Beschreibung:
Water injection, especially seawater, into the oil reservoirs is one of the traditional but practical solutions to maintain or increase pressure, sweep mobile oil, and release capillary trapped oil by adding chemical agents. However, this method also has its problems, among which precipitation and deposition of inorganic scales in the reservoir and near-wellbore which leads to a reduction in well injectivity/productivity, is of particular importance due to the imposition of high operating costs. In this study, the MATLAB Reservoir Simulation Toolbox (MRST) is coupled with a geochemical module (i.e., IPHREEQC) to develop a fully reactive module (ad-scale) to assess the risk of this operational challenge more accurately. The performance of the developed module is validated using laboratory data and several well-known benchmarked examples. Then, the ad-scale was used to assess the risk of scale deposition during waterflooding experiments. The results demonstrate that calcite dissolution occurs during sulfate-rich water injection; on the other hand, dolomitization and anhydrite precipitation happen; this process leads to porosity and permeability reduction. Simulation results show the most porosity reduction in the 1FW:3SW mixing ratio of injecting water (formation water and seawater); porosity could reduce up to 35%; also, the harmonic average of the permeability could reduce between 15% to 35% based on the permeability alteration model