Gypsum beneficiation and processing methods
The beneficiation methods, such as heavy media beneficiation, optical electrical beneficiation, flotation and electrostatic separation, can be used for gypsum beneficiation, but in China, they are not widely used in industrial production. The majority of gypsum is simply hand-selected, they pick other stones out. Some mines are of complex types of ore, in the mining process, the fiber gypsum, cement gypsum, normal gypsum and few anhydrites are hand-selected out.
There are two methods in gypsum calcination process. They are dry calcining and wet calcining. Dry calcining is heating the gypsum for dehydration under the ordinary atmospheric pressure (or low water vapor pressure), along with the generate ofβ-hemihydrate gypsum, Ⅱ-type anhydrous gypsum or burnt gypsum. The gypsum, casting gypsum and pre-products gypsum are commonly used in construction. The wet calcining is hearting under the water vapor pressure in the autoclave or in the low pressure, boiling point higher than 100℃ of the salt solution. Then produces α-hemihydrate gypsum, the basis material to cast a special gypsum.
Gypsum process Plant
β-type gypsum production process generally is: ore storage→crushing →uniform → calcined and dehydrated→aging→grinding and mixture→packaging, first milling then calcination in the calcination process. Dry calcining gypsum process is: run-of-mind gypsum transported from the stope, then stored and selected to ensure continuously feeding and stable quality. The gypsum are fed into primary crusher(jaw crusher) and is crushed into the diameter shorter than 8cm,and then crushed by the secondary crusher(hammer crusher) become the diameter shorter than 2cm. and then delivered by the bucket elevator to the calcining kiln for calcination. By controlling the temperature of the kiln can separately produce β-hemihydrate gypsum, anhydrite gypsum and burnt gypsum. α-type gypsum wet calcination process generally is : gypsum raw materials bin→ screening→ autoclaving and drying → grinding → unifrom →α&βgypsum mixture →packaging and transporting. Hot water production method processing: run-of-mine ore→crushing→grinding→reacting caldron (water and pharmaceutical) →washing→drying→packaging.
Gypsum beneficiation and processing plant Equipment commonly used in gypsum crushing includes jaw crusher, cone crusher, impact crusher, roll crusher, hammer crusher, and so on. The commonly used grinding machines includes ordinary grinding equipment and ultra-fine grinding equipment, like Raymond mill, the European version mill, ultra-fine mill, etc.