【作者】 罗发生；

【导师】 徐晓军；

【作者基本信息】 昆明理工大学 ， 环境工程， 2011， 硕士

【摘要】 作为有色金属行业中的高污染行业,铅锌冶炼排放的含重金属废水对生态环境已构成严重威胁。铅锌冶炼废水主要特征是pH值低,含有浓度较高的硫酸盐以及铜、锌、铅、砷、氟等杂质。目前,铅锌冶炼废水的主要处理方式有中和沉淀法、硫化物沉淀法和铁氧体法等,但是这些方法会产生大量沉渣,其中有用的资源难以回收利用,易造成二次污染,且处理成本高,操作困难。鉴于铅锌冶炼业对环境的不利影响以及目前铅锌冶炼业废水处理中存在的问题,研究开发新型的治理技术迫在眉睫。实验采用单一铁屑法与铁碳微电解对废水的处理效果进行了比较,后续加之絮凝-耦合,为考查对单一Pb2+、Zn2+的处理效果与影响因素,实验除对云南蒙自矿业有限公司的实际废水进行实验外,还配制了含单一离子的模拟废水。实验结果表明,铁碳微电解要比单一铁屑的处理效果要明显,用单一铁屑法处理模拟废水时,Pb2+、Zn2+的最佳去除率分别为77.81%、21.33%,实际废水中Pb2+、Zn2+的去除率分别为78.67%、20.41%；用铁碳微电解法处理模拟废水时,Pb2+、Zn2+的去除率分别为98.25%、56%,对实际废水Pb2+、Zn2+的去除率分别为97.88%、47.29%；对铁碳微电解法出水经过絮凝-耦合处理后,Pb2+、Zn2+模拟废水的去除率分别达到99.82%、99.81%,对Pb2+、Zn2+实际废水去除率分别达到99.90%、99.84%。实验确定铁碳微电解絮凝-耦合法处理云南蒙自矿业有限公司实际废水的最佳工艺为：进水pH值为3,铁碳粒径为40目,铁碳比为2：1,水力停留时间为40min；后续絮凝pH值为9、搅拌时间为10min、静置60min、絮凝过程曝气90min,此时铅锌去除率分别为99.90%、99.84%,出水浓度分别为0.088mg/L,0.25 mg/L,达到排放标准,同时,在此条件下,实际废水中超标的项目Cu2+、Cd2+、砷、F-等,经铁碳微电解絮凝-耦合法处理后,亦能达到排放标准。论文对处理前后铁碳以及絮凝后絮体进行了电镜扫描(SEM)、能谱分析(EDS)和X射线衍射分析(XRD),试图通过对比分析发现其中反应机理、各金属析出的先后顺序及存在形态；论文通过单一铁屑和铁碳微电解的对比,对微电解机理进行了分析；根据实际废水和模拟废水的差异,考察了实际废水中的杂质离子对铁碳微电解的影响。通过上述分析,均取得了相应的的结论。论文还根据实验条件,设计出微电解反应器的结构,并初步设计一套铅锌冶炼废水的处理工艺,并对该工艺处理5%酸度的冶炼废水运行成本进行了估算,结果为处理成本仅为53元/方,于目前其它的方法相比,该法处理成本较低,操作简单等,说明该工艺实际应用具有确实可行性。论文用铁碳微电解絮凝-耦合法处理铅锌冶炼废水,取得了较为理想的效果,为确实解决我国处理铅锌冶炼废水中存在的诸多难题,带来了一种新方法、新手段和新思想。更多还原

【Abstract】 As a highly polluting industry in non-ferrous metals industry, the wastewater of Lead and zinc smelting containing heavy metal pollutants pose a serious threat to the ecological environment. The wastewater of Lead and zinc smelting mainly characterize in having low pH and high concentrate Cu, Zn, Pb, As, F oins. The main treatment methods for the lead and zinc smelting wastewater contain precipitation, sulfide precipitation and ferrite, however, it is difficult to produce the sediment and reuse the useful resources. In other hand, these methods could lead secondary pollution that hard to deal with and need high cost. In view of the adverse effects of lead and zinc smelting wastewater on the environment, it is called out for a tremendous amount of research to be conducted to identify robust new methods of purifying water.The comparison study about the effects of single iron and micro-electrolysis combined with flocculation on wastewater treatment were researched by experiments. To evaluate the effect and influence factors on Pb2+, Zn2+ oins separately, the artifical wastewater was used after using the Mengzi Mining Limited wastewater. The results showed that Fe-C micro-electrolysis is more effective than a single iron. While the Pb2+ and Zn2+ removal efficiencies of artifical wastewater were 77.81% and 21.33% respectely by iron and the date for actual wastewater were 78.67% and 20.41%, the efficiencies by Fe-C micro-electrolysis can reach to 98.25% and 56% for artifical wastewater,97.88% and 47.29% for actual wastewater. After the flocculation following the Fe-C micro-electrolysis treatment, the removal efficiencies of can reach to 99.82% and 99.81% for artifical wastewater respectively, and can reach to 99.90% and 99.84% for actual wastewater. The optimum conditions of the actual wastewater by the coupling micro-electrolysis flocculation treatment as follow:pH 3,40 mesh(Fe-C size), Fe-C ratio 2:1, retention time 40min, flocculation pH 9, stirring time 10min, stationary time 60min, aeration 90 min. The Pb2+ and Zn2+ removal rates were 99.90% and 99.84% at the optimum conditions as the effluent concentration was 0.088mg/L and 0.25 mg/L, which can match the national standards. The actual waste water also can match the national effluent standards after micro-electrolysis coupling flocculation treatment.The reaction mechanism and the metal deposition order for the Fe-C before and after treatment were analyzed by the SEM、EDS and XRD. The mechanism of micro-electrolysis was analyzed by the different between the single iron and Fe-C micro-electrolysis. The impact of impurity ions on the Fe-C micro-electrolysis was also analized by the difference between the artificial solution and actual wastewater. The experimental have a same result with the instrumental anlysis.The structure of micro-electrolysis reactor and the wastewater treatment process were design under the experimental conditions. The operating costs estimate result of 5% acid lead and zinc smelting wastewater showed that it needed 53 yuan for per cubic wastewater. Compared with other tratement methods, the Fe-C micro-electrolysis needs lower cost and easier process, which indicating that the it can be use as a viability application.The micro-electrolysis flocculation obtained ideal results in actual use of dealing with lead and zinc smelting wastewater. It also provided a new method and new technology for how to handle the hot potato of the smelting wastewater of lead and zinc in China.更多还原