METHOD OF REMOVING SULPHUR COMPOUNDS AND CARBON DIOXIDE FROM GAS STREAM Russian patent published in 2011 - IPC B01D53/48 B01D53/62 

FIELD: chemistry.

SUBSTANCE: method of removing sulphur compounds and carbon dioxide from hydrocarbon gas stream containing at least 50 vol. % C₁-C₄ hydrocarbons and sulphur compounds, including hydrogen sulphide and mercaptans by (a) washing the hydrocarbon gas stream with an aqueous amine solution to remove hydrogen sulphide, carbon dioxide and part of the mercaptans to obtain a first purified gas stream, (b) passing the first purified gas stream through one or more molecular sieves to further remove mercaptans and obtain a second purified gas stream, (c) contacting the second purified gas stream and a hydrogen stream with a hydrogenation catalyst to obtain a third purified gas stream, and (d) passing the third purified gas stream through one or more hydrogen sulphide adsorbent beds to obtain purified gas. The start-up method involves supply of water vapour at step (c) during the start-up period when there is no hydrogen or when there is shortage of hydrogen, arising through conversion of the purified gas to synthetic gas. Synthetic gas is obtained from the purified gas. Hydrogen obtained from the synthetic gas gradually replaces water vapour.

EFFECT: high efficiency of removing sulphur compounds.

12 cl, 1 dwg, 1 ex