supercritical fluid based heat engine as a second cycle using the waste heat from the gas turbine and/or internal combustion engine to create a combined power cycle.
In one embodiment, the purpose of the present invention is twofold: (i) to act as a supercritical fluid-based heat engine as a second cycle using the waste heat from a gas turbine and/or internal combustion engine (ICE) to create a combined power cycle; and (ii) to have an integrated solution for gas turbine/ICE inlet air cooling (schematic attached). In this embodiment, the present invention is designed to be primarily a bottom cycle heat engine with a dynamic vapor compression chilling component that can be used when higher ambient conditions are encountered and thus increase overall output of combined cycle. In another embodiment, the supercritical fluid-based cycle can be used to provide intake charge cooling for an air or gas compression device, thus reducing the thermodynamic work required for compression. The heat input for this process could in whole or in part be provided by the waste heat of compression.
In one embodiment, the present invention will be described in relation to a General Electric GE-10 gas turbine. However, the present invention is not limited thereto. Rather the present invention can be applied to any suitable turbine, gas turbine, industrial process equipment and/or internal combustion engine. Given this, the predicted performance for the embodiment of FIG. 1 involves the working conditions of a General Electric GE-10 gas turbine and the advantages gained by utilizing an integrated system in accordance with one embodiment of the present invention. For illustrative purposes, up to 28 percent of a typically gas turbine's (e.g., a GE-10) power is lost when the ambient temperature rises from 15° C. (59° F.) to 45° C. (113° F.). At the same time, the cost of electricity can increase substantially during hot days due to increased demand from residential and commercial air conditioning. The performance decrease of the gas turbine also leads to decreased performance of the second cycle performance. For example, a 5.0 percent decrease in output power occurs in a NH3 second cycle the exemplar GE10 over the aforementioned temperature variance/difference.
Regarding the embodiment where the present invention is applied to a General Electric 10 (GE-10) gas turbine, the example calculations herein involve a GE-10 gas turbine operating at 15° C. (59° F.) and 30° C. (86° F.) ambient temperatures. The flue gas temperature of the gas turbine per the GE-10 operating specifications is 489.5° C. (914° F.) and 505° C. (941° F.) at 15° C. (59° F.) and 30° C. (86° F.) ambient, respectively. The flue gas mass flows without inlet cooling at these two ambient conditions are 47 kg/s (373,086 lbs/hr) and 42 kg/s (333,396 lbs/hr) respectively. The flue gas mass flow rate for the integrated inlet cooled condition matches the 15° C. (59° F.) situation. The amount of intake air for the integrated inlet cooled condition is determined by removing the mass of natural gas needed based on the prescribed heat rate and 9,570 kJ/kg (20,000 btu/lb) for natural gas. The incoming air flow rate used for the integrated solution is 46.2 kg/s (366,966 lbs/hr).
The performance of an ammonia-driven second cycle using the waste heat from the GE-10 at 15° C. (59° F.) will add 3,310 kW of net energy to an 11,250 kW output of a GE-10 gas turbine equating to a combined cycle output of 14,560 kW. This equates to a 29.4 percent increase in power over a single cycle. Without inlet cooling at the 30° C. (86° F.) ambient condition, the amount of power delivered by the second cycle decreases to 3,189 kW at 30° C. (86° F.). Combined with a drop in the gas turbine rated power to 10,000 kW, the total power output from the combined cycle decreases by 9.4 percent. The decrease in the second cycle output power is a direct result of the decrease in gas turbine power.
When adding the integrated cooling cycle, the gas turbine power no longer drops to 10,000 kW but remains at 11,250 kW due to the consistent 15° C. (59° F.) inlet air temperature regardless of ambient temperature. In addition, the heat rate of the simple cycle remains at 11,500 kJ/kW-hr (10,900 Btu/kW-hr) as opposed to increasing to 12,100 kJ/kW-hr (11,374 Btu/kW-hr) at 30° C. (86° F.). The second cycle output drops to 3,123 kW due to the addition of the compressor energy. The increase in gas turbine performance plus the ammonia second cycle output leads to a combined cycle output of 14,374 kW; an 9.0 percent increase on the 30° C. (86° F.) day over the basic ammonia combined cycle and a 45.1 percent increase on simple cycle performance at the same ambient temperature.
In the instance where an ammonia working fluid is utilized in connection with a GE-10, some variations in operating conditions can include the following: high side pressures typically range from 10.3-20.7 MPa (1500-3000 psia), high side temperatures typically range from 149° C.-482° C. (300-900° F.), low side heat engine pressures typically range from 2.1-4.2 MPa (300-600 psia), refrigeration pressures typically range from 0.1-0.69 MPa (14.7-100 psia) and ambient conditions as high as 50° C. (12° F.). Given this, the present invention is not restricted to any one set of operating conditions, nor to a particular working fluid. Rather, the present invention, as would be appreciated by one of skill in the art, can be designed to operate across a broad range of various conditions, and with several different working fluids. As such, the present invention is to be broadly construed in light of the disclosure contained herein.
