膜分离技术处理电镀废水的实验研究

采用纳滤＋反渗透2级处理系统浓缩回收电镀铜漂洗废水。实验结果显示：在△P=1．5MPa条件下进行浓缩．纳滤膜可以使料液浓缩近10倍。纳滤膜对Cu^2＋的截留率在96％以上，对COD的截留率在57％以上。在△P=3．0MPa条件下进行浓缩，反渗透膜可以使料液浓缩近10倍。反渗透膜对Cu^2＋的截留率在98％以上，对COD的截留率在67％以上。随着料液浓度的增加，纳滤膜和反渗透膜的截留率会降低。     

电镀重金属污泥的处理及综合利用现状

简要综述了目前工重金属污泥近几年的处理及综合利用状况，包括固化，填海等方法，其中重点介绍了铁氧化体法固化电镀污泥重离子的湿法、干法工艺流程，以及用污泥生成的铁氧体为原料，可生产颜料、油漆和磁性探伤粉等较高档产品。     

原子吸收火焰法次灵敏线测定污水和电镀污泥中高含量的锌

对采用原子吸收火焰法次灵敏线测定污水和电镀污泥中高含量的锌进行了研究。试验结果表明：在锌浓度50．0～600．0mg/L之间,溶液锌含量与吸光度呈线性关系。线性回归方程为y＝0．000661x-0．0007,相关系数γ＝0．9998。方法检出限为25．0mg/L,相对标准误差（RSD）＜2．96％,加标回收率为92．5％～105％,与标准法的相对误差＜2．76％。     

电镀企业竣工环保验收监测及后续监管中存在问题探讨

结合电镀企业竣工环保验收监测工作实践,对单位产品基准排水量和排气量的计算和评价,电镀标准中对污染物处理设施排气量的规定,第一类污染物在不同采样点评价标准的选择,重金属排放总量计算以及后续电镀企业废水、废气、污泥监管中存在的问题进行了探讨,并提出了相应的建议。     

电镀污染区植物重金属积累特征研究

采用野外采样室内分析方法,对泰州某电镀污染区12种优势植物和对应土壤中的Cu、Cr、Cd、Pb和Ni5种重金属含量进行测定,揭示了优势植物对复合污染重金属的富集和转运特征。结果表明,该电镀污染区土壤中Cd平均含量为4.10 mg/kg,是GB15618—2008《土壤环境质量标准》中二级标准9.1倍。植物吸收重金属的富集滞留在地上部较多,香樟对Cd,双穗雀稗、野艾篙、牛筋草对Cu,双穗雀稗对Cr,三叶草、蒲公英对Pb,双穗雀稗、苣荬菜对Ni表现出重金属植物修复的潜力,它们是修复Cd污染土壤的理想植物。     

The NICE-Whyco technologies partnership: saving energy, dollars, and the environment in the metal plating industry

In partnership with the US Department of Energy’s Office of Industrial Technology, Whyco Technologies, Inc., has developed an innovative perforated plating barrel used in the plating of metal parts. This new technology employs a thin-walled construction, differing from the traditional thick-wall design required to provide adequate structural integrity. The thicker walls lowered the efficiency of transferring plating solution into and out of the barrel and diminished the electrical current pushed through the holes and onto the parts being plated. By machining pockets out of the traditional thick-walled perforated structure, Whyco produced a ‘honeycomb’ of staggered cells, allowing for the greatest number of holes per open area while maintaining structural integrity. Hydrodynamic pumping occurs during barrel rotation to create greater solution transfer than in traditional barrels. The Whyco barrel has higher current density plating, which leads to faster plating cycles, reduced bath concentration, and better plating of difficult chemistries such as in alloys. This new technology has helped the company reduce energy use by 16%, eliminate more than 480 tons/year of solid waste, and reduce wastewater by more than 17 000 gallons/day. The resulting cost savings total more than $500 000 annually. The company has manufactured and sold more than 275 of these barrels to other electroplating companies that are reporting up to a 40% increase in plating productivity and similar energy and environmental impacts.     

Recovery of Ni(II) from real electroplating wastewater using fixed-bed resin adsorption and subsequent electrodeposition

Resin adsorption and subsequent electrodeposition were used for nickel recovery. Treated wastewater can meet the Electroplating Pollutant Discharge Standard. The spent resin is completely regenerated by 3 BV of 4% HCl solution. 95.6% of nickel in concentrated eluent was recovered by electrodeposition. Effective recovery of high-value heavy metals from electroplating wastewater is of great significance, but recovering nickel ions from real electroplating wastewater as nickel sheet has not been reported. In this study, the pilot-scale fixed-bed resin adsorption was conducted to recover Ni(II) ions from real nickel plating wastewater, and then the concentrated Ni(II) ions in the regenerated solution were reduced to nickel sheet via electrodeposition. A commercial cation-exchange resin was selected and the optimal resin adsorption and regeneration conditions were investigated. The resin exhibited an adsorption capacity of 63 mg/g for Ni(II) ions, and the average amount of treated water was 84.6 bed volumes (BV) in the pilot-scale experiments. After the adsorption by two ion-exchange resin columns in series and one chelating resin column, the concentrations of Ni(II) in the treated wastewater were below 0.1 mg/L. After the regeneration of the spent resin using 3 BV of 4% (w/w) HCl solution, 1.5 BV of concentrated neutral nickel solution (>30 g/L) was obtained and used in the subsequent electrodeposition process. Using the aeration method, alkali and water required in resin activation process were greatly reduced to 2 BV and 3 BV, respectively. Under the optimal electrodeposition conditions, 95.6% of Ni(II) in desorption eluent could be recovered as the elemental nickel on the cathode. The total treatment cost for the resin adsorption and regeneration as well as the electrodeposition was calculated.     

高浓度电镀废水的处理

介绍了某自行车厂电镀车间高浓度电镀废水处理工艺的设计；结合工艺运行的调试，对设计缺陷进行了分析。     

Cadmium—Towards a rational use of a toxic element

Because of its toxicity, cadmium creates an environmental problem as well as a health hazard for exposed workers. Most cadmium emissions arise from the intentional use of the element. It is therefore mandatory to reduce cadmium consumption to the lowest possible level. Cadmium pigments, mainly used in plastic processing, can be replaced in all applications where the processing temperature does not exceed 300°C. Newly developed polyvinyl chloride stabilizers promise to be an excellent substitute for cadmium stabilizers in even the most demanding applications. Cadmium plating, still extensively used in the United States and the West Germany, has been virtually abandoned in Japan. Improved lead acid batteries are replacing vented nickel cadmium batteries because of their cost effectiveness. While in these applications cadmium use is declining, more and more cadmium is needed for the manufacturing of sealed nickel cadmium batteries. These relatively small electrochemical cells are used mainly by individual consumers. Here cadmium can only be replaced in some marginal applications. The high cadmium content of these batteries (up to 22%) makes them a good candidate for recycling of the heavy metal.     

电镀废水中微量铜的测定方法

在NaF和NaAc存在下，直接测定电镀废水中的微量铜，该方法具有良好的选择性和灵敏度。