Research And Application Of High Water Material Hole Sealing Technology In Xinjing Mine 3216 Working Face

With the increase of mining depth,gas content and gas pressure in the coal seam increase dramatically,and the working condition is getting worsen,causing the frequent gas accidents which severely restrict the safe production.This paper takes xinjing mine 3216 working face as the engineering background.The performance of high water material on sealing holes was examined.The size and material of pouch was improved,and the performance of modified hole packer is confirmed by numerical simulation and field test.The research outcomes are as follow:(1)The basic parameters including gas content,initial speed of diffusion,firmness coefficient and porosity were gotten by the method of combining field test with laboratory test.(2)The single variable method was used to design the experiment program.The effect of water consumption,the matching of two materials on solidification time,uniaxial compressive strength,expansion rate and permeability of the high water material was discussed.The optimum matching meeting gas drainage borehole requirement was obtained.(3)The design of gas sealing machine was optimized,considering the optimum maching of high water material gotten from the experiment.The effect of different materials and length of pouches on efficience of sealing boreholes was examined,so the optimum length and type of pouches were found out.(4)The influence of different diameters of boreholes,different distances between boreholes and different depth of boreholes on gas gas drainage efficiency was studied by using COMSOL numerical simulation software.The resuls reveal the change law of gas concentration during gas drainage,supplying important theoretical basis to the design of gas drainage in working face.(5)On the basis of modified design of high water sealing hole machine and the numerical simulation of borehole gas drainage,the gas drainage efficiency in working face was analysed.The feasibility of high water material sealing hole machine was is proved through comparing the quantity of gas drainage before and after improvement.The paper includes 51 pictures,16 tables,98 references.