In one embodiment, the present invention yields various advantages including, but not limited to, (i) the use of supercritical fluid removes the temperature pinch point that is involved with vaporization as well as the issues dealing with two phase flow; (ii) the use of supercritical fluid will lead to a waste heat exchanger design that allows for higher working fluid temperatures relative to a single pressure steam-based heat recovery steam generator; (iii) the use of supercritical carbon dioxide or ammonia allows for an operation of a cycle in which there is no condensing within the turbine without the addition of a superheater.
The present invention also permits one to achieve consistent mass flow through the power cycle while generating a variable amount of refrigeration for the inlet cooler as the ambient temperature changes. In one embodiment, this is achieved by removing the refrigerant after the power cycle's condensing step and reintroducing it prior to the pump. One advantage of this is that the power cycle, which will be running at all times, will remain at the same operating point at all times in terms of pressures, mass flow as well as temperatures. This consistency of operation will allow all components to perform optimally and thus keep the cycle efficiency at its design point. As the need for refrigerant is increased on hot days, working fluid will be removed from the low-pressure side of the system, but will be reintroduced in a usable form prior to the pump without affecting the power cycle.
Additionally, the present invention enables one to take a side stream of working fluid from any point on the high pressure portion of the power generation cycle and use that for an ejector on the cooling cycle. This will allow for a lower cost component as well as the avoidance of decreased performance due to compressor motor efficiencies (there will still be an efficiency loss associated with the ejector).
Additionally, in another embodiment, the present invention enables any nitrogen and hydrogen constituents that may be created within the ammonia-based process to be separated out and do one or more of the following with said nitrogen and/or hydrogen: (i) regenerate ammonia through the Haber process and add generated ammonia back to system; (ii) collect the free hydrogen and use as feed stock for combustion and/or fuel cell; (iii) collect hydrogen and nitrogen separately and collect for commercial consumption; and/or (iv) vent the nitrogen and flare the hydrogen. It should be noted that items (i) to (iv) above are exemplary in nature and many other potential uses for any such nitrogen and/or hydrogen generated by the systems of the present invention exist but are not enumerated here for the sake of brevity.
The present invention also enables one to recycle flue gas from the back end of the gas turbine to the inlet thereby achieving an increased ability to capture CO2 emissions from the gas turbine by providing a more concentrated CO2 stream, and to reduce NOX emissions through reduction in peak flame temperature. The main road block to this process is the high temperature at which the recycled flue gas, up to 40 percent of the flue gas flow, would be re-introduced to the inlet. The integrated solution of the present invention and illustrated in FIG. 1 eliminates this problem in several ways. First, the flue gas will already be cooled to a lower temperature from the heat exchanger removing heat for the power generation cycle. Second, an increase in refrigerant can be sent to the inlet air to offset any temperature increase introduced by the recycled flue gas. Third, the recuperator can be decreased in effectiveness thus allowing more energy to be removed from the flue gas. This will allow for a lower flue gas temperature and can then be added to the inlet of the gas turbine without effecting performance.
The present invention also enables one to integrate current ammonia based selective catalytic reducers (SCR) with the ammonia based heat engine. SCR units are used with gas turbines in order to reduce NOx emissions to meet EPA standards. A side stream of ammonia can be removed from anywhere in the system and injected into the flue gas stream with a makeup system adding ammonia back to the heat engine prior to the pump.
FIG. 1 discloses a system 100 in accordance with one embodiment of the present invention. In system 100, ammonia is utilized to achieve a system that enables one to address inlet cooling issues in a gas turbine and/or an internal combustion engine while also yielding a supercritical ammonia based heat engine as a second cycle using the waste heat from the gas turbine and/or internal combustion engine to create a combined power cycle. As is illustrated in FIG. 1, system 100 includes a heat exchanger 102 that is designed to lower the inlet temperature of air supplied to turbine 104. Turbine 104 can be any suitable turbine including, but not limited to, a gas turbine. In one embodiment, turbine 104 is composed of compressor 106, combustor 108 and turbine 110. As should be recognized by those of skill in the art, the present invention is not limited to just a gas turbine, or to a gas turbine having the afore-mentioned configuration. Rather, the present invention is to be broadly construed and is applicable to a wide range of air-breathing engines, or other industrial processes such as gas or air compression, where the temperature control of inlet air is desired. As used herein, any compressor utilized in conjunction with the embodiments of the present invention can be independently selected from a mechanical compressor or a fluid compressor (e.g., an ejector).
