【作者】 赵越；

【导师】 崔崇威； 纪峰；

【作者基本信息】 哈尔滨工业大学 ， 环境工程， 2011， 硕士

【摘要】 本课题模拟水源水分别受到镍（Ni）、铅（Pb）、镉（Cd）污染,考察了常规混凝-沉淀工艺对原水中该三种重金属的去除效果,并对温度、浊度、混凝剂种类与投加量、pH等可能对重金属去除产生影响的条件进行了研究比较,同时对KMnO₄与粉末活性炭在强化混凝-沉淀工艺对重金属的去除效能进行了研究,并考察了不同超标倍数下和多种重金属复合污染原水的最优去除条件。水厂现有工艺,对分别受到镍、铅、镉污染的源水均有一定的去除效果,但均无法达标处理。原水的温度对重金属的去除效果无明显影响,在混凝剂PAC、PFS、PAFC投量分别达到80、80、90 mg/L以上时,低温与常温下重金属去除效果差别不大,且浊度对于重金属去除的影响几乎不存在。综合比较PAC、PFS、PAFC在不同投量下对于镍、铅、镉的去除效果,发现PAC在投加量为90mg/L时去除效果最好,且不产生二次污染,但仍无法将重金属污染处理达标。提高反应的初始pH可以显著提高重金属的去除效果,当反应初始pH分别提升至9.9、8.1、10.2时,受镍、铅、镉污染源水处理后可以达标。KMnO₄和粉末活性炭对于重金属的去除均有一定的效果,单独使用的去除效果均已经优于常规的混凝-沉淀工艺,联用时对重金属污染去除效果提升显著:镍在KMnO₄、粉末活性炭投加量分别为0.3、20mg/L,pH为9.0时;铅在KMnO₄、粉末活性炭投加量分别为0.3、10mg/L,pH为7.5时;镉在KMnO₄、粉末活性炭投加量分别为0.5、20mg/L,pH为9.3时,可以将三种重金属污染处理达标。采用以上混凝条件为本课题所选工艺的最佳的强化混凝条件。同时,略提高原水的pH和KMnO₄投量即可以将高超标倍数下与多种重金属的复合污染的原水在之前优选的混凝条件下处理达标出水。更多还原

【Abstract】 This subject simulated that the source water was polluted by the Nickel （Ni）, lead （Pb）, cadmium （Cd）,and the effects of removal of the three heavy metals by conventional coagulation - precipitation process on the source of the water were studied. Temperature, turbidity, coagulant type and dosage, pH may affect the removal of three heavy metals,and the author compared the differences. Meanwhile, the removal efficiency of heavy metals by potassium permanganate and powdered activated carbon in the coagulation - precipitation process was studied. When the source water was polluted by different times exceeded heavy metals or kinds of heavy metals, the optimal removal conditions were discussed.Existing conventional water coagulation - precipitation process had effect on removal of nickel, lead, cadmium three kinds of heavy metal. But they could not meet the standards. The temperature of source water had no significant effect to the removal of heavy metals .When the dosage of PAC, PFS and PAFC reached 80,80,90 mg/L or more, the removal of heavy metals had little difference at low temperature and room temperature. And the turbidity almost had no effect to the removal for heavy metals.Comprehensive comparing the removal of nickel, lead, cadmium under different dosage of PAC, PFS, PAFC, the author found that the removal was the best in the dosage of PAC 90mg/ L, without secondary pollution. But the water after treatment could not meet the standards.Improving the initial pH in thereaction could significantly improve the removal of heavy metals. when the initial pH during the reaction time was increased to 9.9,8.1,10.2,the source water polluted by nickel, lead, cadmium could meet the standards after treatment.KMnO₄ and powdered activated carbon had a certain effect for the removal of heavy metals. The removal effect using KMnO₄ or powdered activated carbon alone were already better than the conventional coagulation - precipitation process .And the combination of KMnO₄ and powdered activated carbon could obtain significant effect: the dosage of KMnO₄ and powdered activated carbon were 0.3 mg/L,20 mg/L and pH was 9.0; the dosage of KMnO₄ and powdered activated carbon were 0.3 mg/L,10 mg/L and pH was 7.5; the dosage of KMnO₄ and powdered activated carbon were 0.5mg/L, 20mg/L and pH was 9.3. The above conditions were the best coagulation conditions which could make 5 times standard limit of the heavy metal meet the standards.Under these three conditions the polluted water by three heavy metals could meet the standards after treatment. The above coagulation conditions were the best of enhanced coagulation conditions in this subject.The slight increase of the pH of the water source and KMnO₄ dosage could make the water that high exceeding and combined polluted by various heavy metals to meet the effluent standards by the optimal coagulation condition above.更多还原