Industrial Steam Coils for Rotary Sugar Dryers

Steam coils are a proven and reliable solution for hot air generation in rotary sugar dryers, where continuous operation, stable thermal output, and resistance to fouling are critical. Designed specifically for the sugar processing industry, these industrial steam heating coils use saturated steam to raise process air temperature efficiently while withstanding dusty environments containing sugar fines.

1. General Information

• Application: Hot air generation for rotary sugar dryer

• Industry: Sugar processing

• Operation mode: Continuous industrial duty

• Heating method: Indirect air heating using saturated steam

Steam coils are installed in the air duct upstream of the dryer to heat large volumes of air uniformly, ensuring stable drying performance and consistent product quality.

2. Process Conditions

The steam coil is engineered to meet the following operating conditions:

• Air flow rate: 3,000 Nm³/h

• Air inlet temperature: ~30 °C

• Required air outlet temperature: 120–130 °C

• Heating medium: Saturated steam

• Available steam pressure: 3 bar(g)

• Ambient conditions: Dusty environment with sugar fines

Low-fouling design and robust construction are essential due to airborne sugar particles that can accumulate on heat transfer surfaces.

3. Steam Coil Technical Specifications

a) Dimensions & Configuration

• Frontal (face) area: 0.42–0.45 m²

• Typical dimensions: 700 mm × 600 mm

• Coil depth: 250–300 mm

• Number of tube rows: 6 rows

• Tube outside diameter: 5/8” (15.9 mm)

• Tube layout: Staggered arrangement

• Fin type: Aluminum fins

The staggered tube configuration improves heat transfer efficiency while maintaining acceptable air-side pressure drop.

b) Fin Density (Anti-Fouling Design)

• Fin density: 6–8 FPI (fins per inch)

A low fin density is deliberately selected to:

• Minimize clogging caused by sugar dust

• Extend cleaning intervals

• Maintain stable thermal performance over long operating periods

4. Materials of Construction

Material selection ensures durability, corrosion resistance, and compatibility with steam service:

• Tubes: Carbon steel or aluminum (project-specific selection)

• Fins: Aluminum

• Headers / manifolds: Carbon steel or stainless steel

• Casing / frame: Carbon steel

All materials are suitable for continuous industrial operation in sugar processing plants.

5. Steam & Condensate Connections

• Steam inlet connection: 1” (threaded or flanged)

• Condensate outlet connection: 1” (threaded or flanged)

The steam coil is designed with:

• Proper internal condensate drainage

• Installation with a slight slope toward the condensate outlet

• Compatibility with steam traps and condensate recovery systems

This design prevents water hammer and ensures stable heat transfer.

6. Thermal Performance Requirements

• Required heating capacity:

• Minimum: 70 kW

• Preferred operating range: 80–90 kW

• Maximum air-side pressure drop:

• ≤ 250 Pa

• Preferred ≤ 200 Pa

• Steam-side design pressure:

• Minimum: 4 bar abs

• Preferred: 6 bar abs (additional safety margin)

These parameters ensure efficient air heating without excessive fan power consumption.

7. Advantages of Steam Coils in Sugar Dryer Systems

• High thermal efficiency using low-pressure saturated steam

• Reliable continuous operation

• Low fouling design suitable for dusty sugar environments

• Simple integration into existing air handling and duct systems

• Long service life with minimal maintenance

Conclusion

Industrial steam coils designed for rotary sugar dryers provide an efficient, robust, and cost-effective solution for hot air generation in sugar processing plants. With optimized fin density, appropriate materials, and carefully engineered thermal performance, these coils ensure stable drying temperatures, low pressure drop, and reliable long-term operation even in dusty conditions.