A method for backfilling mine tailings surface subsidence pits by caving method

Abstract

The invention provides a method for backfilling a subsidence pit on the surface of the tailings in a caving method mine. The method of the present invention comprises: (1) preparing the tailings backfill of the subsidence pit; mixing and stirring the cementitious material and the tailings at a ratio of 1:6 to 1:8, so that the concentration of the backfill slurry reaches more than 65%; (2 (3) Determination of the average expansion radius of the solidified tailings slurry single-point stacking flow: the average expansion radius of the solidified tailings slurry single-point stacking flow is determined to be 20m; (4) Backfill solidification: stacked on site Set up a tailings solidification backfill unit every 20m along the boundary arc length of the stacking position in the sub-safe area, and discharge the prepared backfill directly into the designated backfill unit; the thickness of a single stack is 4.59‑4.59m~9.78 m, the curing time is 14 days, and cyclic backfilling is carried out. The invention can solve the potential safety hazard of the tailing pond, save a large amount of land, solve the safety problem of the surface subsidence area at the same time, and greatly reduce the engineering quantity and cost of geological disaster control at the end of the mine.

Description

Technical field: [0001] The invention relates to a method for backfilling surface subsidence pits using tailings in caving mines, and belongs to the technical field of mine tailings utilization. Background technique: [0002] Tailings are "waste" discharged by mining enterprises under certain technical and economic conditions. By the end of 2015, the tailings stockpile in my country had reached 14.6 billion tons, and the number of tailings ponds nationwide had reached more than 12,600. The stockpiles cover an area of ​​18,700 to 24,700 km2. At present, most mining enterprises adopt the method of wet direct discharge to deal with tailings. The tailings naturally precipitate, and the dehydration efficiency is very low. A large amount of clarified water and floods are often stored in the tailings reservoir area, resulting in the formation of hanging lakes above the tailings. A source of danger and environmental risk with high potential energy and high hazard has been formed. T...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to provide a method for backfilling mine tailings surface subsidence pits in caving mines in view of the above existing problems, which can not only solve the potential safety hazards of tailings ponds, save a lot of land, but also solve the safety problems of surface subsidence areas, Greatly reduced the amount and cost of geological disaster management at the end of the mine

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