Patent ID: 8431105

Claim:
A method for producing process gas containing hydrogen sulfide and sulfur dioxide for the Claus process, starting from feed gas that contains hydrogen sulfide which is burned with pure oxygen at temperatures in the range of 800 to 1650° C. by means of several burners opening out into a combustion chamber where through one central tube each the pure oxygen is routed into the combustion chamber while the feed gas enters it through a tube arranged coaxially around the central tube and purge gas is added through an annular duct coaxially surrounding the feed gas tube and where in an auxiliary firing space connected to the combustion chamber and arranged at a distance from the burners, water vapor is fed through the central tube, heating gas through a tube coaxially surrounding the central tube, and sour water stripping gas is supplied through an external tube arranged coaxially around the heating gas tube, the combustion gases arising from the auxiliary firing space being conducted to the combustion chamber, said method comprising the use of inert gas as purge gas.