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Counterflow Dryer
for Extruded Feed

The drying solution for fish feed and pet food. The counterflow principle achieves ±0.5% drying accuracy and reduces specific heat consumption to just 2,500 kJ/kg of evaporated water.

8%
Outlet moisture
±0,5%
Drying Accuracy
1–12 t/h
Capacity
400–600 kW
Thermal power
Technical Parameters Request a Quote
Counterflow Dryer for Extruded Feed SE 14xx14
Grinding
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Mixing
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Extrusion
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Drying
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Cooling
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Coating
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Packaging

The SE 14xx14 Dryer integrates directly between the extruder and cooler within the continuous food production line

About the Machine

What is a Counterflow Dryer?

The SE 14xx14 extruded feed Counterflow Dryer is a key component in industrial fish feed and pet food production lines. Using the counterflow air principle, the system achieves maximum energy efficiency and uniform drying.

The dryer reduces the moisture content of wet pellets exiting the extruder — from 20–22% down to the target 8% — with full automatic process control. Pellets leaving the extruder have high moisture content and a temperature above 100°C. Without adequate drying, such a product cannot be safely stored, as microorganisms and mould would quickly degrade the feed.

The dryer thermally stabilises the pellets, ensuring a shelf life of 3–6 months without freezing — by reducing moisture below 10%, the water activity value (a_w) drops below 0.6, the threshold below which pathogenic organisms cannot grow.

Interactive Diagram

Counterflow Dryer Diagram

Click on a dot to learn more about that component

Counterflow dryer diagram SE 14xx14
Wet pellets inlet
Drying chamber
Heated air inlet
PLC Control
Dried pellets outlet

Gold dots = key process elements  ·  Teal dots = control systems

Technology

Counterflow Drying Principle

1

Condition at the extruder outlet

Pellets enter the dryer with 20–30% moisture and a temperature of 80–110°C. The porous structure created during extrusion facilitates moisture diffusion during drying.

2

Counterflow of material and air

Wet pellets enter from above, dry heated air enters from below — they travel toward each other. Dry air meets the driest pellets; saturated air meets the wettest.

3

Intensive Drying Phase

Pellets are hot and wet — moisture evaporates rapidly from the surface. The high pellet temperature drives rapid initial drying.

4

Constant Drying Phase

Moisture diffuses from the pellet interior to the surface at a constant rate. The air absorbs moisture at a steady pace.

5

Falling-Rate Drying Phase

Diffusion slows down; precise control of temperature and airflow is critical for reaching the target moisture of 8% ±0.5%.

6

Gravity Outlet — Gentle Handling

Dried pellets exit by gravity without mechanical belts, minimising breakage and preserving the porous structure important for subsequent oil coating.

Key Process Parameters

Inlet pellet moisture 20–22%
Outlet moisture 8% ±0.5%
Drying duration 15–30 min
Pellet inlet temperature 80–110°C
Specific heat consumption 2.500 kJ/kg
Temperature accuracy ±0.5% moisture
Aktivitet vode (aᵥ) na izlazu < 0,6

The counterflow principle allows exhaust air to exit close to the dew point — air is used to the maximum without unnecessary heat loss.

Energy Flexibility

Heating Medium Types

Steam (Water Vapour)

Steam/air heat exchanger

The most practical solution for industrial plants with a central boiler house. Steam passes through a tube or plate heat exchanger, heating the air introduced into the dryer. Precise temperature control with no direct contact between fuel and feed. Waste steam from the extruder can be reused to increase overall facility efficiency.

Industry standard

Natural Gas

Direct combustion in a burner

Direct combustion of gas in a burner heats the air entering the dryer. Simple installation, fast temperature regulation and low equipment cost. Suitable for plants with existing gas infrastructure and facilities where gas is a cost-effective energy source.

Quick installation

Heat Pump

Lowest specific energy consumption

COP coefficient of 3–5 — for every kW of electrical energy, 3–5 kW of heat is delivered. Ideal for facilities with strict CO₂ reduction requirements. Heating air temperature typically up to 60–70°C, sufficient for gentle drying of smaller capacities.

COP 3–5 · Eco-Friendly

Biomass Boiler

Wood pellets or agro-pellets

Burning wood pellets or agro-pellets (straw, sunflower, grain mass) in a boiler generates warm air that is fed into the dryer. A CO₂-neutral energy solution. Fuel costs are lower than gas and electricity — particularly suitable for facilities with their own raw material.

CO₂ neutral
Key Advantages

Why Choose SE 14xx14?

Energy Efficiency

Counterflow design uses drying air up to the saturation limit. Specific heat consumption of only 2,500 kJ/kg of evaporated water — significantly below belt dryers.

Drying Uniformity ±0.5%

Guaranteed moisture tolerance of ±0.5% minimises over-drying. On a line of 75,000 t/year, this prevents the loss of 2,250 tonnes of finished product worth >€1M.