Regarding heat exchanger 102, any suitable heat exchanger can be used including, but not limited to, one or more heat exchangers that each contain therein one or more cores where each core utilizes microchannel technology.
As used herein, “microchannel technology” includes, but is not limited to, heat exchangers that contain one or more microchannels, mesochannels, and/or minichannels. As used herein the terms “microchannels,” “mesochannels,” and/or “minichannels” are utilized interchangeably. Additionally, the microchannels, mesochannels, and/or minichannels of the present invention are not limited to any one particular size, width and/or length. Any suitable size, width or length can be utilized depending upon a variety of factors. Furthermore, any orientation of the microchannels, mesochannels, and/or minichannels can be utilized in conjunction with the various embodiments of the present invention.
In another embodiment, a heat exchanger in accordance with the present invention can be formed with one or more cores having one or more printed circuit heat exchange (PCHE) panels. Such panels are known in the art, and are described in U.S. Pat. Nos. 6,921,518; 7,022,294; and 7,033,553, all of which are incorporated herein by reference, in their entireties, for their teachings related to printed circuit heat exchange (PCHE) panels. Other suitable heat exchangers for use as a regenerator in the system of FIG. 1 are disclosed in United States Published Patent Application No. 2006/0254759, the disclosure of which is incorporated herein in its entirety.
In still another embodiment, any type of heat exchanger known to those of skill in the art can be utilized herein so long as such heat exchanger has the capacity to manage and/or meet the thermal requirements of the system in which it is incorporated. In still yet another embodiment, the present invention is not only concerned with providing a system that enables one to address various thermal management issues in advanced gas turbine engines but also to a system that is designed to address power management issues.
Regarding turbine 104, flue gases therefrom are supplied by any suitable conveyance means to another heat exchanger 112. Regarding heat exchanger 112, this heat exchanger can be selected from heat exchangers similar to those discussed above with regard to heat exchanger 102. Additionally, as is illustrated in FIG. 1, inlet air is cooled by heat exchanger 102 and supplied to turbine 104 via any suitable conveyance means. In turn, the sub-components of turbine 104 are also suitably connected as is known to those of skill in the art. Regarding suitable conveyance means, such means include, but are not limited to, conduits, pipes, ducts, flues, etc. that are designed to withstand the various environmental conditions experienced in the turbine applications disclosed herein. Such design criteria are not discussed herein for the sake of brevity as they are well known to those of skill in the art.
As can be seen in the embodiment of FIG. 1, system 100 utilizes a suitable working fluid in combination with various heat exchangers and suitable conveyance means to pull “heat” from inlet air that enters heat exchanger 102 thereby yielding cooled inlet air to turbine 104. Regarding system 100 of FIG. 1, the working fluid can be any suitable working fluid including, but not limited to, ammonia, carbon dioxide (be it supercritical or otherwise), nitrogen, inert working fluids, or any suitable combination of two or more thereof. In one instance, the system of FIG. 1 utilizes an ammonia working fluid. As will be appreciated upon reading and understanding FIG. 1, the working fluid of the present invention is not always in a liquid state. Rather, as would be apparent to those of skill in the art, the working fluid of the present invention undergoes various phase changes in order to accomplish the stated goals of system 100.
As can be seen in FIG. 1, system 100 contains various additional heat exchangers (e.g., heat exchangers 114, 116, 118 and 120), at least one additional compressor (e.g., 122), at least one additional expander (e.g., 124), a suitable number of valves (e.g., 128), a static mixer (e.g., 126), at least one pump (e.g., 130) and at least one expansion valve (e.g., 132). As would be appreciated by those of skill in the art, the process parameters detailed in FIG. 1 are exemplary in nature and in no way are meant to limit the scope of the present invention. Rather, the present invention is broadly applicable to a wide range of situations where it is desired to “pull” heat from one point, or area, of a system and “move” it to another point, or area.
In another embodiment, static mixer 126 can be modified as follows. The mixer 126 could be designed to have low temperature liquid coming in the top, high temperature vapor coming in from suitable point in the middle with any additional cooling needed for condensing being added. This condensing could be integrated with heat exchangers 114 and 116. All condensed liquid will be pulled off the bottom.
