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Plastic to Oil – Produces 80% Oil

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Re: Plastic to Oil – Produces 80% Oil

#251

Post by folmar »

ansible wrote: post #185
csours wrote: post #164

Earlier quoted context omitted.

Just like the "water carburetor" and other miracles that never materialized, the problem is that the alternative is cheaper and simpler (which means cheaper). It doesn't sound expensive to add water injection to an internal combustion engine, until you have to make it work in production, with end users. YOU can make it work, because you are motivated, but what about the guy who buys it because it's cool and then forg…

> It doesn't sound expensive to add water injection to an internal combustion engine, until you have to make it work in production, with end users. Water / methanol injection was commonly used on various piston engine aircraft in the 1940's. It had several benefits, cooling the input air, preventing pre-detonation at high compression (due to lower octane fuel in some cases), lowering the combustion temperature, and s…

It _is_ practical for cars, but a similar technology is easier and better: Exhaust Gas Recirculation.

The problem of water injection is engine corrosion and system maintenance. EGR further improves the exhaust gas composition by burning the CO and similar not fully oxidized parts. The main effect is the same, i.e. providing some inert material that expands after detonation using up the heat.

Re: Plastic to Oil – Produces 80% Oil

#252

Post by 40yearoldman »

outworlder wrote: post #240
didericis wrote: post #218

Earlier quoted context omitted.

https://youtu.be/Zmtc22uPLd4 I’m not a chemist/someone else can offer a more detailed explanation (just love the excuse to post that song), but with most of these kinds of things the energy and advanced equipment required to go in a theoretically plausible direction for a minuscule amount of yield is usually absurd. Including turning iron into gold. (I think it might theoretically be possible to do that at this point…

Turning iron to gold is not possible as a chemical reaction. They are elements. You need a nuclear reaction.

Ahh! So it is possible, just need a nuclear reaction!

Re: Plastic to Oil – Produces 80% Oil

#253

Post by fomine3 »

csours wrote: post #191
ansible wrote: post #185

Earlier quoted context omitted.

> It doesn't sound expensive to add water injection to an internal combustion engine, until you have to make it work in production, with end users. Water / methanol injection was commonly used on various piston engine aircraft in the 1940's. It had several benefits, cooling the input air, preventing pre-detonation at high compression (due to lower octane fuel in some cases), lowering the combustion temperature, and s…

It was also available on early jet aircraft (and may still be used by some). Here's an interesting discussion: https://aviation.stackexchange.com/questions/36185/how-does-... Some people do modify their vehicles for water injection, and at least one recent production car has it: https://www.caranddriver.com/news/a15340747/new-porsche-911-...

two https://www.bmw-m.com/en/topics/magazine-article-pool/5-litr...

Re: Plastic to Oil – Produces 80% Oil

#254

Post by trompetenaccoun »

40yearoldman wrote: post #252
outworlder wrote: post #240

Earlier quoted context omitted.

Turning iron to gold is not possible as a chemical reaction. They are elements. You need a nuclear reaction.

Ahh! So it is possible, just need a nuclear reaction!

It's quite simple: Gather a sufficient amount of iron (4 million times earth's mass will probably do). Bring it all in one place, it will naturally compact. Wait for the resulting supernova - you do want to keep your distance for this step. Lastly collect gold and other heavy elements.

Re: Plastic to Oil – Produces 80% Oil

#255

Post by fomine3 »

cassepipe wrote: post #79
elil17 wrote: post #69

Earlier quoted context omitted.

It happens in waste-to-energy power plants (a.k.a garbage power plants). They can be a great way to get rid of waste but they require a lot of filtering of the exhaust to be safe. Adequate filtering is universal in some countries (like Sweden). In the USA, waste-to-energy plants frequently have inadequate filtering, which can make them dirtier than coal plants.

Do you know if they have to reach a certain temperature ? I would think so because I assumme garbage produces a lot of fumes and gases that would better off burned for energy rather that ending in the air. On the other end I wonder what kind of temperature you can get with a dumpster fire

Incinerators in Japan must be above 800C to avoid generating toxic materials like dioxins. https://www.env.go.jp/content/900453393.pdf

Re: Plastic to Oil – Produces 80% Oil

#256

Post by fomine3 »

actionfromafar wrote: post #47
eloff wrote: post #19

Earlier quoted context omitted.

You could probably use it in a diesel engine. People filter used frying oil from restaurants and run their diesels on that.

