Zinc is a silver-white slightly bluish metal with a density of 7.14g/cm³ and a melting point of 419.5 ° C. It is fragile at room temperature; When 100 ~ 150℃, it becomes soft; After 200℃, it becomes dry again. The chemical properties of zinc are active, and in the air at normal temperature, a thin and dense basic zinc carbonate film is generated on the surface, which can prevent further oxidation. When the temperature reaches 225℃, zinc oxidizes violently.

Zinc burns poorly in air and emits a strong white light in oxygen. There is a layer of zinc oxide on the surface of zinc, burning white smoke, the main component of white smoke is zinc oxide, not only block zinc combustion, will refract the flame color to form a pale light. Zinc is easily soluble in acid, and it is also easy to replace gold, silver, copper, etc., from the solution. The melting point of zinc oxide film is high, but the melting point of zinc metal is very low, so the zinc sheet is heated on the alcohol lamp, and the zinc sheet melts and becomes soft, but does not fall, precisely because of the role of the oxide film. Zinc is mainly used in steel, metallurgy, machinery, electrical, chemical, light industry, military and medicine and other fields.

Zinc oxide can be used in medicine, chemical industry, paint, pigment and other industries, under the background of the rapid development of China's economy, the demand for zinc oxide in industrial production continues to increase. Zinc oxide is mainly obtained by rotary kiln smelting, which is widely popular in our country.

Lead-zinc smelting is to enrich zinc in slag and then treat the slag with fuming furnace to produce zinc oxide or zinc secondary oxide. In our country, the leaching slag produced by blast furnace is fumed by rotary kiln to obtain zinc oxide or secondary zinc oxide.

Treatment of zinc oxide by rotary kiln:
The production of low grade zinc oxide is a direct production process with rotary kiln as the main equipment, known as the Wiltz process, also known as the rotary kiln volatilization process. The treatment process is: all kinds of zinc-containing materials (mainly water quenched slag or zinc leaching slag) and coke powder or anthracite crushed coal are mixed in a certain proportion, and are put into the rotary kiln through the kiln tail feeding pipe. When the rotary kiln rotates, the material slowly rolls forward, and under the forced blast, the kiln forms a high temperature reaction zone of 1000 ~ 1200℃. Under this condition, the zinc metal compound in the charge is in contact with the reducing agent carbon, and is reduced by C and CO into zinc metal vapor into the gas phase, in the gas phase is oxidized into zinc oxide dust by the oxygen in the air, which is collected with the flue gas into the dust collection system, and the captured dust is a low-degree zinc oxide product. In addition, metals enriched with zinc (such as lead, indium, etc.) are also reduced and oxidized into the product, while copper and precious metals gold and silver remain in the kiln slag.

Characteristic:

1.  Zinc oxide rotary kiln equipment configuration is simple, reduce investment costs, improve productivity.

2.  Zinc oxide rotary kiln has high dressing efficiency, good quality of zinc oxide obtained by calcining and smelting, and small amount of nodulation.

3. The whole zinc oxide production line runs smoothly, the production capacity is large, and the fuel cost is greatly reduced in the smelting process.