Effects of soluble ions on hydration of calcined flue gas desulphurization gypsum

The influence of various water soluble cations (K+, Na+, Ca2+, Mg2+) on the hydration of calcined flue gas desulphurization gypsum was investigated. The results show that all cations but Ca2+ 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.