Regarding the additional components in the two bottom loops of system 100, the various additional heat exchangers can be selected from the heat exchangers discussed above. The at least one additional compressor (e.g., 122), the at least one additional expander (e.g., 124), the valves (e.g., 126 and 128), the at least one pump (e.g., 130) and the at least one expansion valve (e.g., 132) can be selected from a wide range of known components of these types that are available on the market, or can be purpose-designed for the disclosed system. Again, the additional components of the bottom loops of FIG. 1 are connected via suitable conveyance means selected from those discussed above. The type of components selected in this case will depend on the exact design specifications of the system to be created.
One such arrangement for all of the above identified components of system 100 is illustrated in FIG. 1. In FIG. 1, system 100 is utilized to reduce the temperature of inlet air from an ambient of, for example, 86° F. to 59° F. This is accomplished by utilizing heat exchanger 102 and a working fluid that is supplied to heat exchanger 102. The reduced temperature air is then supplied as inlet air to turbine 104 which is designed to burn fuel (e.g., natural gas, coal or oil) and supply exhaust gas and waste heat to heat exchanger 112.
In another embodiment, various components of system 100 can be eliminated to yield a simplified system depending upon the goal to be accomplished. Alternatively, various components of system 100 can be replaced by control valves and an ejector. FIG. 3 is an illustration of a system 300 showing the ejector 334 in place of compressor 122 from FIG. 1. The driving fluid for the ejector can be derived from prior to heat exchanger 318, prior to heat exchanger 312 or prior to expander 324. A control valve will be added to the system at the optimal point for removing fluid to act as the driving fluid for the ejector.
In another embodiment, components can be added to system 100 in order to separate and collect any hydrogen or nitrogen gas created during thermal cycling of the ammonia working fluid within the heat engine. FIG. 4 is an illustration of a system 400 which uses the same heat engine and inlet cooling as FIG. 1. However, system 400 includes a Haber process reactor to regenerate ammonia. FIG. 4 shows the addition of flash tank 434 which separates gaseous nitrogen and hydrogen still present after ammonia condensing step in heat exchanger 420. Gaseous nitrogen and hydrogen are separated in flash tank 434 and supplied to compressor 436 where they are compressed to reaction pressure. Compressed nitrogen and hydrogen are delivered to a catalytic reactor 438 with the product being gaseous ammonia and excess nitrogen and hydrogen being recycled to the front end of the reactor. Heat will need to be delivered to catalytic reactor 438, this could come from an external source or from internal waste heat. This ammonia is expanded through expansion valve 440 to the low side operating pressure of the heat engine. The expanded fluid is combined with compressed gas valve 442. All other components within FIG. 4 are consistent with FIG. 1. In still another embodiment, system 400 can be designed to utilize a CO2 Brayton or Rankine top cycle to handle the direct exchange from a gas turbine exhaust (FIG. 5).
FIG. 2 is an illustration of a system 200 in accordance with another embodiment of the present invention where exit gases of turbine 204 are cooled using a working fluid based system in accordance with the present invention. In one embodiment, the working fluid is carbon dioxide. However, this embodiment is not limited thereto. Rather, any suitable working fluid, or combination of working fluids, can be utilized in connection with this embodiment. Turbine 204 of system 200 is composed of compressor 206, combustor 208 and turbine 210. Turbine 204 supplies flue gases to heat exchanger 212 which are then cooled and supplied for further cooling to heat exchanger 250. Heat exchangers 212 and 250 are connected to a double loop system that utilizes a working fluid selected from those discussed above to pull heat from the flue gases generated by turbine 204. As used herein, “turbine” is intended to mean a gas turbine, a gas turbine engine, an internal combustion engine, or any other item of industrial process equipment that produces exhaust and takes in air.
As shown in FIG. 2, system 200 includes at least one additional heat exchanger (e.g., 256 and 258), at least one additional compressor (e.g., 252), at least one additional expander (e.g., 254), various valves (e.g., 260 and 262), and at least one pump (e.g., 260). Again, the additional components of the bottom loops of FIG. 2 are connected via suitable conveyance means selected from those discussed above. The type of components selected in this case will depend on the exact design specifications of the system to be created.
As would be appreciated by those of skill in the art, the process parameters detailed in FIG. 2 are exemplary in nature and in no way are meant to limit the scope of the present invention. Rather, the present invention is broadly applicable to a wide range of situations where it is desired to “pull” heat from one point, or area, of a system and “move” it to another point, or area.
FIG. 5 is an illustration of yet another embodiment of the present invention where the present invention contains at least two distinct loops and each loop utilizes its own working fluid. In one instance, each loop can use the same or different working fluids. Suitable working fluids are chosen from those noted above. In another embodiment, different working fluids are utilized in each loop. In one instance, one loop utilizes CO2 as a working fluid and the other utilizes ammonia (NH3). As can be seen in FIG. 5 inlet air for a gas turbine is cooled using a dual cycle system where one cycle utilizes carbon dioxide as a working fluid and the other cycle utilizes ammonia as a working fluid. In this embodiment, the two cycles are interconnected via one heat exchanger.
