An Overview of Plastic Recycling

Plastic recycling refers to the process of recovering waste or scrap plastic and reprocessing the materials into functional and useful products. This activity is known as the plastic recycling process. The goal of recycling plastic is to reduce high rates of plastic pollution while putting less pressure on virgin materials to produce brand new plastic products. This approach helps to conserve resources and diverts plastics from landfills or unintended destinations such as oceans.

Plastics are durable, lightweight and inexpensive materials. They can readily be molded into various products which find uses in a plethora of applications. Every year, more than 100 million tons of plastics are manufactured across the globe. Around 200 billion pounds of new plastic material is thermoformed, foamed, laminated and extruded into millions of packages and products. Consequently, the reuse, recovery and the recycling of plastics are extremely important.

There are six common types of plastics. Following are some typical products you will find for each of plastic:

PS (Polystyrene) – Example: foam hot drink cups, plastic cutlery, containers, and yogurt.

PP (Polypropylene) – Example: lunch boxes, take-out food containers, ice cream containers.

LDPE (Low-density polyethylene) – Example: garbage bins and bags.

PVC (Plasticised Polyvinyl chloride or polyvinyl chloride)—Example: cordial, juice or squeeze bottles.

HDPE (High-density polyethylene) – Example: shampoo containers or milk bottles.

PET (Polyethylene terephthalate) – Example: fruit juice and soft drink bottles.

Currently, only PET, HDPE, and PVC plastic products are recycled under curbside recycling programs. PS, PP, and LDPE typically are not recycled because these plastic materials get stuck in the sorting equipment in recycling facilities causing it to break or stop. Lids and bottle tops cannot be recycled as well. “To recycle or Not to Recycle” is a big question when it comes to plastic recycling. Some plastic types are not recycled because they are not economically feasible to do so.

• Every hour, Americans use 2.5 million plastic bottles, most of which are thrown away.
• About 9.1% of plastic production was recycled in the U.S. during 2015, varying by product category. Plastic packaging was recycled at 14.6%, plastic durable goods at 6.6%, and other non-durable goods at 2.2%.
• Currently, 25 percent of plastic waste is recycled in Europe.
• Americans recycled 3.14 million tons of plastics in 2015, down from 3.17 million in 2014.
• Recycling plastic takes 88% less energy than producing plastics from new raw materials.

The simplest of plastic recycling processes involves collecting, sorting, shredding, washing, melting, and pelletizing. The actual particular processes vary based on plastic resin or type of plastic product.

Most plastic recycling facilities use the following two-step process:

Step One: Sorting plastics automatically or with a manual sort to make sure all the contaminants are removed from the plastic waste stream.

Step Two: Melting down plastics directly into a new shape or shredding into flakes then melting down before being finally processed into granulates.

Ongoing innovations in recycling technologies have made the plastic recycling process easier and more cost-effective. Such technologies include reliable detectors and sophisticated decision and recognition software that collectively enhance the productivity and accuracy of automatic sorting of plastics. For an example, FT-NIR detectors can run for up to 8,000 hours between faults in the detectors.

Another notable innovation in plastic recycling has been in finding higher value applications for recycled polymers in closed-loop recycling processes. Since 2005, for example, PET sheets for thermoforming in the UK can contain 50 percent to 70 percent recycled PET through the use of A/B/A layer sheets.

Recently, some EU countries including Germany, Spain, Italy, Norway, and Austria have begun collecting rigid packaging such as pots, tubs, and trays as well as a limited amount of post-consumer flexible packaging. Due to recent improvements in washing and sorting technologies, the recycling of non-bottle plastic packaging has become feasible.

Plastic recycling faces many challenges, ranging from mixed plastics to hard-to-remove residues. The cost-effective and efficient recycling of the mixed plastic stream is perhaps the biggest challenge facing the recycling industry. Experts believe that designing plastic packaging and other plastic products with recycling in mind can play a significant role in facing this challenge.

The recovery and recycling of post-consumer flexible packaging is a problem. Most material recovery facilities and local authorities do not actively collect it due to a lack of equipment that can efficiently and easily separate them.

Oceanic plastic pollution has become a recent flashpoint for public concern. Ocean plastic is expected to triple in the next decade, and public concern has prompted leading organizations around the world to take action towards better plastic resource management and pollution prevention.