Synthesis of αCaSO4· from flue gas desulfurization gypsum ...
1. Introduction Flue gas desulfurization gypsum (FGD gypsum), which is mainly composed of CaSO 4 ·2H 2 O (DH), is the industrial waste residue produced by the limestonegypsum wet process of flue gas desulfurization technology. The bulk deposition of FGD gypsum not only takes up plenty space, but also results in land and water pollution.