GB115087A - Improvements relating to Methods of and Furnaces or Apparatus for Conducting High Temperature Reactions. - Google Patents

Abstract

115,087. Testrup, N., and Techno-Chemical Laboratories, Ltd. April 25, 1917. Roasting - furnaces. - High. temperature reactions are conducted by feeding a layer of the substance or material to be treated past a source of heat, a chamber or cavity confining an area of the substance being closed against heat diffusion by the relationship maintained between the perimeter of the chamber and the surface of the substance. With the apparatus shown, a layer of the material, of greater thickness and width than will be treated throughout, is fed to a travel-conveyer c and carried under a furnace fitted with a highlyheated membrane or slab b<1>, beneath which the walls of the furnace project so as to form a reaction chamber and to sweep aside a portion of the material, which thus forms a seal. At the discharge end, the wall of the furnace is continued as a downwardly-sloping bridge or cover k, beneath which the conveyer also slopes downward, and at the rear of this the top portion of the layer, which alone has been sufficiently treated, is removed by a slice f<2> and falls into a sump h, white the remainder falls on an inclined screen g. Above the slice is a breaking-roller g<1>. The material which fails to pass through the screen gravitates into the sump h, and that which passes through it is returned to the feed end by a screw i. Above the slab b' is a combustion chamber with burners at each side, the air supply to the burners being heated by the waste gases in a chamber d<1>. The slab is preferably thickened at its edges, so that less heat is transmitted to the portions of the material adjacent to the walls of the furnace, and the walls may be shaped as shown to reduce the area in contact with the material. and confine it to the cooler portions of the wall. Gases may be supplied to the reaction chamber by the pipe m.