In Situ Production of Microbial Fe Nanoparticles for Blockage Removal and Enhanced Oil Recovery

Abstract

By applying biotechnology and nanotechnology in the oil industry, this study proposes and confirms a novel strategy of in situ microbial nanoparticle production enhanced oil recovery (IMNPEOR) through the in situ production of bio-nanoparticles (BNPs) by a microbial iron reduction process to improve oil recovery. A group of iron-reducing strains of Shewanella chilikensis CD-4 were used to investigate the transformation of poorly crystalline ferrihydrite into Fe BNPs, which were characterized by scanning electron microscopy, transmission electron microscopy, nanoparticle size and ζ potential, Fourier transform infrared spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and vibrating sample magnetometer analyses. The BNPs produced by S. chilikensis CD-4 were confirmed as uniform spherical magnetic Fe nanoparticles of size 20–30 nm. Through core drive simulation of microbial in situ production of nanomaterials for oil displacement experiments, the oil–water interfacial tension was reduced by 30%, core permeability was increased by 62.7%, and crude oil recovery was increased by 15.55%. IMNPEOR combined the advantages of microbial enhanced oil recovery (EOR) and nanofluid EOR, providing an inexpensive and environmentally friendly method of enhanced oil recovery and blockage removal, making a breakthrough in microbial enhanced oil recovery.