Simulation of Natural Convection in Acid Gas Disposal into Saline Aquifers

The storage and disposal of greenhouse gases in underground aquifer reservoirs is a suitable option for the reduction of these gases in the atmosphere. Understanding the concepts and mechanisms involved in the storage process such as natural convection and their impact on the amount of time required for storage is very important. Natural convection is an effective mechanism to increase the solubility of carbon dioxide in the storage process. In this study، the injection of carbon dioxide (a major component of greenhouse gases) into aquifer has been studied and numerically simulated. The effect of aquifer salinity on the onset of natural convection phenomena has been studied. To this end، six scenarios revolving around the change of aquifer salt and keeping the other variables involved constant in the process are studied. The results reveal a direct effect of salinity on the activation of natural convection. Increasing aquifer salinity delays the onset of natural convection. As a result، the cumulative amount of gas dissolved after the specified time will be less.