With the development of technology, people's requirements for residential decoration are getting higher and higher, and the rise of building gypsum can meet people's requirements. Building plaster is a kind of white and delicate powder, it is generally suitable for interior decoration, plastering, whitewash. Because it is more white than lime and it also has condensation hardening fast, condensation hardening volume micro expansion, porosity, has a certain humidity, good fire resistance five characteristics. Therefore, the building plaster has become a kind of popular material for present interior decoration.
The raw materials of building gypsum are mainly natural gypsum, it is containing calcium sulfate (also known as raw gypsum) or chemical by-products containing calcium sulfate and waste residues such as phosphogypsum, fluoro-gypsum and boron gypsum. Its chemical formula is CaSO4.2H2O, also known as dihydrate gypsum. Different kinds of gypsum can be obtained by calcination of natural dihydrate gypsum at different temperatures. Such as natural dihydrate gypsum in 107~1700c dry conditions heating can be obtained.
