Author: Stephane Girois, Ph.D.
Through parts 1 and 2 of this series of articles, we determined that Plastic is a complex material and that we consume and trash a lot of it. The complexity comes from the following facts:
- There are many plastics, and they are very different from one another.
- Most finished plastics products that we use are either a blend of plastics, are made of several plastics parts, or contain large amount of chemical additives (see part 1).
We need to remember that once you put all the plastic items in your trash, there are three possibilities for where they end up: being recycled, incinerated, or landfilled.
Here is the waste management typical process for plastics:
- For appropriate plastic items, they enter the recycle stream in your curbside container. If placed in the wrong container, i.e., the trash container, they will not be recycled but will instead go directly to an incinerator or landfill.
- Our recyclables are sorted by type (paper, plastics, metal, glass).
- Plastics are mostly separated by color: transparent, opaque white, opaque colored.
Once separated by color, plastic wastes are washed, grinded, washed again, dried, and melted, after which they are reshaped into new objects. That is the theory. The reality is significantly more complicated because all of this depends on how much you understand about what is and is not recyclable where you live.
To further understand the recycling process, we need to address some key facts and kill a few myths:
- To be properly recycled, plastic must be washed. A plastic bottle containing residue will not be recycled.
- The code number on the item (see Part 1) is not a reliable way of determining whether or not the item is recyclable as it is not always correct or even visible.
- Plastic is mainly non-biodegradable. Recent innovations using polylactic acid based plastics (made from corn starch mostly) have led to the creation of biodegradable packaging (bags and containers). Fun fact: biodegradable plastics are not recyclable.
- In most US cities and towns, you cannot recycle plastic bags, foam plastics, plastic trays, and many other plastic items.
- To make it simple, the only plastic items that should be recycled are bottles and jugs… and they must be clean.
- In North America, only 27% of all consumed plastic bottles are currently recycled.
The reality is painful. Plastic consumption continues to increase drastically in our modern society. Most plastic items cannot be recycled, and when they are recyclable, negligence and lack of knowledge about the process prevent many plastics from being recycled.
As presented earlier, the other options for disposing of plastics are incineration and landfilling. Since plastics are made preliminary from fossil oil (see Part 1), incineration with the intent to produce energy would make sense. The economic model shows otherwise, and the total cost to incinerate plastics, considering the air pollution factor, can exceed the financial benefit. As a result, 76% by weight of all plastics disposed of in the US in 2015 was landfilled. If we consider that it takes on average 500 years for commodity plastics to decompose in a landfill environment, the least we can say is that we have an enormous issue in front of us.
Recent news announced that China, looking at reducing their pollution situation, would ban the import of recycled plastics by the end of 2017. In 2016, the US exported 3 billion pounds of recyclable plastic waste to China.
It is absolutely critical that we look at our wastes, and plastics in particular, from a completely different perspective. Recycling is a solution but not the only solution.
More to come in Part Four: Plastics and the 6R Management (to be published mid-February)