Dissolution mass transfer of trapped gases in porous media: A correlation of Sherwood, Reynolds, and Schmidt numbers

Abstract

The dissolution mass transfer of trapped phases in porous media is important in various fields, such as groundwater contamination, geological carbon sequestration, and geological energy storage. One of the difficulties in this study is the observation of the porous media interior during the dissolution mass transfer. Without the ability to monitor the process inside porous media, earlier studies were unable to measure the interfacial area of the trapped phase and thus were unable to calculate the mass transfer coefficient. In addition, complicating phenomena, such as two-stage dissolution and dissolution fingering, also affect the mass transfer process, in which it cannot be elucidated without observing to the porous media interior. In this present study, we investigated the dissolution mass transfer of various trapped phase in porous media at various fluid velocity by using micro-tomography. Therefore, the trapped phase interfacial area and mass transfer coefficient were successfully derived. In addition, the experimental setup was also designed to avoid the two-stage dissolution and dissolution fingering that could affect the mass transfer process significantly. As a result, we limit the observed phenomena to dissolution mass transfer processes alone. At the end, a mass transfer model based on Sherwood, Reynolds, and Schmidt numbers was developed. Because a mass transfer model that can be used for different trapped phases has never been developed, this developed model serves as an important reference for dissolution mass transfer model of trapped phases in porous media.