Recycling Plastic and What Happens to Plastic When It Goes to be Recycled

Background
Plastic Recycling Codes
What Happens to Plastic When it Goes to be Recycled
Separation
Removal of Contaminants
Processing

Background

Plastics or polymers are largely made from non renewable sources like crude oil, gas and even coal with about 40 different plastics in common use. As the source material is not renewable and many polymers are not biodegradable and can cause major problems in the environment, it is important to recycle plastics. Plastic recycling is made easier by special codes put into the plastic item at the point of manufacture.

Plastic Recycling Codes

Plastic recycling codes come from the The Society of the Plastics Industry, Inc. (SPI) that introduced its resin identification coding system in 1988 after lobbying by recyclers. The recycling codes stamped onto plastic products identify the type of plastic they are made from and therefore simplify sorting of the plastic.

What Happens to Plastic When it Goes to be Recycled

Recycling of plastics happens in 3 stages:

  • Separation
  • Removal of Contaminants
  • Processing.

Separation

Separation is where the plastic identification codes come into play. In mixed recycling streams the plastic is separated from steel, paper, aluminium and other materials sent for recycling. The plastic items are separated into individual polymer types and sent for the next stage in recycling.

Removal of Contaminants

Plastic materials may still have contaminants with them like lids, attachments, some labels, food waste, etc. These contaminants need to be removed before being sent for processing.

Processing

The plastic materials are now free of large contaminants and they are chopped, shredded or ground up into small pieces. The plastic is then washed to remove remnant contaminants. The chopped plastic is processed by melting, mixing and extruding. The extruded plastic is cooled and chopped or pelletised into granules that are used as the raw material for new products.

Source: AZoCleantech

Tell Us What You Think

Do you have a review, update or anything you would like to add to this article?

Leave your feedback
Submit