| 摘要 |
PURPOSE:To join waste gas ducts from complex gas turbine into one, by providing dampers to check reverse flow and to prevent abnormal rise in pressure to a waste gas duct which leads combustion gas to a stack. CONSTITUTION:A waste gas damper 26 and an abnormal rise in pressure preventing damper 27 which works as a check valve are installed in a waste gas duct 25 which extends from a waste heat recovery boiler 20 to a stack 24. The pressure in the waste gas duct 25 rises abnormally by the compressed air which is produced by empty running of a gas turbine, if the waste gas damper 26 at the outlet of a waste heat recovery boiler is quickly closed when the gas turbine is tripped. But the duct 25 is enabled to be prevented from abnormal rising in pressure by the abnormal rise in pressure preventing damper 27, by adjusting the timing to close the waste gas damper 26 at the outlet of a waste heat recovery boiler 20 slow. On the other hand, when one gas turbine is operated and another one is stopped, combustion gas from the gas turbine in operation can be prevented from reversely flowing into the one in a halt state by installing the damper 27, which works as a reverse flow check valve, in the waste gas duct 25. |
