Research On Dust Migration Law In Fully-mechanized Heading Face And Multi-Stage Dust Removal Technology

With the expansion of roadway section and the implementation of super-long distance rapid driving technology,make the dust production volume increased sharply,due to the characteristics of its single-head long distance ventilation,As a result a large amount of dust accumulates from head to face and diffuses to the whole roadway.The adverse working conditions greatly increase the safety and health of underground workers.Therefore,it is of great significance to study the application technology of high efficiency dust removal in fully mechanized heading face.In this thesis,based on the theoretical analysis method of flow field,the distribution law of wind flow field and dust field in 4210 fully mechanized excavation face of Jianxin Coal Mine is simulated and analyzed by Fluent software.It is concluded that the low wind speed eddy zone will form at the driver's position of the roadheader,which will lead to dust accumulation and the distribution of wind flow and dust concentration along the backflow zone and jet zone.The feasibility of the simulation method is verified by comparing the simulation results with the measured data.Secondly,the method mentioned above is used to simulate the combined dust removal and ventilation mode of 2410 fully mechanized heading face in Yuhua Mine,and the efficiency and the optimum range of technological parameters of the dust removal method are obtained by combining with the calculation of measured data.According to the above analysis results,the paper designs and simulates the ventilation mode of dust collection and ventilation in 4210 fully mechanized heading face of Jianxin Coal Mine,and obtains the dust removal efficiency,and studies the distribution law of dust particle size under this dust removal ventilation mode.It is concluded that the proportion of small particle dust(particle size less than 40 ? m),which is 50 m away from the head of head,is more than 60%,and it is necessary to further control it.Finally,aiming at the problem of small particle dust remaining and the dust rising at the second running load point in 4210 fully mechanized heading face of Jianxin Mine,it is put forward that a wet full-section dust capture curtain control system should be set up at the position of 40 m from the head of the roadway(warning line).The hardware and software design and the system experimental platform are designed according to the functional requirements of the system,and the function test results can achieve the desired results.The conclusion of the study deepens the understanding of wind flow field,dust migration and distribution of concentration along the road of fully mechanized working face,and comprehensively applies multi-stage dust removal means,such as combined pressure dust removal ventilation spray outside of fully mechanized excavator and wet full-section dust capture curtain dust spray system,etc.It can significantly improve the dust removal effect of 4210 fully mechanized working face and provide guarantee for the safety and health of underground operators.