What is the Plastic Recycling Process?
A Look at How Plastic is Processed During Recycling
As you now likely know, there are many types of plastics, and even within various plastic categories there are variations that result in a myriad of plastic types now in the consumer chain. When all of this plastic ends up at the recycling facility, the challenge of turning it all from waste into new useful products can be pretty big, with sorting one type from another the largest problem. Composite products made with several types of plastic as well as metal and glass all stuck together further complicate matters.
As a result, not all plastics are recycled in every city, town, or county, and the types of plastic recycling processes used will vary depending on the available facilities. Nevertheless, here are some basics on plastic recycling to give you an idea of what goes into this challenging industry:
- #1 PET plastic recycling process: Postconsumer PET plastic is baled into large blocks of compact plastic and shipped to a recycling facility where it is then shredded into tiny flakes. After being washed, the flakes are melted down and extruded into pellets. These are then sold to manufacturers who use it to make new plastic products.
- #2 HDPE & #4 LDPE plastic recycling process: Generally, since HDPE and LDPE plastics can be repeatedly softened and reformed, plastic #2 and #4 recycling starts with melting down the material. It is then pushed through an extruder to either form a new product (such as plastic lumber) or small pellets which are shipped to manufacturers to be re-formed into other products.
- #3 PVC plastic recycling process: When PVC can be recycled, it must be broken down into its original formulation components, which is incredibly difficult to do. Through the Vinyloop® process, it can be put through a dissolution and filtration process to precipitate out the compounds in microgranule form. Large-scale, sustainable methods for recycling PVC have yet to be developed, however.
- #5 PP plastic recycling process: Polypropylene plastic can often be recycled in the same process as PETE plastic which is more cost effective than recycling it separately. When recycled, it can be made into similar products to their original form, or into something new.
- #6 PS plastic recycling process: Polystyrene can be melted down and formed into solid blocks of plastic which are sold to companies as raw materials for making new products. These densified blocks take up 90% less space than the original foam products.
- #7 plastic recycling process: How #7 plastics are recycled depend entirely on their make-up, but the processes used can range from mechanical recycling (melting, shredding, or granulating waste plastics into flakes which are then made into granules) or chemical recycling (breaking down polymers into constituent monomers, which are then refined into usable raw materials).