TODAY’S PATENT – BOILERS
The BOILERS was invented by John W. E. Campbell (Maidenhead) on the 14th of June 1983 , bearing patent number US4387577A.
The present invention relates to power plant forced-flow boilers operative with water letdown.
The present inventor in the following invention observes that the mentioned manner of recovering letdown water heat involves a degradation of heat without the gain of a corresponding conservation of latent heat in the overall cycle such as is achieved by feed heating that exploits the condensation of partly expanded steam bled for the purpose from one or more stages of the prime mover, such as turbines, driven by the steam. Here in a power plant forced-flow boiler operative with water letdown, the letdown water is arranged to deliver heat to partly expanded steam passing through a steam re heater connected between two stages of the prime mover. It is known to recover much of the heat in the letdown water leaving the drum by passing the letdown water through a heat exchange cooled by boiler feed water on its way from the condenser to the boiler economizer.