GB346874A

GB346874A - Improvements in or relating to furnaces

Info

Publication number: GB346874A
Application number: GB274630A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1930-01-27
Filing date: 1930-01-27
Publication date: 1931-04-23

Abstract

346,874. Ore-reducing furnaces. STANSFIELD, A., McGill University, Mon. treal, Canada. Jan. 27, 1930, No. 2746. [Classes 51 (i) and 51 (ii).] A furnace for reducing ores comprises a rectangular stack 20 divided by vertical partitions 22 into compartments each fitted with a series of oppositely inclined floors 24 down which the charge travels in succession, there being provided apertures 220 .. 224 in the partitions 22 and connecting flues 210 in the side walls 21 of the stack to constitute a continuous zig-zag channel for the upward passage of heating gases. The charge is fed downwardly over the floors 24 by water or air-cooled reciprocating rakes 26, Fig. 8, having bevelled cross-bars 260, outlets 265 to the heating-gas channel being provided when air is used as the cooling medium. The lowermost floor 241 delivers either to an electric furnace 1, Figs. 1 and 2, the hot gases from which enter the stack, or to a cooler 4 comprising a number of vertical tubes 3, Fig. 3, around which air passes in a tortuous path to a chamber 6 having delivery apertures 61. Gaseous fuel is supplied from a manifold 8 through ports 80, and additional fuel, which may be gas, oil, or pulverized coal, may be supplied to the ascending gases through openings 211 in the side walls of the stack. The cooled charge is delivered by screws 32 to a receiver 5 which also collects any treated material passing from the floor 241 through the overflow opening 33. As shown in Fig. 5, some of the intermediate floors 24 may be muffle-heated, the covers 7 providing chambers for the production of gas from excess fuel mixed with the charge ; the gas thus produced is taken off through outlets 71 and fed, after purification, either to the manifold 8 or to the inlets 211. The uppermost floor 242, Fig. 1, is more steeply inclined and constitutes a hopper in which the charge is preheated before passing to the next floor. Valves 25 may be provided to control the downward passage of the charge.