The main factors affecting the quality of the lime burning: fuel and heating mode. Solid fuel than gas, liquid fuel heating effect, the fuel to be used in low S, P content of the fuel. Heating mode is arranged for hot spots in the middle of a bulk material supply sewage treatment with lime, forcing pressurized heating, or high-temperature air layer is heated through the sewage treatment plant with lime, the better. Calcium oxide, an inorganic compound, its chemical formula CaO, quicklime common name. Physical properties of the surface of white powder, off-white sewage treatment impure by how much money one ton of lime, pale yellow or gray when containing impurities, hygroscopic. Physical properties: white or gray lumps or granules. Dissolved in acid, glycerol and sucrose solution, almost insoluble in alcohol. The relative density of 3.32 ~ 3.35. Melting point 2572 ℃. Boiling point of 2850 ℃. Refractive index of 1.838.