4.4 Comparative trials: Traditional vs. REHD energy consumption

Here’s a detailed overview of comparative trials between Traditional Hydrodistillation (HD) and Reduced-Energy Hydrodistillation (REHD) with respect to energy consumption:


1. Introduction

Comparative trials evaluate energy efficiency, extraction time, yield, and oil quality between traditional and modern REHD methods. These trials help producers select methods that reduce costs, preserve oil quality, and minimize environmental impact.


2. Energy Consumption Comparison

ParameterTraditional HDREHDObserved Difference
Energy SourceDirect fire, electric heatersOptimized boilers with insulation, heat recoveryREHD uses 30–50% less energy
Operating TemperatureHigh (100–110°C for extended periods)Moderate (70–90°C with steam/pressure optimization)Lower temp reduces fuel consumption and preserves thermolabile compounds
Extraction Duration4–8 hours for flowers, up to 12–24 hours for wood2–4 hours for flowers, 6–12 hours for woodShorter distillation → lower energy use
Steam UsageContinuous high-volume steamControlled steam flow with recirculationREHD reduces wasted steam and energy
Heat RecoveryMinimalIntegrated from condensate and flue gasesREHD recycles 10–25% of energy
Yield per Energy UnitModerateHigherREHD achieves more oil per kWh or kg of fuel

3. Key Observations from Trials

  1. Energy Efficiency
    • REHD consumes significantly less fuel/electricity due to lower temperature, shorter duration, and steam recycling.
  2. Oil Quality
    • REHD produces better retention of volatile and heat-sensitive compounds, especially in aromatic flowers (e.g., Ylang-Ylang) or resinous wood (Agarwood).
  3. Water Usage
    • REHD uses less water per batch due to reduced steam flow and condensate reuse.
  4. Economic Impact
    • Reduced energy consumption → lower operational cost per liter of oil.
    • Faster cycles → higher throughput and ROI for SMEs.

4. Sample Comparative Trial Data (Illustrative)

CropMethodEnergy Consumed (kWh/kg oil)Yield (mL/kg plant)Extraction Time (hours)
Lavender FlowersTraditional HD1201.25
Lavender FlowersREHD651.32.5
Agarwood ChipsTraditional HD4500.818
Agarwood ChipsREHD2500.8510

Observation: REHD reduces energy consumption by ~45–50%, slightly increases yield, and cuts extraction time nearly in half.


5. Practical Implications for SMEs and Industry

  • SMEs: Can implement small REHD modules to reduce fuel bills and produce premium-quality oils.
  • Large-scale operations: REHD integration with heat recovery and condensate loops maximizes energy savings.
  • Sustainability: Lower energy footprint aligns with eco-certifications and reduces carbon emissions.

6. Visual / Infographic Concept

Title: “Comparative Trials: Traditional HD vs. REHD Energy Consumption”

  • Side-by-side layout:
    1. Traditional HD: high steam usage, long extraction, high kWh/kg oil
    2. REHD: optimized steam, heat recovery, shorter extraction, lower kWh/kg oil
  • Include graphs showing energy consumption vs. yield, icons for fuel/water savings, and extraction time.
  • Optional: show quality retention improvement (volatile compound preservation).

I can create a polished infographic showing energy consumption comparison between Traditional HD and REHD, highlighting energy savings, shorter extraction time, and improved oil quality for training or presentations.

Do you want me to make that next?