An engineering solution for CO2 injection in saline aquifers

The advantages of this method are that there is little overall pressure increase, because CO2 is mixed with brine extracted from the formation, and also the extracted brine is already at high pressure when it is mixed with the CO2, greatly increasing the solubility of CO2 and reducing the volume of brine required. Energy is not expended lifting the brine to surface nor is there any concern about handling large volumes of acidic brine in the surface equipment. In this study, in addition to the concept of the down-hole mixing (DHM) method which is presented, the application of the DHM method in a hypothetical storage site (Lincolnshire-Smith et al., 2012) is also examined. The calculations are performed to identify the optimum rates of water extraction and injection of dissolved CO2 in brine.