EN
The mixing and mass transfer have been investigated in industrial bioreactors of capacity 10,30,50 and 150 m cu.meter. used for citric acid fermentation.Hydrodynamic parameters were examined on water using mineral acid as a trace. Volumetric <mass transfer coefficient> (kLa) was determined by balance method. It was found that the examined <bioreactors> have similar <hydrodynamic parameters> lespite their different capacities. The differences were found in maximum values of kLa which coresponded to the citric acid yield and productivity.