Patent ID: 7980052

Claim:
An industrial gas turbine engine comprising: a main gas turbine engine connected to an electric generator to produce electric power, the main gas turbine engine including a main compressor and a main combustor and a main turbine; a smaller gas turbine engine compressing a cooling fluid for the turbine in the main gas turbine engine, the smaller gas turbine engine including a small compressor and a small combustor and a small turbine; an air separator to produce a nitrogen gas; a low pressure nitrogen line to connect the nitrogen gas from the air separator to an inlet of the small compressor; a high pressure nitrogen line to connect an outlet of the small compressor to a cooling circuit within hot parts of the main turbine; a compressed air line to connect the main compressor to the small combustor to supply compressed air for combustion; the main turbine including hot parts formed from a high temperature resistant material but poor oxidation resistance selected from a group of Niobium, Molybdenum, Tungsten, Rhenium, Tantalum, and oxidation dispersed strengthened alloys; and, the main combustor operating in a stoichiometric or fuel rich combustion to produce a hot gas stream for the main turbine that is low in oxygen.