Thermodynamic cycles with supercritical CO.sub.2 cycle topping

• US 3,971,211 A
• Filed: 04/02/1974
• Issued: 07/27/1976
• Est. Priority Date: 04/02/1974
• Status: Expired due to Term

• Current Assignee: Mcdonnell Douglas Corporation (The Boeing Co.)
• Original Assignee: Mcdonnell Douglas Corporation (The Boeing Co.)
• Inventors: Waters, William M., Wethe, Jay D.
• Primary Examiner(s): Ostrager, Allen M.
• Application Number:
  US05/457,286
• Time in Patent Office: 847 Days
• Field of Search: 60/39.18 A, 60/39.18 B, 60/39.18 C, 60/39.18 R, 60/655, 60/647, 60/650, 60/651, 60/671, 60/682
• US Class Current: 60/39.181
• CPC Class Codes: F01K 23/06 combustion heat from one cycle heating the fluid in another cycle
• CPC Class Codes: F01K 25/103 Carbon dioxide F01K25/065 takes precedence
• CPC Class Codes: F01K 7/32 the engines using steam of critical or overcritical pressure
• CPC Class Codes: F02C 3/28 using a separate gas producer for gasifying the fuel before combustion

Abstract

Gas turbine, steam turbine and/or process steam systems are combined with supercritical carbon dioxide cycle engines to produce major improvements in net plant efficiency by using the heat inputs and outputs of the supercritical CO₂ cycle to supply or remove heat in advantageous ways to the gas turbine, steam turbine and/or process steam systems.

Claims

1. A heat engine comprising:

a circulating system containing CO₂ above its critical pressure, a CO₂ pump having an inlet and an outlet, said CO₂ pump raising the pressure of the CO₂ from a first supercritical pressure to a second supercritical pressure, a primary heat exchanger having a CO₂ inlet and outlet, said primary heat exchanger heating the CO₂ when it is at a pressure above said first supercritical pressure, a secondary heat exchanger having a CO₂ inlet and outlet, said secondary heat exchanger cooling the CO₂ when it is at said first supercritical pressure, a recuperator having high and low pressure sides, said recuperator being for transferring heat from the CO₂ at the first pressure to CO₂ at a higher supercritical pressure, and a turbine having an inlet and an outlet, said turbine expanding the CO₂ extracting work therefrom and exhausting at said first supercritical pressure; and

a gas turbine system having a compressor for increasing the pressure of air fed thereto, a combustor having an input to receive the compressed air from the compressor and an input to receive fuel, the compressed air and fuel being burned in said combustor to form hot combustion products, means for placing said hot combustion products in heat transfer relationship with the CO₂ in said primary heat exchanger to heat the CO₂, and a turbine connected to receive the combustion products from said primary heat exchanger, said turbine expanding and cooling said combustion products to extract work therefrom to drive said compressor, said CO₂ turbine being connected at its high pressure side to said primary heat exchanger and on its low pressure side to said recuperator, said recuperator being connected to pass a portion of the low pressure CO₂ to said secondary heat exchanger, said secondary heat exchanger cooling the CO₂ and conducting it to said CO₂ pump which pressurizes said CO₂ and conducts it to the high pressure side of said recuperator, said system including a CO₂ compressor connected to receive a portion of the low pressure CO₂ from said recuperator and to pressurize it;

said recuperator high pressure side including a junction for receipt of the CO₂ pressurized by said CO₂ compressor, the heat engine further including;

a primary boiler connected to receive the combustion products from said turbine, said primary boiler transferring heat from the combustion products to pressurized water to generate steam therefrom;

a steam turbine connected to receive the steam from said primary boiler and to expand it to extract work therefrom;

a condenser connected to receive the steam once the work has been extracted therefrom, said condenser converting the work extracted steam to water;

a water pump connected to said condenser to pressurize the water therefrom;

feed water heater means connected to said water pump and being in heat transfer relationship to said secondary heat exchanger which extracts heat from the CO₂ by heating the pressurized water; and

means for conducting the pressurized water from said feed water heater means to said primary boiler for heating into steam.

2. The heat engine defined in claim 1 including:

a supplementary combustor for burning fuel and air supplied thereto, said supplementary combustor being connected to supply the combustion products thereof to said primary boiler to supply additional heat thereto;

a secondary boiler connected to receive the combustion products from said primary boiler and pressurized water from said feed water heater means, said secondary boiler transferring heat from the combustion products to the pressurized water to generate steam therefrom; and

a regenerator connected to receive the combustion products from said secondary boiler, said regenerator also being connected between said compressor and said combustor whereby said regenerator transfers heat from the combustion products to the compressed air.

3. The heat engine defined in claim 1 including:

a coal gasifier connected to receive compressed air from said compressor to pressurize the process of conversion of coal into gaseous fuel; and

means to conduct the gaseous fuel to said combustor for burning.