📋 Case Study

Industrial Park Co-Location: Steel Mill Waste Heat Integration

High-temp (200°C) low-grade waste heat integration without compromising stack lifetime

🏗️ Project Overview

3.2 MW alkaline electrolyzer co-located with blast furnace in Duisburg, Germany

🎯 Challenge

High-temp (200°C) low-grade waste heat integration without compromising stack lifetime

🔧 Design Approach

Two-stage thermal recovery: preheated feedwater via shell-and-tube exchanger + low-pressure steam injection into electrolyte loop

📐 Key Calculations

Feedwater Preheat ΔT

T_out - T_in
Result: 85°C
Reduces electrical energy demand by 11%

Steam Injection Mass Flow

Q_waste / h_fg
Result: 124 kg/h
Maintains optimal KOH concentration at 28 wt%

📊 Results

14.3% reduction in specific energy consumption (4.1 kWh/Nm³); 22% lower CAPEX via shared infrastructure

💡 Lessons Learned

  • Steam quality critical—must be <1 ppm TDS
  • Alkaline stacks tolerate wider temperature swings than PEM
  • Shared emergency shutdown logic essential

Key Takeaways

  • 1Steam quality critical—must be <1 ppm TDS
  • 2Alkaline stacks tolerate wider temperature swings than PEM
  • 3Shared emergency shutdown logic essential