3-5T/H Fish Feed Pellet Cooler in Norway

The plant was producing 5 tons/hour of 10mm sturgeon pellets. They had an old cooler with a fixed cooling time that couldn't be adjusted. Lars started looking for a fish feed pellet cooler that could handle large-diameter pellets with extended cooling time.

From the cooler table, the SKLF14x14 (1.5kW) was selected. Why this model?

• Capacity: 3-5 tons/hour – matches their 5 t/h output
• Cooling time: 6-15 minutes (adjustable) – set to 14 minutes for large pellets
• Final temperature: Ambient +3-5°C – ensures core is cool
• Counterflow design: Most efficient cooling for large, dense pellets
• Extended residence time: Allows heat to migrate from core to surface
• Gentle discharge: Swing tray prevents breakage of large pellets

Lars chose the SKLF14x14 to replace their inadequate cooler. The new cooler would be installed directly after the pellet mill.

What He's Cooling – Large-Diameter Sturgeon Pellets

Norway is a leader in aquaculture. The plant produces:

• Raw materials: Fish meal (40-45%), fish oil (15-18%), wheat flour, soybean protein concentrate
• Pellet diameter: 10mm (for adult sturgeon, 3-10kg fish)
• Pellet length: 15-25mm
• Pellet density: High (sinking type)
• Incoming pellet temperature: 80-85°C (after pellet mill)
• Target temperature: 18-22°C (ambient +3-5°C in Norway)
• Target core temperature: Below 25°C

The pellets are used for:

• Sturgeon farming (caviar production) – premium market
• Export to Russia, France, Italy – high-value product

Installation – Extended Cooling for Large Pellets

The SKLF14x14 fish feed pellet cooler arrived at the Port of Trondheim – a major port in central Norway.

Shipping time from Qingdao to Trondheim is about 30-35 days. The machine was packed in a 20-foot container with:

• SKLF14x14 cooler main unit (1.5kW discharge motor)
• Hydraulic power pack for swing tray mechanism
• Rotary airlock feeder (stainless steel)
• Control panel with PLC
• Spare discharge trays (one set)
• Installation manual and electrical diagram in Norwegian

Customs clearance in Trondheim took about 3 days. Total landed cost was about 20% higher than the FOB price.

Installation took two weeks. The old cooler was removed. The new SKLF14x14 was positioned on a raised platform to allow gravity discharge into the bagging line. A concrete foundation (150mm thick) was poured.

The electrical hookup required 400V, 50Hz three-phase (Norwegian standard). The 1.5kW discharge motor plus hydraulic pack required a 30-amp breaker.

The first test run was with 10mm sturgeon pellets at 82°C. The cooler was set to 14 minutes cooling time (extended for large pellets). Surface temperature exiting: 20°C. Core temperature measured by probe: 22°C (ambient was 17°C). No mold in test bags after 8 weeks.

Performance – Core Cooling Achieved

After six months of operation, Lars documented the following results:

Before (old cooler – fixed 8 minutes):

• Cooling time: 8 minutes (insufficient for 10mm pellets)
• Surface temperature: 30-35°C
• Core temperature: 45-50°C (still warm)
• Mold growth in bags: 15-20% of production within 8 weeks
• Customer complaints: 3-4 per month about "moldy feed"
• Returned product: 10-12% of production
• Annual loss: NOK 2,500,000 (€220,000)

After (SKLF14x14 – adjustable, 14 minutes):

• Cooling time: 14 minutes
• Surface temperature: 18-22°C
• Core temperature: 20-24°C (uniform)
• Mold growth in bags: <1% (normal handling)
• Customer complaints: Zero in six months
• Returned product: <1% (normal production waste)

Production impact:

• Pellet mill runs at full capacity (5 t/h) without cooling bottleneck
• Feed can be stored for 6+ months without mold
• Export shipments to Russia and France are stable

Customer Feedback – Lars's Experience

Here's what Lars said after six months (paraphrased from a conversation, translated from Norwegian):

"Large pellets are different. The core stays warm long after the surface cools. Our old cooler didn't have enough residence time. The pellets looked cool on the outside, but the core was still 45°C. After a few weeks, mold grew from the inside out.

The SKLF14x14 fish feed pellet cooler changed that. We set the cooling time to 14 minutes – long enough for the heat to migrate from the core to the surface. The core temperature is now 20-22°C, uniform with the surface. No more mold.

The adjustable cooling time is essential for large pellets. The counterflow design is efficient. The swing tray discharge is gentle – no breakage of the 10mm pellets.

Would I recommend this cooler? Yes. For any fish feed mill producing large-diameter pellets (8-12mm), extended cooling time is essential. The SKLF14x14 paid for itself in three months."

Why Large Pellets Need Extended Cooling

Large-diameter pellets (8-12mm) have different cooling requirements than small pellets:

Heat migration time: Heat from the core must travel 5-6mm to reach the surface. For 4mm pellets, distance is 2mm – cools in 6-8 minutes. For 10mm pellets, distance is 5mm – needs 12-15 minutes.

Core temperature measurement: Surface temperature can be 20°C while core is still 45°C. The cooler must run long enough for heat to migrate.

Mold risk: Warm cores cause moisture migration during storage. Condensation forms inside the pellet, leading to mold growth from the inside out.

Pellet density: Sinking pellets (for sturgeon, salmon) are denser than floating pellets. Dense pellets retain heat longer.

