In general, the process consist in the following: the wood material (sawdust and wood chips) is delivered to the hammer mill where is grinded to 1-3 mm fraction and sent to the cyclone-settler. Dust goes out from the cyclones to the air filtration equipment.
From the cyclone-settler, grinded sawdust goes to the bunker, and through batcher and mixer – to the pellet press. Then the material is pressed through the rotating ring die holes and are formed the pellets. On the outer side of the ring die, a knife cut off the pellets at the desired length.
After extrusion pellets reach 90-100°C temperature and are transported into the cooler, where their temperature decrease to 25°C. This sets up the lignin and hardens the product, and contributes to maintain its quality during storage and handling. Finally it is screened, so as to separate the residual fines which are generally re-used in the process. Dust free pellets are then ready for storage, fed into the packaging equipment and packed according to necessity.
