統合的な微細構造評価とin-situ比抵抗モニタリングを用いたシルル紀ドロマイト層におけるCO2貯留の時間依存評価

Unofficial AI-generated summary based on the public title and abstract. Not an official translation.

🔬研究者:炭酸塩岩貯留層におけるscCO2-岩石-ブライン反応と比抵抗モニタリングの実験的知見を提供する。

🏢実務担当者:CCS/CCUSパイロットのモニタリング設計や長期貯留安全性評価に活用できる実証データを示す。

🏛政策担当者:CCS/CCUSのMRV・貯留 permanence 評価制度設計の基礎的エビデンスとして参照可能。

Understanding long-term CO2 storage behavior in carbonate formations is critical for advancing carbon capture and storage (CCS) and carbon capture, utilization, and storage (CCUS) technologies. This study presents an integrated experimental and petrophysical workflow designed to evaluate geochemical alteration and in-situ monitoring mechanisms under reservoir-representative conditions. The approach developed here will be of great value in pilot monitoring wells for CCS and CCUS projects. This study contributes to improving long-term CO2 storage in CCS and CCUS projects. The study is divided into two parts. The first part focuses on micro-scale characterization of samples from the Monroe well (DOE CarbonSAFE samples) and BEG samples. The BEG samples are cylindrical with a 1 cm diameter, while the Monroe samples are cubic, measuring 1 cm. In this study, the samples were initially analyzed using thin sections, micro-CT imaging, and porosity measurements. A 20 wt.% NaCl solution (200,000 ppm NaCl) was used as the brine. The seven samples were aged in static batch reactors at 120 °C and 2,000 psi for 6 months. Changes were evaluated using porosity, microporosity, pre- and post-ICP, pre- and post-ion chromatography, pre- and post-XRD, and pre- and post-SEM analyses. The second part of the study utilized the PLS-400 petrophysical laboratory system to analyze in-situ resistivity monitoring and evaluate its impact on long-term CO2 storage. The experimental workflow was applied to four core samples: H3, H4, S06465, and S06468. Sample H3 was collected from a depth interval of 10,673.5-10,674 ft, H4 from 10,721-10,721.5 ft, S06465 from 9,742 ft, and S06468 from 9,652 ft. The results were analyzed using Geochemist's Workbench software to evaluate long-term supercritical CO2 (scCO2) storage behavior, chemical speciation changes, and reactions among the rock, brine, and scCO2. Post-reaction brine chemistry showed changes in dissolved-ion concentrations after scCO2-brine-rock interaction, indicating carbonate/dolomite dissolution and coupled precipitation–dissolution reactions under high-salinity brine conditions. Pore combination modeling was performed using the PLS-400 system to characterize pore structure before and after exposure to scCO2. In-situ resistivity measurements were conducted under both 100% brine saturation and partial saturation conditions (approximately 30% brine and 70% scCO2). Measurements were performed at 120 °C to simulate reservoir conditions, and resistivity was continuously monitored for 10 days at 3,500 psia. In-situ resistivity monitoring proved to be an effective tool for developing scalable models applicable to CCUS, CO2-enhanced oil recovery (CO2-EOR), and foam-assisted CO2 huff-and-puff processes. The results support improved oil recovery strategies and contribute to the economic feasibility of CCUS technologies under U.S. Section 45Q tax incentives. This integrated and novel workflow enhances pore-scale understanding of mineralization, precipitation, and dissolution mechanisms, providing invaluable insights into the processes that control both hydrocarbon recovery and long-term CO2 storage capacity.

• semanticscholar https://doi.org/10.2118/233810-msfirst seen 2026-10-17 05:18:29 · last seen 2026-11-06 05:32:11