Evaluation of the impact of CO2, co-contaminant gas, aqueous fluid and reservoir rock interactions on the geologic sequestration of CO2

We present here the results of reactive transport simulations made to investigate the long-term impact of dissolved CO2, H2S and SO2 on carbon sequestration in the Frio Fm., TX. The results suggest that addition of relatively large amounts of H2S to a CO2 injection should not adversely impact injectivity or sequestration compared to the injection of CO2 alone. The co-injection of SO2, however, could produce significantly different results, if conditions are such that SO2 can oxidize to sulfate. In the long-term the simulations suggest that carbonate mineral formation can sequester a significant fraction of the injected carbon through the formation of calcite, magnesite and dawsonite.