Recovery of sulfur from a hydrogen sulfide containing gas

摘要

The invention relates to a process for the recovery of sulfur from a hydrogen sulfide containing gas, comprising: a. Oxidizing part of the hydrogen sulfide in a gaseous stream with oxygen or an oxygen containing gas in an oxidation stage to sulfur dioxide, and thereafter reacting the major part of the remaining hydrogen sulfide and the major part of sulfur dioxide to elemental sulfur and water, b. reacting the product gas of oxidation stage a) in at least three catalytic reaction systems and c. selectively oxidizing H2S in the gas leaving stage b (in particular leaving) the (last) sub-dewpoint Claus reactor) to elemental sulfur, preferably employing for this purpose a catalytic stage including a selective oxidation catalyst, which is substantially insensitive to the presence of water vapor in the gas stream and is ineffective in promoting the establishment of the Claus equilibrium: 2 H2S + SO2 <==> 2 H2O + 3/n Sn.