PROCESS FOR RECOVERY AND RECIRCULATION OF CONCENTRATED SULFURIC ACID

The present invention relates to a process for the produc- tion of sulfuric acid from a process gas comprising 1-10 vol% SO₃ and 10-70 vol% H₂O, as well as 1-5000 mg/Nm₃ of particulate solids having a diameter above 1 µm, comprising the following steps: a) condensing sulfuric acid from the process gas by indi- rect heat exchange with a cooling medium, producing a stream of concentrated sulfuric acid, a desulfurized process gas containing sulfuric acid mist and an amount of heated cooling medium, b) removing sulfuric acid mist from the desulfurized pro- cess gas in an acid mist removal step, in order to pro- duce a stream of dilute sulfuric acid and a cleaned gas, c) recycling at least an amount of concentrated sulfuric acid to an upstream process. This has the associated benefit of providing a process for cost effective recycle of SO₃ as sulfuric acid.