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Comment by ars | Hacker News Reader

Even smarter would be to take that plastic and burn it for energy, instead of giving that energy to an enzyme, that will just make waste heat.

After reading the article instead of the headline:

They imply they can turn the plastic back into a monomer and then rebuild it as a new polymer. Maybe that would work, but I have huge doubts - a monomer is very chemically active, and it really wants to polymerize. That enzyme may work in a lab, but I doubt they can turn it into an industrial process.

I take issue with this:

"The most common method for disposing of plastic, besides throwing it in a landfill, is to burn it, which is costly, energy intensive and spews noxious gas into the air."

This is utterly false, and I don't see how they can claim to be scientific if they publish falsehoods. It makes me wonder about the accuracy of the rest of the press release.

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Which part is false? There is at least one part of that statement that is absolutely true.

The only part that is true is that burning is the most common method, with recycling being a close third.

> which is costly

Burning is not costly it is cheaper than all other methods. It's so cheap it's actually profitable.

> energy intensive

It actually provides extra energy, and reduces energy waste (because now we have to pump less oil.)

> and spews noxious gas into the air.

It spews nothing except water and CO2.

I wouldn't exactly call it noxious, but C02 isn't exactly something we want to be spewing more of. Isn't a landfill full of plastic pretty much just a big pile of captured carbon?

It's captured oil basically, not captured CO2. (Don't say "captured carbon", when you mean "captured co2", because it leads to confusion - do you mean burned or unburned carbon?)

And since we are still pumping oil of the ground, leaving a different form of oil (plastic) in the ground doesn't accomplish anything useful.

>do you mean burned or unburned carbon?

I'm not sure what distinction you're trying to draw.

>And since we are still pumping oil of the ground, leaving a different form of oil (plastic) in the ground doesn't accomplish anything useful.

I suspect that overall energy production in the US probably emits less CO2 per kwhr than burning garbage does, so starting to burn garbage for energy would be, in that regard, a net negative. Furthermore, it would likely require moderately significant capital expenditure that could've instead been used for something better.

Yeah, no.

It spews NOx and the whole bunch of undesirable things like dioxines.

You don't get pure PET and oxygen in, and you don't get pure CO2+H2O out.

It's messy to the point that it's debatable if it's better just to bury it.

Why would you have NOx? The fire is not that hot. And no, there are no dioxines because they burn up in the fire.

> It's messy to the point that it's debatable if it's better just to bury it.

No, it's not. You do get that people are doing this already, right now? It's not some theoretical - there's a huge amount of plastics being burned, and it's very clean.

https://no-burn.org and others.. incinerator waste to energy has been a battle for at least fifty years..

Another organization we can blame for terrible environmental outcomes?

Why is it so common for people to pretend to be environmentalists and advocate for things that directly harm the environment?

> we can blame for terrible environmental outcomes

who is "we" here ?

> to pretend to be environmentalists

that is wildly defamatory, with no evidence, right?

We is you and me.

> that is wildly defamatory, with no evidence, right?

The evidence is right on their own website. Their advocacy that they are so proud of is actively harming the planet and they are sitting there proud of it.

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.

Industrial waste incineration is not at all the same thing as burning trash in a backyard fire.

I recall throwing some plastic bottlecaps in fireplaces during my youth. IIRC, they'd get melty, then the puddle would ignite and burn very hot, until it was spent, and that would be about it. Might have smelled funny, but I can't remember that far back; was less sooty than the wood at least. Of course, water bottle caps aren't likely to have food waste or much of anything else other than the plastic, maybe a smidge of water and some fingeroils from handling. I also didn't have a gas spectrometer or anything, and the fireplace wasn't an industrial furnace with process controls and what not.

On the topic of food waste, my time in the kitchen says most foods will burn just fine. Although, they often leave residues that I could see being problematic when they build up.

As with everything, you'd need specifics to determine the right tradeoffs. It would seem to me there's potential in reducing the transport distance and land use of solid waste, and also reducing extraction, transport, and burning of some fossil fuels, if a burn the trash for electricity program works. But specifics matter, of course.

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