Polymers, Plastics, and Broken Chains: Recycling’s Biggest Challenge
It has been estimated that just 9{25fae1f33761fe334103c00afec6a8a15622bc4d4a7bdfd12c058052a0f152ce} of the plastic humanity produces gets recycled. The remaining 91{25fae1f33761fe334103c00afec6a8a15622bc4d4a7bdfd12c058052a0f152ce} ends up in landfills, incinerators, or being discarded as litter. This, despite monumental recycling efforts that have been in place since the 1970s. So, what is the problem? It boils down to two things: polymers and breaking chains.
Seraphim Plastics likens the problem to leftovers at the end of a meal. It is nearly impossible to break everything down into base ingredients, then use those ingredients to make other foods. The best you can do is eat the leftovers as-is or mix them into other recipes. Plastic presents the same problem for manufacturers and recyclers.
By the way, Seraphim recycles scrap plastic purchased from commercial entities. They turn everything from production cutoffs to plastic buckets into a regrind product that is ideal for mixing with virgin plastic to make new end products.
1. Plastics are Polymers
Understanding the issues of plastic waste and recycling begins with an understanding of what plastics actually are. Plastics are polymers, which is to say long chains of molecules bonded together. They are made from petroleum. Bio plastics are just now starting to make it to market, but petroleum still rules the day.
Petroleum is processed with heat and chemicals in order to form polymers. Different polymers have different properties. But all polymers consist of molecules so tightly bonded together that breaking those bonds without damaging the molecules is nearly impossible. Each polymer represents a chain that is very difficult to break.
2. Physical Recycling
There are ways to recycle certain types of plastic through physical means. Seraphim Plastics can recycle plastic buckets by sending them through a series of grinders and reducing the material to small pellets that are eventually sold to manufacturers. Likewise, another recycling company can take PET water bottles and reduce them to flake by sending them through a series of shredders.
The goal in both cases is to provide manufacturers with a plastic material they can melt down and mix with new material to make whatever products they make. The process works just fine except for the fact that the recycled plastic loses some of its integrity when it is melted. Thus, mechanical recycling has inherent limits.
3. Chemical Recycling
Physical recycling doesn’t do a particularly good job of breaking up polymer chains to release individual molecules. To do that, companies rely on chemical recycling. By subjecting plastics to liquid or gaseous chemicals, they can heat up polymer chains to a temperature high enough to begin breaking molecular bonds.
As you might expect, chemical recycling is a more complicated enterprise. It is also more costly. Finally, there isn’t much you can do with the recovered molecules except put them back into new plastic products. And just as with physical recycling, chemical recycling causes the molecules to lose some of their integrity.
4. We Do the Best We Can
When you boil plastic recycling down to its simplest form, you discover there really is … Read More..