Method of treating a gaseous mixture comprising hydrogen, carbon dioxide and hydrogen sulphide

A method of treating a gaseous mixture, comprising CO2, H2, H2S, optionally CO, and optionally one or more additional combustible components, to obtain an H2 or H2 and CO product stream (H2/CO product stream) and a CO2 product stream, the method comprising:

• separating the gaseous mixture to provide the H2/CO product stream and a CO2 enriched stream, the CO2 enriched stream containing at least one combustible component selected from H2S, H2, CO and any additional combustible components present in the gaseous mixture;
• obtaining a support fuel stream comprising one or more combustible components, wherein said support fuel stream is a gaseous stream derived from the production of the gaseous mixture, is a portion of the gaseous mixture, is separated from the gaseous mixture in addition to the H2/CO product stream and CO2 enriched stream, is a portion of the H2/CO product, or is derived from the H2/CO product;
• combusting the support fuel stream, in the presence of sufficient O2 to combust all or substantially all of the combustible component(s) present in said support fuel stream, to form a stable flame to act as the ignition source for combustion of the combustible component(s) present in the CO2 enriched stream;
• contacting the CO2 enriched stream, said flame and sufficient O2 to combust all or substantially all of the combustible component(s) present in said CO2 enriched stream and form a combustion effluent comprising CO2 and the combustion product(s) of the combustible component(s) of the support fuel and CO2 enriched streams;
• and
• forming the CO2 product stream from said combustion effluent.