HIGH COLUMN LEACHING EXPERIMENT ON LOW-GRADE URANIUM ORE FROM A HARD ROCK DEPOSIT

In order to provide a reference for commercial experiment on stope leaching in a certain hard rock uranium deposit,conditional experiments were done in a column of 10m height.It is indicated that leaching of the uranium in ore is easy and distinct rules of uranium concentration, leaching yield and acid consumption in leaching solution for different column heights and particle sizes are that:①the uranium concentration at the bottom is higher than other parts and changes dramatically in initial leaching days but uranium concentration at same height drops steadily as time goes on;②the acid consumption in early days is more than that in medium and final stages;③the nearer to the top the ore is,the higher the leaching yield,but not the highest at the top;④the leaching yield increases as particle size of ore become fine,with an uranium extraction yield of 82.1% on residue for particle size of -50mm and 90.2% on residue for particle size of -15mm in it.It was suggested that intermittent sprinkling or dripping irrigation should be used to increase the leaching yield.