Combined cycle power plant with co2 capture plant

Abstract

A combined cycle power plant includes a CO2 capture system operatively integrated with a liquefied natural gas LNG regasification system, where cold energy from the regasification process is used for cooling processes within the CO2 capture system or processes associated with it. These cooling systems include systems for cooling lean or rich absorption solutions for the CO2 capture or the cooling of flue gas. The LNG regasification system is arranged in one or more heat exchange stages having and one or more cold storage units. The power plant with CO2 capture can be operated at improved overall efficiencies.

What is claimed is: 
     
         1 . A combined cycle power plant comprising a gas turbine (GT), a steam turbine (ST), a heat recovery steam generator (HRSG), a liquefied natural gas (LNG) regasification system, and a CO2 capture system arranged to process exhaust gases exhausted by the heat recovery steam generator (HRSG) wherein
 the liquefied natural gas regasification system comprises heat exchangers operatively connected with heat exchangers within the CO2 capture system,   wherein one or more heat exchangers arranged in a cascaded way, configured for the operation at temperatures of the natural gas form an LNG inlet temperature up to at least −10° C. and of which at least one heat exchanger is configured and arranged for heat exchange between the liquefied natural gas and a heat exchange medium, where that heat exchange medium has cryogenic temperatures or chilling temperatures at the output from that at least one heat exchanger.   
     
     
         2 . The combined cycle power plant according to  claim 1  wherein
 the CO2 capture system is a system arranged for a chilled ammonia process and the power plant comprises lines to direct the heat exchange medium from this regasification heat exchanger to one or more of the following refrigeration systems within the CO2 capture system 
 a cooler integrated in a cooling circuit of a flue gas direct contact cooler (DCC), 
 a water cooler prior to a flue gas water wash apparatus (WW), 
 a cooler for the cooling of CO2 rich absorption solution within the CO2 capture system. 
 
     
     
         3 . The combined cycle power plant according to  claim 1  wherein
 the CO2 capture system is a system arranged for an amine process for the removal of CO2 from flue gases and the liquefied natural gas regasification system comprises one or more heat exchangers arranged in a cascaded way, configured for the operation of the natural gas from an LNG inlet temperature up to at least 0° C. and of which at least one heat exchanger is configured and arranged for heat exchange between the liquefied natural gas and a heat exchange medium, where that heat exchange medium has cryogenic temperature or chilling temperatures at the output from that at least one heat exchanger. 
 
     
     
         4 . The combined cycle power plant according to  claim 3  wherein
 the power plant comprises lines to direct the heat exchange medium from this regasification heat exchanger to a system (LSC) for cooling a CO2 lean solution within the CO2 capture amine process system. 
 
     
     
         5 . The combined cycle power plant according to  claim 1  wherein
 the at least one heat exchanger, which is configured and arranged for heat exchange between the liquefied natural gas and a heat exchange medium that has a cryogenic temperature or a chilling temperature at the output from the heat exchanger, is operatively connected to a system for cooling the inlet air to the gas turbine (GT) of the combined cycle power plant. 
 
     
     
         6 . The combined cycle power plant according to  claim 5  wherein
 the one or more heat exchangers of the liquefied natural gas regasification system are additionally operatively connected to one or more of the following systems of the combined cycle power plant: 
 a system for flue gas cooling prior to its entry to the CO2 capture system, 
 a system for flue gas chilling prior to its entry to the CO2 capture system. 
 a cooling water system for the steam turbine condenser, 
 a system for the cooling of flue gas recirculated after the HRSG back to the gas turbine inlet, 
 a system for the chilling of flue gas recirculated after the HRSG back to the gas turbine inlet, 
 a system for cooling of CO2 extracted by the CO2 capture system. 
 a system for drying CO2 by means of chilling. 
 
     
     
         7 . The combined cycle power plant according to  claim 1  wherein
 the heat exchangers of the liquefied natural gas regasification system are arranged either in series or in parallel. 
 
     
     
         8 . The combined cycle power plant according to  claim 7  wherein
 each of the heat exchangers of the LNG regasification system are configured and arranged for heat exchange within a given temperature range, where each one of the heat exchangers can comprise one or more heat exchange apparatuses, which can be arranged either in series or in parallel to one another. 
 
     
     
         9 . The combined cycle power plant according to  claim 5  wherein
 the liquefied natural gas regasification system comprises one or more cold storage units for the storage of liquefied natural gas arranged in parallel to its heat exchangers. 
 
     
     
         10 . The combined cycle power plant according to  claim 1  wherein
 the system for liquefied natural gas regasification comprises a heat exchanger configured and arranged for the liquefaction of CO2 extracted by the CO2 capture system. 
 
     
     
         11 . The combined cycle power plant according to  claim 6  wherein
 a line leads from the system for drying and cooling CO2 to the heat exchanger for CO2 liquefaction and a line for liquefied CO2 leads from this heat exchanger to a transport facility (T) or pump. 
 
     
     
         12 . The combined cycle power plant according to  claim 1  wherein
 the liquefied natural gas regasification system comprises a heat exchanger configured and arranged for heat exchange between liquefied natural gas and a medium having cryogenic temperatures at the output of said heat exchanger and a line for said heat exchange medium that leads to an air separation unit, and a line leads from said air separation unit (ASU) back to said heat exchanger. 
 
     
     
         13 . The combined cycle power plant according to  claim 5  wherein
 the liquefied natural gas regasification system is additionally operatively connected to the cooling system for the steam turbine (ST) condenser.