The 5-Step Process for Plastic Recycling
- 1. Collection– The recycling facilities gather available recyclable plastic material in their area, such as from roadside collections, special recycling bins, or even directly from industries. In this way, both post-consumer and post-industrial plastic items are collected.
- 2. Manual Sorting– All plastic items that are collected are then sorted according to the various plastic types indicated by the plastic recycling symbols and codes on them. Unwanted non-plastic materials found in the piles are promptly taken out.
- 3. Chipping– After sorting, the sorted plastic products are prepared for melting by being cut into small pieces. The plastic items are fed into a machine which has sets of blades that slice through the material and break the plastic into tiny bits, commonly known as regrind or granules.
- 4. Washing– At this step in the process of recycling plastic, all residue of products originally contained in the plastic items and various other ‘contaminants’ (e.g. paper labels, dirt) are removed. A particular wash solution consisting of an alkaline, cationic detergent and water are used to effectively get rid of all the contaminants on the plastic material, making sure that all the plastic bits are clean and ready for the final step. During washing, the wash tank agitator serves as an abrasive, stripping the adhesive off any labels and shredding any paper mixed in with the plastics. The alkaline, cationic detergent (which is similar to the formulas used in shampoos and fabric softeners) is used because plastic materials have a positive surface charge, and only positively-charged chemical compounds (which in this case are cationic detergents) can properly clean them, and effectively remove dirt and grease from the positively charged plastic surfaces.
- Pelleting– The cleaned and chipped pieces of plastic are then melted down and put through a machine called an ‘extruder’ in this stage of the recycling plastic process. The extruder shapesthe melted plastic into thin noodle-like tubes. The plastic tubes are then cut into small pellets by a set of rotating knives. The pellets are then ready to be reused and remade into new items.
What About the Bag?
Plastic bags go through the same five-step process as other plastic products. They too are sorted into their various plastic types, washed and rinsed. However, in the case of plastic bags, they are chopped rather than chipped. The chopped shreds of plastic bags are then melted down during the pelleting stage.
The plastic pellets derived from the recycling plastic process are usually sold by the recycling company to other businesses which would then mold the plastic pellets into an assortment of plastic products for various uses. Some products use a combination of recycled plastic pellets and virgin plastic ones.
Value in Plastic Recycling
Though some people go for fully virgin plastic when available, the demand for recycled plastic products is increasing with the rising awareness of the need to recycle plastics. The value of plastic recycling is undeniable, because recycling cuts down on the need to send plastic waste to landfill. The process creates an avenue to reuse plastic, which is produced from petroleum, a non-renewable resource. Recycling plastic also helps to reduce pollution that arise from the plastic production process as well as the disposal of plastic through incineration and other means (read about the accumulation of plastic debris in theOceanic Garbage Patches).