Patent ID: 8065879
Filing Date: 2011-11-29
Classification: F01K,F25J,Y02E,Y02P

Abstract:
1. A process for the integration of a cryogenic air separation plant and an oxy-combustion power plant, comprising: producing a pressurized nitrogen stream and a pressurized oxygen stream within said cryogenic air separation plant; wherein said cryogenic separation plant has an air compressor outlet pressure of about 11 bar abs and produces oxygen at a pressure of approximately 1.8 bar abs; burning a fuel stream thereby generating a steam stream from a boiler feed water stream, wherein said stream is used for work expansion within said oxy-combustion power plant; heating said pressurized nitrogen stream and said pressurized oxygen stream with a compressed air stream that is extracted from the air compressor of said cryogenic air separation plant, thereby forming a heated pressurized nitrogen stream and a heated pressurized oxygen stream; burning a fuel stream with said heated pressurized oxygen stream to produce a flue gas stream, wherein said flue gas stream is at about atmospheric pressure; heating said heated pressurized nitrogen stream to form a hot pressurized nitrogen stream; work expanding said hot pressurized nitrogen stream to a lower pressure thereby forming a hot exhaust nitrogen stream and recovering energy; and heating said boiler feed water stream by indirect heat exchange with said hot exhaust nitrogen stream, wherein said pressurized nitrogen stream comprises a high pressure nitrogen stream and a medium pressure nitrogen stream, wherein both said high pressure nitrogen stream and said medium pressure nitrogen stream are produced within said cryogenic air separation plant, further comprising: heating said high pressure nitrogen stream, said medium pressure nitrogen stream and said pressurized oxygen stream with said compressed air stream thereby forming a heated high pressure nitrogen stream, a heated medium pressure nitrogen stream, and heated pressurized oxygen stream; burning a fuel stream with said heated pressurized oxygen stream to produce a flue gas stream; heating said heated high pressure nitrogen stream to form hot high pressure nitrogen stream; work expanding hot high pressure nitrogen stream to a lower pressure thereby forming a hot exhaust medium pressure nitrogen stream thereby recovering a first portion of energy; mixing said hot exhaust medium pressure nitrogen stream with said heated medium pressure nitrogen stream to form a warm combined medium pressure nitrogen stream; heating said warm combined medium pressure nitrogen stream to form a hot combined medium pressure nitrogen stream; work expanding said hot combined medium pressure nitrogen stream to form a hot exhaust combined nitrogen stream thereby recovering a second portion of energy; and heating said boiler feed water stream by indirect heat exchange with said hot exhaust combined nitrogen stream.