Dual-pressure steam injection partial-regeneration-cycle gas turbine system

摘要

In the partial-regeneration cycle gas turbine system wherein part of the air compressed by a compressor 2 is extracted before a combustor 3, mixed with steam, and after the mixed gas is superheated by exhaust heat of a turbine, and the mixed gas is injected into the combustor, high-pressure steam is used as a fluid for driving a first mixer 22 that compresses extracted air, to increase the ratio of extracted air to steam, and then this mixed gas of extracted air and steam is further mixed with low-pressure steam from a low-pressure exhaust heat boiler, in a second mixer, and the mixture of gas is superheated in a superheater 6 by exhaust heat of the turbine, and injected into the combustor. Thus, the pressure of the driving steam can be raised, an exergy loss in an exhaust heat recovery portion can be reduced, and the efficiency of power generation can be increased without reducing the flow of generated steam.