Regularities for uranium leaching rate at different heights of column for leaching uranium from uranium ore

In order to understand the delay of uranium leaching at different heights in the heap leaching production, theoretical analysis and laboratory column leaching test were used to research the rule of uranium leaching at different heights of uranium leaching test column. The theoretical analysis divided the test column into several small enough and equal columns along the height, which ensures that the leaching of single ore particle corresponds to shrinking core model and diffusion control system, and the reaction of all uranium ore particles is uniform in a small column. Then, one small column was investigated as the typical case to build a mathematical model for the reaction in ideal state, based on the mass conservation principle of leaching agent and consideration the change of initial leaching agent concentration. Laboratory column leaching test of uranium ore was carried out using the uranium ore particles whose size (radius) is 2.5 mm, using a series columns of leaching test apparatus. And the results of the mathematical model of the uranium column leaching were calculated, and the results of model calculation and the results of uranium column leaching test were compared. The results show that the uranium leaching rate at different heights of the column are different, and there are the same trends for the model value and test data. So, the mathematical model is able to respond to the leaching delay at different heights of uranium ore heap, which provides an important reference to predict the leaching rate of uranium at different heights of heap leaching.