Optimizing CO2 storage in a deep saline aquifer with the capacitance-resistance model

CO2 storage in deep brine-tilled structures accompanied by brine extraction has several advantages over conventional large-scale storage schemes. Using conventional reservoir simulators to optimize CO2 injection/brine extraction requires a model of the petrophysical properties of the storage formation. When those properties are poorly characterized, a useful alternative tool is the Capacitance-Resistance Model (CRM), which only requires the wells' injection/extraction histories as input. One important characteristic of CRM is that it identifies the connectivities between injectors and extractors. We show the effectiveness of the method on a homogeneous aquifer \kith variable injection rates. We further describe a workflow that optimizes subsequent CO2 storage in the aquifer using the CRM model parameters obtained from the injection/extraction history. The approach is illustrated on a heterogeneous storage aquifer and the results show a significant improvement in the amount of CO2 stored in the aquifer. (C) 2013 The Authors. Published by Elsevier Ltd.