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Plastic scrap or waste comes in all manner of shapes and sizes such as
plastic bottles, bottle crates, plastic pallets and car bumpers and a variety
of material types. Often these plastic materials are not compatible with each
other when it comes to recycling so they have to be identified and separated.
It is also necessary to strip off any extraneous materials such as metal or
foam which will hinder the recycling process at a later stage.
It may also be necessary to clean the scrap (particularly if the plastic
waste comes from packaging applications such as plastic milk bottles).
Before the plastic waste can be melted down and recycled into plastic
pellets for moulding into new products it must be reduced in size. At its most
basic this is a case of sawing large items of scrap so that they will fit down
the throat of the granulation machines.
Shredding is a much more efficient way of reducing the size of large scrap
plastic items. A shredder basically consists of a large tank that the scrap is
fed into, at the bottom of which are heavy duty rotating blades which quite
literally rip the plastic to shreds.
The output of the shredding process is irregular sized strips of plastic
which will be up to several inches in length (still too big for the
compounding process).
| Sorting |
Identifying components
of differing polymer types to allow them to be processed separately and
thus ensure the highest quality feedstocks |
| Sawing |
we can often be dealing with moulded or extruded components
which are just too large to fit into our machines and so they have
to be cut down to size. |
| Stripping |
The scrap are often
post-consumer or post-industrial components which have been assembled
into products. This means that they can include metal components, different
polymer types and plastic or paper labels. To maintain the quality of the resulting
feedstocks, all of these extraneous items must be removed. |
| Shredding |
Shredding is a quick and efficient way
of reducing large unwieldly plastic components into a manageable format.
The process involves a spinning rotor which rips the plastic apart. The
resulting output is irregular shaped, roughly cut product which is generally
still too large to use into our compounding processes. |
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Molding
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