Gas turbine combined plant

摘要

In a gas turbine combined plant (10) comprising a gas turbine section (20) and a steam turbine section (30) a cooling water passage is provided for guiding a part of water from a waste-heat recovery boiler (34) into an air cooler (24) as a cooling medium for high-temperature air that passes through the air cooler. The water heated due to the heat exchange is returned to the waste-heat recovery boiler (34). A bypass passage is provided for guiding water at a lower temperature than that of water at a primary side of the cooling water passage into the air cooler (24) and a switching valve (48,49) is provided for selectively switching between the primary side of the cooling water passage and the bypass passage.