Study on the development and utilization of water-preserved coal mining in Dajing area of eastern Junggar coalfield

Based on the analysis of the geological data of coal deposition in eastern Junggar coalfield, five aquifers and water-resistant strata of overlying rocks are recognized.The major coal seam B₁ is involved in formation of IV aquifer.The development heights of water-conducting fractured zones induced by large mining height and caving mining of super-thick seam in Dajing mining area are estimated using the conventional and empirical methods.The calculated height of water-conducting fracture zone are 126.8-190.5 m, 232.9-334.5 m and 79.1-98.0 m, 158.2-196.0 m respectively.During mining, the water-conducting fractures will reach the aquifers and the water-resistant strata which leads to a damage to them.It is estimated that the amount of mine water emission is up to 2 050 m³/d during mining of the coal seam.According to the purpose of water use, the distribution of local enterprises and the quality of the mine water, a comprehensive strategies of deposing and utilizing the mine water are proposed, such as the use of manufacturing, the use of living and the use of restoration of surface vegetation.