尾矿库扬尘规律数值模拟研究

Numerical Simulation on Dust Raising Law of Tailings Pond

堆存在尾矿库中的尾矿在风蚀作用下会产生扬尘,对矿山安全与环保产生威胁。通过ANSYS Fluent数值模拟软件,模拟风流经过尾矿库的风速、风压状态,以及干滩面扬尘质量浓度和高度的变化,分析尾矿库的扬尘规律。模拟结果显示,风流正向经过坝顶形状凸变处时,风速大幅增加,风压在坝顶形状凸变处由正压变为负压。风速、风压的变化情况表明,该处更容易发生尾矿颗粒的松动从而产生扬尘。由干滩面扬尘质量浓度分布可知,尾矿库扬尘主要分布于干滩面上部10~30m处,随着风速的提高,扬尘质量浓度以及高度加大。综上分析,在坝体施工时,应增大坡比,临近坝坡顶面时,可铺筑碎石护坡,坝坡面植草;干滩面上应及时洒水或喷洒抑尘剂抑制尾矿库扬尘。

The tailings stored in the tailings pond will produce dust under the action of wind erosion,which poses a threat to mine safety and environmental protection.The ANSYS Fluent numerical simulation software was used to simulate the wind speed and pressure state of the wind flow through the tailings pond,as well as the change of the dust concentration and height of the dry beach surface,and to analyze the dust law of the tailings pond.The results show that when the wind flow passes through the convex shape of the dam crest,the wind speed increases greatly,and the wind pressure changes from positive pressure to negative pressure at the convex shape of the dam crest.The changes of wind speed and wind pressure mean that the loosening of tailings particles in this place is more likely to generate dust.From the distribution of the dust concentration on the dry beach surface,the dust from the tailings pond is mainly distributed in the upper 10~30mof the dry beach surface.With the increase of wind speed,the concentration and height of the dust increase.In summary,during the construction of the dam,the slope ratio should be increased.When it is close to the top of the dam slope,gravel can be paved to protect dam slope and grass planted on the dam slope.Water or dust suppressant should be sprayed on the dry beach in time to prevent dust from the tailings pond.