Effects of shear detachment on biomass growth and in situ bioremediation

The dispersed growth model incorporating Monod kinetics has often been appl ied to simulate enhanced in situ bioremediation of contaminants. The disper sed growth model might not adequately address the impacts of the growth of large bacterial populations that can often have the unwanted effect of clog ging the porous media. Two mechanisms that could affect model predictions o f biomass are biofouling and biomass detachment due to shear stress. A math ematical model was developed to evaluate the potential impact of shear deta chment on biomass distribution and the prediction of contaminant biodegrada tion by comparing the impact of both shear detachment and biofouling togeth er with that of biofouling alone. The results of this examination can aid i n designing a system for in situ bioremediation using computer simulations and in evaluating a system's ability to meet remediation goals. The model s imulations indicate that shear detachment of biomass can be an important pr ocess to include in model simulations used to predict the effectiveness of a bioremediation system and the time before significant clogging occurs.