Method for the shutdown and restarting of combined power plant

摘要

In shutting down a combined power plant, a steam turbine is first shutdown while operation of a gas turbine at high load is being continued, and the steam generated in a waste heat recovery boiler is passed on to a condenser through a bypass system bypassing the steam turbine. The gas turbine is then shutdown when this condition prevails, and gland sections of the steam turbine receive a supply of gland sealing steam which has been heated by a heater to a temperature level close to that of the steam attained while the steam turbine is in operation, thereby to maintain the temperature of the metal of the steam turbine gland sections at a desired level during the time the steam and gas turbines are shutdown. In restarting the combined plant, the gas turbine is first started and then the steam turbine is started.