Yes, you absolutely can, especially in an old diesel engine, they can run on all kinds of oil. But the engine might not fare well, depending on the properties of the oil, and the exhaust might contain "interesting" stuff like dioxins, depending on what was in the mystery plastic to begin with.

Also old diesel engines are bad for air quality and efficiency

Re: Plastic to Oil – Produces 80% Oil

#257

Post by defrost »

fomine3 wrote: post #256
actionfromafar wrote: post #47

Earlier quoted context omitted.

Yes, you absolutely can, especially in an old diesel engine, they can run on all kinds of oil. But the engine might not fare well, depending on the properties of the oil, and the exhaust might contain "interesting" stuff like dioxins, depending on what was in the mystery plastic to begin with.

Also old diesel engines are bad for air quality and efficiency

There's an argument to be made here for refurbing the best of the container ship engines after the ship hulls reach end of life.

The higher end engines are three storey high multistaged diesel engines with filters, scrubbers and some of the highest bunker oil -> power efficiencies on the planet.

They're ideal for generating baseload power and worth the rejuvenation effort.

Re: Plastic to Oil – Produces 80% Oil

#258

Post by trompetenaccoun »

zwkrt wrote: post #210
aeroblade wrote: post #209

Earlier quoted context omitted.

You know, before tossing around your "PhD" in Chemistry maybe it'd be good to be sure you know what you're talking about first... https://www.frontiersin.org/articles/10.3389/fenrg.2019.0002... ) https://cen.acs.org/environment/recycling/Amid-controversy-i... https://www.sciencedirect.com/science/article/abs/pii/S01652...

I don't know if you meant to, but all three of those links are hilarious if you read them. The first one has `moving toward` in the title, which is academic speak for "it doesn't work and we don't know how to make it work". Otherwise it would be arrived at. Very similar to Betteridge's Law of Headlines for academia. The second link is a news article that is very critical about the motivations, projected success, and…

https://sci-hub.st/https://doi.org/10.1016/j.jaap.2020.10480...

I found this link while searching the DOI of the third article. Sci-Hub seems to be a site that lets you access all sorts of scientific papers, because they believe everyone rich or poor should have free access to science. It was created by Alexandra Elbakyan, a modern day Robin Hood.

Or so they say, I'd never endorse you reading the paper without giving more money to the multi-billion dollar private publisher Elsevier.

Re: Plastic to Oil – Produces 80% Oil

#259

Post by outworlder »

trompetenaccoun wrote: post #254
40yearoldman wrote: post #252

Earlier quoted context omitted.

Ahh! So it is possible, just need a nuclear reaction!

It's quite simple: Gather a sufficient amount of iron (4 million times earth's mass will probably do). Bring it all in one place, it will naturally compact. Wait for the resulting supernova - you do want to keep your distance for this step. Lastly collect gold and other heavy elements.

Yeah. It's even better since you are starting with iron, don't have to wait billions of years for everything to burn first.

Re: Plastic to Oil – Produces 80% Oil

#260

Post by trompetenaccoun »

Reason077 wrote: post #199
8note wrote: post #190

Earlier quoted context omitted.

Burning plastic however, has high temperature requirements to avoid giving off toxic fumes in the smoke, which I think you would reduce by doing a conversion to oil first.

Waste-to-energy plants are designed to reach those high temperatures, amongst other measures, to minimise and prevent toxic emissions. They still produce a lot of CO2, though: plastic is still a fossil fuel. From a climate perspective, we’d be better to bury the stuff in the ground than to burn it. And ideally, we’d just produce a lot less plastic in the first place!

At the point where the plastic is already produced it's the exact opposite. It makes more sense to burn it and reduce our fossil fuel consumption. There may be edge cases where it's debatable, like in Iceland which already runs on 100% renewables.

Btw all these processes aren't as simple. For example decomposing polyethylene produces methane which can leak into the atmosphere where it's one of the worst greenhouse gases of all. If you burn it you "only" produce CO2, which is much preferable. The oil and gas was (semi)-permanently trapped before humans started digging it up without knowing the consequences. Putting waste into a surface dump and covering it with a few meters of soil and maybe some plastic sheets is not the same thing at all. This is not permanent carbon sequestration.

Everyone should consider there are many things we do not understand. In the media we're often presented "experts" who purport to know it all, but it's not true. And many laypeople have strong opinions despite understanding even less.

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