The indirect method as a raw material the metal zinc ingot or dross, is converted to the zinc vapor in a graphite crucible at 1000 ° C high temperature, and is then blown into the air is oxidized into zinc oxide, and zinc oxide particles were collected in the cooling. The law, also known as the French and France (Le Claire), Leclerc, a French scientist in 1844 to promote the name. The process is simple, indirect method costs by the raw material impact. The product particle diameter of 0.1 to 10 microns, and a purity of 99.5-99.7%. The heavy metal content of zinc ingots or zinc slag a direct impact on the heavy metal content of the product. To total output, the indirect method is the main method for the production of zinc oxide. Zinc oxide produced by the indirect method can be used for rubber, varistors, paint and other industrial products with low heavy metal content which can be used for livestock feed, pharmaceuticals, health care and other industries. Direct method, also known as the USA and France to scrap zinc dross and zinc ash and zinc scrap as raw material, plus carbon combustion generated zinc oxide. Open hearth furnace or converter used in the production. The product purity of the process is relatively low, generally 75-95%. The production process for zinc scrap, or the indirect method zinc oxide resulting crude residue anthracite powder, pellets made of lime, water and slagging agents, air-dried and calcined at 1100-1300 ℃ for 2-3 hours put into the reverberatory furnace after cooling, the zinc oxide products. This year, a new production method called ammonation. The zinc oxide content of 75% of the direct method for the raw materials, 99.7% and 99.9% high purity zinc oxide produced by a special process. The process products as low impurity content of heavy metals such as lead, cadmium direct method zinc oxide, 1/30.