Sulphur dioxide removal from waste flue gases - - using magnesium oxide and sulphite aq slurry

摘要

The dust-laden gas stream is scrubbed with an aq. soln. so that the SO2 and Mg cpds. in the dust are removed as Mg(HSO3)2. The inert solids are separated, MgO is added to the soln. to give solid MgSO3 which is separated off and the MgSO3 is calcined with the solid portion of the slurry to give regenerated MgO and a dust stream of high SO2 concn. Used to remove and recover SO2 and entrained solid fly ash from gas discharged by coated burning steam power plant or wood pulp processing plant.