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Plastic to Oil – Produces 80% Oil

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Re: Plastic to Oil – Produces 80% Oil

#211

Post by gonzoflip »

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-...

Yeah, water/meth injection is pretty common mod for forced induction cars to squeeze some more air in there without causing detonation. People often just tap the windshield washer reservoir and use that to hold the meth, since windshield wiper fluid is a more diluted methanol mix you can still use it for your windshield. I personally don't run it because running out of meth on a vehicle that is tuned for it can have disastrous consequences.

Re: Plastic to Oil – Produces 80% Oil

#212

Post by diyseguy »

colordrops wrote: post #193
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's only cheaper because externalities are ignored. If we had proper legislation that took environmental externalities into account, it might not be cheaper anymore.

Yes, couldn't they just make some government subsidies to incentivize it? Then we could be rid of all the nasty plastic waste that keeps finding it's way into the ocean and everywhere else?

Re: Plastic to Oil – Produces 80% Oil

#213

Post by yowlingcat »

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!

Are you suggesting to bury it in the ground so it can leach into groundwater and soil rather than even trying to capture and reuse the CO2? Are you serious or are you joking?

Re: Plastic to Oil – Produces 80% Oil

#214

Post by throwaway5959 »

godelski wrote: post #208
HackOfAllTrades wrote: post #201

Why do people keep falling for this? This same fraud used to pop up only every 10 years. Now it's 5 or less. I'm a PhD chemist. Please consider this: While plastics and oil are both hydrocarbons they have this important difference. Liquid hydrocarbons have short carbon chains and lots of hydrogen. Plastics have very LONG carbon chains, usually with many double bonds, and very little hydrogen. That is why, when you he…

Is it hard to add a source of hydrogen? In the images they have here it looks like there is a vat of water and it explicitly says it produces H2O and CO2 gas waste (though calls the CO2 harmless). That would imply there is a source of hydrogen here. (Not an expert, just legitimately curious so I can better spot snake oil)

At that point, why not just use hydrogen as a fuel? Or better yet, just use batteries.

Re: Plastic to Oil – Produces 80% Oil

#215

Post by lesuorac »

ac29 wrote: post #177
lesuorac wrote: post #114

Earlier quoted context omitted.

You can still burry the soot after you burned the plastic.

Most of the carbon is going to end up as CO2 in the air, though.

You don't need to burn it in an open field ...

You can used a closed system so that the waste is actually all captured. Or you can have a more continuous system that'll capture/scrub the output.

Re: Plastic to Oil – Produces 80% Oil

#216

Post by arbitrage »

throwaway5959 wrote: post #214
godelski wrote: post #208

Earlier quoted context omitted.

Is it hard to add a source of hydrogen? In the images they have here it looks like there is a vat of water and it explicitly says it produces H2O and CO2 gas waste (though calls the CO2 harmless). That would imply there is a source of hydrogen here. (Not an expert, just legitimately curious so I can better spot snake oil)

At that point, why not just use hydrogen as a fuel? Or better yet, just use batteries.

I can't fuel my car with hydrogen.

Re: Plastic to Oil – Produces 80% Oil

#217

Post by missedthecue »

csours wrote: post #160
manbitesdog wrote: post #82

"This sounds too cool, let's check HN comments for the disappointment"

If you wanted to burn plastic for energy, you can already do it at a electrical generation plant. You have to put more energy in to get oil out. Um. And climate change.

Not all energy is created equal though. There are applications where 1kwh of oil is more valuable than 1kwh of electricity.

Re: Plastic to Oil – Produces 80% Oil

#218

Post by didericis »

godelski wrote: post #208
HackOfAllTrades wrote: post #201

Why do people keep falling for this? This same fraud used to pop up only every 10 years. Now it's 5 or less. I'm a PhD chemist. Please consider this: While plastics and oil are both hydrocarbons they have this important difference. Liquid hydrocarbons have short carbon chains and lots of hydrogen. Plastics have very LONG carbon chains, usually with many double bonds, and very little hydrogen. That is why, when you he…

Is it hard to add a source of hydrogen? In the images they have here it looks like there is a vat of water and it explicitly says it produces H2O and CO2 gas waste (though calls the CO2 harmless). That would imply there is a source of hydrogen here. (Not an expert, just legitimately curious so I can better spot snake oil)

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 as well, but if it is possible I’m sure it’d be astronomically energy intensive and wasteful to manipulate matter to that degree)

Re: Plastic to Oil – Produces 80% Oil

#220

Post by hinkley »

Retric wrote: post #188
hunter2_ wrote: post #183

Earlier quoted context omitted.

Isn't it possible that tumbling is the only significant source of breakage?

If that was the case old clothes would produces far more lint in a dryer because the dryer would keep damaging them. Instead the reverse happens with new clothes produces vastly more and it tappers off. They do cause damage, but it isn’t the overwhelming source of damage.

Old clothes have a lot less fiber in them. Whether your math checks out would depend on the % of fibers lost per week rather than just the total number.

Washing machines also have lint traps, and the water treatment plant has to deal with a lot of solids from washing machines. I don't have numbers on what percent comes out in that case.

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