Fenton氧化-混凝沉淀处理电镀废水中重金属镍的研究

以某电镀厂含镍废水为处理对象,探究Fenton氧化-混凝沉淀工艺对重金属镍的去除效果。结果表明,Fenton氧化的最佳条件为:H₂O₂投加量2 mmoL/L、FeSO₄/H₂O₂摩尔比0.6、初始pH值5、反应时间80 min;混凝沉淀的最佳条件为:pH值9、PAC用量12 mg/L、混凝时间12 min、助凝剂用量6 mg/L、沉降时间60 min;在此最佳条件下,Fenton氧化-混凝沉淀工艺处理含镍电镀废水,镍去除率可达99.8%,出水总镍含量低至0.029 mg/L,处理后的出水水质满足《电镀污染物排放标准》(GB21900—2008)表Ⅲ要求。

Treatment of Heavy Metal Nickel in Electroplating Wastewater with Fenton Oxidation and Coagulation Precipitation

The nickel-containing wastewater of an electroplating plant was treated in an experiment by adopting Fenton oxidation and coagulation precipitation process, for studying the removal effect of heavy metal nickel. The results show that under the following optimum conditions, the Fenton oxidation with H₂O₂ dosage of 2 mmoL/L, FeSO₄/H₂O₂ molar ratio of 0.6, an initial pH of 5, the reaction time of 80 min, followed by the coagulation and precipitation process with pH of 9, PAC dosage of 12 mg/L, reaction time of 12 min, coagulant dosage of 6 mg/L and settling time of 60 min, can lead to the nickel removal rate up to 99.8% and the total nickel content in the effluent as low as 0.029 mg/L. It is shown that the quality of the effluent after the treatment has met the requirements stated in Table Ⅲ of Electroplating Pollutant Discharge Standard (GB21900-2008).