Converting plastic back into oil

[Jenn]

Comment: I received this from a knowledgeable friend. One can only hope it is true.
Essentially it is a low cost process from turning plastic into oil.

Check this out. Sound is all in Japanese. Just read the subtitles and watch.

[hambubba]

If it were that easy... You'd think somebody somewhere would have noticed this simple process.

Just watching the video, the amounts don't jog... 1kg = 1 liter? there's no way. I suspect he is burning the plastic, but has some oil stored in the device. Plus, the refinability into different materials is weird.

Oh well, according to this article on wiki, plastic isn't made of "oil". And, it's extremely hard to get rid of - burning is potentially toxic, not just "CO2".

However, you could sell this gadget to lots of little villages, then when the oil gets pumped out of their device, you stop answering the phone... oh wait, they don't have phones...

Scam. No doubt.

[Dropbear]

It is all a bit 'magic box' isn't it? Especially the bit with you don't have to prepare the plastic at all - just jam it in the machine with paper labels etc.

Dropbear

[Alchemy]

The company claims the device works for polyethylene, polypropylene, and polystyrene. In the video it appears he's loading the machine with polystyrene. The company also claims that a 3 hour process will recover about 80% of the plastic mass as oil, which would be consistent with obtaining one liter (0.8 kg) of kerosene from one kg of material.

I don't know anything specific about the instrument; it seems similar (perhaps even identical) to a device patented by DeWhitt for Plas2Fuel (US 7,758,729).

http://www.agilyx.com/home.shtml
http://www.blest.co.jp/index.html

[Alchemy]

Originally Posted by hambubba

If it were that easy... You'd think somebody somewhere would have noticed this simple process.

Several companies have; patents for this sort of thing go back into the late 90's. Really, anything made of carbon you can make into straight-chain hydrocarbons. Coal-to-gasoline processes have been around since the 1930s - it's just a matter of energetic and economic sustainability.

In this process, the claim is that under a particular temperature/pressure combination you can thermally crack the polymer into condensed distillates (i.e. some mix of hydrocarbons spanning the range of gasoline, kerosene, and fuel oil). The patented processes I've seen make it clear that a lot of material that breaks up is vacuum distillates or LPG (which are vapors at room temperature and atmospheric pressure) and this flammable gas is captured and burned to provide heat for the cracking process. This makes sense if there's a set energy cost but a zero (or even negative) material cost. It is acknowledged that there will be contaminants (water, soil, paper, etc.) that need to either remain in the chamber or be captured and separated from the oil - this is part of the purpose of that water chamber.

The somewhat remarkable claim here is ~80% recovery of condensed distillates (C5-C22 or so) from PE, PP, and PS. The viscosity of the recovered oil and the heavy black smoke when it burns would be consistent with fuel oil (~C22). This claim is not so far-fetched in light of similar experimental results - L. Sojáka,, R. Kubineca, H. Jurdákováa, E. Hájekováb, M. Bajusb, GC-MS OF POLYETHYLENE AND POLYPROPYLENE THERMAL CRACKING PRODUCTS, Petroleum & Coal 48 (2006) 1-14; countless articles in the Journal of Analytical and Applied Pyrolysis.

Scam. No doubt.

In the sense that the company might overstate the economics of such a device, perhaps, although it's quite clear they're only selling demonstration models. A device of such small size would not be practical.

My BS meter pinged a bit on this too, but the claims of the device are backed by prior work and publications, so I have every reason to believe it works more or less as described.

[Singing in the Drizzle]

I remember someone round the NW area of the US patenting a way to recycle all plastics by converting them back into oil. This was around the late 80s or early 90s. The problem at that time was that it cost more to convert plastic back into oil that what it cost to buy new oil. Plus the oil was only good for making new plastics with out further processing that would add more expensive to it.

A quick googlefu turned up this
Recycling company converts plastic into oil