关键词: 尾矿库, 严寒地区, 冻土

Abstract: Luming Mining Co., Ltd.；2.Sinosteel Maanshan General Institute of Mining Research Co., Ltd.） Abstract Improper ore drawing method of tailings reservoir in severe cold area will produce ore drawing frozen layer in sedimentary beach, which will affect the normal seepage and anti-sliding stability of tailings dam. Taking the ore drawing method for a tailings reservoir in a cold area as an example, the tem⁃ perature drop distance and freezing distance of the slurry flow are theoretically calculated, and the state of the drawing beach surface and the monitoring of the drawing parameters in winter are carried out. Accord⁃ ing to the exploration sampling and the temperature measurement in the hole, the occurrence of the frozen layer in the tailings accumulation and the temperature change law are determined. The results show that the freezing distance of pulp flow is far greater than its temperature drop distance, and the flowing pulp will not freeze before entering the ice cover. Concentrated ore drawing can quickly form a drawing flow channel, which flows along the flow channel to the ice sheet and enters the water. The flowing slurry plays a role in melting the surrounding frozen layer. The frozen soil layer below the dam surface has completely melted. The frozen soil layer in the reservoir area is distributed about 20 m below the sedimentary beach, and the maximum frozen soil thickness is 2~3 m. There is no frozen layer below the frozen layer, and the tempera⁃ ture inside the accumulation gradually increases to about 10 °C with the increase of depth. The results show that the ore drawing method of the tailings reservoir in winter is feasible. Before recovering the ore drawing in front of the dam at the end of the freezing period, the ice breaking operation is carried out on the surface frozen layer of the beach in front of the dam to destroy its integrity, accelerate its melting rate, and reduce the adverse effect of the frozen layer on the seepage and stability of the dam body.

Key words: tailings reservoir, severe cold region, frozen soil