Influence Law Of Mining Sequence Of Working Face Of Yili No.4 Mine On Groundwater Flow Field

Yili No.4 Mine is located in the oasis area of the Yili River Valley.The coordination between coal mining and fragile grassland ecological protection must be based on water resources carrying capacity.Based on the study of shallow buried depth,weak cementation and thin bedrock in the 41-1 fully mechanized mining face of No.21-1 coal seam in Yili No.4 Mine,Xinjiang,the numerical simulation method is used to analyze the different order of the working face to the aquifer.The influence of the permeability coefficient and water level depth,lateral influence radius and seepage velocity on the water surface is explored.The following results are obtained:(1)The variation curve of overburden permeability after coal seam mining is symmetrically distributed,and the peak appears directly above the goaf,and shows a trend of decreasing from the upper side of the working face.After reaching the minimum on both sides of the working face,the distance is The working surface distance increases and the permeability increases gradually.(2)Under the same number of mining times,the larger the area of the island working face formed by the jump mining,the greater the permeability of the overlying rock stratum;the permeability of the overlying strata with the increase of the number of mining times in different mining times Will gradually increase.(3)In the case of the same number of mining times,as the area of the isolated working face formed by the jumping mining increases,the water level deepening,the seepage velocity and the lateral influence radius of the regional groundwater will increase accordingly;Under the circumstances,as the number of mining faces increases,the groundwater level will decrease,the seepage velocity and the lateral influence radius will increase accordingly.(4)Based on the consideration of groundwater resources protection,the post-harvest groundwater level deepening,seepage velocity and lateral influence radius of the designed 24 sets of mining sequence schemes are compared,and the most reasonable coal seam of No.21-1 in Yili No.4 Mine is obtained.The mining order of the working face is Scheme 7(21103,21102,22105,21107).