GB628321A - Fluid heating - Google Patents

Abstract

628,321. Steam superheaters; air and gas heaters &c BABCOCK & WILCOX CO. June 21, 1945, No. 15845. Convention date, July 4, 1944. [Classes 64(i) and 123(iii)] [Also in Group XXX] Fluid heating apparatus, e.g. a steam superheater or an air or fuel gas heater, comprises a pair of fluid heaters A, B in each of which fluent refractory heat transfer material is passed successively through an upper chamber 12 and a lower chamber 13 in which it is respectively heated and cooled by contact with heating and cooling fluids passing through those chambers, the fluid heated in the lower chamber of one heater A taking part in combustion to produce the heating gases supplied to the upper chamber of the second heater B. Air or fuel gas may be heated in the first heater A and supplied through the pipe 44 to burners 29 in the combustion chamber of the heater B, which may be used to superheat steam or heat air or fuel gas. A series of more than two heaters may be used, each except the last heating fuel or air for combustion in the next heater. Alternatively, both fuel and air may be heated in two such heaters for combustion in a third. In each heater the two chambers 12, 13 are connected by a throat 14 surrounded by an annular chamber 43 into which the heated fluid from the lower chamber flows through a ring of slots 40. An annular combustion chamber 25 surrounds the upper chamber 12. Discharge of the refractory material from the lower-chamber without substantial leakage of fluid is controlled by vertically reciprocating valves (see Group XXX). The material is returned by an elevator 88 to a pipe 16 discharging into the upper chamber 12. Dust mixed with this material can be entrained by hot gases flowing from the chamber 12 through the pipe 20 leading to a cyclone separator 98. A separate hot gas outlet 17 is also provided.