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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

#51

Post by noizejoy »

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…

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

And IMO there’s much upside to pursue multiple avenues to desired solutions, rather than making choices to eliminate potentially contending solutions too early.

Mother nature herself provides pretty much exactly that template for evolution. So if we want to save nature, why not use that same approach? It seems to have served the survival of life on our planet rather well.

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

#52

Post by BurningFrog »

not2b wrote: post #44

Depends on what the waste products are and how they are captured, otherwise you trade one problem for another. The plastic takes up space but if it's in a landfill you have carbon capture, best not to release that carbon into the air as CH4 or CO2.

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.

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

#53

Post by sschueller »

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…

We should be focusing on reducing trash and getting raw materials back out of trash. The rest should be burned or processed cleanly and maybe generate electricity while at it.

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

#55

Post by ars »

kube-system wrote: post #18
ars wrote: post #8

Earlier quoted context omitted.

Exactly. Everyone thinks there will be black smoke, but actually plastic burns very clean in a proper incinerator.

They're dirtier than natural gas power plants, however. (and the pollution that they do create can be particularly nasty) We're better off in terms of emissions-per-watt by burying the plastic and using natural gas instead.

> They're dirtier than natural gas power plants, however

That is not true.

> and the pollution that they do create can be particularly nasty

That is also not true.

Plastic is made of the exact same atoms as natural gas, plus oxygen. Plastic burns very very clean, with no waste except for water and CO2.

PVC has chlorine, but is rare in trash, and the small amount of chlorine is easily filtered out of the exhaust.

> We're better off in terms of emissions-per-watt by burying the plastic and using natural gas instead.

This is also not true because it costs energy to extract the natural gas. The plastic is already there, and needs to be dealt with one way or another. Plastic makes about the same CO2/watt as gasoline.

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

#56

Post by tda »

mistrial9 wrote: post #45
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…

this is widely promoted (incinerator to energy) and widely disliked (state of the air in industrial locations around the world) .. not a new idea

I think just about all household trash in the Netherlands is incinerated. And as far as I know the exhoust fumes are manageable, but definitely not something to live next to. Just like any other fossil fuel run powerplant by the way.

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

#57

Post by ars »

williamtwild wrote: post #27
r00fus wrote: post #21

Earlier quoted context omitted.

Isn't the problem with plastic burning the fact that most plastic waste is actually contaminated with food/non-plastics that burn differently?

Yes. I see quite a few three letter accounts advocating for burning plastic. Let them throw some in their fireplace of the chimnea while relaxing with the family and see how that goes.

PET burns very clean with enough air. I use it as a fire starter for outdoor fires.

A fireplace is a smoky thing, without enough air (even the wood makes a lot of smoke). An incinerator makes sure to supply enough air.

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

#58

Post by lkbm »

not2b wrote: post #44

Depends on what the waste products are and how they are captured, otherwise you trade one problem for another. The plastic takes up space but if it's in a landfill you have carbon capture, best not to release that carbon into the air as CH4 or CO2.

The article talks about using it for environmental cleanup, but the paper seems more focused on recycling back into fresh PET[0]:

> ...and a circular carbon economy for PET is theoretically attainable through rapid enzymatic depolymerization followed by repolymerization or conversion/valorization into other products

> Finally, we demonstrate a closed-loop PET recycling process by using FAST-PETase and resynthesizing PET from the recovered monomers. Collectively, our results demonstrate a viable route for enzymatic plastic recycling at the industrial scale.

[0] https://www.nature.com/articles/s41586-022-04599-z

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

#59

Post by noja »

BurningFrog wrote: post #52
not2b wrote: post #44

Depends on what the waste products are and how they are captured, otherwise you trade one problem for another. The plastic takes up space but if it's in a landfill you have carbon capture, best not to release that carbon into the air as CH4 or CO2.

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?

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