CONTROL METHOD AND DEVICE FOR PRESSURIZED FLUIDIZED BED BOILER-COMPOUND POWER GENERATION FACILITY

PURPOSE:To realize the operation suitable for cooling a boiler at the time when the fuel supply to the pressurized fluidized bed boiler is stopped by determining the amount of feed water in response to the retained heat of a furnace- fluidized bed, and controlling the amount of other processes of the pressurized fluidized bed boiler in accordance with the amount of the feed water. CONSTITUTION:In a pressurized fluidized bed boiler, at least one part of a heat transfer pipe 3 in which feed water flows, is in contact with a flowing material to perform heat-exchange. A steam turbine 11 and generator 12 are driven by the steam obtained from the heat transfer pipe 3. A gas turbine 8 supplies high-pressure air to the pressurized fluidized bed boiler. When the cause of boiler-trip is judged and the steam turbine 11 is found to be tripped, the main steam pressure is controlled by a turbine-bypass valve 17. When a boiler mechanical stoker is out of order, the main steam pressure is controlled by a steam turbine governor 10, because the steam turbine 11 and the steam turbine-generator 12 are continuing the operation. Thus, at the time of boiler- trip, the boiler is shifted to a usual boiler stopped state to reduce thermal stress.