SAIKAT MONDAL
MINING ENGINEERING
7th SEMESTER
Exam Roll No-110912001
Subject- Seminar
Abstract
The importance of mining is definitely significant to human civilization. In India many of the underground coal mine operated by conventional bord and pillar system. Main disadvantage of this system is that percentage of recovery is very less. These loos can be minimized by adopting shortwall method of working at the time of pillar extraction. In India some of the underground mine adopting this method at the time of depillaring and percentage of extraction is very high and production rate is also encouraging. So we should adopt this method in all underground mines where geomining condition support. Keywords Longwall,shortwall,depillaring.
Introduction:
Mining is the extraction of valuable mineral or any other geological mineral from the earth. The first mining operation started at the beginning of human civilization. Modern mining operation consists of prospecting of ore bodies, reserve estimation, detailed geological study, profit calculation, ore or coal extraction by any process and after the ending of mining process reclamation of the mining area. Coal/Ore may be extracted by Open pit or Surface mining method and Underground mining method. The different underground mining methods used in India for extraction of coal are conventional method i.e. Bord and Pillar method, Longwall method, Shortwall method, Miniwall method etc. In India about 90% of U/G coal output is obtained by Bord and Pillar method and barely about 10% around by Longwall and other method. Bord and Pillar method is a conventional method but main disadvantage of this method is that in this method percentage of extraction is very less than other mining methods because a considerable amount of coal is lost in rib pillar which is left