Effects of Soluble Ions on Hydration of Calcined Flue Gas Desulphurization Gypsum

The influence of various water soluble cations (K^+, Na^+, Ca^2+, Mg^2+) on the hydration of calcined flue gas desulphurization gypsum was investigated. The results show that all cations but Ca^2+ can accelerate the hydration of bassanite. The final crystal size is not largely influenced by different salts, except for Na^+, where the giant crystal with length of >130 μm is observed. Current study clarifies the influence of different ions on the hydration of bassanite, which could provide sufficient guide for the pre-treatment of original flue gas desulphurization gypsum before actual application.