[en] Shallow hole shrinkage stope leaching has existence bulk, leaching corner, leaching effect poor and poor economic effect. By the free surface of shallow hole blasting action principle, a program for let out spraying shrinkage stope ore to the ground to heap leaching, is pointed out. The program can improve metal recovery and reduce production cost. So the implementation effect is good. (author)

[en] Mining low grade uranium deposit by stope leaching method is technically feasible and low cost. The practice has proved that the stacking of blasting fragmentation is one of the main factors that directly affect leaching effect. Based on the specific environment and safety, clattering blasting heap size, improving the quality of the heap of stope leaching process become extremely critical issue.Based on the study and practice of blasting railway construction and open-pit mining, combined with a uranium mine in Gannan resource conditions and the actual situation of production, application and exploration test of deep hole blasting in of heap construction technology, the results show that the bulk yield can be greatly reduced, quality and heap stope leaching effect can be improved. (authors)

[en] In mining low grade uranium deposit, in situ blasting and heap leaching is technically feasible with low cost. By many years practice demonstration, lumpiness of blasting and heap construction is one of main factors which influence of uranium leaching effect. How to under the specific environment and ensure safety condition, controlling lump size of in situ blasting which are used in heap leaching and improving the quality of the heap become extremely critical issue in situ blasting and heap leaching process. Based on the study and practice of blasting in railway construction and open-pit mining, in combination with the resource conditions and the actual situation of production in one Gannan uranium mine, application and exploration of deep hole blasting test and stratification of heap construction technology in stope was carried, the test results show that the bulk yield rate is greatly reduced, quality and heap leaching effect in stope are greatly improved too. (authors)

[en] A shallow hole shrinkage mining stope leaching method was used to recover uranium in a uranium mine. The problems such as large blasting fragmentation and uneven distribution of drill lixiviant resulted in low leaching rate, long leaching cycle and low production efficiency during production. Aimed to problems and combined with the actual situation of the uranium mine, the shallow hole shrinkage mining method was improved, that is, according the results of geophysical logging, high grade ores and low grade ores were blasted and mined respectively, and the high grade ores were sent to the surface and treated by heap leaching process, and low grade ores were leached in stope. This improved method was called shrinkage mining method with respective blasting and mining. Compared with shallow hole shrinkage mining stope leaching method, the recovery rate of the improved method was increased by 17.2%, thereby maximizing the recovery of uranium resources. (authors)