氧化钙粉末处理高浓度含氟废水的实验研究

Treatment of Wastewater Containing High Concentration Fluorine with Lime Powder

提出以氧化钙粉末代替石灰乳溶液处理高浓度含氟废水 ,可使被处理废水中F-含量降至 <10mg/L ,大大低于国家规定的 <5 0mg/L的排放标准。该方法可节约处理成本 70 %～ 80 % ,回收纯度为 80 %以上的CaF2 和大量的NH3 。实验得出适宜的处理工艺条件 :氧化钙实际用量为理论用量的 1.1倍 ,搅拌时间为 6 0min ,处理温度为 6 0～ 80℃。

The treatment of wastewater containing high concentration fluorine with lime powder instead of lime cream has been studied experimentally. Using the lime powder method, the concentration of fluorine ion in the wastewater, which is as high as 20000 mg/L in the untreated wastewater, can be reduced to <10 mg/L, much lower than the national provided draining criterion of <50 mg/L. Adoption of the lime powder method may reduce 70%～80% of the treatment cost and recover most of NH 3 and CaF 2. The proper treatment conditions obtained from the experiment results are: the expenditure of lime powder is 1.1 times theoretical amount, stirring time is about 60 minutes and the treatment temperature should be kept at 60℃～80℃.