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Plastic to Oil – Produces 80% Oil

blest.co.jp

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Re: Plastic to Oil – Produces 80% Oil

#231

Post by hinkley »

Here's some math:

3.5KWh rough estimate of power requirement (not including embodied energy of device or repairs).

Oil contains 10,000 kWh per cubic meter (1 million ml). 10 million Wh/m^3 = 10 Wh/ml

Device outputs 380ml of oil, so output is 3800 Wh/run. Depending on the fudge factors on the input power this device yields less than 1.1 units of oil per unit of electricity.

Even if they increase the efficiency at scale, this device's entire value seems to be in in removing a waste product, not in generating an input stream. A device that can 'pull' hydrocarbons from the air might actually beat this on the grounds of efficiency for inputs.

Re: Plastic to Oil – Produces 80% Oil

#232

Post by hinkley »

userbinator wrote: post #22

More information here: https://blest.co.jp/eng/faq/ This seems to be intended for PP/PE which is basically a long-chain hydrocarbon anyway, but does make up the bulk of plastic use. It seems to be a very stereotypically Japanese product.

The current wisdom is that PP is one of the least problematic plastics wrt to leachate contaminating the contents. HDPE is also fairly well regarded. In theory LDPE is also considered 'food safe' but if you can smell the plasticizers evaporating off of LDPE (which I absolutely can) then what's it doing to your food?

I read something about PE in the environment recently but I can't recall if it said it was the hardest to break down or the easiest. I'm thinking the former though, since I came away from that article feeling better about PP and worse about PE.

Re: Plastic to Oil – Produces 80% Oil

#233

Post by hinkley »

delijati wrote: post #13

If they do it via "pyrolyse" (burning plastic without oxygen) there is this Quantafuel [1] doing this in "large scale". [1] https://www.quantafuel.com/

SCWO (supercritical water oxidation) is pretty much only used for superfund projects because of the expense of the machinery. It basically burns materials in oxygenated water, turning everything into water, carbon dioxide, and salts/acids.

The salts and acids are a problem that prevents commercial use, because it turns out corrosion, heat, and pressure are the 'pick two' of ceramic materials. Last I read someone was trying to work around this problem by building a heat and pressure optimized vessel and coating it with a corrosion (and?) resistant glazing. I imagine getting the thermal expansion for the two materials to be identical is a right difficult problem.

Re: Plastic to Oil – Produces 80% Oil

#234

Post by soperj »

Retric wrote: post #204
hinkley wrote: post #197

Earlier quoted context omitted.

The dryer abrades the fabric. If you have a delicate or dear piece of clothing they always advise that you air dry it as the fabric will last longer. Those delicate bags for the washing machine are substantially about limiting abrasion from rougher clothing, and also about not accidentally running them through the dryer by tucking inside or clinging to something else.

Normal use also abrades fabrics, the point is normal use doesn’t collect these damaged fibers so they all just end up in the environment.

They end up in the environment regardless. Where do you put your lint trap material? where does the dryer vent to?

Re: Plastic to Oil – Produces 80% Oil

#235

Post by Retric »

hinkley wrote: post #220
Retric wrote: post #188

Earlier quoted context omitted.

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.

I am doing this comparison based on weight not individual items.

It’s really obvious is you’ve ever washed a full load of new clothes vs old clothes.

Re: Plastic to Oil – Produces 80% Oil

#236

Post by Retric »

soperj wrote: post #234
Retric wrote: post #204

Earlier quoted context omitted.

Normal use also abrades fabrics, the point is normal use doesn’t collect these damaged fibers so they all just end up in the environment.

They end up in the environment regardless. Where do you put your lint trap material? where does the dryer vent to?

If you want to be that pedantic the clothes you’re using right now are already part of the environment as are clothes sitting in stores etc.

However, using the common terminology a sealed garbage dump isn’t part of the environment in question because sea life isn’t coming into contact with it.

Re: Plastic to Oil – Produces 80% Oil

#237

Post by hinkley »

PaulHoule wrote: post #38
userbinator wrote: post #24

Earlier quoted context omitted.

It's pretty close to the same principles a petroleum refinery operates on: https://en.wikipedia.org/wiki/Fluid_catalytic_cracking

Ordinary physical recycling of plastics (melt them down) runs into problems because plastics get mixed and mixed with contaminants and because the molecular chains get damaged and break down over time. There are two approaches to chemical recycling. One of them is to reverse the polymerization process and produce the monomer. This can be purified and used to make virgin quality plastic. The other one is like what you…

3) use the best-effort stream of materials to manufacture bulk materials where a small quantity of chemicals that refuse to bond to each other doesn't compromise the product.

Those plastic park benches and decking material products are using a lot of plastic to overcome statistics. But the perverse incentive is that a product that uses a lot of your material per consumer looks much better on paper than it is in real life. Instead of twenty shirts or fifty detergent bottles we made one bench, that goes to the landfill when it's done because it's not cradle-to-cradle.

Re: Plastic to Oil – Produces 80% Oil

#238

Post by ars »

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!

> From a climate perspective, we’d be better to bury the stuff in the ground than to burn it.

Actually from a climate perspective we'd be better off burning the plastic, and reducing how much fresh oil we pump.

I'd rather "bury" if you will, the oil, instead of the plastic.

Re: Plastic to Oil – Produces 80% Oil

#239

Post by CoffeeOnWrite »

leeoniya wrote: post #206
ahmedk92 wrote: post #96

Earlier quoted context omitted.

Before looking, it will probably be more pollution.

there was an infuriating segment on the local news last night that single-use/disposable coffee cups (e.g. keurig) are somehow "greener" because they supposedly use water/energy more efficiently than "traditional" ways of making coffee. of course, zero mention of where these things end up after their 15 seconds of fame. https://wgnradio.com/the-business-of-food-with-steve-alexand... it's like CO2 is the only impact t…

Omg infuriating. Telling me my French press wastes hot water is absurd.

Re: Plastic to Oil – Produces 80% Oil

#240

Post by outworlder »

didericis wrote: post #218
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)

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.
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