Pore-scale investigation on porous media morphology evolution considering dissolution and precipitation

Abstract

Mineral dissolution and precipitation are commonly encountered in geologic CO₂ injection. In this study, a novel method DLA-QSGS coupling diffusion limited aggregation (DLA) and quartet structure generation set (QSGS) is proposed to generate random distribution of mineral components and fluid. As an example of application, the reactive transport process is then numerically studied with various pore morphology using the lattice Boltzmann method at pore-scale. An insoluble mineral component and soluble mineral components that involve simple and complex reactions for dissolution and precipitation are considered. The impact of mirror morphology, channel width and sub-channels on solid volume evolution and hydrogen ion concentration are investigated. The temperature field is affected by the channel width and sub-channel number. The results suggest that the technique increasing channel numbers is more effective than that increasing channel width during CO₂ fracturing.