| In the process of zinc smelting,the fluoride accompanying the zinc concentrate will dissolve out inevitably.Fluoride can produce corrosion to equipment,increase the consumption of cathode aluminium plate,cause zinc bonding deterioration production environment which affects human health.Therefore it is very strict of fluorine content in zinc smelting,generally requires fluoride content in zinc dipping solution less than 50mg/L.So the subject discusses the study of fluoride removal by goethite method to suit the characteristics of solution produced by a zinc smelter.We carried out tests with different experiment conditions.According to the tests,we evaluated the experiment effect through goethite method 、 the combination of sedimentation and limesedimentation by defluorination and zinc loss.Then according to the experiment results,we finally fix the combination of sedimentation as experiment conclusions.Considering the effect of defluorination and the rate of zinc loss,the optimal conditions for defluorination were as follows: the temperature is 90℃,pH is 4.5,the amount of hydrogen peroxide is 20mL/L,the neutralizing agent is calcium oxide.Under these conditions,the loss rate of zinc is 3.98%,the removal fluoride rate reaches 71.62%,after reaction,the concentration of fluorine is 38.99 mg/L,achieves the requirements of industrial production.In this paper,the using of goethite to remove fluoride helps cutting costs,reducing the purification process.It is feasible in the production process. |
