Feasibility Study On Mining Coal Resources Under West Side Slope Of Heidaigou Open Pit Coal Mine’s First Mining Area

Open pit mine always left a large number of coal resources under the end slope,and it easily make a waste of resources which is caused by can’t efficiently and timelyrecover. Considering the circumstance of most surface coal mine had advanced tolong way and the coal seam fitted with surface mine was thick, the resources wasteconsequence is becoming concerned by mining enterprises and government.Heidaigou open pit coal mine s first mining area was advanced to the second, beingconfronted with the steering work. This condition is opportune to mine the coal seamunder west side slope. The main purpose of this paper was exploring the feasibility ofrecycling coal resources under surface mine’s side slope integrated with thegeological conditions, status of open-pit mining and existing coal mining technology.First, this paper analyzed and summarized the special geological propertiesinvolved seam’s thick, narrow strip caused by surface mining, side slope was coveredby internal dump’s rocks.Secondly, explore the viable coal mining program which match to particularityconditions of the coal in the end working slope area based on the existing miningmethods. In this part, This paper firstly discusses the feasibility of open pit miningmethods to mine the coal seam under the end slope, and get the result of being notfeasible. After that, the feasibility of coal seam under the end slope is analyzed aroundthe underground mining method, including four programs: drift development systemused internal dump pit program, decline shaft development system at side slope’smiddle length (3#crushing plant site), raise development system at side slope’smiddle length (3#crushing plant site), development system of three minefield. thenusing Analytical Hierarchy Process to analyze the programs’ excellence, the result is:development system of three minefield four program is the best. Primary fiveelections of mining method are fully mechanized coal mining stratification, capestratified mining, double sub-level caving, constant hearth stratification upstreammining. Then use fuzzy comprehensive evaluation to study the suitability of themethods, the result is that double sub-level caving method is the best. At the last,explore the feasibility of special mining methods of underground gasification andCWS underground extraction of surface preparation.