High temperature oxygen production with steam and power generation

摘要

Oxygen is separated from air by means of a high temperature ion transport membrane which is integrated with a gas turbine system for energy recovery from the membrane nonpermeate stream. Air is compressed, heated in a first heating step, and passed through the feed side of a mixed conductor membrane zone to produce a high purity oxygen product on the permeate side of the membrane zone. Nonpermeate gas from the membrane zone is heated in a second heating step and passed through a hot gas turbine for power recovery. Water is added to the nonpermeate gas prior to the hot gas turbine to increase mass flow to the turbine and thus balance the mass flows of the air feed compressor and the expansion turbine. The operating temperatures of the membrane zone and the expansion turbine are independently maintained by controlling the rate of heat addition in the first and second heating steps and by controlling the rate of water addition, whereby the membrane zone and expansion turbine are thermally delinked for maximum oxygen recovery efficiency.