machine that makes styrofoam pellets

Discussion in 'Shop Talk' started by John_in_Houston, Feb 3, 2005.

  1. John_in_Houston

    John_in_Houston Well-Known Member

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    Been thinking about concrete structures, which led to thinking about lightweight concrete, which led to thinking about how polystyrene pellets are made.

    Anyone out there have any idea what is involved in making them or how much a setup might run?
     
  2. ex mek

    ex mek Member

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    I read something somewhere about Indian road repairs , they somehow introduce compressed air to make bubbles to lighten the concrete.
     

  3. Cosmic

    Cosmic Well-Known Member

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    Basically it is a molding process. Styrene is injecting in some form and heated, steam is one common method.

    Those common shipping peanuts are like 99% air so very little material involved. Comes under the general category of expanded polystyrene foam.

    I have no idea of the costs or who might make such equipment.
     
  4. gobug

    gobug Well-Known Member Supporter

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    you can take discarded foam and run it through the chipper/shredder

    another approach that works is a weed wacker in a bucket, but it's harder to keep the stuff in the bucket

    static electricity will build up, so you'll need a ground wire

    mix a quarter teaspoon of dawn liquid soap in with the cement mix so the beads don't float to the top, add some flyash also.
     
  5. Bob_W_in_NM

    Bob_W_in_NM Well-Known Member

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    You might search "air entrained concrete" and see what you come up with.
     
  6. Cosmic

    Cosmic Well-Known Member

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    Light weight concrete and polystyrene pellets don't have much in common. Most light weight concretes are complex and replace the aggregates with something lighter. Usually something like gypsum, perlite or whatever. Basically a very complex subject, not many new practical mousetraps being invented every day, week, month or even year.

    A science of additives, materials,methods, placement and techniques. Get any one of them wrong and it can bite you. The Romans probably understood it as well as anyone.

    BTW... This idea of air entrainment in concrete has little to do with making it lighter. As I said very complex, better to research why fly ash works as an additive. Air addition has a place, it is not any sort of a magic bullet. Many things work, but as techniques that are both well understood and implemented, at both an engineering and workman level.
     
  7. Lt. Wombat

    Lt. Wombat Well-Known Member

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    We bought a case of packing pellets from U-haul that are pure corn starch. When you're done with them (and don't want them anymore) you just wet them and they melt down to their original form (whitened water). Much more enviro friendly!