Gentle Pellet Handling

Gravity flow without mechanical belts reduces breakage and preserves the porous pellet structure, which is critical for subsequent coating with oils and vitamins.

Compact Design

Smaller footprint compared with multi-deck belt dryers of the same capacity. Vertical gravity flow eliminates the need for long horizontal runs.

Heating Medium Flexibility

Compatibility with steam, gas, heat pumps and biomass allows adaptation to available energy infrastructure without modifying the dryer.

Continuous Operation

The dryer operates continuously in-line, without batch operation. It increases line throughput and eliminates downtime between drying cycles.

HACCP & Sanitacija

Closed system without a belt reduces feed residue build-up. No belt contamination, facilitating sanitation in compliance with HACCP and GMP standards.

PLC Automatic Control

Continuous real-time moisture measurement at the outlet. The PLC automatically adjusts temperature, airflow and material movement speed without manual supervision.

Shelf Life 3–6 Months

By reducing moisture below 10%, a_w drops below 0.6 — pathogenic organisms and mould cannot grow. Safe storage without freezing.

Specifications

Technical Parameters

Parametar SE 14x14/400 SE 14x14/600
Thermal power 400 kW 600 kW
Installed electrical power 11,4 kW 11,4 kW
Inlet pellet moisture 20–22% 20–22%
Outlet pellet moisture 8% 8%
Outlet moisture measurement Continuous Continuous
Drying Accuracy ±0,5% ±0,5%
Drying duration 15–30 min 15–30 min
Line capacity do 8 t/h do 12 t/h
Moisture reduction
20–22% → 8%
With continuous outlet measurement
Specific heat consumption
2.500 kJ/kg
Of evaporated water — at optimal operating conditions
Drying Accuracy
±0.5% moisture
Guaranteed tolerance
Instalisana el. snaga
11,4 kW
Both models — low electrical consumption
Impact on the Final Product

Moisture Control and Feed Quality

🐟

Water Stability (Fish Feed)

Pellets must remain intact for a certain time in water so fish have time to eat them. Excessive moisture makes pellets soft and unstable, while too little can cause crumbling. Counterflow drying achieves the precise target moisture for optimal floating characteristics.

🧪

Fat Absorption and Coating

Counterflow drying preserves the porous pellet structure formed during extrusion. This porosity is critical for the subsequent oil-coating step — fats, vitamins and flavours penetrate deeper into the pellet, improving the nutritional value and palatability of the finished feed.

🦠

Microbiological Safety

By reducing moisture content below 10%, the water activity value (a_w) drops below 0.6 — the threshold below which pathogenic organisms and mould cannot grow. This ensures a shelf life of 3–6 months without freezing or preservatives.

🎨

Color, Texture and Yield

Gentle and uniform gravity drying preserves the original extrudate colour and prevents pellet surface cracking. Accuracy of ±0.5% directly protects yield — every 1% non-uniformity on a 75,000 t/year line means a loss of 750 tonnes of final product.

Application Areas

Which Products Is It Used For?

🐠

Floating Fish Feed

  • Lososide (losos, pastrmka)
  • Carp, tilapia, catfish
  • Morske akvakulturne vrste
  • Pellets 0.9–15 mm diameter
🐕

Dog and Cat Food

  • Kibble — dry dog food
  • Expanded granules for cats
  • Functional feed (diet, senior)
  • Premium and veterinary product range
🐡

Ornamental Fish Feed

  • Sitni granulat 0,5–3 mm
  • Flake feed for aquarium fish
  • Feed for cichlids and discus
  • Speciality products for exotic species
🦐

Shrimp and Crustacean Feed

  • Extra gentle handling required
  • High pellet fragility — gentle handling required
  • Slow-sinking formulas
  • Marine shrimp & freshwater shrimp
🌊

Specialised Aquaculture

  • Slow-sinking feed
  • Slow-release feed
  • Feed for larvae and juveniles
  • Medicated feed
🦜

Feed for Other Animals

  • Feed for birds and rodents
  • Feed for rabbits and hares
  • Functional snacks for pets
  • Tretovi i nagrade za dresuru
Technology Comparison

Counterflow vs. Belt Dryer

Parametar Counterflow (SE 14xx14) Belt Dryer
Flow principle Material and air in counterflow Air passes through belt from top/bottom
Energy efficiency ✓ Higher — air used to saturation limit ~ Lower — part of heat lost with exhaust
Outlet moisture uniformity ✓ ±0,5% ✗ ±2%
Space footprint ✓ Compact — vertical design ✗ Larger — horizontal belt layout
Maintenance ✓ Fewer moving parts ✗ Belt requires regular maintenance
Contamination ✓ Minimal — closed system ~ Possible — accumulation on belt
Pellet handling ✓ Gentle — gravity flow ~ Mechanical contact with belt
Suitability for premium feed ✓ Fish, pet food, aquaculture ~ Broader range of materials and sizes

Optimise Your Feed Line

Our engineering team will recommend the optimal dryer configuration for your capacity, feed type and available energy source. We are available for questions and technical consultations.

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