Power generation system and method with partially recuperated flow path

• US 9,657,599 B2
• Filed: 02/26/2015
• Issued: 05/23/2017
• Est. Priority Date: 02/26/2014
• Status: Active Grant

• Current Assignee: Peregrine Turbine Technologies LLC
• Original Assignee: Peregrine Turbine Technologies LLC
• Inventors: Stapp, David Scott
• Primary Examiner(s): Nguyen, Hoang
• Application Number:
  US14/632,672
• Publication Number:
  US 20150240665A1
• Time in Patent Office: 817 Days
• Field of Search: 60772, 60 39181, 60 39183, 60650, 60655, 60651
• CPC Class Codes: F01K 11/02 the engines being turbines
• CPC Class Codes: F01K 13/02 Controlling, e.g. stopping or starting
• CPC Class Codes: F01K 19/04 in combination with cooling or heating
• CPC Class Codes: F01K 23/02 the engine cycles being thermally coupled
• CPC Class Codes: F01K 25/103 Carbon dioxide F01K25/065 takes precedence
• CPC Class Codes: F01K 3/18 having heaters having both steam accumulator and heater F01K3/14; steam heaters per se F22
• CPC Class Codes: F01K 7/16 the engines being only of turbine type the engines using steam of critical or overcritical pressure F01K7/32; the engines being of extraction or non-condensing type F01K7/34
• CPC Class Codes: F02C 1/007 combination of cycles
• CPC Class Codes: F02C 1/04 the working fluid being heated indirectly in a fluidised-bed combustor F02C3/205
• CPC Class Codes: F02C 1/10 Closed cycles
• CPC Class Codes: F02C 6/04 Gas-turbine plants providing heated or pressurised working fluid for other apparatus, e.g. without mechanical power output F02C6/18 takes precedence ; for a fluidised-bed combustor F02C3/205
• CPC Class Codes: F22B 3/08 at critical or supercritical pressure values
• CPC Class Codes: Y02E 20/14 Combined heat and power generation [CHP]

Abstract

The present disclosure relates to a power generation system and related methods that use supercritical fluids, whereby a portion of the supercritical fluid is recuperated.

Claims

1. A method for generating power in a system that includes a supercritical fluid cycle having a supercritical fluid flowing therethrough, an air-breathing cycle having air flowing therethrough that does not mix with the flow of the supercritical fluid, the method comprising:

directing air along the air-breathing cycle to flow through a plurality of heat exchangers;

compressing the supercritical fluid in a supercritical fluid compressor along the supercritical fluid cycle;

splitting the supercritical fluid discharged from the supercritical fluid compressor into first and second discharge streams of compressed supercritical fluid, such that the first discharge stream of compressed supercritical fluid flows through a recuperating heat exchanger;

mixing the supercritical fluid discharged from the recuperating heat exchanger with the second discharge stream of compressed supercritical fluid;

directing a mixture of compressed supercritical fluid through one of the plurality of heat exchangers arranged and into an inlet of a supercritical fluid turbine, such that heat from the air along the air-breathing cycle is transferred to the mixture of compressed supercritical fluid;

splitting the supercritical fluid discharged from the supercritical fluid turbine into a first and second discharge streams of expanded supercritical fluid such that the first discharge stream of expanded supercritical fluid flows through the recuperating heat exchanger so as to heat the first discharge stream of compressed supercritical fluid;

mixing the expanded supercritical fluid discharged from the recuperating heat exchanger with the second discharge stream of expanded supercritical fluid; and

directing a mixture of expanded supercritical fluid toward the inlet of the supercritical compressor,

wherein heat from the mixture of expanded supercritical fluid is transferred to the air of the air-breathing cycle, thereby cooling the mixture of expanded supercritical fluid to approximately its critical point.

2. The method of claim 1 wherein the third directing step includes directing a mixture of expanded supercritical fluid through another one of the plurality of heat exchangers and into to the inlet of the supercritical compressor.

3. The method of claim 2, wherein the plurality of heat exchangers includes a first heat exchanger, a second heat exchanger, a third heat exchanger, and a fourth heat exchanger, wherein the air flows in a direction from the first heat exchanger to the second, third and fourth heat exchangers in sequence.

4. The method of claim 3, wherein the second directing step includes directing the mixture of compressed supercritical fluid through the third heat exchanger arranged to feed into an inlet of the supercritical fluid turbine.

5. The method of claim 4, prior to the first mixing, directing the second discharge stream of compressed supercritical fluid through the fourth heat exchanger.

