Abstract: A process and system for cultivating adhesive cells in a packed bed of solid cell matrix is disclosed. Adhesive cells are adhered to a solid cell matrix, preferably ceramic particles, and packed in a cell culture tank to form the packed bed. The culture medium is circulated through the packed bed in a direction. The circulating of the culture medium is then stopped and the direction of the medium being circulated is reversed. This periodic switching of the direction of the culture medium reduces channelling of the culture medium. The bottom or head of the culture tank can also contain a separator to trap any bubble existing in the culture medium or to trap any quantity of cell matrix possibly running out from the culture tank.

Abstract: There is provided between a concentrate tank and a membrane filter a circulating line which consists of a feed line and a return line. It is also possible to use an ultrafilter as the membrane filter. There is provided a leveling tube connected by respective pipes to the concentrate tank at top and bottom portions thereof, respectively. A buoy floats within the leveling tube and a position of this buoy is detected by means of transparency of the leveling tube itself or photosensors in order to detect a degree of concentration of the culture fluid progressing within the concentrate tank. There may be provided multi-stage circulating lines each connecting the associated concentrate tank to the associated membrane filter so that the culture fluid can be transferred during the process of concentration from the stage of the largest volume treatment to the state of the least volume treatment in order to concentrate the culture fluid more efficiently.