Nuclear fired boiler feed preheater-degasser - with reduced radiation hazard

摘要

The device consists of a vessel placed directly beneath the main condenser. The upper section of the vessel contains degassing baffles, over which the condensate passes mixing at the same time with a portion of hot fluid direct from the turbine, which heats it to above the saturated vapour pressure of the vessel, causes some flash evaporation and thus degasses it. The lower portion of the vessel has for boiler feed holding capacity sufficient to ensure that the dwell time is long enough to allow the decay of any radioactive contamination and thus make feed pump maintenance problems less hazardous. Some of the maintenance problems encountered in nuclear power stations with direct recycle of the working fluid, can be overcome by using this design of feed degasser preheater.