(531f) Enhanced Oxygen Transfer and Cell Growth in a Continuous Rotating Bioreactor

A continuous bioreactor has been designed to increase cell growth rate and overall productivity by improving oxygen delivery. The operation of this bioreactor is similar to a roller bottle, but it can be operated either in batch or continuous mode, with inlet flows available to provide medium and oxygen to the bioreactor. The new design improved oxygen transfer in the bioreactor by at least two fold. The higher oxygen transfer performance was achieved by using a spiroid tube attached to the outer wall of the bioreactor, thereby increasing the gas-liquid interfacial surface.

Oxygen measurements were conducted to determine oxygen transfer in the bioreactor with and without the spiroid at different operating conditions. In addition, mathematical models were established to simulate the oxygen transfer in the system and to calculate the volumetric mass transfer coefficients (k_La) in both chambers and the spiroid tube at different operating conditions. Growth curves for E. coli with and without the spiroid were measured to confirm improvement in oxygen transfer.

Key words: continuous bioreactor, oxygen transfer, cell cultivation, spiroid