Research On600-meter-level Shaft Drainage Technology At Qing Shuiying Coal Mine

As one of the main ways of development work in coal mining, vertical shaft has to meetmore difficult during the construction such as the increasing of aquifer, water yield and minepressure which caused by the extend of the shaft. The Eastern Ningxia Mining Area has abatch of deep shaft with large diameter in construction now; these shafts will through the waterenriched strata of Quaternary, Cretaceous, and Jurassic and so on. the strata are widelydistributed in the northwest region of China, so the research on shaft drainage technology can tonly lay the foundation for the creation of drainage sinking technology but also is of greatsignificance for the construction and development of western mine.Taking the assistant vertical shaft of Qingshuiying coal mine in the Eastern NingxiaMining Area as object, and using the orthogonal experiment to analyze the precipitationparameters of group wells by numerical analysis software Modflow, the article has studied theinfluencing factors of precipitation seepage field of group hole has been studied, and thedrainage design and prediction calculation has been carried and the actual effect is evaluated.The results are shown as follow:1. When group well precipitation, the limit dropdown impact factors according toimportance in order is strata permeability coefficient, well number, well diameter. Limitdropdown decreased with the increase of permeability coefficient while single-hole limit flowdecreased with the increase of hole number. Contrast the above factors we can see that theeffect factors on the impact of precipitation in order as follows: Pumping well number>Precipitation area radius> Pumping time and generally pumping time in two to three monthsis best.2. In Qingshuiying coal mine, three wells is taken for drainage and pumping flow is13.3m3/h. During actual precipitation process, the water inflow may get almost12m3/h, and increases gradually with the increase of excavation depth. After the hydrophobic roadwayexpedited, the water inflow will get480m3/h, it not only can reduce the strata water headeffectively, but also is beneficial to hydrocephalus emissions of center well.3. The secondary pore forming technology of deep precipitation well is formed and theultra deep well drainage pipe and filter material comprehensive down process is improved,and the deep hole pumping equipment system installation process and the Precipitationequipment operation and maintenance technology is made clearly. The technical andeconomic comparison between drainage method and freezing method show that the drainagemethod has obvious advantages.