Mixing and oxygen transfer in conventional stirred fermentors

A set of experiments has been performed in an industrial 112 m3 fermentor in order to get a complete map of oxygen concentration and temperature distribution in the system. Five fermentations of non‐Newtonian broths of two different strains, in various operating conditions, were examined. A simple model has been developed which takes into account both the mixing and the mass‐transfer properties of the fermentor, and a dimensionless parameter has been identified which is sufficient to characterize the oxygen axial distribution in the reactor in any operating condition.