A RECYCLING METHOD OF DIHYDRATE GYPSUM FROM WASTE GYPSUM BOARDS

摘要

Gypsum derived from waste gypsum boards is calcined and converted into gypsum granules comprising hemihydrate and/or anhydrous type III gypsum. The calcined gypsum granules are dropped into water for preparing gypsum slurry. Then, dihydrate gypsum particles are crystalized in the slurry. The temperature of the gypsum granules just before dropped into the water is made 90 °C or higher.