Stimulation of in situ uranium leaching from low permeable ore in treatment by different physical methods; [ИССЛЕДОВАНИЯ ИНТЕНСИФИКАЦИИ ПРОЦЕССА СКВАЖИННОГО ПОДЗЕМНОГО ВЫЩЕЛАЧИВАНИЯ УРАНА ИЗ СЛАБОПРОНИЦАЕМЫХ РУД ПРИ ВОЗДЕЙСТВИИ НА НИХ РАЗЛИЧНЫМИ ФИЗИЧЕСКИМИ МЕТОДАМИ]

The resources of in situ leach uranium mining mostly represent hydrogenous low-grade ore deposits in impermeable sandy and clayey sediments in the crustal depression zones. It is possible to involve low permeable ore in the mining and processing cycle chiefly by means of the in situ leaching stimulation using various physical and chemical methods aimed to enhance permeability of ore bodies for leaching solutions. This article describes the lab-scale experiments and full scale studies on stimulation of in situ leaching in low permeable uranium ore deposits of NavoiUran. The studies aim to increase efficiency of in situ uranium leaching using such physical methods as ore treatment by alternating current, magnetic processing of acid solutions and application of ultrasonic vibrations. The lab-scale experiments show that alternating current stimulation raises both the permeation factor and the metal recovery rate. For example, the passage of alternating current at a density of 0.1–0.01 mA/cm2 increases the permeability factor by 1.2 times. The full scale studies prove this result and exhibit the increased output of wet holes by 5 times on average. The capability testing of magnetic processing of acid solutions in the in situ leach technology included estimation of leaching velocity of magnetic solutions, observation of change in permeability of rocks with the magnetic solutions and determination of precipitation rates of mechanical impurities and gypsum in the magnetic solutions. The lab-scale experiments find that magnetization of acid solutions promotes precipitation of gypsum and mechanical impurities, which may be practically useful in purification of process solutions. The lab-scale investigation of ultrasonic vibration effect on leaching performance shows that both the leaching velocity and the metal concentration in solutions increase noteworthily. © 2023 Publishing house Mining book. All rights reserved.