碱性高浓度含氟工业废水的处理

Treatment of Alkaline Industrial Wastewater with High Fluoride

针对某厂生产过程中产生的碱性高氟废水,以碳酸钙和氢氧化钙的混合物为沉淀剂,在负压环境中通过化学沉淀法对其进行除氟处理。实验结果表明,沉淀剂中碳酸钙和氢氧化钙的比例、反应温度、反应时间等因素均对除氟效果有明显影响。在碳酸钙与氢氧化钙之比为1.5:1,总钙过量10%,反应温度60℃,反应时间120min的条件下,能一次性将废水氟含量降至国家规定的一级排放标准10mg/L以下,且反应产物易分离。

An alkaline high fluoride wastewater from a chemical plant is treated via chemical precipitation process under negative pressure atmosphere, using mixture of calcium carbonate and calcium hydroxide as precipitator. Experimental results show that ratio of calcium carbonate and calcium hydroxide in preclpitator, temperature and reaction timehave significant influences on fluoride removal. When the ratio of calcium carbonate to calcium hydroxide was 1.5 ： 1 while the total calcium consumption was 10 percent more than the theoretical value, the precipitation reaction was carried out for 120 min under 60℃, then the final content of fluorine ion in the treated wastewater was reduced greatly to no more than 10 mg/L all at once, which met the first grade national discharge standard. And the product was easy to separate.