The Research On Rational Mining Method Of No.4Seam Of Longquan Coal Mine

The appropriate choice of mining method means very important to the mine production levels and economic benefit. The Main mining method in thick seam in China have3, they are slicing mining, large mining height, top coal caving method. Slicing is gradually being phased out in the6m seam, top coal caving has developed more than20years, it is more mature technology theory. The development of large mining height is recent10years.The No.4seam of Longquan coal is the main mining seam, deep450m,6.47m average coal thickness. Geological structure is simple, and it has a Hydro-geological conditions. No.4seam Belongs to high gassy, seam spontaneous combustion tendency of class ii. A mine construction scale is of5million tons.Under the condition of6m seam, China with annual output of up to tens of millions of tons of examples with large mining height and an annual output of more than5million tons of coal caving for instance. From the perspective of thick coal seam mining technology, the development experienced by the slicing mining, top coal caving, and large mining height3stages. Longquan mine raised the issue of the top coal caving and large mining height which is the better choice, commissioned a feasibility study on mining method of Taiyuan University. According to the development of mining technology, it seems that the use of large mining height coal mining methods is better. But relative to the selection of the mining method, restriction of coal seam occurrence conditions and technical specifications, it needs specific analysis.Longquan mine Located in Loufan County in Shanxi province. for the No.4seam geo-mechanical condition, Papers with theoretical analysis, field observations, numerical simulations and experimental research and engineering means of analogy, we have a System analysis of the advantages and disadvantages and feasibility of top coal caving and large mining height. Do the main work is as follows:1.The project specially commissioned geologic prospecting team separately in the main inclined shaft of auxiliary inclined shaft and1000meters diameter67mm down two sets of drill, each set of deep drilling core40m. Draw a histogram core, and measured in the laboratory roof and floor of coal rock mechanical parameters.2. Through the collection and analysis of domestic6m in thick coal seam mining method instance, summed up the mining method of the General conditions, Engineering analogy of mining method has been made on the Longquan No.4seam. 3. we made a A detailed analysis of Occurrence conditions on impact of coal mining method of No.4seam,, come to the Falling performance of No4seam is very good, it is suitable for top coal caving and top coal recovery rate is higher than the large mining height and statistics better than the conclusion of high mining height;4. we used the numerical methods to analysis the coal wall spalling and rock damage of6m coal seam, under the condition of large mining height, concluded working resistance of support size less effects to surrounding rock in No.4seam, working resistance under the condition of12000KN has a poor function on the stability of coal wall.Study on the combination of the above, we believed that Longquan No.4seam choose the top coal caving mining method is a good choice. Although below the large mining height on gas safety, but both avoid sloughing roof fall to ensure normal production, is also on the recovery rate and economics are better than large mining height and finalized with top coal caving mining method.