Surface mining is used for an estimated forty% of coal production. Used equipment equipment can be used to extract coal. Extracting coal is inexpensive if it’s discovered close to the surface. Once coal is extracted, the topsoil is then replaced and native trees and vegetation is planted to restore the unique condition. There are three various kinds of surface mining: contour, strip, and mountaintop removal mining.
1- Contour Mining: Contour Mining is most commonly utilized in areas that have steep or rolling terrain. It includes digging the earth above the coal line, or coal seam, along the contours of the hilly terrain. This method might be harmful because it might cause landslides and erosion problems.
2- Strip Mining: Strip Mining usually happens on flat terrain. The earth is dug up in long cuts or strips until the coal seam is exposed. After the strip has been drilled and blasted and all the coal has been eliminated, a new strip is created proper subsequent to it and the process continues.
3- Mountaintop Removal Mining: Mountaintop Removal Mining entails using a combination of Contour Mining and Strip Mining. The mountaintops are eliminated to show the coal beneath and the coal is extracted.
Belowground Mining Strategies
If the coal seams are too deep beneathground, then deep beneathground mining is necessary. Deep underneathground mining methods embody Continuous, Longwall, Blast, Retreat Mining and Shortwall Mining.
o Continuous Mining: A machine that has a big rotating metal drum with tungsten carbide enamel scrapes coal from the seam. Conveyors are used to transport the removed coal. About 5 tons of coal might be mined per minute. Accounts for about forty five% of underground coal production.
o Longwall Mining: A classy machine that has a rotating drum that mechanically strikes back and forth along the seam. Loosened coal falls on the pan line which takes the coal to the conveyor belt. Accounts for about 50% of coal production.
o Blast: An older mining method that makes use of dynamite and explosives to break away the coal seam. Accounts for lower than 5% of coal production.
o Retreat Mining: Some of the dangerous coal mining methods. Pillars are used to hold up the mine roof as Coal Mining Property is extracted. The pillars collapse as miners retreat.
o Shortwall Mining: Similar to longwall mining. Uses a steady mining machine with transferable roof supports. The machine shears coal panels about 2.0 ft vast and half a mile long.