Current oil production technologies recover only about one-third to one-half of the oil originally present in an oil reservoir. Given current oil prices, even modest increases in tertiary recovery rates can prove to be fiscally attractive. Use of existing oil fields for tertiary recovery provides significant cost-saving over development of new sites, especially as oil prices increase and remaining undeveloped sites are likely to be in locations and geologic formations that are costly to develop.
Microbially enhanced oil recovery (MEOR) has historically been a technology marketed to industry with promises of increased tertiary oil recovery at a fraction of the price of other enhanced oil recovery processes (EOR), however to this point, increased oil production has been at best inconsistent and results of laboratory and field scale experiments and implementations have been conflicting. One mechanism for extraction we address in this proposal is the mobilization of oil due to microbial production of biosurfactants. The reduction in interfacial tension (IFT) through microbial secretions targets the portion of oil that remains entrapped in the host reservoir rock after primary and secondary recovery.
The proposed work uses a novel 3D pore-scale imaging technique (high-resolution computed microtomography, CMT), 2D micro-models, and 1D macro-scale column studies to elucidate basic level microbial and interfacial interactions and thus evaluate MEOR technology, specifically using in-situ microbially produced biosurfactants. We aim to identify the types of oil fields (tight or relatively high-permeability material, effect of mixed wettability) in which microbial surfactant-facilitated MEOR is likely to be profitable.
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