Waste circuit board crushing, sorting and recycling process
At present, most of the domestic waste circuit boards are treated with primitive methods. For the rare or precious metal parts of the circuit boards, incineration or strong acid dissolution is used, that is, the precious metals are left after removing other components. This process will produce a lot of “three wastes”. Because there are no environmental protection measures, it is quite harmful to the environment and laborers, and these resources are not fully and effectively used. E-waste is a precious resource. Strengthening the research and application of metal recycling technology for e-waste is of great significance both from an economic and environmental point of view. Due to the complex and diverse characteristics of e-waste, it is difficult to recover the metal in it with any technology alone. The future development trend of e-waste processing technology should be: industrialization of processing forms, greater recycling of resources, and scientific processing technology .
Aiming at the current situation of domestic processing of waste circuit boards, improving the metal recycling rate, reducing the burden of environmental pollution, the comprehensive treatment technology of green recycling of recycled metal from waste circuit boards, adopting green and efficient crushing and sorting technology, the metal and non-metal in waste circuit boards Physical separation prevents environmental pollution caused by incineration and acidolysis.
Using all physical methods, optimizing the combined process of crushing-re-selection-electrical separation to realize efficient circuit board crushing and effective separation of metals and non-metals. The combination of coarse crushing, medium crushing, grinding and screening and classification processes can greatly improve the grinder The efficiency is reduced, the load of the grinder is reduced, and the effect of energy saving is achieved. At the same time, the life of key components of the crusher and grinder can be extended. Re-separation of metal and non-metal in metal powder containing impurities such as organic matter by the combined process of gravity separation and electrical separation, greatly reducing the organic content in the metal powder.
The physical method of environmental protection circuit board recycling equipment is a method of recycling using mechanical means and PCB physical properties. The green and efficient crushing and sorting process of waste circuit boards is to physically separate metals and non-metals in waste circuit boards, and the purpose of crushing It is to dissociate the metal in the waste circuit board from the organic matter as much as possible to improve the separation efficiency. The study found that when the metal is broken at 0.6 mm, the metal can basically reach 100% dissociation.