Mechanical recycling: A look inside one of many ways to recycle plastic

Wednesday, May 15, 2024
HOUSTON, Texas (KTRK) -- For the past two weeks, ABC13 Meteorologist Elyse Smith has covered how the City of Houston manages recycling, specifically looking at how plastic is recycled.

And when it came to seeing where those recyclables are taken, both to the sorting facilities and recycling facilities themselves, ABC13 was denied access to each. So, there was no way to show where your recycling went once it was dropped off at a local recycling station or from your doorstep.

That said, Eyewitness News was able to visit the University of Houston's engineering lab to see one way plastic can be recycled.

That process is called mechanical recycling, in which recycling is sorted to separate the plastic. Then, the plastic is chopped, melted in an extruder, and shaped in an injection molder. While the process does make plastic recyclable, sometimes the quality of the plastic can be impacted.

"Through the recycling process, the properties of the materials and how they behave can be changed drastically. Which means you can't use them in the same applications that they started in," Dr. Megan Robertson, a professor at the University of Houston, said.

SEE ALSO: Does recycling actually make a difference? New report details how there's a 'plastic waste crisis'
New report details how there's a 'plastic waste crisis'

[Ads /]
Furthermore, one reason why recycling plastic is harder than it looks is because of how many different kinds of plastic there are. There are at least seven different kinds of recyclable plastic, and no two can be recycled together. This makes the process of recycling plastic tedious and expensive.

Yet another reason why recycling for plastic might not be as prevalent as you think is a claim made by the Center for Climate Integrity in their report "The Fraud of Plastic Recycling."



ABC13 spoke to Davis Allen, one of the investigative researchers for the Center For Climate Integrity about their report.

"The process of collecting, sorting, cleaning, processing, plastic waste just means that it can never be viable, as when competing against virgin resins or resins that are made for the first time from oil and gas," Davis said. Researchers with the Center for Climate Integrity state that's one reason why petrochemical companies won't spend the money to make plastic recycling a viable option.
[Ads /]
But the next generation of engineers are hopeful that will change with their inventions. Ph.D. candidate Ronard Herrera is working hard at UH to research how everyday plastics can be recycled and made into new materials for durable goods.

In the meantime, Robertson confirmed that only 10% of the world's plastic is being recycled to date. The rest is either incinerated, put in a landfill, or ends up in unwanted locations like nature.



Over the course of this three-story recycling series, ABC13 showed you the recycling process here in Houston, specifically the mechanical recycling for plastics that they're doing at the University of Houston. As for the advanced recycling that the big oil companies say is happening even locally here in Southeast Texas, we have requested tours.

For more on this story, follow Elyse Smith on Facebook, Twitter and Instagram.
Copyright © 2024 KTRK-TV. All Rights Reserved.