Theory 56/Bioprocess Engineering
Yield Is an Oxygen Ratio
The claim
Aerobic yield is set by the ratio of oxygen transfer capacity to oxygen demand rather than by dissolved oxygen setpoint.
01The mechanism
Demand rises with biomass; transfer capacity is fixed by the reactor, so the ratio falls as the culture grows and limitation appears abruptly.
02Predictions
- P1Yield should track the ratio.
- P2Setpoint alone should mispredict across densities.
03Refutation
Yield tracking setpoint would remove the transfer term.