This research offers a fresh viewpoint on modeling CO2 injection into shale oil fields for prospective EOR and geological storage. The effectiveness of several injection procedures to promote oil recovery and CO2 storage in the Eagle Ford shale reservoir is investigated using a conceptual knowledge of oil recovery processes combined with field-reported data. Continuous gas injection of dual lateral well pattern (two laterals at different depths), and Huff-n-Puff injection (single well changes between producer and injector with soaking interval) are the injection techniques examined. The findings of this research are utilized to propose an optimal injection strategy that maximizes CO2 recovery and storage in the field under investigation. We developed a compositional numerical simulation model for a pilot test well in Eagle ford. The fluid composition, rock parameters, and hydraulic fracture characteristics of the considered well were updated to match the production data. The simulation runs are done using the history matched model to optimize the injection settings of each method. The performance of each injection technique, is evaluated using the optimal model for each approach. The performance of the proposed injection procedure outperformed the other techniques in increasing oil recovery and CO2 storage. After an optimization of the designed well models, the proposed injection procedure still outperformed traditional EOR in CO2 storage, oil recovery, and net present value (NPV). This research presents and evaluates innovative gas injection techniques in shale reservoirs, as well as give insights into gas injection in shale reservoirs, in order to improve production and minimize greenhouse gas emissions by improving carbon storage capacity.
Shale oil, exist in unconventional oil formations, accounts for one-third of the U.S. onshore oil production (Amadeo). The Energy information administration (EIA) reported that it is because of the production from shales, that the US has become the largest crude oil producer in the world. In turn, this increase of domestic oil production has enabled the U.S. to reduce its dependance on foreign oil, which allows the U.S. to be able to store more of its own oil and reduced oil and gas prices due to the increase of supply (Amadeo).