摘要 |
Purificn. of a gas contg. combustible components, CO2 and S cpds. (esp. H2S) is carried out by scrubbing with a scrubber soln. which is regenerated by expansion, stripping and hot regeneration, H2S-rich off-gas from the hot regeneration being processed to elementary S and an H2S-contg. residual gas which is contacted with scrubber soln. The novelty comprises (i) partially combusting the H2S-rich off-gas with oxygen(-contg. gas) or air in a combustion chamber to produce a gas mixt. at 1000-2000 deg.C contg. at least 30 mol.% of the introduced sulphur as elementary S and contg. H2S and SO2 in the molar ratio 4-1:1; (ii) cooling the gas mixt. to below the dew point of elementary S and separating the condensed S; (iii) heating the gas mixt. to 180-200 deg.C and subjecting it directly to catalytic hydrogenation and/or hydrolysis to convert residual SO2 into H2S; and (iv) contacting (part of) the treated gas, as H2S-contg. residual gas, with scrubber soln. |