GB839669A

GB839669A - Improvements in the generation of steam power

Info

Publication number: GB839669A
Application number: GB10924/58A
Authority: GB
Original assignee: Foster Wheeler Ltd
Current assignee: Amec Foster Wheeler Holdings Ltd
Priority date: 1957-04-08
Filing date: 1958-04-03
Publication date: 1960-06-29

Abstract

839,669. Power-generating systems. FOSTER WHEELER Ltd. April 3, 1958 [April 8, 1957], No. 10924/58. Class 122 (3). [Also in Group XIII] A steam power plant comprises a once through boiler 20 operating at supercritical pressure, an independently fired superheaterreheater chamber 39 and a three-stage turbine 43 driving an electric generator 44. There are two operating circuits. In the first water is drawn from a steam and water vessel 13 by a pump 15 and delivered to the tubing 19 of the boiler 20 at supercritical pressure. In the boiler it is heated to above critical temperature and leaves through a line 22 to a turbine 26 driving the pump 15 and a turbine 27 on the shaft of the main turbine 43. Superheated steam exhausts from the turbines 26, 27 into the vessel 13 wherein it heats feed water to generate saturated steam forming the working fluid of the second circuit. In the second circuit the steam from the vessel 13 passes through a superheater 37 in the chamber 39 to the high-pressure stage 42 of the turbine 43. The exhaust is reheated at 38 and flows through the subsequent turbine stages 46, 49 to a condenser 50. Condensate is withdrawn by a pump 52 and returned to the vessel 13 through a series of bled steam heaters 53 ... 55, 63 ... 65. During full load operation the burners 21, 40 of the boiler 20 and superheater-reheater chamber 39 respectively are fired so as to provide for equal absorption of heat by the elements 19 and 37, 38 and the whole of the steam exhausting from the turbines 26, 27 flows into the vessel 13. At less than full load a valve 33 in a by-pass 32 opens to allow some of the superheated steam to bypass the vessel 13 and flow directly to the superheater 37 in admixture with the saturated steam from the vessel 13. Under these conditions the heat required from the burners 40 is much reduced and their firing rate is decreased whilst that of the burners 21 is kept at a high level. Specifications 761,617 and 805,257 are referred to.