An Overview of Plastics Recycling
In the 70 years that plastics have been produced, humankind has made 8.3 billion tons of this useful material. Of the 8.3 billion tons of plastic made, 6.3 billion tons have been thrown out as garbage. Of the 6.3 billion tons that have been thrown out, only nine percent have been recycled.
Recycling or reusing plastics is part of a larger effort to create sustainable economic ecosystems that do not damage the environment and wreak havoc on other parts of the economy. Current waste management methods involving the waste generation and disposal leave much to be desired. The estimated cost in damage and losses to the fishing, aquaculture, and other industries and environmental damage stands at $2.5 trillion.
Efforts to control and minimize the damage have been ongoing since the 60s. The importance of the issue and the consequences of failing to control ever-increasing plastic waste has given this issue new urgency. The general goal is to avoid plastics from making it to landfills, where it will take them hundreds of years to decompose. Mixing recyclable plastics with non-recyclable plastics or processing recyclable plastics contaminated by chemicals or food remnants hinders the recycling process. It would most likely result in more plastics in landfills.
Apart from mixing recyclable and non-recyclable plastics, some plastic products are composed of a plastic mix or are made by mixing plastic with wood or metal. This kind of material mix prevents such items from being recycled. The plastics recycling process comprises several steps: collection, sorting, washing, shredding, separation, and compounding.
Collection is the retrieval of used plastics from homes, businesses, and other institutions. This may be done through the efforts of households and businesses with the support of local governments or through private enterprises that actively collect plastic. With the plastic on hand, recyclers sort the plastic according to its type. Further sorting criteria involve thickness, color, and use.
The presence of contaminants such as chemicals and food remains can hinder the recycling process. Washing helps prevent this occurrence. Aside from the contaminants mentioned, plastics for recycling are washed to remove trace adhesives and product labels.
After washing, the plastic is shredded. In the shredded form, the plastic may already be reused. An example of reuse would be as an asphalt additive. Shredded plastic also allows for the removal of more impurities. For example, a magnet is used on shredded plastic to remove trace metals that have been mixed in.
Water and wind are then employed to separate the plastics further. The shredded plastic is floated in the water and separated according to density. The plastic is also placed in a wind tunnel and separated according to thickness.
The final step, known as compounding, crushes and melts the shredded plastic and molds them into pellets. These pellets can then serve as the raw material for manufacturing facilities that reuse the plastic.
Although the recycling process is a step in the right direction, there is room for improvement. The recycling process produces VOC or volatile organic compounds. These are fumes that are harmful to plant and animal life and the people working in the recycling plant. VOCs also prevent recycled plastics from having wide use as food containers since the VOC can leach into the food.
Another drawback is that once the plastic has gone through the recycling process, it cannot go through another recycling process. This means that recycling extends plastic use, but eventually, even recycled plastic will landfills.
