Case Study: Hybrid Solar & Heat Pump Drying Room for Seafood Processing with Daxwell

Executive Summary

1. Challenges in Traditional Seafood Drying

Seafood (shrimp, fish, squid) is a high-value commodity but extremely sensitive to the drying process. According to environmental control standards, dried seafood requires precise moisture control (around 25-30% RH for storage) and specific drying temperatures (27-32°C) to prevent mold, oxidation, and protein degradation.

Traditional methods are facing severe limitations:

• Open Sun Drying: 100% weather-dependent, takes 3-5 days, high risk of contamination (dust, insects), uneven moisture, and severe mold risks during the rainy season.
• Electric Resistance Dryers: Extremely high energy consumption (OPEX can account for 40-50% of product cost), making it economically unviable for small enterprises.
• Quality Demands: Export markets and supermarkets demand strict food safety standards, uniform moisture, and preserved natural color.

The challenge for DeAir was to engineer a "tailor-made" drying solution for small-scale operations: reasonable CAPEX, ultra-low OPEX, premium product quality, and a rapid ROI of 12-18 months.

2. The Breakthrough: Hybrid Solar & Heat-Pump Drying Room

DeAir is proud to introduce the hybrid drying room, combining two powerful energy sources: free solar thermal energy and energy-efficient heat-pump technology. This is the sustainable trend for the seafood processing industry in Vietnam.

Intelligent Hybrid Operation Principle

The system operates smartly, automatically prioritizing and switching between energy sources:

• Sunny Daytime: The solar thermal system absorbs radiation, heating the air to 40-60°C. This hot air is ducted into the drying chamber, while the Daxwell heat pump runs in support mode to maintain exact humidity levels.
• Nighttime or Rainy Days: The system automatically switches to standalone Heat-Pump mode. The Daxwell machine utilizes heat-pump technology to recycle condensation heat, saving 40-50% electricity compared to resistance heaters.
• Parallel Operation: In low-light conditions, both systems run simultaneously to maximize throughput and shorten drying cycles.

Daxwell Heat-Pump Dryer - The Heart of the System

Daxwell is an industrial dryer manufactured by DeAir, featuring a PLC control cabinet and an intuitive HMI screen. Unlike basic machines, Daxwell delivers:

• Precise Control: Custom drying curves for specific seafood (shrimp, fish, squid) with temperatures ranging from 25-80°C.
• Visual Monitoring: The HMI displays real-time temperature, humidity, and remaining cycle time.
• Data Logging: Records drying history, supporting traceability and quality certifications (HACCP, ISO 22000, ESG).

You can explore more about Daxwell's applications in our article: ESG-Standard Mango Drying: A Sustainable Solution with Daxwell Dryers.

3. On-Site Installation & M&E Execution

DeAir strictly adheres to the ISO 9001:2015 quality management system during every phase of deployment, ensuring quality and schedule compliance.

• Insulated Chamber: PU/PIR panels (50-100mm thick) ensure airtightness and minimize thermal loss.
• Solar Integration: Solar collectors are positioned for maximum sun exposure, connected via insulated ducts.
• Daxwell Installation: Power connection (1-phase 220V or 3-phase 380V), air supply/exhaust ducts, and condensate drainage.
• Stainless Steel Trolleys: SUS304 mesh trays optimize airflow and ensure food safety hygiene.

4. Commissioning: Testing, Calibration & Handover

The Commissioning phase is the ultimate proof of DeAir's engineering prowess. We don't just turn on the machine; we meticulously calibrate the microclimate.

• Shrimp Drying Curve: 45-50°C, 8-12 hours, final moisture 25-30%.
• Fish Drying Curve: 40-45°C, 12-18 hours, final moisture 25-30%.
• Sensor Calibration: Cross-checking internal sensors with master measuring devices (Error margin < ±2%).

5. Achieved Results & Real-World Value

• Premium Quality: Seafood retains its natural color, no darkening like sun-drying. Meets strict food safety hygiene (no dust/insects).
• Massive OPEX Reduction: Cuts electricity costs by 60-70% compared to pure electric resistance drying.
• Weather Independence: Active 24/7, reducing drying time from 3-5 days down to 8-18 hours.
• Fast ROI: Estimated payback period of just 12-18 months.

6. Infographic: Drying Methods Comparison

7. Scaling Up: From Households to Export Enterprises

Large-Scale Model: 40m² Drying Room (3m Ceiling)

Beyond small-scale solutions, DeAir provides industrial drying rooms for export enterprises. A prime example is our 40m² drying room (3m ceiling height) for the rattan and bamboo export industry.

• Capacity: Daxwell DX-600S / DX-1200D models.
• Volume: 120m³, capable of drying 500-1000kg per batch.
• Control: Centralized PLC, remote BMS monitoring.

8. Frequently Asked Questions (FAQ)