Megan Hall: Welcome to Possibly, where we take on huge problems like the future of our planet and break them down into small questions with unexpected answers. I’m Megan Hall.
A few months ago, we did an episode about how the US only recycles about a third of the glass that we use. But there’s actually a lot more to the story.
We had Leo Nachamie and Nat Hardy from our Possibly Team look into it.
Leo Nachamie: Hey Megan!
Nat Hardy: Hello!
Megan Hall: Okay, so refresh my memory… why isn’t glass getting recycled?
Leo Nachamie: Well, there’s two main things to consider -first…what to do with the glass: where to transport it, and what to turn it into. That’s what we talked about last time….
Nat Hardy: But there’s another factor to consider---the quality of the glass: how uniform it is, the cleanliness, and the color.
Megan Hall: Tell me about that!
Leo Nachamie: Let’s follow a glass bottle in the US. Once it’s made at a glass factory, it’s shipped to a store where someone buys it.
Nat Hardy: Then someone brings it home, uses whatever is inside, and then hopefully recycles it.
Leo Nachamie: But that last step, recycling the glass bottle, looks different depending on where you live. And this can impact its value.
Megan Hall: Don’t we all just put our recycling into one bin?
Nat Hardy: That’s one system…
Collin Wilkinson: In the United States, single stream, curbside pickup is the most common. You put all your recyclables in one bin. Somebody with a big truck comes along, picks it all up, takes care of it, sends it off.
Nat Hardy: That’s Collin Wilkinson, an assistant professor of glass science and engineering at Alfred University.
Leo Nachamie: He says there’s also multi-stream recycling. Instead of everything going into one bin, households sort out their recycling by material, and it’s picked up by different trucks.
Megan Hall: But either way, the glass bottle I recycled goes to the same place, right?
Leo Nachamie: It depends. With multi-stream, sometimes glass is brought right to specific processors. Other times glass is brought to recycling plants, like the single stream stuff.
Nat Hardy: At those plants, everything gets sorted into what can and can’t be recycled.
Leo Nachamie: As you might expect, recycling that’s all mixed together needs a lot more sorting.
Collin Wilkinson: So the sorting technology can range everywhere, from incredibly sophisticated machines that is able to use air streams to actually singularly push off a shred of glass into the right bin. This is incredibly useful innovative technology, but it is not widely accessible due to the cost of it.
Nat Hardy: Recycling plants in wealthy areas might be able to justify these very efficient sorting systems. But for others, especially in rural areas, this type of investment might not make sense.
Leo Nachamie: So a lot of recycling plants use a combination of machinery and workers that sort materials by hand, which can be dangerous for the people handling glass.
Megan Hall: So how does all of this affect how often glass gets recycled?
Leo Nachamie: Glass that’s contaminated is worth less money. That means it’s less likely to be recycled.
Nat Hardy: And, when cities and towns throw all of their recycling in one bin, it’s harder to sort out the glass – so it’s more likely to get contaminated.
Megan Hall: I get it! So, should we start sorting our recycling into separate bins?
Nat Hardy: Well, it’s hard to say… single stream is popular for a reason. It makes recycling easy for households, and it cuts down on transportation costs since all the recycling goes into one truck.
Leo Nachamie: So communities really have to weigh the transportation costs of multi-stream versus the sorting and contamination costs of single stream.
Megan Hall: Are there any other options?
Nat Hardy: States can pass bottle bills, which put a small deposit on glass bottles. When consumers return their bottles, they get their money back.
Leo Nachamie: This incentivizes people to sort the glass themselves, and those who don’t want to can still participate in regular systems like single-stream.
Megan Hall: Okay, so there are a few different ways we can tackle glass recycling. What’s the big picture?
Nat Hardy: The solution goes back to those two factors we talked about at the beginning. We have to preserve the quality of glass in a cheap way while making it easier for the glass to get recycled.
Leo Nachamie: That might mean introducing bottle bills or switching to multi-stream. But there’s no one size fits all solution.
Megan Hall: Great! Thanks, Leo and Nat!
That’s it for today. You can find more information, or ask a question about the ways your choices affect our planet, at ask possibly dot org. You can also subscribe to Possibly wherever you get your podcasts or follow us on social media at “ask possibly”
Possibly is a co-production of Brown University’s Institute for Environment and Society, Ocean State Media and WBRU.
