露天煤矿道路双侧管路喷雾降尘数值模拟研究

卡车道路运输是露天煤矿最大粉尘源之一,粉尘污染对煤矿职业人群健康、卡车司机能见度均产生影响。湿式喷雾是从产尘根源上解决道路粉尘的有效方法,且喷雾参数直接决定防尘效果及其经济成本。以霍林河北露天煤矿卡车路面为研究背景,采用FLUENT19.2建立卡车道路喷雾降尘模型;分析喷嘴角度、孔径及喷洒量对粉尘浓度的影响机制。研究结果表明:卡车路面粉尘产生机制为碾压破碎、离心抛洒及诱导气;增加颗粒含水率可有效减少扬尘负荷,喷嘴最佳入射角度为30°时,雾距对路面覆盖度良好;喷嘴孔径为10 mm时,斯托克斯碰撞系数最大;喷水量为0.15 L/m^(2)及土壤含水率为4.0%时,路面粉尘控制效果最好。研究结论为有效控制露天煤矿卡车路面运输粉尘提供了理论依据。

Truck road transport is one of the largest sources of dust in open-pit coal mines.Dust pollution seriously damages the health of occupational groups in coal mines and affects the visibility of truck drivers.Wet spraying is an effective method to solve road dust pollution from the root of dust production,and the spraying process parameters directly determine the dust control effect and its economic cost.Using the truck road surface operation in the northern coal mine of Holin River as the research background,FLUENT19.2 software was used to establish a truck road spray dust reduction model;numerical simulations were conducted to analyze the impact mechanisms of nozzle incidence angle,nozzle aperture and spraying volume on road dust concentration.The results show that:truck road dust particles are mainly produced under the action of crushing,centrifugal throwing and induced airflow,concentrated on the side and rear of the wheels;the collision coupling between droplets and dust particles increases the water content of dust particles,which is conducive to reducing the dust generation load,and in order to make the spray fog scale have a good coverage of truck road dust,the best angle of incidence between the nozzle and the ground is determined as 30°.While the nozzle aperture of 10 mm,the Stokes collision coefficient is the highest.The best pavement dust control was achieved by maintaining a truck pavement water spray volume of 0.15 L/m^(2) and a pavement soil water content of 4.0%.The findings of the study provide a theoretical basis for achieving effective dust control on trucking surfaces in open pit coal mines.