powder and pellets extrusion

[gwenls]

Hello,

I am involved in the design of a finishing section of a polyolefin plant.
Is there any issue in extruding pellets and powder at the same time? Does it cost much more than doing the two separatly?
This would be to extrude off grade pellets with powder from reactor.

Thanks,
Gwen

 

[JeffdlS]

Gwen,

It really depends on the materials of the pellets & powder. If they are compatible with each other, then there shouldn't be too much of a problem extruding both together. What materials are the components?

Jeff

 

[gwenls]

Thanks Jeff,

The product is the same and is pelletized to comply with the production wheel. It is after reprocessed with powder coming directly from reactor (both are polypropylene of same MFI).
Does that imply a high cost increase of the extruder (10t/h)? What about the typical market price for 10 or 25t/h extruders for PP?...

Gwen

 

[plasticsguru]

Gwen,

It is possible but the main issue will be sifting of the powder through the gaps in the pellets assuming you are pre blending. If you feed the powder and pellets seperately using different feeders you should not have any problems. As a side note I may be interested in purchasing your off spec PP can you give your contact information so we can discuss? My email is sjkman@yahoo.com.

Thanks