The research objective of this award is to derive a fundamental biomechanical model capable of predicting and improving efficiency of water filtration and bioremediation. The approach is as follows. Microbial strains identified by the Department of Energy will be cultured in aqueous environment with ionic concentration matching that of the polluted waterways. Micro-characterization using atomic force microscopy will determine surface potential, intersurface forces, adhesion energy, and elastic modulus of single cells, surface roughness and zeta potential of sand grains etc. Macro-characterization using standard packed column tests will measure filtration efficiency for different water flow rates and temperature. Such information will be fed into a new model of adhesion-detachment of cells, liquid-solid interaction, and statistical retention of cells on sand substrates. Based on quick single cell characterization, macroscopic filtration behavior of a myriad of bacterial strains can ultimately be predicted and tested.
If successful, the benefits of this research will include (i) prediction of fate and transport behavior of microorganisms in porous media, (ii) design, evaluation and feasibility studies of in-situ or enhanced subsurface bioremediation and bioaugmentation, (iii) effective implementation of engineered (sand filters) or natural (bank filtration) filtrations processes for water treatments, (iv) migration of pathogens in drinking water supplies and microbial enhanced oil recovery. The research results will in a long run contribute to resolving the increasing need for clean drinking water in the 21st century with growing world population and drastic global climate change.
