Analysis On Effect Of Water Resources And Ecological Environment Based On Excavate Coal

Irrational exploitation of coal resources caused series environmental geologyissue, such as groundwater recession, land subsidence, collapse, geomorphologiclandscape ruin, surface (ground) water damage, ecological degradation, landdesertification and so on. It could bring serious damages to the weak ecologicalenvironment in the west area. Based on the height of diversion fissure zone causedby the mine exploration and the factors arose from geology and environmentalgeology, this study is used analytic hierarchy process to regionalize the study area.The regionalization is aiming at the effect of water resources and environmentalgeology caused by coal mining. It could meet requirements of the high quality andenvironmental friendly coal resources in coal chemical industry in Ningxia. Thisstudy provides scientific evidences to forecast the geological disasters by thedevelopment and construction process of coal exploitation and to develop theresources and protect the environment of energy base in the east of Ningxia.The surface collapse mechanism and the ecological environment effects causedby coal mining were discussed in this study to analysis the applicability of criticallayer for the study area. To locate the critical layer on the overlying rock in the studyarea, the concept and determination of critical layer and loading control layer wereused. Moreover, the height of diversion fissure zone growth was obtained accordingto analyzing the critical layer by computing method of combined load and dynamicchanging process of loading control layer by propelling the working face. The mainconclusions of this study are as follows:(1) The maximum negative displacement of overlying rock after coal mininghas little effected by Poisson ratio, and it was in directly proportional to cover depthand mining depth and be inversely proportional to elasticity modulus and C values.(2) Based on the motion and fracture rules of overlying strata in the coal miningarea in Ningxia east and the growth characteristics of diversion fissure zone, thediversion fissure zone was not made any progress until evolving to NO.18rock stratum. It was by the reason of the lack of free space under NO.18rock stratum.The safety height of coal mining was230m, which determined by rock compressivestrength and rock type of top and bottom board in coal seam, and coal bed pitch.Empirical data of energy base in Shanxi was contrast to the results computing byempirical formula to make sure the safety height.(3) The analytic hierarchy process and overlapping method of ArcGIS was usedto divide the study area into three parts: Key protective zone: the junctionbetween southern part of Qingshuiying underground mine field and Meihua field; Ordinary protective zone: north-central of Qingshuiying field, most part of Meihuafield and north of Shicaocun field; Non-protective zone: northern and middle partof the field.