Plastic waste and tyres?

Discussion in 'The Science Forum' started by BIPOLAR77, Apr 19, 2012.

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  1. the_boy_syrup

    the_boy_syrup LE Book Reviewer

    I would suggest it's not as easy as they are suggesting.
    Tyres are the one problem everyone has when running recycling or scrap yards.
    You can chip them and use them for playgrounds and horse stables but if it was that easy to make diesel everyone would be at it.
    Plus the VAT man would be all over you for his cut they're not going to let you knock out fuel for free.

    If you buy it let me know I've a mate sitting on 100,000 baled tyres.
    Let you have them cheap.
     
    • Like Like x 1
  2. Aye but what about the costs of shipping from the States? availibility of spares and servicing? Not to mention the government slapping some tax on the stuff?
     
  3. Sounds as though it could be a Nigerian Scam to me.
     
  4. I heard about some gippoes who rented a big mill in the north east.

    They were advertising to dispose of scrap tires at a knockdown price.

    When the mill was full to the ceilings with scrap tires..... the gippoes vanished.
     
  5. Scrap tyres are a toxic nightmare. especially when they burn.
     
  6. scaryspice

    scaryspice LE Moderator

    I think you might find the licensing requirements to run such a plant in the UK are a tad different from the US. Backyard recycling isn't quite so easy here...
     
    • Like Like x 1
  7. Maybe not, but if the tyres are torched by accident or arson it would be an environmental disaster.
     
  8. true but you could say that about any kwik fit or scrap yard
     
  9. Yes. That is why scrap yards have to be licensed. You do realise that tyres contain wire as well dont you?
     
  10. how dumb are you?

    If you read the link you will see what by products there are, carbon and metal wire
     
  11. There's gotta be a market for used condoms here.
     
    • Like Like x 2
  12. I investigated a similar technology when trying to think of ways to improve FOB sustainability.

    First off I am a bit sceptical about the first website you provided, and will second Fox-and-horses that it looks like a Nigerian scam.

    The chemical structure of vulcanised rubber is complex and contains, amongst other things, sulphur (as part of the vulcanisation process). That sulphur must go somewhere and even if we suspend disbelief for a moment and say the process does convert old tyres into diesel, the diesel will be sulphur rich and will start corroding your engine, catalytic converter & exhaust.

    Secondly rubber is a complex biopolymer; diesel consists mostly of carbon chains 8 - 21 carbon atoms long. Frankly I would be surprised if thermal decomposition of tyres would result in a 90-95% diesel yield. It is a bit like saying if you put some PE4 in a house and blow it up, 90-95% of the debris would consist of bricks connected in blocks of (say) 4 - 10 units. The most likely result is that you'd get a mixture of organic molecules by pyrolysis of rubber, and you'd have to fractionally distill that to get diesel.

    Thirdly, following on from #2, this is the reason why thermal gasification plants for converting plastics into hydrogen or carbon monoxide work. Going back to the PE4/house example, while you can not end up with blocks of bricks 4-10 units long, put enough PE4 into it and you can end up with lots of tiny bits. Same principle - put enough energy into the pyrolysis process and you end up with tiny molecules of hydrogen and carbon monoxide which can be used to fuel other things.

    So, to summarise:
    1) Thermal gasifiers that accept a variety of polymers and break them down into gases that can be used as fuels exist. They are the size of ISO containers.
    2) A plant which converts tyres to 90-95% diesel? I don't buy it.
    3) Drive at 55mph to save fuel. The power you expend against drag increases to the cube of your speed. I note a ~10% improvement in MPG when I drive on motorways at 55mph instead of 70mph.
     
    • Like Like x 1
  13. This looks like a version of a process called Catalytic Pyrolysis, that's been knocking around for years. The Chinese use it quite widely, I believe.