Flow through Experiment on CO2-brine-rock Interaction in a Sandstone from the Altmark Gas Reservoir

摘要: We performed flow through experiments to study the water-rock interactions caused by CO2 injection in sandstones obtained from Altmark natural gas reservoir under conditions of 125°C and 50 bar partial pressure. CO2-saturated brine (41.62 g/ L NaCl 31.98 g/L CaCl2•2H2O), mimicking chemical composition formation water, was used as an solution. The major components sandstone were quartz (clasts cement), feldspars, clay minerals (illite chlorite), anhydrite, latter present mostly cement. Trace amounts carbonate barite cements also present. Fluid analysis suggested predominant dissolution anhydrite causing increased concentrations sulfate at early time periods. Dissolution feldspar, minor chlorite) evident during flow-through experiment. Geochemical modeling does not predict secondary mineral precipitation these conditions. experimental data could be for numerical simulations predicting storage reservoirs.