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hellow0rldz

Breathable micro-plastics doesn't sound nice.

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I thought that’s happening anyways because we burn most of the plastic waste?

In a proper incineration plant it's so hot that there is no microplastics left over

But where does it go then? What’s the chemical reaction? Is there only CO2 and water left then?

Not an expert, but I assume remaining particles are filtered from the exhaust fumes and/or remain part of the remaining sludge.

Pyrolysis seems also like a thing that hopefully becomes viable: https://en.wikipedia.org/wiki/Thermal_depolymerization

Mostly, yeah. Of course polyamides also produce some nitrogen compounds and PVC also produces HCl that you have to deal with, etc.

But generally, plastics are very complex long-chain carbohydrates. Burning them at low temperatures produces all kinds of partially combusted horrible byproducts, but properly incinerating them results in just water and CO2.

I visited an incineration plan once and they showed how the make really sure the temperature is over 900 degrees Celsius st all times so that plastics and biological toxins are properly destroyed.

They also make sure there is lots of air available to the combustion process and thats done in an interesting way. They draw it in via the waste storage bunker solving two issues at once - the stinky air from all the waste gets effectively burned and the bunker is kept as negative air pressure so the smell doesn't get out.

And of course all the exhaust gases pass via a sophisticated fikter plant.

Aren't we then shooting ourselves in the foot then by being scared of burning trash/plastic waste? As an interim before solving all plastic waste, it seems like a much better solution than just stacking plastic into giant dumps.

You have to capture the CO2 and then figure out how to store it or turn it into pure Carbon and then you still have to landfill that.

Maybe. The CO2 going to the atmosphere is not great. You have to way that against the risks of plastic pollution from land filling.

If you are burning any fossil fuels for power, starting up waste incineration power plants to replace them is a pure win.

Perhaps burning trash would be the better solution. But it seems fairly unpopular with people in general, at least in the U.S. - you can imagine how easy it is to generate violent opposition to put a trash-burning facility in any place.

An acquaintance of mine from high school for some reason devoted much of his life to promoting trash burning technology. It seems like a good cause, but a futile one.

Trash incineration plants (referred to as “waste-to-energy” which sounds like an accurate euphemism to me) definitely generate very strong negative reactions in the U.S. I used to live just a couple miles away from one in Syracuse NY and I thought it was a great idea... recycle and reuse what you can, and everything else gets cleanly incinerated and generates electricity at the same time. There was no detectable smell either. Being supportive of the plant definitely put me in the minority based on all the negative feedback I read online and in the local newspaper.

I think burning PVC can produce dioxin, which would be very bad if it's not filtered out from the exhaust. Then it depends on how much you trust the facility to have an effective filter installed, and test and maintain it diligently. That costs money, so there will be a tendency to skip the maintenance.

No. Only partial combustion of PVC produces dioxins. Proper incineration plants do not produce any. So the solution is not filters, but hotter combustion.

Some countries have made that decision. For instance, Sweden recycles roughly half of all household waste, and burns almost all the rest.

https://www.nytimes.com/2018/09/21/climate/sweden-garbage-us...

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