| 摘要 |
H2S is removed from gas obtd. in black liquor evapn. by feeding the gas (3) contg. H2S and CO2 to a tower (1) for countercurrent multistage contact (6,7,8) with circulating carbonate contg. alkaline solns. (13, 14, 15) whose pH is adjusted during contact to 9-12 by addn. of hydroxide (26-28) so that H2S is absorbed to a total sulphide concn. above 0.3 moles/l in the outgoing soln (18) in contact with incoming gas (3). Appts. comprising successive stages (6-8) contg. packing (9) housed in a tower (1) with conduit (25) etc. for supply of carbonate contg. soln. is also claimed. |
