Combined open cycle system for thermal energy conversion

• US 6,715,294 B2
• Filed: 01/23/2002
• Issued: 04/06/2004
• Est. Priority Date: 01/24/2001
• Status: Expired due to Term

• Current Assignee: DRS Naval Power Systems, Inc. (Leonardo S.p.A.)
• Original Assignee: DRS Power Technology, Inc. (Leonardo S.p.A.)
• Inventors: Anderson, Rodger O.
• Primary Examiner(s): Look, Edward K.
• Assistant Examiner(s): Belena, John F.
• Application Number:
  US10/055,802
• Publication Number:
  US 20020116930A1
• Time in Patent Office: 804 Days
• Field of Search: 60/395, 602/27, 607/72, 60/391.81, 60/391.82, 60/394.61, 60/395.2, 606/413, 606/415, 606/55, 606/68, 607/36, 607/75, 607/84, 415/139, 415/148, 415/159, 415/160, 310/10, 310/11
• US Class Current: 60/772
• CPC Class Codes: F01K 23/10 with exhaust fluid of one cycle heating the fluid in another cycle F01K17/025 takes precedence
• CPC Class Codes: F02C 1/007 combination of cycles
• CPC Class Codes: F02C 1/06 using reheated exhaust gas F02C1/08 takes precedence
• CPC Class Codes: F02C 6/18 using the waste heat of gas-turbine plants outside the plants themselves, e.g. gas-turbine power heat plants using waste heat as source of energy for refrigeration plants F25B27/02; using the waste heat of a gasturbine for steam generation or in a steam cycle see F01K23/10
• CPC Class Codes: Y02E 20/16 Combined cycle power plant [CCPP], or combined cycle gas turbine [CCGT]

Abstract

A dual-fluid heat engine having a gas turbine and an open cycle steam turbine. The gas turbine has a compressor for compressing a first working fluid, the compressor having a compressor outlet. The gas turbine has a combustion chamber in fluid communication with the compressor outlet. The turbine portion of the gas turbine has an inlet in fluid communication with the combustion chamber for performing work by expansion of the first working fluid, and a gas turbine exhaust. A heat recovery exchanger is coupled to the gas turbine exhaust having a heat recovery inlet and an outlet for heating a second working fluid, water. The water is converted into steam in the heat recovery exchanger. A pump increases the pressure of the water prior to entrance in the heat recovery exchanger. An atmospheric exhaust expansion steam turbine extracts energy from the heated second working fluid to drive an electrical generator. An exhaust chimney takes the gas turbine exhaust and the steam turbine exhaust and rejects it into the atmosphere.

Claims

1. A combined cycle system comprising:

an open cycle system using a fuel to create power and expending an exhaust with a waste heat;

a heat exchange fluid;

a heat recovery exchanger for transferring heat from the exhaust with waste heat to the heat exchange fluid;

a second open cycle system using the heat exchange fluid to create power and expending the heat exchange fluid; and

an exhaust system that combines the exhaust from the first open cycle and the heat exchange fluid from the second open cycle and conveying to the atmosphere.

2. A combined cycle system of claim 1 wherein the heat exchange fluid is water in a fluid and gaseous state.

3. A combined cycle system of claim 2 further comprising a pump for moving and pressurizing the water to the heat recovery exchanger.

4. A combined cycle system of claim 3 further comprising a purifier for purifying the water.

5. A combined cycle system of claim 3 wherein the open cycle system is a gas turbine.

6. A combined cycle system comprising:

an open cycle system using a fuel to create power and expending an exhaust with a waste heat;

water as a heat exchange fluid;

a heat recovery exchanger for transferring heat from the exhaust with waste heat to the water to convert from a liquid state to a gaseous state, steam;

an open cycle system steam turbine using the steam to create power and expending the steam; and

an exhaust system that combines the exhaust from the gas turbine and the steam expended from the open cycle steam turbine and conveying to the atmosphere.

7. A combined cycle system of claim 6 wherein the heat recovery exchanger is a once-through exchanger.

8. A combined cycle system of claim 6 wherein the heat recovery exchanger is a drum boiler.

9. A combined cycle system of claim 8 wherein the open cycle system is a gas turbine.

10. A combined cycle system of claim 9 further comprising a pump for moving and pressurizing the water to the drum boiler heat recovery exchanger and a purifier for purifying the water.

11. A combined cycle system comprising:

an open cycle system gas turbine using a fuel to create power and expending an exhaust with a waste heat;

water as a heat exchange fluid;

a heat recovery exchanger for transferring heat from the exhaust with waste heat to the water to convert from a liquid state to a gaseous state, steam;

a pump for moving and pressurizing the water to the heat recovery exchanger;

an open cycle system steam turbine using the steam to create power and expending the steam; and

an exhaust system that combines the exhaust from the gas turbine with the steam expended from the open cycle steam turbine and conveying to the atmosphere.

12. A combined cycle system of claim 11 wherein the heat recovery exchanger is a drum boiler.

13. A combined cycle system of claim 12, wherein the open cycle system steam turbine creates in a range of between 30 to 45 percent of the power produced by the gas turbine.

14. A combined cycle system of claim 13 wherein the open cycle system steam turbine creates in a range of between 34 to 40 percent of the power produced by the gas turbine.

15. A dual-fluid heat engine comprising:

a compressor for compressing a first working fluid, the compressor having

a compressor outlet;

a combustion chamber in fluid communication with the compressor outlet;

a gas turbine having an inlet in fluid communication with the combustion

chamber for performing work by expansion of the first working fluid, and a

gas turbine exhaust;

a heat recovery exchanger coupled to the gas turbine exhaust having a heat recovery inlet and an outlet for heating a second working fluid;

a pump to increase the pressure of the second working fluid prior to entrance into the heat recovery exchanger;

an atmospheric exhaust expansion steam turbine, the steam turbine extracts energy from the heated working fluid to drive an electrical generator; and

an exhaust chimney that combines the gas turbine exhaust with the steam turbine exhaust and rejects the exhaust from the gas turbine and the steam turbine into the atmosphere.

16. A dual-fluid thermal energy conversion system comprising:

an air compression mechanism for compressing air;

a combustion mechanism in fluid communication with the air compression mechanism, wherein a fuel is mixed with the air, ignited and burned to produce a first working fluid;

a first expansion mechanism in fluid communication with the combustion mechanism for conversion of a portion of the thermal energy from the first working fluid into mechanical energy which is employed to drive a first machine;

a heat exchanging mechanism in fluid communication with the first expansion means, the heat exchanging mechanism transferring a portion of the ‘

thermal energy from the first working fluid to a second working fluid;

a first exhaust mechanism in fluid communication with the heat exchanging mechanism to receive and convey the first working fluid to the atmosphere;

a second expansion mechanism in fluid communication with the heat exchanger mechanism receiving the second working fluid and converting thermal energy from the second working fluid into mechanical energy to drive a second machine;

a second exhaust mechanism in fluid communication with the second expansion mechanism to receive and convey the second working fluid to the atmosphere; and

the first exhaust mechanism and the second exhaust mechanism are interconnected so as to mix the first working fluid with the second working fluid prior to exhausting the mixture to the atmosphere.

17. A method of improving performance of a gas turbine power plant comprising the steps of:

providing an open cycle gas turbine system power plant using a fuel to generate power and expending an exhaust gas;

pressurizing a quantity of water;

extracting heat from the exhaust gas and heating the water to convert to steam;

rotating a steam turbine with the steam to generate more power; and

combining the exhaust gas from the gas turbine with the steam expending from the steam turbine and conveying to the atmosphere.