Changes in Microfine Particle Migration of Ionic Rare Earth Ores during Leaching

Abstract

The hydration mechanism between the leaching agent and ore surface during the leaching process of ionic rare earth ore is complicated, and the inter-particle bridge cementation is prone to fracture due to the existence of multiple forces and dispersion during ion adsorption and exchange, resulting in migration and rearrangement of microfine particles, and precipitation at the pore throat, producing blockage phenomenon and affecting the leaching efficiency of ionic rare earths. In order to reveal the migration law of microfine particles during in situ leaching of ionic rare earth ores and to find suitable regulation methods, this paper investigates the effects of leaching agent mass concentration, viscosity, flow rate, hydraulic gradient, ore body height, and ore body water content on the migration of microfine particles. We compared ionic rare earth ores as raw ores and rare earth ores with particle sizes ranging from 0.075 to 0.09 mm using the laboratory column leaching method. The results showed that the migration of microfine particles during ionic rare earth ore leaching was an important factor affecting leaching efficiency. Under the action of external forces, the microfine particles tended to migrate with the leaching agent during the leaching process.