The dedusting system is composed by the following components:
- Secondary Cyclone
The Pellets enter the deduster by means of gravitational force.
The deduster is connected to the external pneumatic circuit by an inlet flange (at the bottom) and an outlet flange (at the top).
The blower determines inside the deduster a rising helical air flow that runs against the descending flow of the pellets (“counter-flow”) and at the same time increases the air flow velocity by reducing the available cross-sectional area.
The weight of the pellets results greater than the air flow thrust, while the dust particles, with a smaller mass and a more irregular surface, are transported peripherally by the air flow to the top of the deduster, in a zone separated from the pellets inlet cone.
Here the dust particles stay in suspension and are sucked by the aspirator towards a secondary cyclone for the separation.
The polymer pellets are collected down through the duct of the cyclone.
Besides, in order to recover the dust at low speed downwards, thus avoiding dust spreading around, a throttle device at the discharge of upflow air is foreseen.