6. The method of claim 3, wherein the third directing step includes directing the mixture of expanded supercritical fluid through the first heat exchanger.

7. The method of claim 4, prior to the second mixing, directing the second discharge stream of expanded supercritical fluid through the second heat exchanger.

8. The method of claim 1, wherein the plurality of heat exchangers includes a first heat exchanger, a second heat exchanger, and a third heat exchanger, wherein the air flows in a direction from the first heat exchanger to the second and third heat exchangers in sequence.

9. The method of claim 8, wherein the second directing step includes directing the mixture of compressed supercritical fluid through the second heat exchanger arranged to feed into an inlet of the supercritical fluid turbine.

10. The method of claim 9, prior to the first mixing, directing the second discharge stream of compressed supercritical fluid through the third heat exchanger.

11. The method of claim 8, wherein the third directing step includes directing the mixture of expanded supercritical fluid through the first heat exchanger.

12. The method of claim 8, prior to the second mixing, directing the second discharge stream of expanded supercritical fluid through the first heat exchanger.

13. The method of claim 1, wherein the first directing includes:

compressing the flow of air in an air cycle compressor; and

expanding the air through an air cycle turbine.

14. The method of claim 13, wherein the plurality of heat exchangers includes a first heat exchanger, a second heat exchanger, and a third heat exchanger, wherein the air flows in a direction from the first heat exchanger to the second and third heat exchangers in sequence, wherein the expanding occurs prior to the air flowing through the third exchanger.

15. The method of claim 1, wherein the first directing comprises combusting the air before the air flows through the heat exchangers.

16. The method of claim 13, further comprising exhausting the flow of air.

17. The method of claim 16, wherein air flow is exhausted from one of the heat exchangers.

18. The method of claim 16, wherein air flow is exhausted from the air cycle turbine.

19. The method of claim 1, further comprising cooling the supercritical fluid via one or more coolers.

20. A system configured to generate power, comprising:

a supercritical fluid cycle including a supercritical fluid compressor configured to receive and compress a supercritical fluid, a supercritical fluid turbine configured to receive and expand the supercritical fluid, and a recuperating heat exchanger configured to receive discharge streams from the supercritical fluid compressor and the supercritical fluid turbine;

an air breathing cycle configured to heat air flowing along the air breathing cycle; and

a plurality of heat exchangers arranged so that supercritical fluid from the supercritical fluid cycle and air from the an air breathing cycle passes therethrough but does not intermix,

wherein the system is configured to;

1) split the supercritical fluid discharged from the supercritical fluid compressor into first and second discharge streams of compressed supercritical fluid, such that a) the first discharge stream of compressed supercritical fluid flows through the recuperating heat exchanger, and b) the second discharge stream of compressed supercritical fluid flows through one set of the plurality of heat exchangers; and

2) split the supercritical fluid discharged from the supercritical fluid turbine into a first and second discharge streams of expanded supercritical fluid such that a) the first discharge stream of expanded supercritical fluid flows through the recuperating heat exchanger, and b) the second discharge stream of expanded supercritical fluid flows through a different set of the plurality of heat exchangers, wherein heat from the first discharge stream of expanded supercritical fluid is transferred to the first discharge stream of the compressed supercritical fluid in the recuperating heat exchanger.

21. The system of claim 20, wherein the plurality of heat exchangers includes a first heat exchanger, a second heat exchanger, and a third heat exchanger, wherein the air flows in a direction from the first heat exchanger to the second, and third heat exchangers in sequence.

22. The system of claim 21, wherein the system is configured so that the second discharge stream of compressed supercritical fluid flows through the third heat exchanger, which in turn, directs the stream to the second heat exchanger arranged to feed into an inlet of the supercritical fluid turbine.

23. The system of claim 22, wherein the system in configured to A) mix the discharge from the third heat exchanger with the discharge of compressed supercritical fluid from the recuperating heat exchanger, and B) direct the mixture of compressed supercritical fluid through the second heat exchanger into the inlet of the supercritical fluid turbine.

24. The system of claim 22, wherein the system is configured so that the second discharge stream of expanded supercritical fluid flows through the first heat exchanger, which in turn, directs the stream toward the inlet of the supercritical fluid compressor.

25. The system of claim 24, wherein the system is configured to A) mix the discharge from first heat exchanger with the discharge of expanded supercritical fluid from the recuperating heat exchanger, and B) direct the mixture of expanded supercritical fluid toward the inlet of the supercritical fluid compressor.

