Evaluation of O₂ and CO₂ transfer coefficients in a locally integrated tubular hollow fiber bioreactor

We have studied the transfer coefficients for O₂ transport to and CO₂ removal from a model cell-free system using microporous hydrophobic hollow fibers axially placed along a tubular bioreactor for ethanol production with immobilized yeast in the shell. In this locally integrated bioreactor, O₂ and CO₂ transfer rates depend strongly on the shell side liquid flow rate; O₂ flow rate in the fiber bore influences O₂ transport only at very low flow rates. Diffusion of CO₂ does not affect O₂ transport. Local and overall O₂ and CO₂ transfer coefficients have been determined for a wide range of Reynolds Numbers. The efficiency of such transfers has been demonstrated for alcohol fermentation.