Production method of zinc oxide

1. Water law

The water method is to use acid, alkali or ammonium carbonate solution, etc., to leach various zinc oxide ore, zinc-containing smoke and other zinc-containing materials. After removing impurities from the clean liquid, precipitating basic zinc carbonate, drying, and calcining, the finished zinc oxide is obtained. Zinc oxide produced by water method is also called active zinc oxide.

2. Fire method

Fire law is divided into direct law (American law) and indirect law (French law).

1) In the direct method, the zinc sulfide concentrate is boiled and roasted, and a carbonaceous reducing agent is added to form a lump (in some cases, no lump is made), and then it is added to a Wetherill furnace. At high temperatures, zinc is reduced and immediately oxidized by CO2 in the furnace gas and oxygen in the introduced air. After cooling, it enters into the bag room to obtain finished zinc oxide (containing 99.5% ZnO). This method can also be used to treat low-grade zinc oxide ore, or various zinc-containing residues, such as flat tank zinc slag, vertical tank zinc slag, etc., to produce external zinc oxide (generally containing 90% to 95% ZnO).

The indirect method is widely used. Indirect methods can be divided into manger furnaces, crucible furnaces, distillation furnaces, reverberatory furnaces and other methods due to different production equipment. The most commonly used are the latter three production methods.