GB1299334A - Industrial waste gas purification system - Google Patents

Abstract

1299334 Purifying waste gases K AOI 19 April 1971 [27 Feb 1970 10 Sept 1970] 22777/71 Heading F4J After contacting a heat exchanger CH in a flue 2 waste gases diverted by a damper 3 down a pipe 5 pass in turn through a porous wall 7 into an expansion chamber 9 containing a cooling coil 10, a blower 18, further expansion chambers 21 in a purifier C, a filter chamber 27 and the heat exchanger CH, finally being delivered by the flue 29 into a chimney 1. Caustic soda solution introduced by a pipe 8 into the end of pipe 5 absorbs SO 2 in the chamber 9 and collects in a reservoir 14 through which air or ozone is bubbled to oxidize sodium sulphites into sulphate. Water from a tank 31 is supplied to the coil 10, is used to cool the chamber 9 externally and is also supplied to a cooling jacket 30 around the purifier C. The latter is packed with glass wool 25 which receives condensed water carrying small solid particles from the condensation chambers 24 of the expansion chambers 21. The waste gases enter the initial chamber 22 of the purifier C tangentially so that larger solid particles are deposited therein. More SO 2 dissolves in this condensate to form sulphurous acid which collects in reservoir 42. In a modification (Fig. 2) the chamber 9 is omitted and before reaching the heat exchanger the waste gases pass through an endless belt filter to remove solid particles. Water or a caustic solution is sprayed into the initial chamber 22 of the purifier C to remove fluorine.