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Continuous System For Converting Waste Plastics Into Crude Oil
rtoz writes: A MIT spinout company aims to end the landfilling of plastic with a cost-effective system that breaks down nonrecycled plastics into oil, while reusing some of the gas it produces to operate. To convert the plastics into oil, this new system first shreds them. The shreds are then entered into a reactor — which runs at about 400 degrees Celsius — where a catalyst helps degrade the plastics' long carbon chains. This produces a vapor that runs through a condenser, where it's made into oil. Much of the system's innovation is in its continuous operation (video). This company aims to produce more refined fuel that recyclers can immediately pump back into their recycling trucks, without the need for oil refineries. Currently, 2 trillion tons of plastic waste is sitting in U.S. landfills, so there is a huge demand for this technology.
Why even bother with the landfills? There are massive garbage patches floating around in the oceans, the vast majority of which are plastics. If you can get a big enough tanker and implement this system on it, you could probably cut the amount of fuel needed even further - the tanker goes into a garbage patch, melts all the plastic down, keeps the oil, and uses some of it to get back to land. It would probably be more effective than loading fleets of trucks.
I'm all for eliminating waste, but if the net effect is that we're removing plastic from landfills and emitting it as CO2, that's not terribly different from digging up crude oil and emitting it as CO2.
Now, I'm sure there's some sort of multiplier here that makes it a bit better - perhaps the plastics are a cleaner source and less energy will be used to process it - but currently this carbon is sequestered in an inert if unattractive form whose dangers are mostly localized.
While this converts waste plastic to oil it does not however:
A.: complete this conversion at a less than or equal cost of energy generated by the oil. The shredder, crucible, and condenser arent powered by the mellow rock stylings of huey lewis and the news.
B.: Absolve us from researching alternatives to crude oil, a fossil fuel that is finite in supply and directly contributing to climate change.
Our lust for oil has become all but indistinguishable from a heroin addicts search for a fix.
Good people go to bed earlier.
While I totally agree with this, I think it misses the point.
Assuming that plastic is provided for free (cities or landfills are already pulling plastic out via a separation step) then enough energy can be *recovered* from the plastic to power the recovery process with a net gain. The goal is not energy independence... it's prevention of non-biodegradable items making it into the landfill.
There was a story a few months ago about an MIT project to float a collector out into the ocean to pick up plastic... maybe these two teams should get together.
Which has more power: the hammer, or the anvil?
It's not the point. The point is to take a material that does nothing and to make it useful again. There's only so much plastic you can convert back into carpet and other non critical product. If this isn't BS and the result of the transformation is more fuel than what was used then it's a no brainer. The technology will be adopted and improved which will have even bigger ROI.
Currently we pay to get rid of plastic. This allows making plastic disposal lucrative and that in my books is a positive ROI.
The statement that there is 2 trillion tons of plastic in land fills got me wondering how much oil actually goes into producing something. From what I can gather a barrel of oil weighs about 300 pounds so if there aren't any other external inputs into making plastics that would mean that about 13 trillion barrels of oil have been turned into plastic. This doesn't seem the least bit right given that under 2 trillion barrels of oil have been extracted and not all of that went into making plastic. So how much oil actually goes into making plastic and how much is other stuff is use?
This leads me to my next question which is how much of the weight of the plastic is turned into oil? If it is over 1/6 of it then we have the equivalent of more than all presently extracted oil in our land fills already.
Time to offend someone
Pyrolysis for "recycling" plastic waste into oil (or tire waste into oil) has been around since at least the 1990s. The main problems are 2: A) As Irate Engineer states, a polymer is an "added value" and deconstructing polymers back to oil always fails economically when actual recycling to like-polymers is available, and B) as Itzy says, the comparative value of returning it to fuel, vs. leaving it in an Municipal Solid Waste to energy facility and burning it, is small.
I read TFA and cannot figure out what differentiates this from the pyrolysis "waste investments" of the 1990s, none of which really sailed.
Gently reply