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The steps taken to recycle post-consumer plastics may vary from operation to
operation, but typically involvewashing and conversion into either flakes or
pellets. Pellets are made by melting down the plastic and thenextruding it
into thin strands that are chopped into small, uniform pieces. Pellets and
flakes are the form in which plastic feedstocks are sold - whether they’re
virgin or recycled. Thespecific reclamation steps taken by a recycler may
depend upon the recycler’s confidence in the handler’spreparation of the
plastics coming into the facility.
Steps in Recycling Generic Plastics
- Inspection: Incoming plastics are inspected for contaminants, as
well as for types of plastic the recycler can’t accommodate.(Some plants
handle several types of post-consumer plastics, while others may handle only
one).
- Granulating/Washing: Plastics are “chopped” in a grinder and
washed. (The waste water is not hazardous and may be filtered andreused).
- Flotation Tank: If mixed plastics are being reprocessed, they are
separated in a flotation tank. (Some plastics sink, other’s float).
- Drying: Clean plastic flakes must be thoroughly dried. (Dampness
may result in a low-quality end product).
- Melting: The dry flake is fed into an extruder where heat and
pressure melt the plastic. (Each type of plastic has a differentmelting
point).
- Filtering: The molten plastic is forced through a fine screen to
remove any contaminants that may have eluded the washingcycle.
- Pelletizing: The strands are cooled, chopped into pellets, and
stored for sale and shipment.
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