The system 500 of FIG. 5 comprises a heat exchanger 502 that is positioned at the inlet end of a gas turbine 504, wherein heat exchanger 502 is of a type or design as discussed above and is able to utilize a working fluid to condition the temperature of an inlet gas (e.g., air) prior to entry of the inlet gas into gas turbine 504. Gas turbine 504 supplies waste heat to a waste heat exchanger 506 which is of a type or design as discussed above. Waste heat exchanger 506 is operatively coupled to a turbine 508 and a pump 510. As can be seen from FIG. 5, pump 510 is also operatively coupled to a condenser 512. Turbine 508, condenser 512 and a second turbine 514 are all operatively coupled to a heat exchanger 516 as is illustrated in FIG. 5. Turbine 514 is operatively coupled to a second condenser 518. Condenser 518 is, as is illustrated in FIG. 5, also operatively coupled to a compressor, or pump, 520, a expansion valve 522 and a second pump 524, as is illustrated in FIG. 5. Compressor, or pump, 520 and expansion valve 522 are also both operatively coupled to heat exchanger 502 in the manner illustrated in FIG. 5. Finally, in the embodiment of FIG. 5, second pump 524 is operatively coupled to heat exchanger 516 in a manner illustrated in FIG. 5.
Regarding FIGS. 1 through 5, these Figures illustrate embodiments of the present invention that are designed to achieve the simultaneous air, or gas, inlet cooling in combination with the utilization of waste heat from any industrial, or combustion, process. Given this, FIGS. 1 through 5 are illustrative of only exemplary embodiments of the present invention and thus, modifications of these embodiments are within the scope of the present invention and would be apparent to one of skill in the art.
Industrial, or combustion, processes that benefit from the systems of the present invention include any industrial, or combustion, processes where such a process becomes more efficient when a gas (e.g., air) is conditioned in such a manner as to increase its density and/or reduce its temperature. In one embodiment, such processes include, but are not limited to, those processes carried out by gas turbines, internal combustion engines, air compressors, gas compressors, or any combination thereof. In one embodiment, the present invention is advantageous in that it permits the temperature conditioning of an inlet gas in order to permit an increase in the operating efficiency of a device that is subject to performance degradation when the inlet temperature of the intake gas increases.
In still another embodiment, the present invention comprises a combination of a sub-system designed to achieve the temperature conditioning of a gas (e.g., an inlet gas or inlet air for an industrial process) with a sub-system designed to utilize waste heat to power the sub-system designed to achieve the temperature conditioning as well as, in some embodiments, permit the waste heat sub-system to generate additional usable energy or power that can be utilized for any desired purpose. Thus, in this embodiment, the waste heat sub-system of the present invention is sometimes referred to herein as a bottom loop, circuit, or cycle that utilizes a working fluid, as defined herein, to achieve the aforementioned goal(s). Accordingly, in one instance, the present invention achieves the integration of a sub-system designed to achieve the temperature conditioning of a gas (e.g., an inlet gas or inlet air for an industrial process) with a sub-system designed to utilize waste heat to drive the aforementioned temperature conditioning sub-system as well as to permit the waste heat sub-system to generate additional usable energy or power that can be utilized for any desired purpose. In one instance, this embodiment is achieved by a bottom loop (as can be seen in the bottom portions of FIGS. 1 through 5), that utilizes waste heat provided to the bottom loop to drive and accomplish the aforementioned temperature conditioning as well as operating as a heat engine that can generate, or produce, additional power, or energy, that can be exported out of the system and used for any desired purpose.
Regarding the temperatures and/or pressures disclosed in any, or all of, FIGS. 1 through 5, these temperatures and pressures are exemplary in nature. As would be apparent to those of skill in the art, depending upon the device and/or conditions to which the present invention is being applied such temperatures and pressures may, can or will change. Additionally, in some instances, the systems of the present invention will be transcritical or supercritical. As such, as would be known to those of skill in the art upon reading and understanding the present disclosure, some portions of the systems of the present invention will be sub-critical, while other portions will be supercritical. In fact, one aspect of the inventive system is that the working fluid may be a supercritical fluid, a sub-critical liquid and/or a sub-critical vapor in different locations within the inventive system.
Although the invention has been described in detail with particular reference to certain aspects detailed herein, other aspects can achieve the same results. Variations and modifications of the present invention will be obvious to those skilled in the art, and the present invention is intended to cover in the appended claims all such modifications and equivalents.

