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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/ https:/

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/ https://www.quantafuel.com/

userbinator 4y ago
It's pretty close to the same principles a petroleum refinery operates on: https://en.wikipedia.org/wiki/Fluid_catalytic_cracking https://en.wikipedia.org/wiki/Fluid_catalytic_cracking
- PaulHoule 4y ago
  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 describe and produces outputs similar to a petrochemical factory that can be used to make all sorts of things. Both of the above processes are still terribly expensive and environmentally dirty but they are the subject of very active research and they might get practical someday.
  - hinkley 4y ago
    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.
hinkley 4y ago
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.

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/ https://www.quantafuel.com/

userbinator 4y ago

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

PaulHoule 4y ago
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 describe and produces outputs similar to a petrochemical factory that can be used to make all sorts of things. Both of the above processes are still terribly expensive and environmentally dirty but they are the subject of very active research and they might get practical someday.
- hinkley 4y ago
  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.

hinkley 4y ago

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.