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Solution needed for sieving of small but long plastic material

Solution needed for sieving of small but long plastic material

Solution needed for sieving of small but long plastic material


I'm in search of a solution for a sieving problem I have.
In our process we sieve our material to be <12mm after grinding.
The material is a plastic bottle (with cap).

The as we all know just under the cap of a plastic bottle is a strip to secure the cap when the bottle is not used yet.
The problem lies with these strips. When they go to our grinding process they will pass a 12mm sieve because they are very small, eventhough they are longer than 12mm.

This is a problem for our customer because they need material to be <12mm but we can't sieve those strip pieces in a good way.
I figure this is a problem which probably isn't experienced only in our process but in other processes also where they try to sieve and have problems with long small materials.

Does anyone know of a solution to this problem?

Thanks in advance!

RE: Solution needed for sieving of small but long plastic material

Water flotation - PET has specific gravity higher than water, PP is lower.

RE: Solution needed for sieving of small but long plastic material

Yes that is used allso but after the grinding. PET and HDPE are grinded together. We need a way to sieve off everything smaller than 12,5mm (those long pieces not included) before it goes in the floatation tanks.

RE: Solution needed for sieving of small but long plastic material

Try Googling matchstick sifters. They have a corrugated screen with slots in the bottom, the match sticks orient one way on the screen, the slots remove the short sticks. A different set of slots remove the long sticks.

You are judged not by what you know, but by what you can do.

RE: Solution needed for sieving of small but long plastic material

Thanks for the input, most helpful!

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