## Claims

1. A system for temperature conditioning inlet gas, comprising:
a gas turbine having an inlet side and an outlet side;
at least one gas inlet heat exchanger operatively coupled to the inlet side of the gas turbine, wherein the at least one gas inlet heat exchanger is configured to remove heat from inlet gas being supplied to the inlet side of the gas turbine prior to entry of the inlet gas into the gas turbine and transfer such heat via a working fluid to a bottom loop;
at least one gas outlet heat exchanger operatively coupled to the outlet side of the gas turbine and fluidly coupled with the bottom loop, wherein the at least one gas outlet heat exchanger is configured to remove heat from outlet gas being generated by the gas turbine and transfer such heat via the working fluid to the bottom loop,
wherein the bottom loop is configured to utilize such transferred heat from the at least one gas inlet heat exchanger and the at least one gas outlet heat exchanger to provide suitably conditioned working fluid back to both the at least one gas inlet heat exchanger and the at least one gas outlet heat exchanger, and comprises:
at least one bottom loop expander fluidly coupled to the at least one gas inlet heat exchanger and directly fluidly coupled to the at least one gas outlet heat exchanger, wherein the at least one bottom loop expander is configured to receive a heat-laden working fluid from the at least one gas outlet heat exchanger and yield a cooled working fluid; and
at least one bottom loop heat exchanger fluidly coupled with the at least one bottom loop expander, the at least one outlet heat exchanger, and the at least one gas inlet heat exchanger, wherein the at least one bottom loop heat exchanger is disposed downstream from the at least one bottom loop expander and upstream of the at least one gas inlet heat exchanger and the at least one gas outlet heat exchanger, the at least one bottom loop heat exchanger being configured to receive the cooled working fluid from the at least one bottom loop expander and transfer the cooled working fluid to the at least one gas inlet heat exchanger.

2. The system of claim 1, wherein the working fluid is selected from ammonia, carbon dioxide, or a combination thereof.

3. The system of claim 2, wherein the working fluid is carbon dioxide.

4. The system of claim 3, wherein the working fluid is supercritical carbon dioxide.

5. The system of claim 2, wherein the working fluid is ammonia.

6. The system of claim 5, wherein the working fluid is supercritical ammonia.

7. The system of claim 1, wherein the at least one gas inlet heat exchanger comprises microchannels.

8. The system of claim 1, wherein the at least one gas inlet heat exchanger comprises one or more printed circuit heat exchanger cores.

