Room and pillar and longwall are two dominant methods that account for the vast majority of underground coal mining (Kanchwala, 2018).
In room and pillar mining, seams of the coal are mined partially, leaving large pillars of coal intact in a bid to support the overlying layers of rock.
In contrast, longwall mining involves cutting long tunnels into a coal seam and removing the extracted coal using an arrangement of conveyor belts. A temporary hydraulic support system is installed to hold the rock ceiling in place as the miners and machinery move along the coal seam(Kanchwala, 2018).
Longwall mining is a very efficient coal producing technique. It’s productivity is potentially higher than that of room-and-pillar mining, because longwall mining is basically a continuous operation requiring fewer workers and allowing a high rate of production to be sustained (Pontus, n.d.).
Longwall mining has better resource recovery (about 80% compared with about 60 percent for room and pillar method) and safety of the miners enhanced by being under the hydraulic roof supports when they are extracting coal(Longwall Mining, 2021).
Overall, longwall mining offers more opportunities for automation(Pontus, n.d.).
What do you think makes longwall mining’s higher coal recovery (its continuous operation, advanced equipment, or something else) the most game-changing for underground coal mining?
