Composition and general characteristics of limestone: limestone calcination to more than 900 ℃ (generally 1000 ℃ ~ 1300 ℃) when decomposed into lime (CaO), lime sales emit CO2. Lime (CaO) FGD system is an important absorber. Limestone in metallurgy, building materials, chemical industry, light industry, construction, agriculture and other special industries are important industrial raw materials. With the strengthening of energy conservation work, buy lime powder, limestone in the field of environmental protection will be more widely used. Lime: lime in steelmaking applications. It is mixed with molten steel, having a rapid slagging (slag) removal rate and improve the S (sulfur) removal of P (phosphorus) efficiency. Active lime used in the process of steelmaking also has: shorten the refining time, lime, improve the furnace, lower raw material consumption, increase production, quality, reduce costs, stable operation is conducive to smelt the advantages of automation.