Simulation of multiple parameter effects on efficiency of uranium ore acid leaching

Abstract

This study investigates factors influencing the leaching process in uranium mining, using a uranium mine in Inner Mongolia, China, as a representative case. We used PHREEQC geochemical and COMSOL Multiphysics® software, as well as the coupling interface COMSOL PHREEQC (iCP), to simulate acid leaching of underground core mineral samples. The study systematically analyzes the effects of sulfuric acid concentration, permeability coefficient, and injection/leaching pressure differential on uranium leaching efficiency. It also reveals spatial and temporal variations of minerals throughout the leaching process. The findings include a positive correlation between sulfuric acid concentration and leaching rate. Increased permeability significantly enhanced the leaching effect, while the injection/leaching pressure differential had an optimal range. Additionally, mineral evolution characteristics suggested that acidophilic minerals dissolve rapidly in initial stages, whereas later stages may involve minerals such as kaolinite and quartz influencing pore structure. These findings provide a foundation for optimizing process parameters in uranium mining and offer a quantitative reference for micro-scale mineral changes, ultimately for efficient and sustainable uranium extraction.