GB729129A - Improvements in or relating to method and apparatus for purifying solid carbonaceousmaterial selected from the class consisting of coke and ahthracite coal - Google Patents

Abstract

In a process of purifying coke or anthracite by treatment with chlorine at a high temperature the material to be purified is passed successively and continuously in successive quantities through a pre-treatment zone and a chlorination zone in which the material is heated to drive off volatile hydrogen containing material and is treated with chlorine respectively, the gases from each zone being separately withdrawn and the communication of gas from either zone to the other being prevented. The pre-treatment zone is preferably heated to at least 1,000 DEG C. and the chlorination zone to at least 1,400 DEG C., the holding time of the material in each treatment may be in the region of 6-10 hours. Apparatus described for carrying out the process comprises a cylindrical furnace 10 having a refractory lining 12 and divided into three zones, a pretreating zone 18, an intermediate zone 30 and a chlorination <PICT:0729129/III/1> zone 20, by sliding dampers 31 and 32. Coke or anthracite to be treated is charged into the uppermost zone 18 where it is heated by vertically separated sets of carbon electrodes 21 and 22 to the desired pretreatment temperature, any gases liberated escaping through an outlet 28. By operation of the dampers 31 and 32, pretreated material from the zone 18 passes to the intermediate zone 30 and material in the zone 30 is charged to the chlorination zone 20, the operation being so conducted that chlorine from the zone 20 does not enter the zone 18. The zone 30 has a gas outlet 44. In the zone 20 chlorine is admitted through an inlet 25 and gases containing unreacted chlorine and volatilized chlorides of iron, silicon and titanium pass out through an outlet 26 while the temperature of the material under treatment is raised by further electrical heating, spaced set of carbon electrodes 23 and 24 being provided. The purified coke or anthracite is withdrawn through an opening in the chamber 15. The dampers 31 and 32 may be operated manually, electrically or as shown by connections 37 and 38 to the pistons of fluid-pressure operated cylinders 41 and 42. In a modification the material may be fed from the pretreatment zone to the chlorination zone by means of a screw-feeder disposed in an intermediate zone and having openings in communication with the two zones at opposite ends of the screw. Specifications 715,478 and 716,718 are referred to.