GB544612A - Improvement in processes of manufacturing agglomerates from a coal base utilised as the only binder - Google Patents

Abstract

544,612. Preparing and agglomerating fuel. SOC. FINANCIERE DE TRANSPORTS ET D'ENTREPRISES INDUSTRELLES (SOFINA) SOC. ANON. March 29, 1940, No. 5652. Convention date, April 1, 1939. [Classes 50 and 55 (i)] Coal used as the only binder in making fuel agglomerates form 15 to less than 100 per cent of the materials which are crushed to particles below ¢ mm. diameter, the well mixed materials being heated to from 2‹ to 3‹ C. below the temperature at which they become sticky prior to being briquetted under a pressure of between 400 and 800 kgs/cm<2>. From 4 to 7 per cent of an inert constituent such as coke crushed to between ¢ and 1 mm. may be added. As inert additions, non-bituminous coal, or ores also are referred to. The mixture is heated in a rotary retort externally heated at usual speed up to 300‹ C. and then more rapidly up to the agglomerating temperature which may be 450‹ C. at which temperature hydrocarbons are evolved and provide the atmosphere in which heating takes place. The materials now becoming plastic are passed down a short heat-insulated shoot to presses working at between 400 and 800 kgs/cm<2>. The constituent materials from bunkers 1 to 4 are proportioned on platforms 5, 6, dried, crushed and mixed, and fed from a hopper 10 into the rotary retort 11 heated by the circulation of hot gases from a furnace 22 in an annular space 13 enclosed by a casing 12. The retort is divided by a helicoidal channel 15 into low and higher temperature zones 16, 17 from the latter of which the softened material flows down a shoot 19 into briquette presses 18. The upper part 16 of the retort is open to the atmosphere. Recirculation of the heating gases takes place as described in Specification 488,852. Specifications 356,236 and 460,394 also are referred to.