E-Waste Recycling

andrewcheng | Recycling | 02/23/2011

I’ve been meaning to do a piece on e-plastic recycling (plastic from electronic waste) for some time now. This is because I did a good amount of e-plastic trading last year. I purchase baled computer and television cases from the United States and import them into China for separation and processing.

E-waste plastic, sometimes called “e-plastic,” is composed of plastic stripped from electronic equipment such as computers, monitors, telephones, etc. Why not just grind and melt the e-plastic together and turn them back into electronic equipment?

Here lies the problem, before e-plastics can be melted and turned into recycled plastic resin, it must first be separated into its plastic type. E-plastic is usually composed of the following types: ABS, ABS (flame-retardant), ABS-PC, PC, PS, HIPS, PVC, PP, PE, and more. Each type of plastic has it’s own melting point and properties and cannot be combined for product manufacturing.

So the question now is, how do we separate everything?

While things are done quite differently in the United States (more automated due to higher wages), I’ve been lucky enough to visit an e-plastic separation plant here in Shanghai, China where most things are done manually. You can click the pictures below to see clearer, full-sized images.

According to the owner of the facility, a majority of the e-plastics the e-waste recycling plant process are imported from European countries and the United States. The quality of plastic from these countries, as a whole, is better.

When I say manual, I really mean it! This is the first process for e-plastic separation in China. The larger pieces are hand separated by experts that can differentiate between 7-10 plastic types just by looking, feeling, and burning it. At the same time, the workers must remove any metal (ie., screws), circuit boards, and wires found. As you see in the video, they’re REALLY fast at sorting. I questioned the owner about accuracy of all this. He arrogantly replied, “the accuracy is up to 98%, if this was not the case, I would not have any customers buying my stuff…”

Once the large pieces are separated, they are put through the shredding and rinsing apparatus here. The resulting plastic flakes are sun dried and ready to be packaged and sold.

For the smaller e-plastic pieces that cannot be hand separated, they are put through several tubs of liquids with varying salinity and chemical content. From what I understand, one of the containers contain only water. Due to the densities of PP and PE, these plastics will naturally float to the top.

The plastic at the bottom are then scooped and placed in another tub that contains salt, cleaning agent, and other chemicals. At this time, the ABS and HIPS (without flame retardants) can be separated from the rest of the group. I didn’t get into too much detail with the owner. I didn’t want to have the owner feel like I was prying information from him. Plus, the chemical makeup in these e-plastic recycling tubs is probably trade secret.

This is what the plastic flakes look like once separated. The picture above is white PP flakes and is ready for production or further processing into PP pellets which can be sold for much higher prices.

The is the storage facility for separated e-plastics, they are ready to be sold for profit. The capacity for this e-waste recycling facility is separating 500 metric tons per month. Before the end of this year, the owner hopes to increase to 1000 metric tons.

The metals are sold to other facilities that deal specifically with metal recycling.

These pieces are too small to separate and are thrown away as trash.

The inevitable by-product of e-waste recycling, pollution…