CONTROL OF REHEAT STEAM FOR ELECTRIC POWER PLANT BOILER

摘要

PROBLEM TO BE SOLVED: To provide a method for controlling reheat steam for an electric power plant boiler, which method makes it possible to maintain the reheat steam at a high temperature when the load is lowered and to improve the stability of the flame and the capability of detecting the flame. ;SOLUTION: A boiler is equipped with a boiler furnace 1, first and second burner steps 3, 4 provided on the furnace wall of the boiler furnace 1, wind box inlet dampers 5 for controlling the flow rate of combustion air supplied to the first and second burner steps 3, 4, a flue 6, a superheater 7 and a reheater 8 provided inside the flue 6, an exhaust gas-recirculating fan 9, and an air heater 10. When the load is commanded to lower by an amount corresponding to the lowering of the flow rate of fuel the amount of air or the amount of the mixture of air and exhaust gas with which the boiler furnace is charged from the second burner step at rest is transitionally increased. As a result, collection of heat in the furnace is suppressed and the reheat steam temperature is maintained at a required value.;COPYRIGHT: (C)1998,JPO