US 11,732,644 B2
Organic Rankine Cycle for combined-cycle power plant
Shimin Deng, Oakville (CA)
Assigned to Mitsubishi Power Americas, Inc., Lake Mary, FL (US); and Mitsubishi Power, Ltd., Yokohama (JP)
Appl. No. 17/252,177
Filed by Mitsubishi Power Americas, Inc., Lake Mary, FL (US); and Mitsubishi Power, Ltd., Yokohama (JP)
PCT Filed Jun. 27, 2018, PCT No. PCT/US2018/039688
§ 371(c)(1), (2) Date Dec. 14, 2020,
PCT Pub. No. WO2020/005220, PCT Pub. Date Jan. 2, 2020.
Prior Publication US 2021/0254547 A1, Aug. 19, 2021
Int. Cl. F02C 6/04 (2006.01); F01K 23/10 (2006.01); F02C 7/18 (2006.01); F02C 7/22 (2006.01); F02C 7/224 (2006.01)
CPC F02C 6/04 (2013.01) [F01K 23/10 (2013.01); F02C 7/18 (2013.01); F02C 7/22 (2013.01); F02C 7/224 (2013.01); F05D 2220/32 (2013.01); F05D 2220/722 (2013.01); F05D 2240/36 (2013.01); F05D 2260/232 (2013.01)] 8 Claims
OG exemplary drawing
 
7. A method of operating a gas turbine combined-cycle power plant, the method comprising:
circulating an organic fluid through a closed loop Organic Rankine Cycle (ORC) system using a fluid pump;
pumping the organic fluid through a first fluid line connected to an outlet of the fluid pump;
heating the organic fluid received from the first fluid line in a heater with a first external heat source;
flowing the heated organic fluid from the heater through a second fluid line extending from the heater to a first fluid juncture;
splitting the heated organic fluid at the first fluid juncture into a first portion and a second portion;
flowing the first portion of the heated organic fluid through a third fluid line extending from the first fluid juncture to a heat sink input side of a recuperator;
flowing the second portion of the heated organic fluid through a fourth fluid line extending from the first fluid juncture to a heat sink input side of a second heat exchanger;
flowing the first portion of the heated organic fluid from the heat sink input side of the recuperator to a heat sink output side of the recuperator to further heat the first portion of the heated organic fluid,
flowing the first portion of the heated organic fluid through a fifth fluid line extending from the heat sink output side of the recuperator to a second fluid juncture
flowing the second portion of the heated organic fluid from the heat sink input side of the second heat exchanger to a heat sink output side of the second heat exchanger to further heat the second portion of the heated organic fluid,
flowing the second portion of the heated organic fluid through a sixth fluid line extending from the heat sink output side of the second heat exchanger to the second fluid juncture;
flowing the first and second portions of the heated organic fluid through a seventh fluid line extending from the second fluid juncture to a heat sink input side of a first heat exchanger, the first and second portions of the heated organic fluid forming a combined organic fluid;
flowing the combined organic fluid from the heat sink input side of the first heat exchanger to a heat sink output side of the first heat exchanger;
delivering a compressed air stream from a compressor of the gas turbine combined-cycle power plant to a heat source input side of the first heat exchanger via a first compressed air line;
cooling the compressed air stream by flowing the compressed air stream from the heat source input side of the first heat exchanger to a heat source output side of the first heat exchanger, the combined organic fluid absorbing heat from the compressed air stream resulting in a heated combined organic fluid at the heat sink output side of the first heat exchanger and a cooled compressed air stream at the heat source output side of the first heat exchanger;
flowing the cooled compressed air stream from the heat source output side of the first heat exchanger into a second compressed air line that transports the cooled compressed air;
flowing a portion of the cooled compressed air from the second compressed air line into a third compressed air line that extends from the second compressed air line to a heat source input side of the second heat exchanger to further cool the portion of the cooled compressed air by heating the second portion of the pumped organic fluid flowing through the second heat exchanger;
flowing the heated combined organic fluid from the heat sink output side of the first heat exchanger into an eighth fluid line that extends to an input end of an ORC turbine;
expanding the heated combined organic fluid working fluid through the ORC turbine resulting in expanded organic fluid at an outlet end of the ORC turbine;
generating electrical power with the ORC turbine;
flowing the expanded organic fluid from the outlet end of the ORC turbine into a ninth fluid line extending from the outlet end of the ORC turbine to a heat source input side of the recuperator;
flowing the expanded organic fluid from a heat source output side of the recuperator into a tenth fluid line that extends to an organic fluid input side of a condenser;
condensing the expanded organic fluid entering the organic fluid input side of the condenser as a gas and leaving an organic fluid output side of the condenser as a liquid organic fluid by using liquefied natural gas as a heat sink fluid; and
returning the liquid organic fluid to the fluid pump by flowing the liquid organic fluid through an eleventh fluid line extending from the organic fluid output side of the condenser to an inlet of the fluid pump.