| abstract |
The present invention relates to a process and a process plant for the production of sulfuric acid from a gas comprising H 2 S and HCN characterized by the following steps; directing said gas to an alkaline absorber containing a liquid ammonia absorbent solution and a material catalytically active in oxidation of H 2 S to elemental sulfur providing a liquid slurry comprising sulfur and coke oven gas absorber liquid, separating at least a portion of said elemental sulfur from coke oven gas absorber liquid by mechanical means of separation as a sulfur sludge, combining said sulfur sludge with a support fuel and a first gas comprising oxygen in or upstream an incinerator, incinerating said mixture, providing an incinerated gas comprising SO 2 and NO x , optionally adding a second gas comprising oxygen to said incinerated gas, selectively removing the formed NO x by chemical reduction with NH 3 , contacting said process gas with a material active in oxidation of SO 2 to SO 3 providing an oxidized process gas, optionally adding water to said oxidized process gas and condensing concentrated sulfuric acid formed in said oxidized process gas. |