Process for releasing ammonia bound in coal water

A process for releasing ammonia bound in coal water containing the ammonia in the form of salts of strong acids in an ammonia-hydrogen sulfide scrubbing process of a combined pre-desulfurization and ammonia removal plant having a hydrogen scrubber and an ammonia scrubber, the scrubbing process being of the type wherein raw coke oven gas containing ammonia and hydrogen sulfide is passed into the hydrogen scrubber, scrubbed with ammonical water received in the hydrogen scrubber from the ammonia scrubber to form a prepurified gas, and in which the prepurified gas is then passed into the ammonia scrubber and scrubbed with water to form the ammonical water to be used in the hydrogen scrubber, the improvement wherein the water passed in the ammonia scrubber is the coal water, and further comprising the steps of then passing the coal water into the hydrogen sulfide scrubber, scrubbing the prepurified gas in the ammonia scrubber with an aqueous alkali solution after the prepurified gas is scrubbed with the coal water to form an alkali solution enriched with acid components, and passing the enriched alkali solution into the hydrogen sulfide scrubber to liberate the ammonia bound in the coal water.