Abstract: Aiming at the characteristics of upstream wet discharge tailings reservoir inflow tailings fine particle size,high concentration,not easy to separate,in order to realize safe stockpiling of tailings,ore drawing is carried out by grading and partitioning,after grading the coarse and fine tailings,the coarse and fine tailings should be drawn in front of the dam first,and the fine and fine tailings should be discharged in the upstream reservoir.Through the implementation of the cyclone classification and subarea drawing damming test in Nanjing Meishan Shanjing tailings pond,the reservoir tailings were classified under the pressure of 01 MPa by FX250 hydraulic cyclone,and the sediment mass concentration is diluted to less than 35% and discharged before the dam.The sampling test shows that +0.075 mm tailings account for about 90% in the range of 20 m in front of the dam,and the coarse particle content in the range of 40 m in front of the dam increases significantly.By constructing a pond ridge in the dam front area where the coarse tailings are deposited,the high safe zone can be formed when the coarse tailings are concentrated in the minimum dry beach length;the overflow is collected and piped to the upstream reservoir for discharge.The test results show that the upstream tailings classification and regional discharge process can solve the problems of insufficient flood control and low stability of high concentration tailings in front of the dam by hydraulic alluviation.The tailing stockpiling process has been successfully applied in Nanjing Meishan Shanjing tailing pond,which not only solves the potential safety hidden trouble existing in the early operation of tailing pond,but also saves the operation cost.

Key words: Tailings pond,Hydrocyclone,Graded stockpiling of tailings,Ore drawing damming test