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Garbage In, Toxics Out

theintercept.com

1–10 of 25 posts

Re: Garbage In, Toxics Out

#2
I've pretty much given up trying to recycle plastic, and instead throw it in the trash. It's toxic to make (I think?), contaminates food and water when you heat it, and--apparently--can not be recycled safely or efficiently. I realize I can't remove it from life entirely, but I'm actively avoiding it where I can and replacing it as opportunity permits.

Re: Garbage In, Toxics Out

#3
As suspected by many. But we should be grateful for actual reporting on it.

Was this not a problem with the older model of separated recycling (glass, plastic, and paper in separate bins), with plastic limited to numbers 1 and 2 only?

I'm also curious about if plasma gasification is a better option for plastics than whatever this process is.

Re: Garbage In, Toxics Out

#4
This is so disappointing (but not surprising).

Many years ago there was a lot of press about a company call Changing World Technologies (https://en.wikipedia.org/wiki/Changing_World_Technologies) that touted how they could use pyrolysis to convert any hydrocarbon feedstock into fuel (garbage, sewage, etc).

It was going to be cost competitive and clean. Turned out to be not so much when their pilot plant processing turkey remnants stank up the town and shut them down.

The technology seems to be valuable, but it looks like capturing and containing emmissions is still not cost effective so they just dump it.

Re: Garbage In, Toxics Out

#5
post #2

I've pretty much given up trying to recycle plastic, and instead throw it in the trash. It's toxic to make (I think?), contaminates food and water when you heat it, and--apparently--can not be recycled safely or efficiently. I realize I can't remove it from life entirely, but I'm actively avoiding it where I can and replacing it as opportunity permits.

I've heard it said that plastic is better off sequestered in landfills than recycled, to reduce the amount of microplastics getting into the environment.

Re: Garbage In, Toxics Out

#6
I haven't been a chemist in more than 40 years, but even I know that pyrolysis of plastics makes a horrible toxic soup. There is no way to recycle many plastics in this way, the chemistry to reuse this resultant material doesn't exist. All it does is reduce the volume of material, which you then have to put somewhere. Also, the volatiles you generate have to go somewhere, and I highly doubt you want to breath them. You may as well live next to a battery recyling plant that uses coal for energy and raises pigs.

Re: Garbage In, Toxics Out

#7
The problem is with trying to "recycle" garbage plastic. Plastic is mostly carbon, oxygen, and hydrogen. Properly burning it using high-temperature (900+°C) pyrolysis converts most of plastic into water and carbon dioxide. There are some issues with sulfides and nitrogen oxides, but scrubbing those is a familiar problem for the industry. Remaining ash is relatively inert and can be used as a filler in various applications. Releasing carbon dioxide is not great, but it's much safer biologically than polluting environment and oceans with microplastics and total volume is relatively small compared to other emission sources.

Re: Garbage In, Toxics Out

#8
I wonder how they make money. This sounds like grifters living off of government grants. I wonder how widespread the problem is of grifters taking government grants for fake green projects. Perhaps the country made the right move by not doing a green new deal after all. It looks like paying grifters to do science doesn't work very well.

Re: Garbage In, Toxics Out

#9
post #7

The problem is with trying to "recycle" garbage plastic. Plastic is mostly carbon, oxygen, and hydrogen. Properly burning it using high-temperature (900+°C) pyrolysis converts most of plastic into water and carbon dioxide. There are some issues with sulfides and nitrogen oxides, but scrubbing those is a familiar problem for the industry. Remaining ash is relatively inert and can be used as a filler in various applica…

> Properly burning it using high-temperature (900+°C) pyrolysis converts most of plastic into water and carbon dioxide.

I'm a little confused. Isn't pyrolysis what the company said they were doing?

Do they know what pyrolysis is, and are simply lying about doing it, or is pyrolysis a myth?

Re: Garbage In, Toxics Out

#10
post #9
post #7

The problem is with trying to "recycle" garbage plastic. Plastic is mostly carbon, oxygen, and hydrogen. Properly burning it using high-temperature (900+°C) pyrolysis converts most of plastic into water and carbon dioxide. There are some issues with sulfides and nitrogen oxides, but scrubbing those is a familiar problem for the industry. Remaining ash is relatively inert and can be used as a filler in various applica…

> Properly burning it using high-temperature (900+°C) pyrolysis converts most of plastic into water and carbon dioxide. I'm a little confused. Isn't pyrolysis what the company said they were doing? Do they know what pyrolysis is, and are simply lying about doing it, or is pyrolysis a myth?

It's not a myth, it's a basic chemistry and physics. Increase temperature enough and chemical bonds start breaking, transforming complex molecules into simpler ones. Go far enough and you will get bare ionized atoms, i.e. plasma.

But there are different forms of pyrolysis. In my understanding, the company uses lower temperatures to transform plastic into "synthetic oil" (i.e. mix of hydrocarbons instead of long polymer chains), which in theory could be used to synthesize new plastic. Only small part of plastic gets transformed into gas and burned. But this "oil" is much harder to work with than oil pumped from ground, so instead of recycling it fully, some of it gets discarded into environment, resulting in toxic hazard.

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