DYNAMIC MODEL AND EXPERIMENT STUDY OF URANIUM MINE HEAP LEACHING PROCESS

The process model and chemical reaction constants of uranium mine sulfuric acid heap leaching are deduced by the relationship curve between the leaching rate and leaching time.The results show when the leaching rate less than 60%,it is linear with the leaching time,and the leaching process model is controlled by chemical reaction process.The chemical reaction leaching rate constant is 1.5 × 10-7 s-1,the liquid-solid phase chemical reaction coefficient is 3.6 × 10-8 m/s in this experimental data.It also shows that if oxidants were not added into the heap-leaching uranium ore,only 40% of the quadrivalent uranium could be oxidized into hexavalent uranium,so the oxidants must be added to improve the oxidizing ability for greater leaching rate of uranium.