Technological Parameters Research Of Non-pillar Sublevel Caving In Shirengou Iron Mine

Non-pillar sublevel caving structure parameter reasonable or not is directly related to the size of mining quasi engineering quantity, excellent and inferior index of ore loss and dilution, mining costs, the degree of intensive mining operations and mining efficiency and so on. While the essence of mining structure parameter optimization is to study"goodness of fit problem of the shape of blasting accumulation body and drawing-off volume"and"optimization problem of drawing-off volume spatial arrangement".According to theory of drawing-off volume, the study put up with the criterion to determine the optimal structure parameter with the principle of drawing-off volume and ore heap tallying identical; the study indeduced the counting formula of optimal drift interval and drawing pace on the condition of ore heap height equal to double sublevel height's undiluted ore drawing-off volume. In addition, taking Shirengou iron mine as research object, we individually established 6 variety structure technological parameter of sublevel height 10, 12, 15m, drift interval 10～20m and the PFC2D two-dimensional numerical simulation model. The simulation results showed that ore recovery and the rate of rock drop-in not only had simultaneous increasing law, but sublevel number also had an impact on the simulation index. The first sublevel recovery and the rate of undiluted ore recovery were very low, the rate of rock drop-in was high; The second sublevel the indexes significantly improved; while the third sublevel the rate of undiluted ore recovery and total recovery increased, the rate of rock drop-in decreased and recovery index were stable. With sublevel number increasing, simulation indexes were better. That was the rate of undiluted ore recovery and total recovery increased and the rate of rock drop-in decreased.Finally, the paper analyzed grey decision by grey decision theory model and obtained that the optimal parameter scheme of Shirengou iron mine non-pillar sublevel caving was schemeⅣ, that was sublevel height×drift interval×ore breaking pace=10m×16m×4～5m of the structure parameter.