Waste Printed Circuit Boards Have Become A Hot Issue In E-waste Processing

As a typical e-waste, its resource research has become a hot issue in e-waste processing. Currently, pyrometallurgy, hydrometallurgy and mechanical/physical methods are the main methods of recovery. Fire and hydrometallurgy aim to recover metals. Residues and toxic fumes from the treatment process can cause serious secondary pollution.

 

The mechanical/physical methods utilize physical processes such as crushing, sieving, sorting, etc. to enrich and separate metals and non-metals, have low environmental pollution, and occupy a dominant position in resource recycling. Existing recycling methods focus on the recovery of metals in the board, and the resources and harmlessness of non-metallic parts are less involved in a total of 50 or more. In addition to a small amount of filler, non-metallic materials are more commonly used as a means of polluting the environment. And hazardous substances have become a new topic in the recycling of used circuit boards.

Pyrolysis is a process in which an organic substance is heated to a certain temperature under anoxic or anaerobic conditions to decompose to form a gas, a liquid (oil), a solid (coke), and recovered. In recent years, organic waste pyrolysis technology has been recycled with low pollution emissions and high energy. The use of pyrolysis technology to dispose of the waste circuit board can not only recover the metal in the circuit board, but also realize the resource utilization of non-metal components and the theoretical research and engineering practice pyrolysis technology of waste circuit boards such as resin.