Microbial Mineralization of Montmorillonite in Low-Permeability Oil Reservoirs for Microbial Enhanced Oil Recovery

Abstract

Microbial mineralization is ubiquitous in the natural environment. Microbes in low-permeability reservoirs are able to facilitate alteration of the structure and phase of the Fe-poor minerals by reducing Fe(III) and inhibiting clay swelling, which is still poorly studied. This study aimed to reveal the interaction mechanism between Fe(III)-reducing bacterial strains and Ca-montmorillonite under anaerobic conditions and to investigate the extent and rates of Fe(III) reduction and phase changes with their activities. Application of Fe(III)-reducing bacteria will provide a new way to inhibit clay swelling, to elevate reservoir permeability, and to reduce pore throat resistance after water flooding for enhanced oil recovery in low-permeability reservoirs.