Abstract: A centrifugal film bioreactor useful for processing both shear sensitive and shear requiring or tolerant cells. A liquid phase is directed upward in a guide tube to rotating truncated conical surfaces which transport the liquid phase across their surfaces. After leaving the conical surfaces, the liquid passes through a gaseous phase and may contact the wall of the fermentation vessel and then combine with the downward moving liquid phase in the lower part of the fermentation vessel, where it circulates. The maximum entrainment of the gaseous phase into the liquid phase occurs while the liquid phase is passing through the gaseous phase. Different configurations of guide tube propellers and fermentation vessel, allow for processing of different shear tolerant cells.

Abstract: A device based on rotating surfaces for promoting highly efficient molecular diffusive transfer between gases and liquids is described. Said transfer is achieved by generating a thin film of liquid which flows on a rotating surface, thereby exposing a large area of flowing liquid to the gaseous phase. This device is especially useful in promoting efficient molecular transfer of gases with low solubility in the liquid, e.g., oxygen into an aqueous phase in conventional aerobic fermentation vessels. The principle of this system can be employed in the reverse direction of transfer, for gases leaving the liquid phase, such as occurs in stripping, defoaming and deodorization. Of special value is the prevention of foaming, a common problem in the operation of conventional fermentation processes which occurs as the molecular transfer takes place.