Modified gypsum treatment principle: as a mineral containing CaSO4, in nature there are two stable forms: one containing two crystal water, called gypsum; volume one is ibuhan crystal water, add anhydrite. Usually heard plaster, gypsum is. Called anhydrite anhydrite. Days of burning process characteristics projecting plaster that when a rotary kiln calcination of gypsum, produced at different temperatures with different characteristics of the product, when the rotary kiln temperature is 65 ~ 70 ℃ when starting dehydrated gypsum into hemihydrate gypsum ; continue to heat to 200 ℃ or less, gypsum dewatering, the hemihydrate gypsum into anhydrite, but there is contact with water is very fast condensation of gypsum; temperature exceeds 200 ℃, condensation slow; 200 ~ 300 ℃ key generation anhydrite, condensation is slower, but after coagulation strength; 300 ~ 450 ℃ The product is anhydrite, though rapid coagulation. But mild lower; 450 ~ 700 ℃ between the chemical composition of the product has not yet changed, but to produce a new variant, called burnt gypsum, it is extremely difficult to dissolve in water, water does not condense, no strength; heated to 800 ℃, condensation and hardening slowly anhydrite; 800 ~ 1000 ℃ free lime is generated, a very valuable ordinary calcined gypsum; continue to heat to above 1000 ℃ increase of free lime, calcined gypsum to generate fast clotting. Used in industry hemihydrate gypsum is formed by rotary calcining natural gypsum, also known as plaster or gypsum, plaster and water, mixed with a certain proportion, a plastic body, after a time, into a solid. Just to form a solid, the strength is low, as the physical and chemical characteristics, intensity will continue to increase. Please indicate Henan YuFeng Heavy Machinery