26. The system of claim 20, wherein the plurality of heat exchangers includes a first heat exchanger, a second heat exchanger, a third heat exchanger, and a fourth heat exchanger, wherein the air flows in a direction from the first heat exchanger to the second, third and fourth heat exchangers in sequence.

27. The system of claim 26, wherein the system is configured so that the second discharge stream of compressed supercritical fluid flows through the fourth heat exchanger, which in turn, directs the stream the third heat exchanger.

28. The system of claim 27, wherein the system in configured to A) mix the discharge from fourth heat exchanger with the discharge of compressed supercritical fluid from the recuperating heat exchanger, and B) direct the mixture of compressed supercritical fluid through the third heat exchanger into an inlet of the supercritical fluid turbine.

29. The system of claim 28, wherein the system is configured so that the second discharge stream of expanded supercritical fluid flows through the second heat exchanger, which in turn, directs the stream to the first heat exchanger.

30. The system of claim 29, wherein the system is configured to A) mix the discharge from second heat exchanger with the discharge of expanded supercritical fluid from the recuperating heat exchanger, and B) direct the mixture of expanded supercritical fluid through first heat exchanger and toward the inlet of the supercritical fluid compressor.

31. The system of claim 20, further comprising:

a first valve configured to split the supercritical fluid discharged from the supercritical fluid compressor into the first and second discharge streams of compressed supercritical fluid; and

a second valve configured to split the supercritical fluid discharged from the supercritical fluid turbine into the first and second discharge streams of expanded supercritical fluid.

32. The system of claim 20, further comprising a cooler that reduces the temperature of the supercritical fluid prior to its entry into the supercritical fluid compressor.

33. The system of claim 20, wherein the air breathing cycle includes at least one air cycle compressor, at least one air cycle turbine, and at least one combustor.

34. The system of claim 20, wherein the air breathing cycle includes at least one induced draft fan, at least one forced draft fan, and at least one combustor.

35. The system of claim 33, wherein the induced draft fan includes a first power source and the forced draft fan includes a second power source.

36. A system configured to generate power, comprising:

a supercritical fluid cycle including a supercritical fluid compressor configured to receive and compress a supercritical fluid, a supercritical fluid turbine configured to receive and expand the supercritical fluid, and a recuperating heat exchanger configured to receive discharge streams from the supercritical fluid compressor and the supercritical fluid turbine;

an air breathing cycle configured to heat air flowing along the air breathing cycle; and

a plurality of heat exchangers arranged so that supercritical fluid from the supercritical fluid cycle and air from the an air breathing cycle passes therethrough but does not intermix, wherein a first heat exchanger of the plurality of heat exchangers is arranged to feed into an inlet of the supercritical fluid turbine, and a second heat exchanger of the plurality of heat exchangers is arranged to feed into an inlet of the supercritical fluid compressor, wherein the first heat exchanger has a first heat capacity rate and the second heat exchanger has a second heat capacity rate that is substantially different than the first heat capacity rate;

wherein the system is configured to

1) split the supercritical fluid discharged from the supercritical fluid compressor into first and second discharge streams of compressed supercritical fluid, such that a) the first discharge stream of compressed supercritical fluid flows through the recuperating heat exchanger, and b) the second discharge stream of compressed supercritical fluid flows through the first heat exchanger of the plurality of heat exchangers, and

2) split the supercritical fluid discharged from the supercritical fluid turbine into a first and second discharge streams of expanded supercritical fluid such that a) the first discharge stream of expanded supercritical fluid flows through the recuperating heat exchanger, and b) the second discharge stream of expanded supercritical fluid flows through the second heat exchanger of the plurality of heat exchangers.

37. The system of claim 36, wherein the first and second heat exchangers are configured to receive respective flows at temperature ranges that are substantially different with respect to each other.

38. The system of claim 36, further comprising one or more valves.

39. The system of claim 38, where the one or more valves is A) a first valve configured to split the supercritical fluid discharged from the supercritical fluid compressor into the first and second discharge streams of compressed supercritical fluid, and B) a second valve configured to split the supercritical fluid discharged from the supercritical fluid turbine into the first and second discharge streams of expanded supercritical fluid.

40. The system of claim 36, further comprising a cooler that reduces the temperature of the supercritical fluid prior to its entry into the supercritical fluid compressor.

41. The system of claim 36, wherein the air breathing cycle includes at least one air cycle compressor, at least one air cycle turbine, and at least one combustor.

42. The system of claim 36, wherein the air breathing cycle includes at least one induced draft fan, at least one forced draft fan, and at least one combustor.

43. The system of claim 42, wherein the induced draft fan includes a first power source and the forced draft fan includes a second power source.