GB472276A - Improvements in or relating to the distillation or heat treatment of solid carbonaceous materials and apparatus therefor - Google Patents

Abstract

472,276. Rotary retorts for heating solid carbonaceous materials. BRITISH COAL DISTILLATION, Ltd., HARDY, R. D., MACHEN, C., ARAM, E. H. G. March 20, 1936, No. 8382. [Classes 51 (ii) and 55 (i)] In the distillation or heat treatment of coal or other solid carbonaceous materials in a rotary retort comprising an outer shell 8 and a, number of tubes 9, the material is fed through the retort in the space around the tubes and is heated directly by the passage of hot gases through this space, and indirectly by the passage of gases through the tubes. Coal, for example, is fed from a bunker 1 to a hopper 3, and is dried in its passage through a dryer 4 heated by return gas from the retort, a main 5a leading this cooled gas for use in a combustion chamber 24. The preheated coal enters by a feed valve 7, the retort in which it is agitated by lifters 11 during rotation, and through which it passes around the tubes and through ports 12 in tube supporting plates 9a, being discharged by lifters 28a and shoot 28. The heating gases from the combustion chamber 24 are attemperated by the cooled gas from main 5a, and pass in countercurrent to the coal, passing both through the tubes and around them in amounts controlled by a circulating fan 34 for the gas for indirect heating, and a fan 19 for the gas for direct heating. The fan 34 withdraws the heating gas through a duct 33 and annular receiving chamber 14 from the tubes 9, and supplies it through pipe 35 to the jacket 5 of the coal dryer, a part of the gas being byepassed through a pipe 36 into contact with the coal, after which it escapes to the atmosphere through a pipe 37. The distillates and heating gases in contact with the charge pass by an outlet 16 to a cyclone 17, condenser 18, fan 19, scrubber 20, and gas holder 21, from which a pipe 22 leads to a burner 23 in the combustion chamber. To prevent leakage, glands 31 are supplied through pipes 32 with gas under slight pressure. Valves 19a, 25 and 36a, in conjunction with fans 19 and 34, adjust the proportion of internal to external heating gas. Specification 401,767 is referred to.