Gypsum is a common kind of air hardening gelled material,Its main component is calcium sulfate(CaSO4).Our country is lack of high quality and high grade gypsum products,and most of gypsum in our country are middle and low grade products,high-grade decorative gypsum products and medical gypsum products still need to be imported from abroad.Gypsum resources are non-renewable,in order to save resources and long-term development of the society,at the same time,based on the necessity of environmental protection,...