9. The system of claim 1, wherein the at least one gas outlet heat exchanger comprises microchannels.

10. The system of claim 1, wherein the at least one gas outlet heat exchanger comprises one or more printed circuit heat exchanger cores.

11. The system of claim 1, wherein the bottom loop is configured to utilize waste heat at the outlet side of the gas turbine in combination with the at least one gas inlet heat exchanger to yield a reduction in a temperature of the inlet gas provided to the inlet side of the gas turbine.

12. The system of claim 11, wherein and
the cooled working fluid from the at least one bottom loop heat exchanger is provided to the at least one gas inlet heat exchanger for use in the reduction of the temperature of the inlet gas provided to the inlet side of the gas turbine.

13. The system of claim 1, wherein the bottom loop is a heat engine configured to utilize transferred heat to condition the inlet gas and generate surplus power or energy.

14. The system of claim 1, wherein the inlet gas comprises air.

15. A method for temperature conditioning inlet gas, the method comprising:
providing a gas turbine having an inlet side and an outlet side;
providing at least one gas inlet heat exchanger operatively coupled to the inlet side of the gas turbine, wherein the at least one gas inlet heat exchanger is configured to remove heat from inlet gas being supplied to the inlet side of the gas turbine prior to entry of the inlet gas into the gas turbine and transfer such heat via a working fluid to a bottom loop; and
providing at least one gas outlet heat exchanger operatively coupled to the outlet side of the gas turbine, wherein the at least one gas outlet heat exchanger is configured to remove heat from outlet gas being generated by the gas turbine and transfer such heat via the working fluid to the bottom loop,
wherein the bottom loop transfers heat from the at least one gas inlet heat exchanger and the at least one gas outlet heat exchanger to provide suitably conditioned working fluid back to both the at least one gas inlet heat exchanger and the at least one gas outlet heat exchanger, and comprises:
at least one bottom loop expander fluidly coupled to the at least one gas inlet heat exchanger and directly fluidly coupled to the at least one gas outlet heat exchanger, wherein the at least one bottom loop expander is configured to receive a heat-laden working fluid from the at least one gas outlet heat exchanger and yield a cooled working fluid; and
at least one bottom loop heat exchanger fluidly coupled with the at least one bottom loop expander, the at least one outlet heat exchanger, and the at least one gas inlet heat exchanger, wherein the at least one bottom loop heat exchanger is disposed downstream from the at least one bottom loop expander and upstream of the at least one gas inlet heat exchanger and the at least one gas outlet heat exchanger, the at least one bottom loop heat exchanger being configured to receive the cooled working fluid from the at least one bottom loop expander and transfer the cooled working fluid to the at least one gas inlet heat exchanger.

16. The method of claim 15, wherein the working fluid is selected from ammonia, carbon dioxide, or a combination thereof.

17. The method of claim 16, wherein the working fluid is carbon dioxide.

18. The method of claim 17, wherein the working fluid is supercritical carbon dioxide.

19. The method of claim 16, wherein the working fluid is ammonia.

20. The method of claim 19, wherein the working fluid is supercritical ammonia.

21. The method of claim 15, wherein the at least one gas inlet heat exchanger comprises microchannels.

22. The method of claim 15, wherein the at least one gas inlet heat exchanger comprises one or more printed circuit heat exchanger cores.

23. The method of claim 15, wherein the at least one gas outlet heat exchanger comprises microchannels.

24. The method of claim 15, wherein the at least one gas outlet heat exchanger comprises one or more printed circuit heat exchanger cores.

25. The method of claim 15, wherein the bottom loop utilizes waste heat at the outlet side of the gas turbine in combination with the at least one gas inlet heat exchanger to yield a reduction in a temperature of the inlet gas provided to the inlet side of the gas turbine.

26. The method of claim 15, wherein the cooled working fluid from the at least one bottom loop heat exchanger is provided to the at least one gas inlet heat exchanger for use in a reduction of a temperature of the inlet gas provided to the inlet side of the gas turbine.

27. The method of claim 15, wherein the bottom loop is a heat engine configured to utilize transferred heat to condition the inlet gas and generate surplus power or energy.