Equipments used for EPS recycling
It is reported that more than 93 million pounds of EPS was recycled during calendar year 2012 and the number is supposed to increase steadily. The EPS recycling procedure will not work at least not so effective without the help of EPS recycling equipments including EPS shredder, EPS compactor, EPS pelletizing machine etc.
Usually EPS is made into different products, their size can range from small EPS containers to bulky construction materials. Shredders can help break them into small particles with homogeneous distribution which makes it easier for compacting or pelletizing.
It seems to be a waste of energy to compact/densify EPS after the shredding process. However, it should be noticed that EPS is made of more than 90% air. The transportation of EPS without compaction is costly and ineffective. The shredding process broke the cell structure of EPS and thus make it possible to compact. There is another kind of compacting method which use external thermal energy to melt the EPS and let go of the gas inside which is usually named thermal compactor or densifier. Actually, the compacted EPS must be shredded again before pelletizing.
EPS pelletizing machine
In the pelletizer, shredded EPS is mixed with blowing agent and other additives, after melt, extrude, cooling and eventually cut into PS beads. The PS beads can be used for injection molding and extrusion to make products such as coat hangers and picture frames.