Method of treating an acid gas stream and an apparatus therefor

摘要

The present invention provides a method of treating an acid gas stream (820) comprising HS and CO to provide an aqueous ammonium sulphate stream (190) and an apparatus (1) therefor, the method comprising at least the steps of : (a) passing an acid gas stream (820) comprising HS and CO to an incinerator (850) to oxidise HS to SO to provide an incinerator flue gas stream (860) comprising SO and CO; (b) passing the incinerator flue gas stream (860) to a sulphuric acid unit (900) to produce HSO from SO in the flue gas stream (860) to provide an aqueous sulphuric acid stream (910) and a sulphuric acid unit off-gas stream (920) comprising CO; and (c) passing at least a part of the aqueous sulphuric acid stream (910) to an ammonia scrubber (150) which is provided with a first off-gas stream (120) which comprises NH, HS and CO to separate NH to provide a scrubber off-gas stream (180) comprising HS and CO and an aqueous ammonium sulphate stream (190).