Analysis the effect of removing fluorine and chlorine from zinc oxide dust by wet alkali washing

This paper focuses on the technology of removing fluorine and chlorine from zinc oxide dust using alkali washing, by studying the removal effect of fluorine and chlorine in different zinc oxide dusts during the alkali washing process, and adopting a gradual extraction method to detect the state of fluorine in zinc oxide dust and alkali washing residue, and analyzing the influencing factors of fluorine removal from a mineralogical perspective. The results show that the chlorine in bag filter zinc oxide dust and boiler zinc oxide dust is easily removed by alkali washing, while the fluorine in boiler zinc oxide dust is more difficult to remove than that in bag filter zinc oxide dust, with more than 50% of residual fluorine and a large amount of calcium fluoride, zinc sulfide and iron sulfide with low solubility in alkaline environment, resulting in a low fluorine removal rate for boiler zinc oxide dust. The state of fluorine in zinc oxide dust is the key factor affecting the fluorine removal effect.