Research On Application Of High Pressure Spray Dust Removal Technology In Fully Mechanized Mining Face

With the gradual improvement of underground coal mine mechanization and the continuous increase of mining intensity,the dust problem caused by this has become more and more serious.As the place with the largest dust production,the comprehensive mining face is due to the complexity and particularity of its environment.Dust control is also relatively difficult.Excessive dust concentration will not only affect the normal production of the mine,but also seriously threaten the lives of employees.Therefore,the problem of dust prevention in fully mechanized mining face must be paid attention to.First of all,this thesis analyzes the mechanism of high-pressure spray atomization,the mechanism of dust removal,and the influence factors of spray dust removal.The high-pressure spray experimental platform is built in the fluid laboratory of Hebei University of Engineering.Through the selection,installation and commissioning of spray system equipment,different researches The atomization angle and effective range of the direct-injection nozzle with the outlet diameter of 1 mm and the centrifugal nozzle under the spray pressure are changed,and the atomization characteristics of the centrifugal nozzle with different outlet diameters under the same spray pressure are explored.The results show that when the spray pressure of the same nozzle increases,the effective range gradually increases,and the atomization angle gradually decreases;when the spray pressure is 8 MPa,as the outlet diameter of the centrifugal nozzle increases,the atomization angle and effective range are both It increases with it,but the effective range does not change significantly.Secondly,establish a longitudinal swirl nozzle simulation model,use FLUENT software to carry out numerical simulation research on the internal flow field of the nozzle,and analyze the influence of the swirl core spiral angle and the length ratio of the contraction section to the swirl section on the atomization effect.The swirl cores are different in spiral.The angle has a great influence on the outlet speed.Appropriately increasing the spiral angle within a certain range is beneficial to increase the nozzle outlet speed.The length ratio of the nozzle contraction section and the swirl section has a certain influence on the spray effect.If the ratio is too large or too small,it is not conducive to the mist of the fluid.The ratio of the two is about 1,that is,the spray effect is best when the length of the contraction section and the swirl section are similar.Finally,according to national standards and industry standards,the dust generation characteristics,dust characteristics,and dust migration rules of 5102 fully mechanized mining face in the first mining area of Pulongwan Mine of Shanxi Coal Group are analyzed,and the problems of spray dust removal on this face are explored,and the design Combined spray system,good dust removal effect for field application,and optimized internal and external spray of the shearer.The improved internal spray nozzle arrangement achieves full coverage of a single pick,and each rocker arm has three external sprays.The nozzles respectively point to the center of the drum and the picks on both sides to spray,which greatly increases the contact area between the fog field and the dust.