Geochemical impact of oxygen on siliciclastic carbon storage reservoirs

摘要: Abstract In planning for large-scale CO 2 capture procedures, there exists an economic incentive to leave minor gas components in the captured stream geological storage, because doing so would reduce cost of process. However, co-injection reactive impurities (such as O , CO, H NOx, and SOx) may have detrimental effects on well injectivity, wellbore integrity, seal performance, gas–brine–rock interactions. this study we investigated, using a series autoclave experiments, potential impact impurity geochemical reactions. Three sandstones were tested: Miocene sandstone (Texas offshore, USA), lower Tuscaloosa (Cranfield field, Mississippi, USA) Cardium (Pembina Alberta, Canada). Samples subjected reaction with 1.88 M NaCl solution without addition small volume order determine . A total ten experiments conducted at 200 bar 70 °C or 100 °C. Overall, rock samples lacking reducing minerals, supercritical showed only limited compared reactions pure The presence did not accelerate dissolution carbonate feldspar nor it alter pathways. amount pyrite (≈0.7%) contained had important impact. As was oxidized, pH further lowered contains little pH-buffering minerals. Consequently, carbonates feldspars enhanced by more-acidic solution. Aqueous ferrous iron largely converted oxyhydroxides precipitated mineral surfaces. cations that largest increases aqueous concentration Mn, Sr, Ba) mostly mobilized from significantly low-pyrite sandstones. Releases trace metals, exception Zn Pb, fact, concentrations As, V, Mo, other oxyanions involving than reactions, these metals sorb newly oxyhydroxides.