Counter Flow Wood Pellet Cooler

A Wood Pellet Cooler is an essential piece of equipment in a biomass pellet production line. It is used to reduce the temperature and moisture content of freshly made wood pellets, improving their hardness, storage stability, and overall quality. The Fresh pellets come out of the pellet mill at high temperatures (around 70–90°C) and with relatively high moisture content. Without proper cooling, they can deform, break apart, or develop mold during storage. The wood pellet cooler solves these issues efficiently and consistently. It adopts counter-flow cooling technology, generating a premium effect of maintaining the integrity of the biomass pellets. It reduces the pellets’ temperature to near ambient levels and reduces the pellet moisture content from 18% to 12%. It features large capacity (ranging from 1 t/h to 10 t/h), smooth functioning, and high efficiency.

• Prevents pellet deformation, breakage, and clumping
• Increases pellet density and durability
• Ensures long shelf life and better packaging performance
• Essential for commercial pellet production and export compliance
• Improves downstream processes like bagging and storage

• Dust removal system (cyclone or bag filter)
• A vibrating or rotary screen beneath the cooler to remove fines
• Automatic Pellet Weighting and Bagging machines
• Conveyors for continuous production
• Integrated temperature and humidity sensors

• Efficient Cooling Capacity: Rapidly lowers pellet temperature from 70–90°C to near ambient levels.
• Moisture Reduction: Helps reduce moisture to a stable level (~10–12%), preventing mildew or degradation.
• Durable Construction: Made from high-quality steel to ensure long-term performance.
• Uniform Cooling: With a rotary distributor, the pellets can be cooled evenly in the bin room. Using the pendulum discharger, gentle discharge can be achieved. Guarantees even airflow and consistent results across all pellets.
• Low Power Consumption: Energy-efficient operation with high output. Large capacity, low noise, and high automation degree.
• Easy Operation & Maintenance: User-friendly control system and simple mechanical structure.
• Automatic pellet flow control system. Automatically adjust the height of pellets in the bin.
• Counter-flow Pellet Cooling Principle: The cooling air reverses the pellets, and the pellet is cooled from the bottom to top gradually; thus, the cooling time is increased and the biomass pellets are cooled evenly and thoroughly.

1. Pellet Feeding. Hot pellets made from the biomass pellet mill enter the cooler through the top feeding inlet.
2. Pellets Distribution. Underneath the inlet rotary valve, a distributor ensures even distribution of pellets in the cooler.
3. Airflow Introduction. A fan introduces ambient air from the bottom and sides.
4. Counterflow Cooling Process. Cool air flows upward as pellets move downward. This counterflow design ensures gradual and even cooling, avoiding thermal shock and cracks.
5. Automatic Pellet Flow Control System. In order to prevent overflow, the cooler is equipped with an overflow sensor. The pellet layer height is controlled by a level sensor. The level sensor ensures that the pellet layer is kept at a predetermined height. As soon as pellets activate the level sensor, the pendulum discharger is operated and pellets are discharged through the hopper. Discharging stops as soon as the product gets below the level sensor.
6. Discharge System. Once cooled, pellets are discharged via a rotating discharge valve or slide gate, ready for screening or packaging.

The counter flow cooler consists of these parts: inlet rotary valve, cooling bin, distributor, discharge gate, air outlet, level sensor, hopper, pendulum discharger & overflow sensor.

• Inlet Rotary Valve. Equivalent to the feeding device. The hot pellet comes into the cooling bin through the inlet rotary valve.
• Pellet Distributor. Ensure the flatness and uniformity of the pellets in the bin room.
• Pellet Level Sensor. Adjust the height of pellets in the bin. When the height of the pellets is above a certain height, the discharger will work and release the processed pellets. Discharging stops as soon as the product gets below the level sensor.

Tip for Pellet Coller Operation and Maintenance
1. The cooler should be based on a strong level ground with the anchor bolts. Before functioning, discharging institutions should be adjusted to a horizontal position with a level instrument, and the support feet should be fully filled.
2. Before feeding, empty the machine first, and check whether the internal parts of the machine are functioning normally.
3. Add grease lubrication to the feeder bearing and gear reducer at a regular time.
4. During long-term storage, the pellet cooler should be placed in a ventilated, dry, shady, and cool place.