A three-phase, multiple-species, one-dimension model has been developed to simulate bacterial transport, growth, and metabolism processes involved in microbially enhanced oil recovery (MEOR) and to predict permeability modification that results from these microbial activities in porous media. Convection-dispersion equations and microbial kinetics are incorporated in the model system to characterize and quantify biomass production, product formation, and nutrient utilization in the MEOR process. Permeability modification is assumed to be due to both pore-surface retention and pore-throat plugging by bacterial cells.
The model has been applied to static (sand packs) and core-flooding (sandstone cores) experiments to describe microbial movement, metabolite production, and nutrient consumption during growth and metabolism and to estimate permeability reduction. Comparison between numerical solutions and experimental results indicated that the model does simulate the essential microbial kinetics of laboratory experiments and can be extended to provide numerical predictions for the purposes of design and evaluation of MEOR field projects.