电镀工业污染最小化技术

通过分析电镀行业工艺现状,总结了电镀工业废水的产生,特性,现有的治理措施及存在的问题,提出了更新原料,减少用水量及提高回收率污染最小化技术的方案。事实证明,实行污染最小化技术是电镀行业减小污染排放,提高经济效益切实可行的方法。     

不溶性淀粉黄原酸盐聚丙烯酰胺接枝共聚物除铜降浊研究

分别以含Cu2 模拟废水和电镀废水为对象,研究了不溶性淀粉黄原酸盐聚丙烯酰胺接枝共聚物(ISXA)去除Cu2 和降低浊度的能力.论述了该药剂去除Cu2 和降低浊度的优点和机理,探讨了去除Cu 2 的影响因素,如投药量、pH和反应时间.试验表明:(1)对于电镀废水,在5.5倍理论投药量、pH为5.0、反应10 min的条件下,Cu2 去除率为98.89%;当pH≥7时,含Cu2 残渣稳定;在2 mol/L的盐酸和硝酸溶液中浸泡6 h含Cu2 残渣,Cu2 回收率为93.08%;(2)对于含Cu2 模拟废水,在4.5倍理论投药量、pH为5.0、反应10 min的条件下,Cu2 去除率可达99.14%,除Cu2 和降浊存在协同作用.     

Preparation of a metal-phosphate/chromium oxide nanocomposite from Cr(III)-containing electroplating sludge and its optical properties as a nanopigment

A nanocomposite composed of metal-phosphates and chromium oxide was prepared from a Cr(III)-containing electroplating sludge (CES) by a facile three-step (extraction–precipitation–calcination) process. Optimal process parameters were determined, and the structure of the metal-phosphate/chromium oxide nanocomposite (MPCON) was investigated by field-emission scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. The results show that the optimal extraction pH is 2.0. The MPCON presents a polyhedral morphology with average particle size of around 100 nm. The components of MPCON vary from AlPO₄/Cr₂O₃ to Mg₃(PO₄)₂/AlPO₄/Cr₂O₃ at different solution pH during precipitation. Meanwhile, the optical performance of the nanocomposite as a pigment is discussed. The reflectance of MPCON-6.5 in the near-infrared range is around 56%, making it a strong prospect to be used as a functional pigment in energy-efficient buildings. This study proposes a novel recycling process for the conversion of CES into high-value products, which is beneficial for the treatment of waste.     

Copper stabilization in beneficial use of waterworks sludge and copper-laden electroplating sludge for ceramic materials

A promising strategy for effectively incorporating metal-containing waste materials into a variety of ceramic products was devised in this study. Elemental analysis confirmed that copper was the predominant metal component in the collected electroplating sludge, and aluminum was the predominant constituent of waterworks sludge collected in Hong Kong. The use of waterworks sludge as an aluminum-rich precursor material to facilitate copper stabilization under thermal conditions provides a promising waste-to-resource strategy. When sintering the mixture of copper sludge and the 900 °C calcined waterworks sludge, the CuAl₂O₄ spinel phase was first detected at 650 °C and became the predominant product phase at temperatures higher than 850 °C. Quantification of the XRD pattern using the Rietveld refinement method revealed that the weight of the CuAl₂O₄ spinel phase reached over 50% at 850 °C. The strong signals of the CuAl₂O₄ phase continued until the temperature reached 1150 °C, and further sintering initiated the generation of the other copper-hosting phases (CuAlO₂, Cu₂O, and CuO). The copper stabilization effect was evaluated by the copper leachability of the CuAl₂O₄ and CuO via the prolonged leaching experiments at a pH value of 4.9. The leaching results showed that the CuAl₂O₄ phase was superior to the CuAlO₂ and CuO phases for immobilizing hazardous copper over longer leaching periods. The findings clearly indicate that spinel formation is the most crucial metal stabilization mechanism when sintering multiphase copper sludge with aluminum-rich waterworks sludge, and suggest a promising and reliable technique for reusing both types of sludge waste for ceramic materials.     

电镀废水中硫氰酸根离子含量的自动电位滴定

研究了用自动电位滴定测定硫氰酸根离子的条件和方法。实验结果表明,选用银电极为指示电极,217型双液接电极为参比电极,在硝酸介质中滴定硫氰酸根离子,方法具有高选择性; 应用于电镀废水分析,方法简便快捷,在4min内能打印出分析结果。     

电镀重金属废水处理技术的研究进展

电镀废水成分复杂,含有铬、铜、锌、镉、镍等多种重金属,处理难度较大。介绍了当前电镀废水处理技术及新进展,分析了各方法的优缺点,并对发展趋势进行展望。     

电镀重金属污泥的水泥固化／稳定化处理

电镀重金属污泥经425号水泥固化后;其中混凝土:污泥为40:1或50:1样本的强度(28d)可达275号水泥的标准,且对Zn、Cu、Ni、Cr离子的固化效果好;在体系中添加粉煤灰及水玻璃,其早期的固化效果或产物强度低;混凝土:铁氧体污泥(湿法合成,FeSO_4·7H_2O:污泥=4:1)为30:1体系中,固化效果与稳定性均好,且产物强度可达325号水泥标准。     

上海市电镀废水及其重金属污泥处置现状

对上海５００多个电镀厂（点）两次调查结果表明，１９９０年与１９８５－１９８６年相比，虽然电镀生产增长约２．１倍，金属总耗量仅增加５．２％，其中毒性最大的铬耗量从占金属总耗量约１０．２％下降到７．６％；工艺用水采用全封闭或半封闭循环的厂（点）增至４９．０％，电镀废水排放量减少２２．９％；化学法处理废水的厂（点）从５５．２％增至６６．１％离子交换和电解法分别从３０．７％、７．８％降至２２．０％、３．８     

电镀行业清洁生产技术应用

针对电镀行业的特点，介绍了清洁生产技术，重点分析靖江市在推行电镀业清洁生产过程中的技术应用及取得的社会、经济及环境效益。     

电镀行业清洁生产方案

通过分析电镀行业工艺现状，总结了电镀行业废水的产生、特性、现有的治理措施及存在的问题，提出了更新原料、减少用水量及提高回收率等清洁生产方案