China Nonferrous Metallurgy

Waste circuit boards (WPCB) contains a large number of valuable metals and organic matter and glass fiber, of which the copper content accounts for a relatively high proportion of copper recovery in WPCB can not only alleviate the problem of shortage of copper resources, but also solve the problem of environmental pollution of WPCB. Currently, most of the research focuses on the recovery of valuable metal resources in WPCB, and less attention is paid to the organic matter in the non-metallic part. Brominated flame retardants in non-metallic components are dangerous carcinogens, and it is especially necessary to immobilize or recycle bromine in the metal recycling process.The treatment methods of WPCB include pyro-metallurgical process, mechanical treatment, hydrometallurgical process, pyrolysis, microwave treatment technology and biological treatment technology. Among them, although the pyrometallurgical process is the most widely used, the recycling process will produce toxic and hazardous substances, and the process needs to be improved; the separation effect of the mechanical treatment method is not ideal, and it is often used in the pre-treatment of WPCBs; the hydrometallurgical process produces more wastewater, and it needs to be equipped with the corresponding wastewater treatment system; the pyrolysis method can recycle the organic matter and energy, and the recovery of valuable metal resources is high, and it is simple, and it can suppress the production of harmful substances, such as dioxin, and the application prospect is more promising. and other harmful substances, the application prospect is better; microwave treatment technology and biological treatment technology is still in the laboratory stage, need to be in the process parameters, leaching mechanism research, engineering application of in-depth research, to promote the industrialization of the application. In the future, improving the recycling value of non-metallic substances, simplifying the process, reducing the pollutants generated in the recycling process, and studying the migration mechanism of bromine are the research directions for the recycling of WPCB.