1. Overview
After pelleting, feed or wood pellets are typically 80-90℃ hot and 17-18% moisture-rich—too 湿热 to package, transport, or store directly (prone to mold, cracking, or even spontaneous combustion for wood pellets). The Counterflow Pellet Cooler is a specialized post-processing device engineered to solve this problem, leveraging the countercurrent cooling principle to efficiently reduce pellet temperature to 3-5℃ above ambient and moisture content to 12-13%.
With core advantages of energy efficiency, superior cooling results, easy operation, and low investment, it has become the preferred choice for medium-to-large feed pellet plants and wood pellet production lines—ensuring pellet integrity, extending storage life, and laying the foundation for subsequent processes (grading, coating, packaging).
2. Core Value: Why Cooling Is Indispensable
Skipping the cooling step leads to irreversible product losses. The counterflow pellet cooler delivers three critical values for production:
2.1 Protect Pellet Quality & Integrity
Hot, moist pellets are soft and fragile. Direct cooling with cold air (shock cooling) causes surface contraction faster than the interior, leading to cracks or breakage. The counterflow principle lets cold air gradually contact pellets from the bottom up, avoiding thermal shock—keeping pellets smooth, dense, and free of defects.
2.2 Extend Storage & Transportation Safety
- Moisture Control: Reducing moisture to 12-13% prevents mold growth during storage (mold thrives above 14% moisture), extending shelf life from 1-2 months to 6-12 months.
- Safety Assurance: For wood pellets, cooling eliminates residual heat to avoid spontaneous combustion risks during bulk storage; for feed pellets, low moisture prevents nutrient degradation.
2.3 Adapt to Subsequent Production Processes
Cooled, low-moisture pellets are stable enough for grading, coating, or automatic packaging—avoiding equipment blockages (e.g., in packing machines) and ensuring smooth downstream operations.
3. Core Features & Benefits
3.1 Counterflow Principle: Gentle & Effective Cooling
The cooler adopts a “pellet down, air up” countercurrent design: hot pellets enter from the top and fall slowly, while cold air is drawn from the bottom and flows upward. This gradual heat exchange avoids thermal shock, reduces pellet cracking rate by over 90%, and ensures uniform cooling (no local overheating).
3.2 Structural Design for Zero Dead Zones
- Octagonal Cooling Tank: Unlike traditional cylindrical tanks, the octagonal design eliminates cooling blind spots—every pellet contacts cold air fully, ensuring consistent temperature/moisture across batches.
- Air-Closed Material Feeder: Features a large air intake area and sealed structure, maximizing air utilization efficiency while preventing cold air leakage—cooling speed is 30% faster than ordinary coolers.
3.3 Stable Operation & Low Maintenance
- Slide Valve Reciprocating Discharger: Ensures steady pellet discharge with minimal residue (≤1% residual rate), avoiding material buildup and reducing cleaning workload.
- Energy-Saving Performance: Total power ranges from 1.12Kw (small model) to 2.05Kw (large model), consuming 40% less electricity than cross-flow coolers; easy to operate and clean (detachable cooling plates for dust removal).
3.4 Versatile & Reliable Performance
Suitable for both dense feed pellets and porous wood pellets, with a cooling time of 6-10 minutes—balances efficiency and quality, supporting 3-20t/h production lines.
4. Application Scenarios
4.1 Feed Industry
- Cools hot feed pellets (chicken, pig, aquatic feed) after pelleting, reducing moisture and temperature to meet packaging standards—ensuring feed stays fresh during long-distance transportation.
- Critical for high-protein or high-fat feed (e.g., aquatic feed), as low moisture prevents nutrient oxidation and mold growth.
4.2 Wood Pellet Industry
- Lowers the temperature of wood pellets (made from sawdust, straw) to avoid spontaneous combustion in silos; reduces moisture to prevent decay, ensuring pellet calorific value stability.
4.3 Other Granular Materials
Also applicable to cooling compound fertilizer pellets and biomass fuel pellets—any granular product requiring post-pelleting temperature/moisture control.
5. Operation & Maintenance Guidelines
5.1 Safe Operation Procedures
- Pre-Start: Turn on the airlock device and draught fan first (wait 1-2 minutes for stable airflow) before feeding pellets.
- Yield Adjustment: Set the level indicator position based on capacity—high yield (e.g., 20t/h) → top position; low yield (e.g., 3t/h) → lower position.
- Shutdown: Stop feeding first, then use the hand switch to empty pellets in the cooler before turning off the fan and airlock.
- Safety Rule: Do not open the observation door during operation (risk of hot pellet splashing or airflow disturbance).
5.2 Routine Maintenance
- Daily: Clean cooling zone plates to keep airflow unobstructed (prevent dust buildup from reducing cooling efficiency).
- Weekly: Check fasteners (bolts, nuts) for looseness; add lubricating oil to bearings and motor (use 3# lithium grease).
- Monthly: Inspect the slide valve discharger for wear; replace seals if air leakage is detected.
6. Selection Guide
Choose the right model based on production capacity and pellet type:
6.1 Model vs. Capacity Matching
| Production Capacity | Recommended Model |
|---|---|
| 3t/h | SKLN1.5 |
| 5t/h | SKLN2.5 |
| 10t/h | SKLN4 |
| 15t/h | SKLN6 |
| 20t/h | SKLN8 |
6.2 Discharger Type Selection
- Slide Valve Reciprocating Type (standard for all models): Suitable for ordinary feed pellets and wood pellets (dense, non-puffy particles).
- Shutter Type (Hydraulic Discharge) (customizable): For puffed/expanded materials (e.g., floating aquatic feed, puffed grain pellets)—avoids particle deformation during discharge.
7. Technical Parameters
| Model No. | Cooling Volume | Productivity | Applicable Power | Airlock Power | Total Power |
|---|---|---|---|---|---|
| SKLN1.5 | 1.5m³ | 3t/h | 0.75Kw | 0.37Kw | 1.12Kw |
| SKLN2.5 | 2.5m³ | 5t/h | 1.1Kw | 0.55Kw | 1.65Kw |
| SKLN4 | 4m³ | 10t/h | 1.5Kw | 0.55Kw | 2.05Kw |
| SKLN6 | 6m³ | 15t/h | 1.5Kw | 0.55Kw | 2.05Kw |
| SKLN8 | 8m³ | 20t/h | 1.5Kw | 0.55Kw | 2.05Kw |
Unified Performance Indicators:
- Cooling Time: ≥6-10 minutes
- Pellet Temperature After Cooling: ≤ Ambient temperature +3-5℃
- Aspirating Capacity: 34m³/min
- Moisture Reduction: From 17-18% to 12-13%