Numerical Modelling Of Longwall Top Coal Caving Method At Thar Coalfield

Research investigations have shown that there is an extensive quantity of lignite coal reserves at the Thar Coal Pakistan which are outlined through thick coal seams.To be able to get to these thick coal seams,the preferred mining method is the Longwall Top Coal Caving(LTCC).Specifically,this has become the accepted method for extracting thick coal seams,ably supported by its guaranteed results in China’s coal mining industry.Furthermore,researchers around the world have continued to find ways to improve the LTCC method.In this research study,a 12 meter thick coal seam has been modeled successfully,and the mechanism of top coal demonstrated,stress values and top coal recovery ratio were computed with the help of the two advanced software,i.e.UDEC and PFC at Block-IX Thar Coalfield.In the simulation results,the maximum vertical abutment stress of 20 MPa was discovered 6 meters in front of the face at cutting to caving height ratio 1:2 and 3 meters at 1:3.Through a comprehensive study,the existence of top coal shows that a 12 meter thick layer of coal can be easily caved behind the face.On the contrary,the top coal recovery ratio was successfully computed with the help of the Discrete Element Method.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.Hence,cutting to caving height and top coal recovery ratio at 1:3 suggests very efficient production for the development of the LTCC method of thick coal seams at Thar Coalfield Pakistan.