GB679095A - Method of and apparatus for effecting thermal processes with finely granular or pulverulent carbonaceous substances with the production of active carbon - Google Patents

Abstract

The parent process which consists in bringing about or controlling thermal reactions between gases and solids suspended therein by passing the suspension through a mass of refractory bodies which introduce heat into or abstract heat from the reaction space, is modified in that activated carbon and combustible gases are produced, the starting material, consisting of pulverulent, carbonaceous matter such as anthracite, low temperature or peat coke, brown coal dust, sawdust or comminuted shells, being partially gasified and activated in contact with the heat carrier which is heated to a temperature at or above the gasification temperature preferably to 700-1300 DEG C. The apparatus consists of a vertical shaft furnace 1 divided into three sections by constrictions 7 and 8. A mass <PICT:0679095/III/1> of refractory bodies moves continuously down the shaft, being extracted by a wheel 13 and elevated to a feed hopper 12 for recirculation. In the top section 2 the bodies are heated to 700-1300 DEG C by combustion gases from a burner 15 and pass through the throat 7 to the gasifying space 3. The carbonaceous dust which may be impregnated with metallic salts or sulphuric or phosphoric acids to modify the properties of the active carbon produced, is introduced into zone 3 through a line 33 and swept up through the mass of heat carrier bodies by a flow of preheated steam from the lowermost zone 4. About 30-80 per cent of the carbon is gasified and the remainder activated by the steam, the combustible gases produced and the carbon discharging through ports into a separator 24, the carbon being collected at 25 and the gas passing forward to purifying plant 26, 27 and 30.