GB761282A - Shaft kiln - Google Patents

Abstract

761,282. Shaft furnaces. DE ROLL SOC. ANON., L. May 28, 1954 [May 28, 1953], No. 15931/54. Class 51 (2). In a shaft furnace for burning cement, lime or dolomite, or for sintering or reducing ores, even and easily controllable heating of the charge material fed by hoppers 3 and 4 is obtained by disposing above the shaft 1 a gas or oil-fired combustion chamber 5, from which hot gases pass into the top of the shaft through ports 9 in the narrow arch forming the bottom wall of the combustion chamber and through ports 10 in a peripheral duct 11 extending in and round the oral wall of the shaft and connected to the combustion chamber by ports 12. Additional ports 9a provide preheating gases immediately below the hoppers 3 and 4. Cooling air or gas is supplied at the foot of the shaft by a blower 19 and the air or gas taken off through peripheral ports 14 in the shaft may be used as combustion air in the chamber 5 or as reducing gas in the hottest zone of the furnace, respectively. A modification, Figs. 5-8 (not shown), has the combustion chamber formed as a peripheral ring in and round the top of the oval-shaped shaft, with hot gas ports extending inwardly and downwardly of the shaft wall and downwardly through a bridge on the major axis of the furnace and between the charging hoppers. Waste gases leave the shaft, either through the feed hoppers or through a chimney (not shown) between the hoppers and the surrounding wall.