Filling. Mine High Concentrations Of Coarse Aggregate Theoretical Research And Applications

In the process of exploitation mineral resources exploitation, the waste rock, tailings and smelter slags are the main source of industrial solid wastes in China' traditional mining pattern, with a discharge ratio as high as 85%. A large number of the solid waste piled up on the ground in mines can cause serious pollutions, and may induce mudflows and tailings dam-break accidents. As the supporting technology of green mining, the solid waste backfill is the most effective way to solve the discharge of mine waste. However, utile now, the coarse aggregate pipeline-conveying filling technology is rarely used in mines and there is little research reported on coarse aggregate grading theory, slurry density and backfill strength design on the condition of pipeline-conveying. In fact, there is a best mixture ratio among aggregates, cement and water about the materials of filling slurry, to achieve the minimum costs, highest strength and optimum density to delivery. Furthermore, the solid waste backfill technology must meet the requirements of high-density, high-flowing, self-compaction and low costs. Based on the points above, this dissertation have finished deep research on the filling material grading theory, slurry density and backfill strength model etc., and have successfully developed a new technology of the waste rock-total tailings high density filling industrial method.At present, coarse aggregate pipeline-conveying filling process is rarely used and there is little research on coarse aggregate grading theory, slurry density and backfill strength design amid pipeline-conveying. In fact, there is a best mixture ratio among aggregates, cement and water about the materials of filling slurry, in order to achieve minimum costs, highest strength and optimum density to delivery. Based on the points above, this dissertation have finished deep research on the filling material grading theory, slurry density and backfill strength model etc. and refer to an successful experiment about the waste rock-total tailings high density filling industrial method.Based on the stacking interstitial effect of aggregates, the author analyzed and established several models of packing compactness for two kinds of filling aggregates, three kinds of aggregateand and several kinds of filling aggregates, and obtains the best mix proportion model with the solution method for it. This model is further proofed by experimental results. This model can effectively solve the problem of grading adaptability between waste rock and total tailings in mines. In addition, based on a substantial number of experiment results, a new model of strength prediction is proposed. The advantage of this model is involving the influence of many factors, such as aggregate, cement and water on strength, which is helpful for regression analysis. The technique of downward drift slicing and high concentration transmission and filling for waste rock and tailing making the filling processing with the advantages of high concentration, high flowing, self-compacting and low cost. This technique characterizes high concentration and paste filling, which is a low cost filling technique for waste rocks.According to the source and the current condition of filling aggregate in Jinchuan mines, my research found that Gobi pebble has better crushability. The results show that the crushing formation could turn into "breaking" from "grinding" through the size of milling increases to-8mm, which extends the use of filling with coarse Gobi aggregate and waste rocks and also reduce the cost substantially.Waste rock and tailing are the major industrial wastes of mine enterprise without shortage problem. How to use the waste rock and tailings to backfill is a frontier project. In this paper, graduation model for coarse aggregate and density/strength model are established, which solves the essential application problem of coarse aggregate with high density pipe-conveying filling technology. This new filling technique makes it is possible to use all waste rocks and tailing as a resource for filling, which achieves the goal of green mine with zero discharge. In addition, the plant practice has proved it can greatly reduce the filling cost by using coarse rock aggregate. So, most of mines can afford it. Therefore, the technique and results obtained in this research could be applied to much more areas.