The Cooling Process – Core Temperature Control

The SKLF14x14 fish feed pellet cooler's extended cooling time allows heat migration:

1. Hot pellets enter at 80-85°C, 10mm diameter
2. Surface cools quickly in the first 6 minutes
3. Heat migrates from core to surface (minutes 6-12)
4. Final cooling removes remaining core heat (minutes 12-14)
5. Cooled pellets exit with uniform core temperature (20-24°C)

Lars's core temperature testing:

• Cooling time 8 minutes: Surface 30°C, Core 45°C (unsafe)
• Cooling time 10 minutes: Surface 25°C, Core 38°C (still unsafe)
• Cooling time 12 minutes: Surface 22°C, Core 30°C (marginal)
• Cooling time 14 minutes: Surface 20°C, Core 22°C (safe)

Core Temperature Measurement Technique

Measuring core temperature of large pellets requires a probe:

1. Select a pellet immediately after discharge
2. Insert a thin thermocouple probe into the center
3. Wait 30 seconds for reading to stabilize
4. Target: Core temperature below 25°C

Lars checks core temperature every hour.

Pellet Size vs. Cooling Time

The SKLF14x14 fish feed pellet cooler's adjustable timer (6-15 minutes) covers all sizes.

Gentle Discharge – Preventing Large Pellet Breakage

Large pellets (10mm) are more fragile than small pellets. The SKLF's swing tray discharge:

• Gentle opening – no impact
• Smooth discharge – pellets fall, not crush
• No screw conveyor – eliminates auger breakage

Lars's breakage testing:

• Old cooler (screw discharge): 5-7% fines
• SKLF14x14 (swing tray): 1-2% fines (70% reduction)

Sturgeon Feed – Premium Market Requirements

Sturgeon feed is a high-value product (€2,000-3,000/ton). Customers demand:

• No mold – caviar producers cannot risk fish health
• Consistent size – 10mm pellets for adult sturgeon
• Sinking behavior – pellets must sink quickly (dense)
• Long shelf life – 6+ months in storage

The SKLF14x14 helps meet all these requirements.

Shipping – Qingdao to Trondheim

The SKLF14x14 shipped from Qingdao to Port of Trondheim, Norway.

Shipping time from Qingdao to Trondheim is about 30-35 days. The route goes through the South China Sea, past Singapore, across the Indian Ocean, through the Suez Canal, across the Mediterranean, and up the Atlantic to Norway.

The machine was packed in a 20-foot container. Customs clearance in Trondheim took about 3 days. Total landed cost was about 20% higher than the FOB price.

The truck transport from Trondheim to Trøndelag was short – about 50km, roughly 1 hour.

What Lars Learned – Lessons for Other Fish Feed Mills

After six months of running the SKLF14x14, Lars shared several observations:

Lesson 1: Large pellets (8-12mm) need extended cooling time (12-15 minutes). Standard cooling times for small pellets are insufficient.

Lesson 2: Measure core temperature, not surface temperature. Surface can be cool while core is still hot. Use a probe.

Lesson 3: Adjust cooling time based on pellet diameter. Lars has a chart on the wall: 4mm=8min, 6mm=10min, 8mm=12min, 10mm=14min.

Lesson 4: Sinking pellets take longer to cool than floating pellets. Higher density retains heat longer.

Lesson 5: Monitor stored bags for mold. Lars keeps sample bags in a warm room (25°C) for 8 weeks. If mold grows, increase cooling time.

What RICHI Provided Beyond the Machine

RICHI provided several services that helped Lars get the SKLF14x14 operational:

• Norwegian documentation: The manual and electrical diagram were provided in Norwegian.
• Extended cooling guidance: RICHI provided cooling time recommendations for large pellets.
• Core temperature advice: RICHI provided techniques for measuring core temperature.
• Stainless steel recommendation: RICHI recommended stainless steel for fish oil resistance.
• Spare parts kit: RICHI recommended a spare parts kit – discharge trays, hydraulic seals, bearings.
• Remote support: When Lars had questions about cooling time adjustment, a RICHI technician walked him through the PLC settings.

Is a Fish Feed Pellet Cooler Right for Your Operation?

For a fish feed mill producing large-diameter pellets (8-12mm), a counterflow cooler with adjustable cooling time is essential.

Consider the SKLF14x14 if:

• Your capacity requirement is 3-5 tons/hour
• You produce 8-12mm pellets for sturgeon, salmon, or other large fish
• You need extended cooling time (12-15 minutes)
• Core temperature control is a priority

Consider a larger model (SKLF17x17) if:

• Your capacity requirement is 6-8 tons/hour

For Lars's fish feed mill, the SKLF14x14 Counterflow Pellet Cooler was the right investment. It eliminated mold (core cooling achieved), reduced returned product by 90%, and paid for itself in three months.

Final Thoughts

If you're a fish feed mill producing large-diameter pellets (8-12mm), don't assume standard cooling times are sufficient. Large pellets retain heat in their core. The surface may be cool, but the core can still be warm enough to cause mold.

The SKLF14x14 fish feed pellet cooler has an adjustable cooling time (6-15 minutes). For 10mm pellets, set it to 14 minutes. The counterflow design ensures efficient cooling. The swing tray discharge prevents breakage. The result is mold-free feed with uniform core temperature.

For large-diameter fish feed, the math is simple: extended cooling = core cooling = no mold = satisfied customers = repeat business.

RICHI offers documentation in Norwegian, extended cooling guidance, core temperature advice, and remote support. Contact RICHI Machinery through the website with your pellet diameter, production rate, and cooling requirements for a recommendation. Tell them about your large-pellet application – they can help you select the right cooler and cooling time for optimal core temperature control.