GB1321735A - Purification of gases or vapours - Google Patents

Abstract

1321735 Electrostatic separators ETAB AEROMIX 19 May 1971 [20 May 1970] 15883/71 Heading B2J Gas or vapour containing solid particles and/or liquid particles and/or gaseous constituents (e.g. SO 2 , HF) as impurities is purified by passing the gas or vapour through an ionisation zone and thereafter passing the gas or vapour through at least one zone containing electrically uncharged liquid droplets whereby, due to induction and dipole attraction, the electrically charged impurities combine with the droplets which are then separated from the gas or vapour. As shown (Fig. 1), a separator comprises ionisation wires 2 at an inlet zone 1, nozzles 5-8 to form a cloud of water droplets 13, a droplet separator 15 filled with Raschig rings, copper chips, coke or wood wool, a fan 4 and an outlet pipe 16 leading to a settling tank 17 from where the purified water is recycled by a pump 18. In a modification (Fig. 2, not shown) vanes (32) are provided to produce a rotational movement of gas through the separator for droplet separation purposes, the water is sprayed by atomizer wheels (23, 24) and the outlet gas is monitored photoelectrically (37, 38) to automatically vary the number and/or size of drops to maintain a constant outlet purity. In a further modification, (Figs. 3 and 4, not shown) separation of the droplets is achieved by a combination of centrifugal forces and electrostatic forces using an earthed wall. Several separators may be arranged in parallel (Figs. 5 and 6, not shown).