A state of the art review to develop novel workflow for microscopic scale understanding of advanced water flooding mechanisms in carbonates

Advanced water flooding processes through tailoring of injection water salinity and ionic composition are becoming an attractive proposition for improved and enhanced oil recovery (IOR/EOR) in carbonate reservoirs. The importance of microscopic and submicroscopic scale investigations on such optimized chemistry water injection processes in carbonates has not received wide attention. To fill this existing knowledge gap, we provided a comprehensive review on the state-of-the-art microscopic and sub-microscopic scale experimental methods in this study. A new workflow has been developed for advanced flooding processes by including different interfacial instruments and many advanced techniques in combination with several high-resolution imaging and spectroscopic tools. The practical applicability of different components in the workflow and their implications on advanced water flooding processes are demonstrated by using selected examples from published data. These results pointed out that atomic to molecular scale interactions occurring at both fluid-fluid and rock-fluids interfaces together play an important role to impact oil recovery and mobilization in advanced water floods. The proposed workflow can also be applicable to understand the fundamentals of several other recovery processes, but not limited to the following: secondary water injection, low salinity water flooding in sandstones, and other enhanced oil recovery processes involving surfactant chemicals and nanoparticles. A framework on desired methodology has been provided to describe how to sequentially progress these atomic to molecular scale data measured at interfaces to core and field scales (atomic - > molecular - > pore - > core - > well bore - > near wellbore - > reservoir). The three major path forward steps on: (1) upscaling of measured atomic to molecular scale data into models, (2) pushing the technology limits of techniques to perform measurements at appropriate reservoir conditions, and (3) bridge existing knowledge gap in the industry by acquiring scientists from other disciplines are suggested for successful implementation of proposed workflow to perform fundamental research studies at both fluid-fluid and rock-fluids interfaces.