GB490264A - Improvements in or relating to the low temperature distillation of fuels - Google Patents

Abstract

490,264. Low-temperature carbonization. SOC. CHIMIQUE DE LA GRANDE PAROISSE AZOTE ET PRODUITS CHIMIQUES. June 24, 1937, Nos. 17632 and 17633. Convention dates, June 30, 1936 and May 29, 1937. [Class 55 (i)] In the low-temperature distillation of fuels, such as shale, which descend through a vertical retort whilst being traversed by horizontal currents of gas at different temperatures in a preheating and distillation zone respectively, heat is supplied to the distillation zone solely by distillation gases evolved therefrom repeatedly traversing the zone with intervening reheating in an external heater and mingling with the freshly distilled gas. The distillation zone of the retort C is provided on opposite sides with louvre slats P defining one side of admission and evacuation chambers 2, 3a ... 3c respectively to which the heating medium is supplied and withdrawn through pipes 1 and 4 connected to a heater 6 disposed in a furnace F attached to a firebox G. Part of the furnace gases after passing through a heat exchanger E are supplied to a similar admission chamber 10 on one side of the preheating zone of the retort and are withdrawn by a fan V, and the remainder of the furnace gases are re-cycled to the furnace by a fan V<2> to control the temperature of the gases surrounding the heater 6. Distillation is initiated by heating the distillation zone externally, the fan V<1> in the closed circuit being started ; the external heating is discontinued after distillation commences. The coke may be discharged into a pan of water at the base of the retort. In a modification of the invention, the supply and evacuation chambers for the heating medium are concentrically arranged and separated by an annular chamber containing the fuel retained between two cylindrical perforated containers.