Research On The Dust Distribution Law Of Multiple Dust Sources In Fully Mechanized Caving Face

With the increasing mining scale of mines and the widespread use of high-power and highperformance coal mining equipment,the mining intensity of fully mechanized top coal caving face has also increased,making the dust concentration in the working space of the face higher and higher.The environment is further deteriorating,and due to the large number of dust sources at the fully mechanized top coal caving face,the dust movement laws are becoming more and more complicated.Therefore,increasing the research on the movement laws of flour dust in fully mechanized top-coal caving work will be conducive to the optimization of on-site dust reduction measures and the improvement of the environmental quality of the working face,and is of great significance to the improvement of the mining efficiency of fully mechanized topcoal caving face.This article takes the 8105 fully mechanized caving face of Majiliang Coal Mine as the research object,and combined with the method of numerical simulation,first of all,the theoretical method is used to study the basic properties of the working flour dust and its stress and movement status.The experiment analyzed the concentration,dispersion and wettability of working flour dust.The FLUENT numerical simulation software was used to study the wind flow law on the working face.The main dust production processes of fully mechanized caving face are shearer cutting coal,hydraulic support moving frame and top coal caving operation.The dust distribution rules of these three dust source points were studied respectively,and the fully mechanized caving face The dust movement law and dust concentration distribution law under the action of various dust sources.According to the obtained research results,put forward targeted dust control measures for the prevention and control of flour dust in fully mechanized caving work.The main research results achieved in this paper are as follows:(1)Obtained the distribution characteristics of the wind flow in the fully mechanized caving face,that is,the wind flow in the air inlet is evenly distributed,and the wind speed is maintained at about 2.1 m / s.When the wind flow passes through the transfer point,the first obvious disturbance of the flow field occurs Flow,the wind flow quickly diverts to the sidewalk space,causing the wind speed in the sidewalk space to increase rapidly,the maximum value is 3.3 m / s;when the wind flow passes through the shearer,the flow field has a second disturbance,and the space near the shearer The wind current field is extremely complex.(2)The dust generated by the shearer cutting coal mainly spreads along the shearer tunnel space.The closer to the front coal wall,the greater the dust concentration.The airflow at the working face plays a decisive role in the diffusion of the dust generated by the coal cutting operation.(3)When the hydraulic support moving frame produces dust alone,the movement of dust is mainly affected by gravity.As the height continues to decrease,the influence of dust on the sidewalk space increases and the harm to workers on the working surface increases.(4)After the dust is generated by the top coal mining operation,the dust quickly moves downwind to the sidewalk space.Since the dust source point of the top coal is closer to the floor of the working face,most of the dust settles on the floor of the working face.(5)Under the joint action of multiple dust source points,the dust concentration distribution of fully mechanized caving work is extremely complicated.The dust concentration will rise sharply every time the wind flow passes through a dust source point.(6)On the basis of theoretical analysis laboratory tests and numerical simulation,the existing dust removal measures of the working face are optimized,and the dust control concept of "control" of the dusty air flow in the fully mechanized caving face is put forward,that is: on the working face Use dust-proof measures such as full-section spraying in areas with more sidewalks or other workers to change the movement of dusty winds and reduce the damage of dust to workers and mechanical equipment on the working surface.