GB316174A - Process of treating coke oven gases and like gases - Google Patents

Abstract

316,174. Union Chimique Belge Soc. Anon. July 24, 1928, [Convention date]. Purifying processes; materials for purifying.- In a process of treating coke oven gases or the like with an ammoniacal solution which is then caused to react with calcium sulphate to produce ammonium sulphate, as described in, Specification 262,320, the cold gases issuing from the apparatus for condensation of tar and ammoniacal liquor from the crude gas, are subjected to scrubbing with a. solution rendered alkaline with anhydrous ammonia. The hot coke oven gas from pipe 1 is cooled in a condenser 2 and passes to a scrubber 6 where it is treated with ammoniacal solution fed from a receptacle 16. This solution absorbs the acid impurities and flows into a mixer 19 in which it is treated with calcium sulphate to give a solution of ammonium sulphate and calcium salts which are separated from the insoluble materials in a filter 21 and treated as in Specification 262,320. The gas and volatile ammonia pass by a pipe 7 to a scrubber 8 fed with cold water or ammonium sulphate and the purified gas enters a cooler 10, through which extends a pipe 22 carrying cold anhydrous ammonia, and is deprived of the hydrocarbons such as benzol which flow out through pipe 32, the completely purified gas escaping through pipe 11. The ammonia from pipe 22 is fed by pipe 23 to the receptacle 16 where it meets the liquid from the scrubber 8 which is delivered through a pipe 15. Ammoniacal liquor from the cooler 2 is fed by a pump 26 and pipe 27 to a still 28 from which the volatiles pass through a condenser 29 and pipe 30 to the ammonia pipe 23; these acid gases supply a further source of ammonium carbonate suitable for sulphatation by the gypsum.