露天煤矿半封闭煤棚通风降尘数值模拟研究

Numerical simulation on ventilation and dust reduction of semi-closed coal shed

宝日希勒露天煤矿筛分栈桥煤棚是临时储煤仓及装车点,随着作业环境的改变产生不同浓度粉尘。针对高浓度粉尘对工人身体健康和生产安全造成的影响,根据气固两相流理论,采用FLUENT软件进行数值模拟分析半封闭空间煤棚内粉尘运移扩散规律。将数值模拟与现场试验结合,研究煤棚风机两侧抽风和一侧压风一侧抽风煤棚内的粉尘浓度及风速变化。结果显示,煤棚内粉尘中主要为难沉降的PM_(2.5),占全尘的72.9%;煤棚内粉尘浓度与风速呈正相关;通过一侧压风,另一侧抽风的通风方式相较两侧抽风的方式除尘效率提高,可以实现粉尘的从下到上,从压风侧到抽风侧的定向运移。

The screening corridor coal shed of Baorixile Open-pit Mine,is a temporary coal storage bin and loading point,where different concentrations of dust is generated as the operating environment changes.The high concentration of dust affects the health of workers and the working environment.Based on the theory of gas-solid two-phase flow,FLUENT software is used to analyze the law of dust migration and diffusion.Combining numerical simulation with field test,the changes of dust concentration and wind speed in the coal shed is studied under two-side negative ventilation and series ventilation.The results show that the dust concentration in the coal shed is positively correlated with the wind speed,and PM_(2.5)accounts for 72.9%of the total dust.The control of the dust in the coal shed gives priority to the treatment of PM_(2.5).Under the action of air pressure on one side and extraction on the other side in the series ventilation,the dust moves from bottom to top,from the pressure side to the extraction side can be realized,thus to improve dustremoval efficiency.