Manufacturing Process of Pine Wood Pellets
In the manufacturing processes of pine wood pellets, each step must be carried out with care, which involve pine wood debarking, chipping, drying, crushing, pelletizing, cooling & sieving, and packaging.
Pine Wood Debarking
For the pine wood logs, it is not easy to crush directly. The bark need to be removed first. Our wood debarker is a new generation of efficient pine wood logs peeling machine. Take advantage of the special forces, produced by rotor with step-shaped debarking teeth, the wood logs cycle repeatedly on the groove plate of the silo. Besides, the wood logs rotate around themselves and throb irregularly. After peeling, open the door on the side of silo, the debarked wood are discharged automatically. We have single-roller wood debarker and double-roller wood debarker for your selection.
Parameters of Wood Debarking Machine
|Specification||Single roller||Double rollers|
Pine Wood Chipping
Before crushing into the proper size for pelletizing, the wood logs need to be chipped into small pieces first. Drum wood chipper is an ideal equipment to produce large capacity and good quality pine wood chips. This machine is made up of machine base, knife roller, feeding roller, belt conveyor, hydraulic pressure system components. The qualified chips fall through the sieve hole, and the big pieces can not come through the sieve, so they will be chipped again until qualified.
Drum Wood Chipper Technical Data
|Model||BX215||Feeding inlet size||160*400mm|
The best moisture content for pelletizing is 12-15%, our rotary dryer is designed to reduce the moisture of raw materials. The rotary dryer is made up of heat stove, main body, air fan, cyclone, and air lock. It adopts hot air, generated through heat stove, to remove the moisture of wood chips. With the help of air fan’s suction, the hot air flow into the dryer. When wood chips come through the rotary dryer, hot air will pull over chips and under the effect of heat change, the chips will be dried with high efficiency.
Technical Data of Rotary Dryer
|Drum diameter||1.5m||Drum length||12m|
|Transmission power||7.5kw||Air fan power||18.5kw|
|Cyclone model||SKL1200||Air lock power||1.1kw|
The water drop hammer mill is mainly applied to grinding the wood chips to make it suitable to make pellets. The wood chips are transferred into the hammer mill by feeding conveyor and then enter into the grinding chamber. The wood chips are beat by high speed rotating hammers, then hit the sieve plate and bounce back. Wood chips are grinded by the impact force from hammers and friction force from sieve plate. Direct transmission and advanced snake flexible coupling are adopted. Scientific hammer arrangement and hammer sieve intervals make sure the final products are in uniform fineness.
Water Drop Hammer Mill Specification
|Main shaft rotate speed||Hammer line speed||Grinding chamber width|
|Hammer quantity||Power||Normal air volume|
Pelletizing is the core procedure in pine wood pellet production line. In this 2t/h pine wood pellet plant, two 420 ring die pellet machines are equipped. The finely pulverized materials are delivered into the pellet machine through conveyor, then transferred into a ring die by a feeder, finally pressed into ring die through two press rollers. The resulting pressure compresses the materials and extrudes through the holes of ring die. Wood pellets are in the diameter of 6mm, 8mm, 10mm or according to your special requirements.
Ring die pellet machine adopts professional forced feeder and strengthened transmission parts, and the ring die, press roller and hoop are specially customized. Imported high-quality bearings and oil seal are adopted to ensure efficient, stable and low-noise operation. The granulating room is equipped with air suction temperature-reducing system. Compared with belt drive, the capacity of the high-precision gear driving is improved by about 20%.
Parameters of 420 Ring Die Pellet Machine
|Main motor power||90kw||Screw feeder power||2.2kw|
|Ring die inner diameter||420mm||Ring die rotate speed||150rpm|
|Roller outer diameter||165mm||Pellet size||6mm, 8mm, 10mm etc.|
|Roller quantity||2||Roller working temperature||≤85℃|
Cooling & Sieving
The wood pellets come from pellet machine are hot and moist, then a pellet cooler is equipped to reduce the moisture and temperature of wood pellets, thus to improve the hardness and strength. Also it can enhance the ability of transportation and storage. The screening procedure after cooling is mainly used for removing the superfine powders and coarse particles mixed with the final pellets, which can be returned to the pellet mill.
Parameters of Pellet Cooler
|Cooling volume||1.5m3||Cooling time||≥6-10min|
|Power||0.75kw||Air lock power||1.1kw|
After cooling, pine wood pellets are packed into bags or stored in bulk in order to avoid affecting with damp. Please note that the pellets must be kept dry to prevent deterioration. The wood pellets are packed 5-50kg/bag or according to your specific request.
Parameters of Pellet Packing Machine