Research Of Air-water Jet Atomization Prevention And Control Technology For Fully Mechanized Excavation And Cutting Of Dust And Gas

With the further improvement of coal mine mechanization level,the intensity of underground coal operations is also increasing.In the process of mechanized mining,comprehensive cutting is often accompanied by the problems of excessive dust concentration,corner gas over limit and impeller friction spark.It is very important to solve these problems so as to ensure the safety of comprehensive cutting.Based on the problems of comprehensive tunneling cutting,In this paper,these problems are studied on the basis of previous studies and combined with the air-water jet technology.Because the air-water jet spray device does not have internal mechanical device,the friction spark problem of mechanical impeller is fundamentally eliminated,and the device does not need to provide kinetic energy with electricity,so there is no electric spark problem..Firstly,theoretical research and analysis are carried out in this study.The main content of this study is to study the spray theory and ventilation mechanism of air-water jet.Combined with the dust and corner gas generation mechanism and motion characteristics of comprehensive cutting,the action mechanism of air-water jet in dust settling and gas dispersing is determined.Secondly,using numerical simulation software fluent,the first component transport equation is used to comprehensive tunneling when cutting the romantic,corner gas distribution of flow field simulation,and then using the discrete phase model of comprehensive tunneling cutting dust transport situation of the study,the numerical simulation results show that air water jet increases the comprehensive tunneling cutting when the wind speed,improved the wind flow,It can obviously improve the corner vortex and reduce the concentration of gas in the corner.In addition,the dust migration is improved,and the dust mostly settles on the floor of roadway.After that,laboratory experiments with different nozzle structures and air-water supply ratios were carried out,through comparing the different experimental parameters,found 5 best spray nozzle structure parameters,different parameters of air-water jet spray with water pressure,pressure change trend,the airwater jet spray parameters than the best air-water to water pressure 0.25 MPa,pressure is 0.4 MPa,On this basis,an experimental platform for dust removal and gas dispersive was built,and the dust removal effect and gas dispersive effect were verified.The results showed that the maximum dust removal efficiency could reach 97%.Finally,the industrial test was carried out in Yuandian Mine of Huaibei Mining Group to verify the industrial application of the air-water jet.According to the analysis of the field measurement data,the air-water jet spray has a very good effect on the dust removal and corner disperse of comprehensive excavating.Through the above analysis and research,it is verified that the air-water jet has an obvious effect on the dust and gas problems of the comprehensive excavation and cutting.It has good practicability for the comprehensive excavation and cutting operation and has a high use value.