Numerical Analysis of Top Coal Recovery Ratio by using Discrete Element Method

Niaz Muhammad Shahani, Zhijun Wan, Li Guichen, Fahad Irfan Siddiqui, Abdul Ghani Pathan, Peiju Yang, Sifei Liu


There is a massive quantity of lignite coal reserves at the Thar Coal Mine Pakistan which are demarcated through thick coal seams. To extract these thick coal seams, the chosen method for mining is Top Coal Caving. The Longwall Top Coal Caving (LTCC) has been the preferred underground mining method that has been developed and then accepted by its guaranteed results in China’s coal mining industry. In this research paper, a 12 meter thick coal seam has been modeled successfully and the mechanism of top coal demonstrated and top coal recovery ratio was computed with the help of the Discrete Element Method (DEM) at Block-IX Thar Coal Mine. In the modeling consequences, the total top coal recovery ratio was computed to be 83.9% when the top coal thickness was three times as the height of cutting height with the drawing interval of 0.8m respectively. Thus, this recovery ratio suggests proficient production for the development of LTCC method at Thar coal mine Pakistan.

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