GB111413A - Improvements in Furnaces for Generating Heat. - Google Patents

Abstract

111,413. Thomas, W., and Mainwaring, A. E. March 29, 1917. Gas-producer furnaces.-A combined coking, gasifying, and primary-combustion chamber is constructed with a lower part of greater width for the body of coked and ignited fuel and an upper part of less width for gasifying fresh fuel, the gas being exhausted from the upper part so that poorer hot gases are drawn from the body of incandescent coke through the fresh fuel. The gas is delivered to a combustion chamber to which air is supplied, and some of it is delivered also to the fuel chamber. In a modification the whole of the gas is delivered into the fuel chamber on its way to the combustion chamber. In the form of furnace shown in Figs. 3, 5, and 6, fuel is supplied to the narrow upper coking section 2<a> from a hopper 9 by a screw or other feeder 10 driven through friction gearing which allows the feed to stop when the coking chamber is full. After coking, the fuel descends by gravity to the wider portion 2 and is burnt on a grate formed of inclined sections 4, the bars of which are rocked by eccentrics. Clinkers &c. are removed by a revolving breaker 4a. The gases evolved in the coking section are withdrawn by a fan 31, mixed with air supplied through a valve b, and returned, some to the fuel chamber through ports 41, and the remainder to the secondary combustion chamber 15 through a series of flues 38 in the side walls of the furnace. Air for combustion of the gas is forced by a fan 18 through a heater in the smoke stack of the boiler 16, and delivered in part through flues 26 opening into the gas flues 38, and the remainder through ports 29 in the dividing wall between the fuel and secondary combustion chambers. The air-heater consists of sinuous pipes 21 arranged in parallel between upper and lower headers. The products of combustion from the lower part of the furnace enter the secondarycombustion chamber through ports 14, 14a. In another form of furnace shown in Figs. 8 and 9, the gases evolved in the coking section, 52a are withdrawn through a port 57 and returned to the lower part of the furnace through flues 58 by jets of superheated steam. The gases pass into the secondary combustion chamber 66 through ports 60, and are burnt with air supplied through a transverse flue 56 and ports f. Additional supplies of air, heated in, flues 67, 70 are delivered through ports m, n. The grate consists of bars 4<c> arranged step-wise, and a broad clinker plate or table 4<d>. Water for cooling the bars is supplied through a pipe d.