电镀污泥的焚烧预处理及资源化与无害化处理研究

【作者】 廖昌华；

【导师】 孙水裕； 刘如意；

【作者基本信息】 广东工业大学 ， 环境工程， 2003， 硕士

【摘要】 本研究以铜和镍为主要重金属的电镀污泥作为研究对象，提出了“焚烧——综合利用——无害化”的处理工艺，并对焚烧、浸出、除杂净化、无害化过程的工艺条件与机理进行了研究。试验结果表明：该工艺能高效的回收污泥中的有价金属铜和镍，同时，整个工艺产生的废水、废渣在进行适当的处理后，可以满足有关要求，不会对环境造成危害，达到资源化及无害化的双重目的。 焚烧预处理能大幅度减少电镀污泥中的水分，同时能减少其体积及重量，从而使污泥中的金属含量得到提高，这为后续浸出过程创造了极为有利的条件，对提高整个处理工艺的经济效益大有益处，适宜的焚烧温度是600℃左右。 对焚烧后的电镀污泥渣进行浸出时发现，酸浸效果要远好于氨浸，铜和镍的浸出率都保持在较高水平。浓硫酸浸出试验的最佳的工艺条件是：污泥渣的给料细度为-74μm占77％，液固比为3：1，每克干污泥加浓硫酸0.35mL，浸出时间1h，常温。用铁屑置换浸出液中铜的效果很好，能制得较高质量的海绵铜。采用适宜的除铁方法，能有效的去除置换后液中的杂质，与此同时，镍的损失不大。从得到净化的镍溶液中，可以制取质量较好的硫酸镍产品。 工艺产生的废水在控制合适的pH值或通过添加硫化钠的方法，可以达标排放，满足污水综合排放要求。产生的固体废渣在采用渣：水泥：砂：煤灰重量比为1：2：1.5：0.3的配比进行固化处理后，固化效果良好，可以达到安全处置的要求。因此整个工艺产生的废物均不会对环境造成危害。 经济分析后发现，处理该焚烧后的电镀污泥是有利润空间的，该技术是具有经济和环境双重效益的。本试验在工艺流程上有所创新，技术切实可行，设计参数合理，对实际生产有指导意义。更多还原

【Abstract】 A new technology is developed, described as incineration-leaching- innoxious disposal. It is used to treat the electroplating sludge in which the primary heavy metals are copper and nickle. The mechanisms of incineration, leaching and purifying of this technology are investigated. The results have shown that the copper and nickle can be leached mostly, and the waste water and solid waste produced in leaching process can be treated properly and do not have adverse effects on the environment.Incineration is used to pretreat the electroplating sludge in order to reduce the volume and weight of sludge and enrich contents of heavy metals in electroplating sludge, which is important for enhancing benefit in all processes. The best incineration temperature is about 600 癈.The electroplating sludge incinerated is leached using acid and ammonia. The results have shown that the acid leaching is better than the ammonia leaching. The optimum conditions of the acid leaching are: the fineness of raw material is less than 74um, the ratio of water/solid is 3, acid dosage is 0.35mL per gram dry sludge, leaching time is Ih, the room temperature is used. The copper in leaching solution can be effectively replaced by iron shaving. An appropriate method of purifying the leaching solution can remove impurities effectively and reduce nickel loss. The high-quality product of nickel can be made from the purified solution.The waste water produced in the leaching process can be purified by controlling the value of pH or adding Na2S. The solid waste also can meet the standard of safe disposal after solidification using cement, sand and coal ash. So, the wastes have no bad impact to the environment.Through economical analysis, it can be concluded that it is profitable to treat the electroplating sludge using the new method. In our investigation, there are innovations in technology, and the parameters are suitable, so the technology has guidable meaning to the plant application.更多还原