METHOD FOR REMOVING AMMONIA IN COKE OVEN GAS BY ABSORBING AND PRODUCTION OF AMMONIUM SULFATE OR LIQUID AMMONIA

摘要

PURPOSE:To increase the absorptivity and G/L ratio in the conditions for absorption of ammonia and to reduce the corrosion of an apparatus by dividing an ammonia absorber into an upper and lower sections, by supplying washing liq. having high concn. of acid from the upper section and by spraying washing liq. having lower concn. of acid from the lower section. CONSTITUTION:In the lower section 1b, the absorbing liq. having comparatively low concn. of acid (pH=8) is sprayed and circulated to be countercurrently brought into contact with the ammonia gas in a raw coke oven gas. In the upper section 1a, plural trays are equipped and the absorbing liq. having high concn. of acid (pH=6) is supplied to allow the ammonia gas not absorbed in the lower section 1b to be absorbed and removed. A part of the absorbing liq. in the upper section 1a is overflowed to the lower section 1b. When ammonium sulfate is produced, sulfuric acid S is used as acid and ammonium sulfate soln. A is taken out. When ammonia is produced, ammonium phosphate soln. P is used as acid and the ammonia is recovered from the obtd. ammonium phosphate soln. B.