GB472215A - Process of burning clay, clay shales and like argillaceous materials - Google Patents

Abstract

472,215. Rotary furnaces for burning clay &c. METALLGES. AKT.-GES. Jan. 6, 1937, No. 436. Convention date, Oct. 13, 1936. [Class 51 (ii)] In the burning of clay, clay shale, or the like in a rotary furnace 1 to produce a refractory structural material, the heating is effected by burners 16 distributed around and along the furnace and by the combustion of solid fuel contained in or admixed with the charge material, the necessary supplementary combustion air being introduced through the burners 16 and/or through separate spaced nozzles of similar design. In the form shown, the burners 16 are supplied with gas from a distributer 11 through pipes 15 and with air in excess from a distributer 10 through pipes 17, the air being preferably preheated in cross pipes 18 which communicate with the burners through a header 19 and pipes 20. The pipes 18 serve, particularly when the charge material has a high carbonaceous content, as cooling devices for keeping down the temperature in the first zone of the furnace, e.g. to between 500 and 700‹ C. The temperature in the succeeding main combustion zone is maintained at a figure between 600 and 1000‹ C. according to the character of the charge material, while, if desired, a final cooling zone may be provided in which the temperature of the material is reduced to about 150‹ C. When the original charge material has a low carbonaceous content, solid fuel, e.g. pulverized coal, is supplied through inlets in the furnace shell located at some distance from the charging device 3.