Evaluating the Potential of Smart Water Flooding in Pre-Salt: From Lab Results to Field Scale Evaluation Through a Simulation Study

Abstract

Abstract The effectiveness of injecting CuCl2 enriched seawater, a smart-water EOR method also known as metallic-tuned water injection, was evaluated in a pre-salt field. This was achieved through the implementation of laboratory results on reservoir simulation, which was used to assess the performance of such EOR technique in terms of oil recovery and water injection efficiency. The study aims to provide insights into the potential benefits and limitations of smart waterflooding in pre-salt at field scale. Core flooding experiments were conducted to estimate the incremental recovery through the injection of metallic tuned water (MTW). Relative permeability curves were obtained for both seawater/oil and MTW/oil under reservoir conditions. To evaluate the effects of tertiary recovery injection with metallic (copper) tuned water at field scale, it was simulated using EclipseTM300. First, the history match and forecast were simulated up to the start of the MTW injection. Once the pressure and saturation conditions were estimated, the relative permeability curves obtained in the core analysis were modified and the effects of the MTW injection were simulated. Three core flooding experiments under reservoir condition with reservoir rocks and reservoir oil samples from pre-salt presented incremental oil recovery in all the cases. Experiment 1 presented a typical recovery factor for pre-salt fields of 23.4% with conventional method of desulphated seawater (seawater with reduced sulfate - 100 ppm) and 28.8% of incremental RF with copper solution, reaching a final RF of 52.2%. Experiments 2 and 3 presented 24.9% and 20.0% of RF with desulphated seawater and incremental recoveries of 6% and 30% with MTW, respectively. Relative permeabilities of both desulphated sweater/oil and MTW/oil were obtained to be used into the reservoir model. Corroborating the laboratory data, the simulation study showed evidence of increased oil recovery. Consequently, it becomes essential to bridge the gap between lab-scale results and field-scale implementation.