Non toxic and harmful components of waste circuit board

The Electronic Product Recycling Branch of China Material Recycling Association organized a seminar on the recycling and management of waste PCB circuit boards, which was attended by relevant personnel from the Solid Waste and Chemical Management Center of the Ministry of Environmental Protection, industry associations, waste electrical and electronic product dismantling enterprises, PCB circuit board treatment and disposal enterprises, etc. The participants discussed the recycling management of waste PCB circuit boards, the management and disposal of waste PCB circuit board components.

According to current regulations, waste PCB circuit boards are hazardous wastes

It is understood that PCB circuit boards are the main parts and key disassembly products of discarded electrical and electronic products, also known as PCB circuit boards or printed PCB circuit boards. According to the provisions of the National Catalogue of Hazardous Wastes and the Guidelines for Disassembly, Disposal and Production Management of Waste Electrical and Electronic Products (2015 Edition), PCB circuit boards are hazardous wastes and should be classified and stored in a centralized manner. Off site treatment should be handled by a unit with a hazardous waste business license and a corresponding business scope.

According to the requirements of the Guidelines for Qualification Examination and Licensing of Waste Electrical and Electronic Products Disposal Enterprises, the disposal enterprises should have the sorting, packaging and other equipment suitable for the disposed waste electrical and electronic products. For printed PCB circuit boards, the Guidelines for Licensing pointed out that: according to the used process, corresponding equipment or devices and facilities must be available, and listed the requirements for three treatment processes: pyro, wet and mechanical methods, Those who do not use or dispose of hazardous waste by themselves shall be entrusted to the unit with a hazardous waste business license and corresponding business scope for use or disposal.

Compliance disposal of waste PCB circuit boards is difficult to track

What is the actual processing of the PCB circuit board? At the meeting, the staff of the Association explained according to the survey:

1. Disassembling enterprises basically hand over the waste PCB circuit boards generated from disassembly to local or nearby qualified PCB circuit board processing enterprises according to the requirements; Some dismantling enterprises have the qualification of PCB circuit board treatment, but most of these enterprises adopt the crushing and sorting method to treat the waste PCB circuit boards, and only a few large enterprises have the ability of advanced treatment.

2. The small workshop still carries out the disposal of waste PCB circuit boards, and conducts the next disposal according to the value of electronic components, tin and optical boards: electronic components can be reused after passing the inspection; Tin can be directly melted and poured into lead tin alloy; The waste PCB circuit board is refined by simple wet process to obtain precious metals.

3. Some of the few copper smelting enterprises deal with low-grade waste copper with a few low-grade waste PCB circuit boards; Due to the limitation of price and access to waste PCB circuit boards, such enterprises are faced with an embarrassing situation of shortage of waste PCB circuit boards.

According to the statistics of relevant data, there are 186 enterprises processing PCB circuit boards in China, and 139 enterprises with definite annual processing capacity, with a total annual processing capacity of nearly 820000 tons. However, it is difficult to track whether the hazardous waste treatment enterprises with waste PCB circuit board treatment qualification dispose the waste PCB circuit boards generated from the disassembly of household appliances in compliance.

The survey shows that the waste PCB circuit boards generated from the dismantling of household appliances may be transported for a second time without being disposed in compliance with the regulations. Some waste PCB circuit board disposal enterprises resell the waste PCB circuit boards. Waste PCB circuit boards may flow to Guiyu, Guangdong, one of the distribution centers of waste electrical and electronic products. According to the survey, there are 2-3 "environmental protection furnaces" outside the local park of Guiyu for large-scale disposal of waste PCB circuit boards. Each furnace handles more than 30,000 tons of waste PCB circuit boards annually and is still in operation.

Can non-toxic and harmful components be "exempted"?

It is understood that the main components of the PCB circuit board are the substrate and electronic components. The main components are metal, oxide, organic matter, glass fiber, epoxy resin and other non-metallic components. At present, the components basically do not contain environmentally sensitive substances. The PCB circuit board contains brominated flame retardant, lead solder and a small amount of other precious metals, which are easy to cause environmental risks and have certain harmfulness in case of improper disposal.

There are a certain amount of reusable components on the waste PCB circuit board, and the reuse of components has formed a large-scale market. After discussion, some participants believed that the list of domestic hazardous wastes included waste PCB circuit boards and components in the category of hazardous waste management, which virtually increased the difficulty of waste PCB circuit boards treatment and disposal, increased the burden on enterprises, and was not conducive to environmental protection and comprehensive utilization of resources. Some participants suggested that the components stripped from waste PCB circuit boards that have reuse value and do not contain toxic and harmful substances should be exempted from the list of hazardous wastes, and the remaining other components and bare PCB circuit boards should be handed over to enterprises or facilities with the disposal qualification of cost PCB circuit boards for effective environmentally sound treatment and disposal, so as to maximize optimal disposal.

For PCB circuit board processing and metal extraction, some experts put forward the proposal of "recycling of disassembled materials, harmless treatment process, scientific process selection, and industrialization of scale development". As for the industrialization development, experts said that the quantity of electronic waste recycled by a single enterprise could not reach the minimum value of large-scale operation. Although some enterprises independently established some small-scale treatment devices, they often failed to achieve the precision and quality of industrialization, and the cost was upside down. It can integrate large-scale related industries, give play to comparative advantages and advanced production factors, gather multiple materials, open up channels, and form a stable raw material supply chain to achieve large-scale operation.