PROCESS FOR PRODUCING PURIFIED SYNTHESIS GAS

摘要

Disclosed is a process for producing a purified synthesis gas stream from a feed synthesis gas stream. The process includes contacting the feed synthesis gas stream with a water gas shift catalyst in a shift reactor and in the presence of water to obtain a shifted synthesis gas stream enriched in H2S and in CO2. H2S and CO2 are removed from the shifted synthesis gas stream by contacting the shifted synthesis gas stream with an absorbing liquid to obtain semi-purified synthesis gas and an absorbing liquid rich in H2S and CO2. At least part of the absorbing liquid rich in H2S and CO2 is heated to obtain heated absorbing liquid rich in H2S and CO2 that is then flashed to obtain a flash gas rich in CO2 and absorbing liquid rich in H2S. That absorbing liquid rich in H2S is contacted at elevated temperature with a stripping gas thereby transferring H2S to the stripping gas to obtain regenerated absorbing liquid and stripping gas rich in H2S. H2S in the stripping gas rich in H2S is converted to elemental sulphur, and H2S is removed from the semi-purified synthesis gas by converting H2S in the semi-purified synthesis gas to elemental sulphur to obtain the purified synthesis gas.