PROCESS FOR PRODUCING A PURIFIED SYNTHESIS GAS STREAM

摘要

A process for producing a purified synthesis gas stream from a carbonaceous feedstock, the process comprising (a) oxidizing a carbonaceous feedstock to obtain syngas containing hydrogen sulphide, (b) mixing the synthesis gas with methanol, reducing the temperature of said mixture and separating a liquid methanol-water mixture from a cooled syngas, (c) contacting the cooled syngas with methanol to decrease the content of hydrogen sulphide and carbon dioxide thereby obtaining a rich methanol stream comprising hydrogen sulphide and carbon dioxide, (d) regenerating the rich methanol stream by separating from the rich methanol a carbon dioxide fraction and a hydrogen sulphide fraction to obtain lean methanol, wherein part of the methanol in the methanol-water mixture obtained in step (b) is isolated and reused in step (b) and/or (c) and wherein another part of the methanol in the methanol-water mixture obtained in step (b) is recycled to step (a).