Use of nitrogen from an air separation unit as gas turbine air compressor feed refrigerant to improve power output

摘要

The work produced by the gas turbine expander (40), is improved by cooling a nitrogen product (86), produced by a cryogenic air separation unit (80), to a subambient temperature and combining this subambient cooled, nitrogen product (92) with the feed air stream (10) prior to compression (20). The cooling can be produced by expanding (90) the nitrogen product (86) and/or saturating it with water (Fig 2;190). The present invention is particularly suited to a process in which at least a portion of the oxygen product (84) produced by the cryogenic air separation unit (80) is reacted with a carbonaceous feedstock (72) in a gasification unit (70) to produce the fuel gas. IMAGE