GB123739A - Improvements relating to Furnace Retorts. - Google Patents

Abstract

123,739. Smith, C. H. Feb. 18, 1918, [Convention date]. Retori furnaces; charging and discharging; casings and walls.-In a combined furnace and retort for the treatment of coal, the retort is formed at its lower part with an in. ternal longitudinal rib, and the charge is mixed and conveyed by blades on two parallel rotating shafts, so spaced that their blades overlap. The retort is of inverted heart-shaped section as shown in Fig. 4, and is built up of hollow tiles 4, 5, 6, arranged to form flues 4<a>, 5<a>, 6<a>, running the length of the retort. Burner nozzles 39 project into the open ends of the flues, and the products of combustion are withdrawn through a downcast flue 44, the combustion flues being connected at this end of the furnace by openings in the partition walls. The tiles 4, 5, 6 are preferably made of carborundum, or a mixture containing this material. Surrounding the combustion flues is a layer of fire-brick 12 which serves to store heat, and around this is a heat-insulating layer 13 of a diatomaceous earth brick known as " sigur " brick. The whole is enclosed within a metal casing made in two parts meeting in an horizontal plane about midway of the height of the structure, and between this casing and the brickwork in the upper part a layer 21 of asbestos is interposed to allow for expansion. The end walls are similarly lined with brick. The shafts 7, 8 are supported in open ended annular bearings 24, 25, of which the latter are mounted in removable covers sufficiently large to allow the removal of the shafts from the retort. The linings for the bearings are made of an alloy of copper, aluminium, and iron commercially known as " Ampco " metal. The shafts are hollow and may be made in a number of sections connected by spigot and socket joints. and locked together by the shafts of the blades. These latter are inclined to their plane of rotation at an angle which may vary from 35 degrees at the charging end to 45 degrees at the discharging end of the retort. Each blade g<a>, Fig. 12, is cast on its shaft 9<b>, which fits into a socket in the rotating shaft, and is secured in position by a nut, The material is fed into the retort by a screw conveyer, and after treatment passes down a divided shoot 57 to a rotary discharging drum 58. The material is broken up and forced into the pockets of the drum by rotary arms 64. Gaseous products are led off from the retort through pipes 46, 47 and passed to an hydraulic main 50, which is supported on rollers to allow of free expansion. Clearing devices are provided in connexion with the elbows 51, 52, 53. Specifications 101,539, [Class 55 (i), Coking &c.J, 106,084. and 111,285, [Class 55 (i). Coking &c.] , are referred to.