GB751553A - Improvements in the operation of super critical pressure forced flow once-through steam generators - Google Patents

Abstract

751,553. Starting-up supercritical-pressure steam boilers. SULZER FRERES, SOC. ANON. June 28, 1954 [Aug. 31, 1953], No. 18844/54. Class 123(2). In a steam power plant comprising a forcedflow once-through steam boiler 5, working at supercritical pressure, and high, medium and low pressure turbines 7, 11, 15 with interposed steam reheaters 9, 13 located, respectively, within and outside the radiant zone of the boiler furnace 3, the reheater 9 is cooled during starting-up of the boiler by steam generated in the boiler and supplied thereto by a pipe 29 extending between the supply and exhaust pipes 6, 8 of the turbine 1. The exhaust starting-up steam is then led from. the supply pipe 10 of the turbine 11 through a pipe 25 to the feedwater tank 1 which is connected to the condenser 16 of the plant by a pipe 26 fitted with a pressure-relief valve 27. In a modification, steam or water from an external source is used as coolant ; in this case the pipe 8 is fitted with a steam or water supply pipe and the pipe 10 with an exhaust or drain pipe, and the pipe 25 extending to the feedwater tank 1 leads from the pipe 6. In each arrangement the turbines are fitted with inlet and outlet valves 18, 21, 23 and 19, 22, respectively.