Surface and mountaintop mining

Date: 2015-10-07; view: 442.

Methods of extraction

B. COAL MINING

Coal mining is the extraction of coal from the earth for use as fuel. A coal mine and its accompanying structures are collectively known as a colliery.

The most economical method of coal extraction from coal seams depends on the depth and quality of the seams, and also the geology and environmental factors of the area being mined. Coal mining processes are generally differentiated by whether they operate on the surface or underground.

If the coal seams are near the surface, the coal is extracted by strip mining. Strip mining exposes the coal by the advancement of an open pit or strip. As the coal is exposed and extracted, the overburden from the still covered coal fills the former pit, and the strip progresses. Most open cast mines карьер in the US extract bituminous coal. In South Wales open casting for steam coal and anthracite is practised.

Mountaintop removal is a form of surface mining that takes place at the topmost portion of a mountain. Utilized for the past 30 years, mountaintop mining involves removing the highest part of the mountain for the maximum recovery of coal. The process is notorious for destruction of entire ranges. So is the practice of hollow fills, or filling in valleys with mining debris, covering streams and disrupting ecosystems.