advantages and disadvantages of mining

 

Advantages/Disadvantages

Underground mining- more expensive than surface mining; takes longer to get minerals out; uses less blasting and drilling, and sends less miners underground;

Drift mining- less energy is required to transport miners and heavy equipment, safer transportation because the use of horizontal direction, cheaper and safer than shaft mining.

Shaft mining- is the deepest underground mining; has a vertical manshaft; safer when closing the mine. 

Room and pillar mining- uses pillars of coal to hold up the roof; pillars are mined when the mine begins closing; careful

Continuous mining- uses continuous mining machine to cut coal from walls; companies choose to use this method because they believe it is best.

Long wall mining- uses a machine call continuous miner to slice layer of coal or minerals from the walls, highly efficient.

Surface mining- mining minerals, gemstones, and rocks that are close to the surface; cheaper, can recover more of the resource; is safer and can use larger-scale mining equipment offering higher production rates; its high visibility, the large-scale surface disturbance and the limited economic depth to which mining can take place.

Strip mining- ends up hurting the area around the mine

Mountaintop mining- makes huge changes in the land that’s mined and the area around it; top of the mountain, the water flow, and the environment of and around the mountain are destroyed; causes problems in water supply, water quality, and watersheds

 

 

surface mining

Surface Mining

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1.      Strip mining- used when coal is near the surface or overburden is unstable; as mining process, the overburden is placed in the previous mine cavity.

2.      Contour mining- a type of strip mining; follows contour of a hill leaving a terrace in mountainside.

 

 

 

 

3.       Mountaintop mining- tops of hills are removed to access horizontal coal seams; overburden is pushing to areas between high elevations; follows reclamation; most controversial mining method.

 

 

underground mining

Underground Mining

1.      Drift mining- is possible where the coal steam intersects with the surface; mine enters the seam in a horizontal direction following the coal.

 

2.       Shaft mining- is a common method; accessing coal seam in which elevators provide access to the mines; commonly deeper than 1000 feet below the surface.

 

 

3.      Room and pillar mining- nearly half of the coal is left behind to support the roof; pillars “squeeze” putting pressure of adjacent pillars leading to roofs collapse.

 

 

4.       Continuous mining- continuous mining machines can be used with drift or room and pillar mines.; one miner can operate a continuous miner to a rotating steel drum with tungsten carbide teeth to mine 5 tons of coal per minute; some varieties of continuous mining machines have been in use since the 1940s.

 

 

 

 

 

 

5.      Long wall mining- highly efficient; huge mining machines support the roof as it also removes coal; when coal is fully removed, the machine is removed and the roof collapses; highly productive underground coal mining technique

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