ToolFusion Chemical
ToolFusion Chemical
📋 Case Study

Bioethanol Dehydration Using Pervaporation Membranes

Azeotropic limitation of conventional distillation causing 30% energy penalty

🏗️ Project Overview

Corn-based ethanol plant in Iowa upgrading fuel-grade ethanol (95%) to fuel-blend grade (99.8%+)

🎯 Challenge

Azeotropic limitation of conventional distillation causing 30% energy penalty

🔧 Design Approach

Hybrid system: extractive distillation (using ethylene glycol) followed by hydrophilic PVA composite membrane pervaporation

📐 Design Diagram

Bioethanol Dehydration Using Pervaporation Membranes ⚠ Azeotropic limitation: 30% energy penalty in conventional distillation Extractive\nDistillation\n(Ethylene Glycol) PVA\nMembrane α = 12,500\nP = 1.2 kg/m²·h·kPa Feed\n(95% EtOH) Permeate\n(H₂O-rich) Retentate\n(>99.9% EtOH) −30%\nEnergy

AI-generated project design illustration

📐 Key Calculations

Pervaporation Separation Factor (α)

(y_water/y_ethanol)/(x_water/x_ethanol)
Result: 12,500
Indicates selectivity

Permeance (P)

J/(Δp)
Result: 1.2 kg/m²·h·kPa
Determines required membrane area

📊 Results

Energy use reduced by 41%; final ethanol purity 99.92%; ROI achieved in 2.8 years

💡 Lessons Learned

  • •Membrane fouling accelerated by glycol carryover—required guard bed
  • •Temperature swing during feed preheating improved flux stability

✅ Key Takeaways

  • 1Membrane fouling accelerated by glycol carryover—required guard bed
  • 2Temperature swing during feed preheating improved flux stability