PROCESS FOR RECOVERING SULPHUR FROM A H2S-CONTAINING GAS STREAM UNDER HIGH PRESSURE

摘要

A process allows gas streams under high pressure to be desulphurated with comparatively little equipment but with a high recovery rate. For that purpose, H2S is directly oxidized into sulfur by catalysis in at least one reactor. It is advantageous to use two reactors; the first one in the direction of the flow is an adiabatically driven reactor without inner cooling, through which the gas stream flows preferably upwards, whereas the second reactor in the direction of flow is advantageously a reactor interiorly cooled down to a temperature below the dew point of sulphur, through which the gas stream flows preferably downwards. In both reactors, different catalysts are generally used, although both catalysts are essentially composed of TiO2 and oxidize H2S directly and selectively, but not H2 and CO. In the first reactor without inner cooling, H2S is directly and selectively oxidized under high pressure through the catalyst. In the second interiorly cooled reactor, the reaction continues, whereas the sulphur that separates by condensation has in itself a catalytic effect, under the prevailing high pressure. Thus the regeneration of this reactor of liquid sulphur can be dispensed with. The sulphur produced condensates and is separated from the high pressure gas stream. The whole desulphuration process can be further improved by reduction of the sulphur compounds and/or sulphur vapours into H2S and/or by adsorption, chemisorption or NaOH-washing of H2S, the residual sulphur compounds and/or the sulphur vapours.