On The Law Of Producing Dust And Control Dust Technology In Dry Drilling Coal Roadway

China's energy structure has been adjusted in 2016.Though the number of new energy has increased,the application and popularization of new energy will take a long time.And then the distribution of Chinese energy is characterized by more coal resources.Therefore,coal is still an important consumer energy in a long time.At the same time,with the continuous increasing depth of coal mining,a phenomenon of coal and gas outburst becomes increasingly prominent.Drilling technology in the coal seam is an effective measure to prevent these accidents.The preliminary of the gas drainage is about to build a large number of drilling in the coal seam or through the coal seam construction.And there are two types of drilling technologies based on exhaust dust medium.Among them,the dry drilling technology co mpared with the wet drilling technology has a high porosity,less water consumption and other advantages,so the former widely used in the application of mining coal.However,the process of the dry drilling will produce a large amount of harmful coal dust.Therefore,it is one of the technical problems to be solved urgently in the coal mining.This paper analyzes a large amount of dust produced in dry drilling technology that has a wide application in engineer.First of all,the mechanism of drilling rig,the influence factors of dust and the distribution and migration of dust in the drilling pipe are analyzed theoretically.And then the dusting characteristics of the dry drilling are put forward.Furthermore,the BP neural network model is established to predict the dust rate of dry bulb hole.Combined Huaibei Yuan Dian Coal,the well of Yuandian and ten coal mining,the BP neural network model is used and is far fitted for the reality.Last but not least,the new dry drilling device is designed based on a representative dry-type dust collection equipment.During the research on dust in drilling,the main contents are as follows:(1)The dust during dry drilling process is mainly from the bit on the coal body of the extrusion and friction.(2)Based on the system theory,the paper analyzes the influences factors of the coal dust during the dry drilling process,including the cognitive level of the construction personnel and the technical operation level,the hardness of the coal body and the comprehensive index,the moisture content and the solid-gas ratio that characterizes the operating parameters of the rig.(3)The distribution of dust through the Rosin-Rammler in the dry-type drilling process in coal roadway is 1.8599,that is,the dispersion is larger an d the proportion of the fine particle is larger.And then,the fine particle can not be easily capured.So t he dispersion of dust can be described as the overall generation of dust particle siz e distribution characteristics.The specific surface area and particle size of the dust not only measure the characteristics of fine dust,but also show the physical and chemical characteristics of dust.The specific surface area and particle size is inversely proportional to the larger surface area.The smaller the d ust particle,the greater the dust activity is.The density of the dust is the basis for selecting the type of dust removal equipment.(4)The dust rate prediction model of BP neural network in the dry drilling hole can illustrate a nonlinear relationship among the dust production and the hardness,moisture content,comprehensive comminution index,solid gas ration as well as.(5)The diffusion movement of the dry hole in the coal roadway is studied,and the density equation of diffusion and the model of the dust diffusion in coal roadway are established.The diffusion concentration equation of the dust is a joint distribution function of three independent and uniformly distributed random in three directions in coal roadway.(6)According to the law of the air curtain,the seal of mouth used it to stop the dust from flying in every direction.What 's more,anti-protruding board was designed in the drill pipe to keep coal body fitter.Finally,the broken dust was collected to the removable collective box and was wiped off based on the principle of water spray.Correspondingly a new type of dry drilling dust collector was designed.