GB1344374A - Thermal pyrolysis of fibrous materials - Google Patents

Abstract

1344374 Pyrolysis of carbonized materials V P SOSEDOV A T KAVEROV V G MOROZOV A I AMAN N I TIMOSHIN G S SOROVTSEV N M CHERNENKO V G JUDIN I V SEROV B N BORISOV and L I GRACHEV 3 Aug 1971 36395/71 Heading C1A Thermal pyrolysis of partially or totally carbonized fibrous material is effected by moving the material through a heating zone, matter volatilizing from the material as the temperature of the latter is being raised not being permitted to come into contact with material of higher temperature, being forcibly evacuated in the direction opposite to that of material movement. Preferably, the material is moved through the heating zone at a speed greater than 6 m. per min., especially between 6À5 and 10 m. per min., in the presence of a purifying and/or protective gas stream, flowing countercurrent to the direction of movement of the material, which is heated to 500 to 3000‹ C., especially to 1100‹ C. at a rate of 30,000‹ to 85,000‹ C. per min. In apparatus as shown, carbonaceous fibrous material 1 in the form of a fabric, ribbon, strand, filament or yarn is wound off roll 2 and enters central channel 3 of a cylindrical electric furnace 4. The channel, which may be graphitelined, extends normally to the axis of the furnace. The material is heated to the required temperature while passing through the heating chamber 6 of channel 3, and volatile matter formed thereby is forcibly evacuated in the opposite direction by the action of hydraulic seal 7 and suction pipe 8, optionally with the assistance of a stream of purifying or protective gas supplied through nipples 9. The seal 7 moves also to cool the material, which then passes to drying chamber 13 prior to wind-up on driven take-up roll 15. The furnace comprises a cylindrical metal housing 20 having a water-cooled jacket 21, and containing coaxial inner and outer screens 23 and 22, made of graphite or other refractory material separated by heat insulation material 25, e.g. carbon black. A tubular heater 26 is disposed axially in the heating chamber 6, and above the heater and below the uppermost screen is the central channel 3. Current is supplied to each end of heater 26 by water-cooled cap ring 27, contact between each ring and the end of the heater being realized through an intermediary wedge 28. This contact is sealed by end cap 29, and one end cap has an inspection hole 30 which permits measurement of the temperature of heater 26, e.g. by means of an optical pyrometer. Arrows B and C indicate the direction of supply of cooling water to caps 27 and 29 and housing 20.