Patent ID: 6915661
Filing Date: 2005-07-12
Classification: F25J

Abstract:
1. A process for separating air in a system comprising a gas turbine, including a compressor, a combustor and an expander, said expander being coupled to the compressor, a natural gas conversion unit, a natural gas liquefaction unit and an air separation unit comprising the steps of: a) compressing air in a compressor, sending a first part of the air to a combustor and a second part of the air to an air separation unit; b) separating at least the second part of the air in the air separation unit to form at least an oxygen enriched gas and an nitrogen enriched gas; c) sending a first stream of natural gas from a source of natural gas to the natural gas conversion unit and at least part of the oxygen enriched gas to the natural gas conversion unit; d) compressing at least part of the nitrogen enriched gas and sending at least part of the compressed nitrogen enriched gas upstream of the expander; and, e) feeding a second stream of natural gas from the source of natural gas to the natural gas liquefaction unit, wherein the work produced by the expander is used to operate a cycle compressor of a refrigeration cycle of the natural gas liquefaction unit.