BioReactorDesign Simulation Report
Process-bigraph wrapper for BiRD: 0D bioreactor models with Higbie kLa, Monod kinetics, and temperature-dependent Henry's law. Three E. coli fermentation scenarios — from 2 L bench to 10,000 L production — demonstrating scale-up mass transfer challenges.
E. coli Lab-Scale Batch
2 L bubble column — exponential growth, O₂ crash
A benchtop bubble column (2 L) growing E. coli K-12 at 37°C in minimal medium. With moderate aeration (0.5 vvm), the culture initially enjoys excess dissolved oxygen. As biomass doubles every ~60 min (μ_max = 0.7 h⁻¹), the oxygen uptake rate overtakes the mass transfer capacity, causing a characteristic DO crash. This is the classic aerobic E. coli batch profile seen in teaching labs.
3D Reactor Geometry
Time-Series Dynamics
Architecture & Document
Bigraph Architecture
PBG Composite Document
E. coli High-Cell-Density (Stirred Tank)
50 L stirred tank — high OD, impeller-enhanced kLa
A 50 L stirred-tank bioreactor growing E. coli BL21 for recombinant protein production at 37°C. The Rushton impeller (200 W) dramatically improves kLa, enabling much higher biomass than a bubble column alone. Starting from a higher inoculum (OD≈ 1), the culture reaches high cell density while the combined agitation + sparging maintains dissolved oxygen above the critical threshold for aerobic metabolism.
3D Reactor Geometry
Time-Series Dynamics
Architecture & Document
Bigraph Architecture
PBG Composite Document
E. coli Industrial Scale-Up
10,000 L airlift — mass transfer bottleneck at scale
An industrial airlift reactor (10,000 L) scaling up E. coli fermentation at 37°C. Despite 50 L/min of air, the large vessel diameter yields low superficial gas velocity and poor kLa. The culture quickly becomes oxygen-limited, demonstrating the classic scale-up problem: mass transfer that was adequate at bench scale becomes the bottleneck at production scale. Growth rate collapses as DO drops below the critical concentration.
3D Reactor Geometry
Time-Series Dynamics
Architecture & Document
Bigraph Architecture