📋 Case Study

FCC Unit Regenerator Coke Burn Optimization (ExxonMobil Baytown)

Incomplete coke burn leading to catalyst metal poisoning and excessive CO/NOx formation

🏗️ Project Overview

Reduction of NOx emissions and catalyst deactivation in fluid catalytic cracking regenerator

🎯 Challenge

Incomplete coke burn leading to catalyst metal poisoning and excessive CO/NOx formation

🔧 Design Approach

O₂-enriched air injection with spatially resolved thermocouple grid and kinetic model-based burner zone staging

📐 Design Diagram

_coke = 0.82 g/g·min [O₂]^0.5[Coke] d[NO]/dt = 12 ppmv k_NO[N][O₂]^0.5 FCC Unit Regenerator Coke Burn Optimization

AI-generated project design illustration

📐 Key Calculations

Coke Combustion Rate

r_coke = k × [O₂]^0.5 × [Coke]

Result: 0.82 g coke/g cat·min

Target for full burn without hot spots

NO Formation Rate

d[NO]/dt = k_NO × [N] × [O₂]^0.5

Result: 12 ppmv

Trigger for ammonia injection dosing

📊 Results

NOx reduced by 63%, catalyst cycle life extended by 22%, regenerator temp variance <±8°C

💡 Lessons Learned

• •Spatial heterogeneity requires distributed sensing + model coupling
• •Kinetic inhibition by steam must be explicitly modeled

✅ Key Takeaways

• 1Spatial heterogeneity requires distributed sensing + model coupling
• 2Kinetic inhibition by steam must be explicitly modeled