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Plastic-eating enzyme could eliminate billions of tons of landfill waste

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Re: Plastic-eating enzyme could eliminate billions of tons of landfill waste

#71

Post by ars »

wang_li wrote: post #43
devops_monkey wrote: post #24

Earlier quoted context omitted.

This is actually the "best" answer for our plastics problem. There was an NPR/Planet Money podcast on it recently here: https://www.npr.org/2020/09/11/912150085/waste-land and there are plenty of other sources that all agree on this premise. I have worked in waste management a few years ago and recycling is not the long-term solution.

Why do we want to put the plastic's carbon into the atmosphere instead of back into the ground where it came from?

Because then we can avoid pumping oil out of the ground and burning that.

The hydrocarbons are going to get burned one way or another, you can just trade one type for another types.

Re: Plastic-eating enzyme could eliminate billions of tons of landfill waste

#72

Post by [deleted] »

323 wrote: post #63

Dumb question, but if plastic eating bacteria starts spreading, wouldn't we all be in a lot of trouble? Will car plastic interior start to rot? Will PET soda and water bottles start decomposing in the grocery store, and will they require refrigeration to prevent that? Will our computer keyboards require new materials?

[deleted]

Re: Plastic-eating enzyme could eliminate billions of tons of landfill waste

#73

Post by google234123 »

noja wrote: post #59
BurningFrog wrote: post #52

Earlier quoted context omitted.

Yeah, landfills are not major environmental problems, AFAIK, but they offend the neat freak within all of us. And, as you say, they're pretty good carbon deposits, which is supposed to be The Most Important Thing.

> Yeah, landfills are not major environmental problems ... yet?

If you are worried about space i recommend that you look at the surface area of earth and the volume of space that’s accessible to us underneath the surface.

Re: Plastic-eating enzyme could eliminate billions of tons of landfill waste

#74

Post by ars »

323 wrote: post #63

Dumb question, but if plastic eating bacteria starts spreading, wouldn't we all be in a lot of trouble? Will car plastic interior start to rot? Will PET soda and water bottles start decomposing in the grocery store, and will they require refrigeration to prevent that? Will our computer keyboards require new materials?

This is for an enzyme, not bacteria, but to answer your question bacteria still need water, so if you keep the plastic dry it should be fine even in such a world.

PET soda bottles will be sterilized, then sealed. The outside is dry and won't decompose. You won't be able to re-close it and leave it out though.

For things that need to stay wet, like drain pipes, you would add chlorine and use PVC which is unlikely to be edible to bacteria.

Re: Plastic-eating enzyme could eliminate billions of tons of landfill waste

#75

Post by faitswulff »

rootusrootus wrote: post #41
faitswulff wrote: post #36

Earlier quoted context omitted.

This could theoretically treat free-floating microplastics in, e.g., the ocean, which you can't plausibly isolate in landfills.

Correct me if I'm wrong, but doesn't this process still assume that the plastic is collected and heated (not super hot, the claim seems to be "less than 50C")? In the case of the ocean, it doesn't seem like this technology would be useful until after we collect all the little bits of plastic. And at that point we could just put it in a landfill anyway.

Yeah, good point. Theoretically, a more optimized enzyme might be able to do it at ambient temperatures, which they mention in the article as a target. Assuming the search space for enzyme mutations isn't already exhausted.

Re: Plastic-eating enzyme could eliminate billions of tons of landfill waste

#77

Post by faitswulff »

abcc8 wrote: post #40
faitswulff wrote: post #25

Earlier quoted context omitted.

Note: the article talks about an enzyme, which is a simple protein. They might manufacture it via organic means, but the enzyme by itself has no capacity to reproduce or mutate.

That is true, but the best and easiest way to make a huge mass of a specific enzyme is to grow it in something, either bacteria or yeast. If it is in an organism, the organism can escape into the wild.

That's a much smaller threat than if the organism itself were to be applied directly to plastics.

Designer organisms aren't generally well-suited to spreading in the wild and even if they were, they could be engineered to require a certain dependency that they would die without. But yes, still theoretically it's possible.

Re: Plastic-eating enzyme could eliminate billions of tons of landfill waste

#78

Post by ars »

r00fus wrote: post #14
tda wrote: post #9

Plastic waste should be burned for heat and/or electricity in an incinerator. Every other usage/disposal method seems like a waste to me. Instead of burning fossil fuels directly, we get much more value from them if we first turn it into some plastic product, and only then burn it. And as long as we keep burning fossil fuels for heat and power, let's not wate out attention on recycling (downcycling actually) plastics…

Doesn't burning plastic produce large amounts of toxic off gassing?

No, they produce water and CO2. Nothing toxic, unless you don't give enough air (so obviously make sure to give enough air).

This isn't some theory - right now, today, lost of plastic is being burned, and it works just fine. They try to keep is off the radar because of misinformed people thinking it's bad.

Re: Plastic-eating enzyme could eliminate billions of tons of landfill waste

#79

Post by DANK_YACHT »

noja wrote: post #59
BurningFrog wrote: post #52

Earlier quoted context omitted.

Yeah, landfills are not major environmental problems, AFAIK, but they offend the neat freak within all of us. And, as you say, they're pretty good carbon deposits, which is supposed to be The Most Important Thing.

> Yeah, landfills are not major environmental problems ... yet?

What would cause them to be an environmental issue? As far as I know they can be built in a safe manner and there is plenty of space for them.
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