[CptFribble]

Another story about waste "solutions," another opportunity to remind the gentle readers about plasma gasification. A re-post of an earlier comment of mine on the topic follows:

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Why are we still not talking about plasma gasification? https://en.wikipedia.org/wiki/Plasma_gasification

As far as I can tell, the only real "disadvantages" if you can call them that, are:

1. more expensive than throwing the garbage in a big pile somewhere

2. need to clean it from time to time

3. not necessarily a profitable business

Other than that, it can handle just about anything that's not radioactive, can be designed to produce 0 toxic byproducts, and can run at or at least only slightly below energy neutral. Plasma gasifiers can also consume a huge amount of garbage for their size, so much so that the US Navy is starting to put them on the latest generation of aircraft carriers.

Not building out more gasifiers seems to me a failure of the free market. Because it's hard to make it profitable, no one is doing it - when really we should just be building one or two near every major city and funneling all our garbage there.

In theory, we could build out enough to start working through all the landfills too.

[01100011]

Does plasma gasification result in plastic monomers that can be used as building blocks for new polymers? If not, it seems like it is addressing a different need.

[kragen]

this novel process seems to produce carbon dioxide and water, not terephthalic acid

[PaulDavisThe1st]

ah, CO2 ... we've been looking for a new source of this extremely rare material for some time now, I hear.

[in_vestor]

The most frustrating problem with plasma gasification from my perspective is that it essentially down cycles metals. That is, the metals either end up in slag or as a difficult-to-refine mixture.

That was my understanding the last time I worked on this. I would love to hear about any progress on this.

For what it’s worth, I think the companies that have tried this have not pursued the correct business model. They all either want to sell their system (bad idea) or sell syngas (ok, but not enough). What they need to do is charge tipping fees like a landfill to simply dispose of the trash.

[flavius29663]

I was always thinking, could we combine incineration + plasma gasification? What if we burn the garbage, which results in a lot of heat + clean + noxious gases, and then we just pass the gases through plasma? That should take care of anything that is dangerous in the emissions, but also make it more efficient, because a lot of the mass has already burned, plasma doesn't have to go through that much material anymore

[cma]

Isn't there more mass after burning, from the added oxygen?

[Roritharr]

I'm thinking in the same way, just would love a slimmed down domestic version. The inefficiency of garbage trucks hauling waste around should easily cover the cost of energy for both gasification and the reduction of pollution to acceptable levels.

This would also bring you the added benefit of actually knowing that your waste does not contribute to introducing harmful toxins to groundwater supply or even the sea.

[kragen]

probably because landfills work fine if you aren't on an aircraft carrier. and they're cheaper. they're also rich veins of valuable minerals for the future, but that unfortunately doesn't figure into their present profitability

[bobthepanda]

It's also mentioned that it's more expensive than normal incineration, and waste-to-energy gets you most of the way towards eliminating the worst parts of plastic waste if done right. It's very widespread in Japan and parts of Europe already.

Usually the issue with waste-to-energy is locating a facility, and I would imagine plasma gasification would run into similar NIMBY issues just because people don't like the idea of being next to a large intake facility of garbage, regardless of how bad it is in practice.

[fomine3]

You missed many countries aren't huge unlike the US

[kragen]

do the math instead of posting random bullshit

i did

https://dercuano.github.io/topics/garbage.html

in particular

https://dercuano.github.io/notes/underground-arcology.html#a...

[okl]

Recent article suggests it can be "free" when selling the graphene, hydrogen: https://onlinelibrary.wiley.com/doi/10.1002/adma.202306763