Flue gases: Gypsum dewatering in desulphurisation

The combustion of sulphur containing fossil fuels requires downstream flue gas cleaning, which is often accomplished by wet processes. This is where the raw flue gas is cleaned in an absorption wash tower where the sulphur dioxide reacts with an aqueous slurry of limestone to form gypsum. Roland Küspert and Gernot Krammer of Andritz describe the process and ways in which it can be optimised.