Hydrogeological Feasibility Study Of Next Group Coal Mine In Xiaotun Colliery Fengfeng Coalfield

Coal resource is an important part of China’s energy. In recent years, with theincreasing demand for coal resources and the ceaselessly increasing exploitation strength ofcoal resource, shallow coal resources (Group coal) decrease with each passing day. Toextend the mine life, mining the next group coal is on the agenda. In North China coal fieldarea, the main aquifer that affect the mining of the next group coal is Ordovicianlimestone.With the increasing of mining depth, the Ordovician limestone water pressure ofseam floor is also growing and the threat of Ordovician limestone water to the mining ofthe next group coal grows. So the hydrogeology feasibility study of the mining of the nextgroup coal has important significance. Xiaotun Colliery is located in Fengfeng coalfield andis divided into two parts——the former area and the expand area. Currently the miningcoal is group coal (Da Coal, Yeqing Coal and Shanqing Coal) and the annual output is0.8million tons.By the end of2010, the actural recoverable reserves of coal is only25.23billion tons. The group coal of the former area is exhausted and the mining conditions ofthe expand area are not ready. The next group coal (coal, coal in Xiaoqing and lower framecoal) of the former area has not been mined for the threat from the confined water inOrdovician limestone. For the maintenance of mine production status, mining the nextgroup coal is in imminent. Combination of mine hydrogeological condition, this articlemainly discuss the work:(1) According to Ordovician limestone water test in1996,analysis the recharge, runoff and drainage conditions in Ordovician limestone to providehydrogeological basis for mining the next group coal safely;(2)According to the drillingdata, use the water inrush coefficient method to predict the water inrush of the shallow nextgroup coal (Xiaoqing coal, Daqing coal and Xiajia coal in level-190m) and the forecastresults as follows: in the former area of Xiaotun Colliery, water inrush coefficient ofXiaoqing coal is less than the value of0.06Mpa/m which is the experience value insouthwest and it is greater than the experience value in northeast; the water inrushcoefficient of Daqing coal and Xiajia coal were greater than the value of experience in theformer area. It will have the water inrush risk to mining the next group coal if you do nottake preventive measures;(3) Propose water control measures of mining the shallow nextgroup coal, drain water away from Ordovician limestone to reduce its hydraulic presure tominging the next group coal and analyze its economic benefit.