Abstract:In process of uranium extraction by acid leaching, gypsum will be formed during dissolution, precipitation and redissolution of uranium, which will lead to change of porosity and uranium leaching migration. Taking an actual uranium leaching process as an example, a comparative analysis of different models under porosity change by model generalization was constructed to explore these changes. The results show that: 1) After simulation process (600 days), porosity of the whole model changes to different degrees. Within cross sections of pore 2 and pore 5, porosity at 0 m rises the most with an increase of 3.66%, and that at 8 m drops the most with a drop of 1.66%. 2) Leaching rate of uranium ore positively correlates with porosity of the site. When t=8 d, the porosity of production model at 0 m reaches the maximum, and the difference between uranium residue of ideal model and production model also reaches the maximum. Uranium residue of ideal model and production model is 54.84% and 54.74% respectively. At t>8 d, porosity and uranium leaching rate of production model at 0 m begin to drop. At t=18 d, uranium surplus of ideal model and production model is equal. 3) Ore bed with reduced porosity directly affects migration of leaching solution in it, reducing effect of uranium leaching migration. When t=600 d, porosity of production model at 8 m reaches the minimum value, and influence of leaching solution migration obstacle reaches the maximum. Difference of pitchblende residue between ideal model and production model at 10 m also reaches the maximum value, the ideal model is 9.65%, and the production model is 13.34%.