GB195783A - Improvements relating to the heating and supply of feed water in steam power plants - Google Patents

Abstract

195,783. Fothergill, H. Jan. 12, 1922. Feed-water, supplying and controlling. - Steam power plant comprises an evaporator for feed-water make-up, a feed-water heater which receives steam from the evaporator and feed-water from the condenser, an outlet on the heater for air and other non-condensible gases, and means for maintaining in the heater, or its drainage chamber, a pressure corresponding to the steam temperature. The condensate from condensers a, Fig. 1, is forced by pumps b through a pipe c to a feed-water heater d. Steam from the evaporators f is condensed in the heater d and the mixed supply of hot water is forced by the pump g through the pipes e to the boilers. A partial vacuum corresponding to the temperature is maintained in the vessel d by an injector h, whereby the non-condensible vapours are liberated. In a modification, the water from the heater drains into a de-aerating chamber connected by a valved pipe with the main condenser for maintaining the requisite vacuum. When the exhaust from auxiliary plant n, Fig. 3, is used for feed-water heating in a main heater l, the hot drainage water is led by a pipe from the evaporators f into this heater and the condensate is led therefrom into the heater d which receives the condensate from the main condensers a and the steam from the evaporators. The mixed feed-water drains into the de-aerator vessel m the vacuum in which is maintained by an injector h. In a modification of this apparatus, the evaporator heater, and de-aerating chamber are combined, the heat exchanging functions of the water supplied by the three pipes opening into this chamber being effected by direct contact. The auxiliary plant may exhaust into the coils of one of the evaporators instead of into a main heater.