The Exploration Of "Double U" To "U+high-level Roadway" Arrangement In Yuwu Mining S1206 Working Face

With the development of mine ventilation system and domestic and foreign scholars' research in this field and the gradual perfection of relevant laws and regulations in China,the safety of coal mines in China is developing towards the direction of ensuring the safety of production and life and property.Gas as a major risk factor of coal mine safety production,seriously restricts the development of the coal industry,and in-depth implementation of gas control is the top priority of mine disaster prevention and control in China.Yuwumining S1206 working face does not comply with the provisions of the relevant rules of roadway layout in China in the "double U" ventilation system can not solve the problem of gas overrun and roadway layout under the condition of the working face of the switch to the "U+ high pumping tunnel ventilation drainage this idea of a feasibility study with the scientific significance of the working face and goaf gas control and high drainage roadway gas drainage effect.This paper studies the overlying strata fracture changes,analysis of fully mechanized caving gob "three horizontal" and "basic characteristics of vertical three zone",gives a method for rock in caving zone in different areas of the broken characteristics;at the same time according to the related calculation formula,calculate the height range three;according to the goaf theory of porous medium,analysis of properties of main parameters in goaf of the porous medium algorithm;analysis on gas migration and establish goaf gas flow mathematical model;the theory and analysis based on the FLUENT software is used to simulate different locations under high pumping Lane pumping tsetse goaf the gas concentration distribution,so as to determine the reasonable horizon of high pumping lane.According to the actual situation of the working face,the physical model of the goaf is set up,the relevant parameters and the boundary conditions are set,and the FLUENT numerical simulation software is used to simulate it.(1)to simulate the gas distribution in the working face and the goaf under the "double U" ventilation mode,and The level of the gas concentration distribution were obtained from the working face is in horizontal plane,the maximum height of caving zone in goaf level and fracture zone and the maximum height of goaf,found in the working face of the vertical direction through the observation,the upper part of the gas concentration is higher than that of the lower part of the gas concentration increased gradually along the working face;the inclined direction of gas concentration in one side,near the return air roadway,gas concentration increased rapidly,especially when the upper corner gas concentration increased significantly.Along the direction of goaf,the gas concentration gradually increases.In the deep goaf,the gas migration is smaller and smaller.The gas concentration is large and the gas concentration is very small.(2)Simulation of U+ high pumping tunnel ventilation under different horizontal position when the high drainage roadway drainage working face and goaf gas distribution in goaf bottom distance: the vertical distance is 40 m,the distance of return airway horizontal distance 20 m,30m,40 m,50,of working face and goaf the gas was simulated,and the working surface layer of goaf gas concentration distribution is similar to the observation that,however in different layers under high drainage roadway gas drainage concentration and pure quantity has certain difference,horizontal distance increases,high drainage roadway gas drainage gas concentration and purity was first a downward trend after rising,gas drainage concentration and pure volume maximum at 30 m,when the roadway continues to increase the horizontal distance from the air return roadway,high drainage roadway gas drainage concentration and pure volume has been reduced.From the above analysis we can see that when the roadway distance wind Lane horizontal distance of 30 m,the gas drainage concentration reached the maximum,and the gas concentration at different distances from the other angle is small,and in accordance with the provisions of the "coal mine safety Regulations" is not higher than 1% the requirements of.Therefore,it is reasonable to select 30 m as the horizontal distance of the distance return air lane.(3)When the horizontal distance of the high extraction lane is 30 m,the vertical distance from the bottom of the goaf is simulated with the vertical distance of 30 m,40m,50 m,and 60 m.The observation that with the increase of the vertical position of the roadway gas drainage concentration increases at first and then decreased in the range of 30 m to 40 m in the vertical height,high drainage roadway drainage gas concentration and gas drainage quantity is pure upward trend,while the work of these two layers on the surface of corner gas concentration little difference in the vertical angle,high 40 m,high pumping Lane pure gas drainage quantity and gas and the gas can effectively release the pumping and mining face goaf in tsetse,vertical height is 50 m and 60,with the increase of height,the pure gas drainage amount is more and more small,gas the concentration of air within the zone will be great,which may lead to the possibility of spontaneous combustion in goaf gas concentration change,increase the corner work surface is large,but still within the range of 1%.To sum up,when the high drainage roadway gob distance vertical height is 40 m,high drainage roadway drainage gas concentration,gas extraction purity was the highest,while working on the roadway surface under the action of corner gas concentration is 0.68%,in line with "upper coal mine safety regulations" provisions in the corner gas the concentration of less than 1% of the requirements.Therefore,combining these aspects,it is reasonable to use the height of the vertical height of the goaf to 40 m.(4)The comparison of different extraction methods is carried out to verify the rationality of "U+ high pumping alley" instead of "double U" ventilation mode.