Enhanced biodegradation by hydraulic heterogeneities in petroleum hydrocarbon plumes

摘要: In case of dissolved electron donors and acceptors, natural attenuation organic contaminant plumes in aquifers is governed by hydrodynamic mixing microbial activity. Main objectives this work were (i) to determine whether aerobic anaerobic biodegradation porous sediments controlled transverse dispersion, (ii) elucidate the effect sediment heterogeneity on biodegradation, (iii) search for degradation-limiting factors. Comparative experiments conducted two-dimensional microcosms. Aerobic toluene later ethylbenzene degradation Pseudomonas putida strain F1 was initially followed a plume developing from oxic anoxic conditions under steady-state mixing-controlled conditions. Competitive then initiated introduction denitrifying Aromatoleum aromaticum EbN1. homogeneous sand, clearly dispersive mixing. Similarly, conditions, activity located at plume's fringes. Sediment caused flow focusing improved reactants. Independent accepting process, net always higher heterogeneous setting with calculated efficiency plus 23-100% as compared setup. Flow reactive transport model simulations performed order interpret evaluate experimental results.