Project Summary (1995-2000)

The overall goals of this research project are to study biodegradation of toxic organics and organo-metallics in microbial biofilms by evaluating transport mechanisms of contaminants into and out of the biofilm, spatially and quantitatively characterizing the microbial populations in the biofilm, and applying the results obtained to full-scale treatment systems. A variety of azo dyes are being used as the test toxic substances. Specific aims of the research are to characterize the physical properties of the biofilm in and without the presence of the toxicant, characterize the diffusion boundary layer, evaluate transport mechanisms and biodegradation kinetics for azo dyes, determine the location and number of azo dye degrading microorganisms in biofilms, evaluate the impact of seeding aerobic biofilm reactors with azo dye degrading microorganisms, evaluate transport mechanisms and biodegradation kinetics for toxic metal complexed azo dyes, and evaluate the scale-up of microscale results to full scale. The end result should be a much clearer understanding of the mechanics of biofilm treatment systems and allowing for better design of processes for treatment of toxic wastes.