While numerous mining companies conduct surface mining at their sites, as ore deposits run deeper the associated costs can become prohibitively expensive. One particular indicator is the strip ratio, or the number of waste materials in units that a mine site must remove in extracting one unit of ore. Mining operations that are subject to a larger strip ratio can turn to underground mining as a more cost-efficient and land-friendly investment.
The Objective of Underground Mining
Underground mining can extract ore from the earth in a safe and economical way without producing too much waste. Underground mines are often developed with a number of roughly horizontal levels at various depths beneath the surface, which miners can easily access with underground mining cars, rail haulage, and multiple drill units. To support the ceiling on rooms or stopes where ore or other minerals are extracted, pillars are often left in place.
Hard Rock and Soft Rock Underground Mining
Different underground mining methods are utilized for excavating different types of minerals. Underground hard rock mining utilizes techniques to extract hard minerals, while soft rock mining specializes in the extraction of softer materials such as coal. In the case of hard rock mining, methods like cut and fill, drill and fill, and room and pillar mining are used. Longwall mining, blast mining, and shortwall mining, on the other hand, are methods often used for soft rock mining.
Ventilation and Safety Concerns
Both types of underground mining place high regard to mine safety, and providing adequate mine ventilation is one of the top priorities. This involves supplying miners with constant fresh air, while removing noxious gases and dangerous dusts that may cause health issues.
For mining companies specializing in the extraction of ore, underground mining may yield a considerably less amount of ore compared to that of a surface operation. Ore from underground, however, tends to have a higher grade than ores found in planar zones making underground mining methods financially feasible. Extracting minerals in underground operations can be made more efficient with the use of mining ore cars and other conveyance equipment provided by manufacturers like Wabi Iron & Steel Corp.
Underground Mining Methods, InsideMetals.com
Underground Mining, GreatMining