Elant company suggest to have the two stage extrusion pelletizing system with a cutter compactor for processing LDPE, LLDPE, and HDPE film (post-industrial, post-commercial, and post-consumer). And you can add a separate shredder for the PP material which is much more difficult to shred and slowed the rate down.
It also need to have a melt filter/hydraulic screen filter on the line to remove labels, etc. and it works well with the Elant pelletizer. If you will likely be processing your own film so you would not need the melt filter unless you were to use recycled content from post-consumer or post commercial film back into your film.
The machine capacity will be based upon material bulk density. Bulk density often depends upon screen size with a regular shredder and with a shred drum the toughness of the material partly determines how finely it is shredded along with the condition of the blades and how tightly the shredded material is packed into the screw. LLDPE film runs at a slightly slower rate than the LDPE film for this reason. BOPP film will run at little lower capacity than LDPE films.
Part of the rate determination is the learning curve with the cutter compactor. Sometimes we have found that we can run the shred drum at elevated temperatures to increase the rate and use the water injection system to keep the plastic in the shred drum from melting completely. After the operators have experience doing this, they become very adept at maintaining rate. The double vacuum system removes the water from the melt very effectively and we would definitely recommend the double degassing unit if you will run printed film. The double de-gassing (vacuum) system really makes a very good quality of the pellet.
With a compactor the rate at which you feed it is everything. If you overfeed the compactor you will have problems and if the feeding rate varies much you will have problems. The line operators first learn to feed the line at a steady rate and then they learn their other tasks. Again, this is a learning experience to achieve rate and the average rate is probably 20% lower than the instantaneous rate due to operational issues such as screen changes and other operational issues.
You should install the best water cooling system as you can, you can use a cooling tower, also you may need a chiller, and a very good filtration system for the water to remove pellets and fines. With the right design, the extruder will operate without problems but without proper cooling and filtration, the extrusion system will become contaminated and this will affect the operation of the extruder.
Elant company are available to talk to any potential customers and welcome a visit to our factory to see a line in operation or would like to perform a trial. We are happy to show it off.