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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

#31

Post by netizen-936824 »

abcc8 wrote: post #19
powerbroker wrote: post #11

I understand that the pits, that are the foundation of landfills, are lined with impermeable plastic sheets. Their purpose is to avoid ground-water contamination. So, there may be some redesign of landfills required before this technology can succeed.

I was thinking the same. Worst case scenario with a solution like this one is that these organisms get into the wild, gain more mutations, and then rapidly release a large volume of carbon, currently sequestered as plastic, into the atmosphere. Or, plastic-tropic organisms used as a weapon, sprayed over cities, etc.

Did I miss something? What organism are you referring to?

An enzyme is a protein not an organism

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

#32

Post by devops_monkey »

MetaWhirledPeas wrote: post #26
williamtwild wrote: post #20

Earlier quoted context omitted.

Yes , it does. Burning plastic without somehow accounting for that is a terrible idea.

Is there a way to mitigate this, or make use of the waste gasses?

See my other comment as well as this HN thread: https://news.ycombinator.com/item?id=20551946

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

#33

Post by Nydhal »

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?

My understanding is that incinerators don't just release the output. The exhaust is pumped back into the system and dealt with somehow. The extent to which the release is "dealt with" is the tricky part.

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

#34

Post by rootusrootus »

Can't help but wonder if this is a solution searching for a problem. Landfills already have protections against leeching into the surrounding environment. And we aren't going to plausibly run out of space for landfills in the foreseeable future (images from Wall-E notwithstanding). Isn't plastic basically inert once it gets to a landfill anyway? Even if it takes centuries to break down, who cares?

IMO we'd be better off focusing research on reducing the waste rather than improving disposal.

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

#35

Post by coryrc »

powerbroker wrote: post #11

I understand that the pits, that are the foundation of landfills, are lined with impermeable plastic sheets. Their purpose is to avoid ground-water contamination. So, there may be some redesign of landfills required before this technology can succeed.

I thought it's usually just natural clay, but I bet it varies based on local conditions.

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

#36

Post by faitswulff »

rootusrootus wrote: post #34

Can't help but wonder if this is a solution searching for a problem. Landfills already have protections against leeching into the surrounding environment. And we aren't going to plausibly run out of space for landfills in the foreseeable future (images from Wall-E notwithstanding). Isn't plastic basically inert once it gets to a landfill anyway? Even if it takes centuries to break down, who cares? IMO we'd be better…

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

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

#37

Post by hh3k0 »

scohesc wrote: post #15

I wonder what the potential harm to infrastructure would be if this bacteria were to escape landfills / remediation sites and happen to get into places where PET is used in something important. Not that I'm against finding ways to _actually_ recycle or break-down plastics, just it seems like something we need a microscope to see might be hard to keep track of.

> I wonder what the potential harm to infrastructure would be if this bacteria were to escape landfills

At the very least, I'm sure it won't be as bad as in BioMeat: Nectar.

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

#38

Post by seoaeu »

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…

Whether we should burn, recycle, or dump plastic into a landfill depends entirely on the relative amount of energy generated and CO2 emitted by those different options. Just because plastic and natural gas both are/come from hydrocarbons doesn’t mean that burning them produces anywhere near the same amount of emissions per MWh, or that the economics would be at all close.

And if you are proposing the construction of new power plants to burn trash, your justification also has to explain why that would be preferable to building wind/solar instead

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

#39

Post by bitwize »

abcc8 wrote: post #19
powerbroker wrote: post #11

I understand that the pits, that are the foundation of landfills, are lined with impermeable plastic sheets. Their purpose is to avoid ground-water contamination. So, there may be some redesign of landfills required before this technology can succeed.

I was thinking the same. Worst case scenario with a solution like this one is that these organisms get into the wild, gain more mutations, and then rapidly release a large volume of carbon, currently sequestered as plastic, into the atmosphere. Or, plastic-tropic organisms used as a weapon, sprayed over cities, etc.

An enzyme is a protein molecule, not a living thing. Probably the biggest risk is that some wildlife or fish may be allergic to it.

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

#40

Post by abcc8 »

faitswulff wrote: post #25
abcc8 wrote: post #19

Earlier quoted context omitted.

I was thinking the same. Worst case scenario with a solution like this one is that these organisms get into the wild, gain more mutations, and then rapidly release a large volume of carbon, currently sequestered as plastic, into the atmosphere. Or, plastic-tropic organisms used as a weapon, sprayed over cities, etc.

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.
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