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Comment by Reichhardt | Hacker News Reader

Why do we insist on composting or burying so much trash? Let's just burn plastic in the same high-temperature facilities common across Scandinavia. Plastic and packaging use is still only 5% of the oil going up in smoke in engines.

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How is incinerating supposed to be better than burying (not composting)?

Edit: Yes, I obviously understand there's an energy release, but is finding yet another way to burn more oil and get carbon into the atmosphere really what we need at this point in time?

First, there's a lot of energy in the chemical bonds, so depending on how you're incinerating it, you can get some useful energy out of it. The Hefty Energy Bag program does this - they did a lifecycle analysis on various plastic "end of life" paths from "landfill" to "advanced plastic thermal decomposition" to "burn it in a cement kiln" - with the last one working by far, the best. At last per their analysis. If you're offsetting coal use, which is what would otherwise be burned in the cement kiln (I believe natural gas and hydrogen don't emit enough radiation because of their lack of carbons to be as useful), great.

Second, done properly (insert a lot of observations about combustion temperature here), it ends up as nothing worse than CO2, nitrogen, water, etc at the exhaust stack. Given how horribly bioreactive plastics tend to be, and their tendency to erode into microplastics given half an opportunity, this is roughly the "Flare the methane to CO2 because it's far less bad" end of plastic compared to burying it, which, at some point in the future, stands good odds of being uncovered - perhaps by a group that doesn't understand just how nasty the stuff really is.

If your takeaway is "There don't sound like any great ways to deal with plastic," good. Because there aren't.

It prevents the plastics from entering the environment.

Plastics are a material with no effective bio-degredation process so we should destroy it rather than return it to the environment. Otherwise we're just delaying cleanup.

Incineration destroys these unnatural carbon chains and returns the materials to a state usable by natural life.

It's WAY WAY better! The plastic does not accumulate, and you get to use the energy embodied in the plastic, instead of pumping more oil out of the ground.

It's one of those rare win/win things, with no downsides. Of course people won't do it because you have to "recycle" it - which is worse for the environment, but it's an emotional thing, so don't expect people to listen to reason.

+1. Burying plastic (in a place where it's safe to do so) would be a form of carbon sequestration so should be considered a positive.

Carbon sequestration isn't necessarily an end goal that is necessarily worth extra effort, even if this comment made sense beyond that.

Under what logic does "Remove oil from the ground, process it into something, and then bury that something" count as actual carbon sequestration? You've not removed anything from the atmosphere in any plastic cycle I'm aware of, and you've used an awful lot of energy in the process of going from "ground" to "ground." You'd have been better off, in every possible way, just leaving that oil in the ground in the first place.

Except for the important way, which is corporate profits.

I agree but the same logic applies to "remove oil from the ground, burn it, capture the carbon from the smoke using expensive equipment, then bury the smoke" which describes all major carbon sequestration plans if I understand correctly.

I think that both forms of sequestration (sequestering gaseous CO2 (or a solid-stabilized form of it) vs sequestering plastic) are worse than not drilling the oil to begin with, but better than letting the CO2 end up in the air.

Climeworks is doing some work with atmospheric capture and sequestration in basalt via underground water injection (I believe they site with hydroelectric plants which gives them the reinjection well infrastructure mostly for free).

You can do the same thing by grinding basalt and spreading it on fields, which... given that I live on a pile of basalt, might be useful eventually. I keep collecting the stuff to make a greenhouse with, though.

It may be better than leaving it in the air, but given all the other biological activity of plastic, I'd really rather we not use the stuff in the first place at this point.

For one, you can generate electricity. It does produce CO2, however, whereas burying sequesters the carbon.

You get energy out of it instead of wasting that energy.

Plastics are packed with energy. There are already bacteria and fungi taking advantage of that energy source. I think we’ll soon see micro-plastics being “taken care of” by a new ecosystem.

The bacteria will spread like wildfire: the environment is lush with micro-plastics. Things will evolve from there. Perhaps in the future, natural bacterial gene transfers will create plastic-consuming termites.

https://microbewiki.kenyon.edu/index.php/Plastic-eating_Bact...

https://e360.yale.edu/digest/bugs-are-evolving-to-eat-plasti...

Oh, heck, turns out there are plastic-eating caterpillars!

https://www.theatlantic.com/science/archive/2017/04/the-very...

In the dystopian future, we no longer have plastics because it just gets eaten, as useful as building homes from gingerbread.

People are obsessed with "recycling" plastic, instead of doing the right thing and burning it for energy. It's some kind of emotional "I'm not wasting it" thing.

scientists recently found microplastics in rain and human blood… so let’s not burn them unless the exhaust is heavily filtered

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