摘要：
含氟废水会对环境造成巨大危害，但传统钙盐法难以实现含氟废水达标排放。为解决某光伏企业的高氟废水处理问题，本研究对实际生产废水进行研究，确立了一级钙盐联合二级混凝的工艺路线，并对高氟废水进行单因素实验和正交试验，以钙盐种类及投加量、反应pH、混凝剂种类为变量，以出水残氟质量浓度为考察指标，为工程应用确定了一种合适的除氟工况。结果表明，影响除氟效果的因素依次为钙氟物质的量比>二级混凝反应pH>复合除氟剂（DAMW-03）用量>一级钙盐反应pH。最优除氟工况为：一级钙盐反应以CaCl2为钙源，钙源投加量为理论钙氟物质的量比（0.5）的1.25倍以上，并使用Ca（OH）2调节pH=8；二级混凝反应可添加50 mg/L PAC或复合除氟剂（DAMW-03），控制pH在5~7，最终可实现中性出水且出水ρ（F-）可稳定小于5 mg/L。一级钙盐法联合二级混凝法可使高氟废水稳定达标排放，具有处理效率高、试剂易得、处理成本较低等优点。
关键词:
含氟废水,
钙盐沉淀,
混凝沉淀,
正交试验
Abstract:
Fluorine-containing wastewater does great harm to the environment，but the traditional calcium salt method is difficult to achieve the standard discharge of fluorinated wastewater. In order to solve the problem of high fluorine wastewater treatment in a photovoltaic enterprise，the experiments were conducted on the wastewater which came from enterprise production. The process route of the first-order calcium salt combined with the secondary coagulation was established. The single factor experiment and orthogonal experiment were carried out on the high fluorine wastewater. Taking the types and dosage of calcium salt，pH and types of coagulant as variables，and the residual fluorine concentration as the investigation index，a suitable defluorination condition was determined for the engineering application. The experimental results showed that the factors affecting the fluoride removal efficiency were in the order of ratio of calcium to fluoride>secondary coagulation reaction pH>composite defluorination agent（DAMW-03） dosage>first-order calcium salt reaction pH. The optimal defluorination conditions were as follows：the first-order calcium salt reaction could use CaCl2 as the calcium source，the amount of CaCl2 added was more than 1.25 times of theoretical ratio of calcium to fluorine（0.5），and Ca（OH）2 was used to adjust pH=8，50 mg/L PAC or composite defluorination agent（DAMW-03） could be added to the secondary coagulation reaction，and controlled pH between 5-7. Finally，neutral effluent could be achieved，and ρ（F-） of the effluent could be stably less than 5 mg/L. The first-order calcium salt method combined with the second-stage coagulation method could make the high-fluorine wastewater stably meet the discharge standard. It had the advantages of high treatment efficiency，easy availability of reagents and low treatment cost.
Key words:
fluorinated wastewater,
calcium salt sedimentation,
coagulation sedimentation,
orthogonal experiment
中图分类号:
崔兵, 金怡, 杨泽坤. 钙盐-混凝法处理高氟废水的实验研究[J]. 工业水处理, 2023, 43(6): 150-155.
Bing CUI, Yi JIN, Zekun YANG. Research on the treatment of high fluoride wastewater by calcium salt-coagulation method[J]. Industrial Water Treatment, 2023, 43(6): 150-155.