| 摘要 |
The present invention provides a method and apparatus for treating a first off-gas stream (60) in a gasification process to provide an ammonium- rich stream (170) and an apparatus therefore, the method comprising at least the steps of: (a) providing a first off-gas stream (60) comprising HCN, NH3, H2S, CO2 and optionally one or both of COS and CS2 by separating a slurry bleed stream (720) comprising particulate solids, HCN, NH3, H2S, CO2 and optionally one or both of COS and CS2 in a sour slurry stripper (50) to provide the first off-gas stream (60) and a stripped slurry stream (70) comprising particulate solids; (b) passing the first off-gas stream (60) to a hydrolysis zone (100) operating at a pressure in the range of 1.5 to 10 bars to hydrolyse the HCN and any COS and CS2 to provide a second off-gas stream (110) comprising NH3, H2S and CO2; and (c) scrubbing the second off-gas stream (110) with an aqueous acidic stream (180) in an ammonia scrubber (150) to provide a third off-gas stream (160) comprising H2S and CO2 and an ammonium- rich aqueous stream (170). |
