Patent GB-475324-A (GB)
Title: Improved process and apparatus for the purification of gas and vapour
IPC: B01D45/14
Filed: 1937-04-07
Abstract: 475,324. Centrifugal gas-cleaners. ROTEX-ENTSTAUBUNGSANLAGEN GES., and ANDREAS, A. April 7, 1937, No. 9909. [Class 23] Gases or vapours are purified during their passage through a rotating cylindrical drum, and the impurities deposited by centrifugal action are removed during rotation of the drum by scrapers, aspirators, beaters, or the like. The upper end of the drum 15 is supported by arms 14 from the hollow shaft 11 which can be rotated through gearing from the motor 13, and the lower end of the drum is connected by arms 22, which act as fan blades, to the bush 23 on the trunnion 10. Labyrinth seals 16 are provided between the drum and the outer casing 10. The gas inlet pipe 18 opens tangentially into the chamber A which has a helical rib 10<11> to assist the correct movement of the gas. A similar chamber B has a tangential discharge pipe 19 connected to a fan 20 for withdrawal of the cleaned gas. In this form of apparatus the separated dust deposited on the drum wall is withdrawn by an exhauster 41 which consists of a number of pipes with transverse terminations 43<1>, 43<11>, 43<111> each having an aperture at its end for the entry of the dust. This exhauster 41 is supported by runners 27, 28 in the trunnions 25, 24 so that it can be moved axially in the drum by manual operation of the segment 42, while it is automatically reciprocated slowly in a radial motion by worm and eccentric gear 38, 37 from the motor 13. A tapper 59 is provided at the top of the drum and filter cloths 21 are stretched over the arms 14. The heavy dust deposited in the chamber A is discharged through an opening normally covered bv the cap 58, and the heavier dust in the drum is deposited at the lower end so that the dust in the pipes a, b, c of the exhauster is graded. Each pipe is connected to a separate cyclone separator 45 from which the discharge is taken by a fan 52 through a filter bag 50. An arrangement of flap valves enables each separator 45 to be isolated, or its clean gas discharge taken independently of the filter bag, to the inlet pipe 18 of the main separator. In the modification shown in Fig. 4 the rotary drum 70 has an horizontal axis. The gas flows from the inlet 72 past helical guide vanes 76 and leaves the drum by the chamber 73 with its tangential outlet to the fan 78, while the dust is deposited on the drum. The hollow core 79 inside the drum has a worm 80, and a slide 82 is fitted in an opening at the top of the core. This slide which is reciprocated by the mechanism 87, 86, 85, 84 has three vertical pipes 89 for the withdrawal of the dust which drops through the pipes to the worm 80 and is carried to the discharge outlet 92. The end of each pipe 89 has a pointed front 89<1>, Fig. 6, and a sharp round rear edge 89<11> ; a plate 91 closes the end except for a crescent shaped opening. In further modifications concentric drums are arranged with a gas flow passing through them in series, or in parallel. Weighted flaps are arranged to close openings in the drum walls when they are rotated at full speed, but the openings are open for discharge of dust when the speed drops. Chains and suspended weights are employed to loosen the deposited dust.