LIQUID FLOW IN BIOFILM SYSTEMS

A model biofilm consisting of Pseudomonas aeruginosa, Pseudomonas fluo rescens, and Klebsiella pneumoniae was developed to study the relation ships between structural heterogeneity and hydrodynamics. Local fluid velocity in the biofilm system was measured by a noninvasive method of particle image velocimetry, using confocal scanning laser microscopy. Velocity profiles were measured in conduit and porous medium reactors in the presence and absence of biofilm. Liquid flow was observed with in biofilm channels; simultaneous imaging of the biofilm allowed the l iquid velocity to be related to the physical structure of the biofilm.