PROCESS FOR PRODUCING PURIFIED GAS FROM GAS COMPRISING H2S, CO2 AND HCN AND/OR COS

摘要

The invention provides a process for producing purified gas from feed gas comprising H2S, CO2 and HCN and/or COS, the process comprising the steps of: (a) contacting feed gas comprising H2S, CO2 and HCN and/or COS with a HCN/COS hydrolysis sorbent in the presence of water in a HCN/COS hydrolysis unit, thereby obtaining gas depleted in HCN and/or COS; (b) contacting the gas depleted in HCN and/or COS with absorbing liquid in an H2S/CO2 absorber to remove H2S and CO2, thereby obtaining the purified gas and absorbing liquid rich in H2S and CO2; (c) heating and de-pressurising at least part of the absorbing liquid rich in H2S and CO2 to obtain hot flash gas enriched in CO2 and absorbing liquid enriched in H2S; (d) contacting the absorbing liquid enriched in H2S 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; and (e) leading at least part of the flash gas enriched in CO2 to the HCN/COS hydrolysis unit and/or to the H2S/CO2 absorber.