Label：PCB Recycling, Squeezing Crushing, Precious Metal Elements
Nov 5, 202112680
Any item will be damaged if it is used continuously, especially for electronic products. However, the damaged item is not completely waste and can be recycled. The same is true for PCB. Moreover, with the advancement of science and technology, the number of electronic products has increased sharply, shortening their use cycles, and many products are discarded without being damaged, leading to serious waste.
Products in the electronics industry are updated very quickly, and the number of discarded PCBs generated therewith is also very staggering. Every year, there are more than 50,000 tons of discarded PCBs in the UK. Recycling is the principle of resource conservation and green production. Moreover, there are some substances in electronic products that are harmful to the environment, and recycling is inevitable.
Common metal elements: aluminum, copper, iron, nickel, lead, tin, zinc, etc.;
Precious metal elements: gold, palladium, platinum, silver, etc.; rare metal rhodium, selenium, etc.
PCB also contains a large number of high-molecular polymers directly or indirectly derived from petroleum products, which have a high calorific value. They can be used to produce energy and related chemical products. Many of the ingredients are toxic and harmful, and if discarded, they will cause great pollution.
The PCB template is composed of a variety of elements, even if it cannot be used normally, the elements can still be recycled. So, how to recycle, JRPanel will briefly introduce the steps for everyone:
The surface of the PCB is coated with protective metal, and the first process of recycling is to remove the paint. Paint removers include organic paint removers and alkaline paint removers. Organic paint removers are highly toxic and harmful to the human body and the environment. It can be dissolved by heating with sodium hydroxide, corrosion inhibitor, etc.
After the PCB is dismantled, it will be crushed. There are methods such as impact crushing, squeezing crushing and shearing crushing. The more commonly used is the ultra-low temperature freezing and crushing technology, which can cool tough materials, make them brittle and crush them, so that metals and non-metals are completely dissociated.
The pulverized material needs to be sorted according to the density, particle size, magnetic permeability, conductivity and other characteristics of its various components. Usually there are dry and wet sorting. Dry separation includes dry sieving, magnetic separation, electrostatic, density and eddy current separation. Wet separation includes hydrocyclone classification, flotation, hydraulic shaker, etc. The sorted substances can be reused.