What is chain pillar in longwall mining?
Chain coal pillars are parts of the structure of longwall mining system that play a significant role in the stability of the entries. With mechanization and developments in the various aspects of the method, higher efficiency in optimization of the design of chain coal pillars seems appropriate.
What is longwall method in mining?
longwall mining Longwall mining is an underground method of excavating coal from tabular deposits, as well as soft mineral deposits such as potash. Large rectangular blocks of coal are defined during the development stage of the mine and are then extracted in a single continuous operation.
Why is longwall mining bad?
Longwall mining can result in geological disruptions in the rockbed, and can in turn affect water movement and result in water moving away from the surface, through the mined area, and into the aquifer. A resulting loss in surface water can negatively impact riparian ecosystems.
What is bord and pillar method?
A system of mining in which the distinguishing feature is the winning of less than 50% coal on the first working. It is more an extension of the development work than mining. The second working is similar in principle to top slicing.
What is bord and pillar mining method?
One of the oldest methods of mining is the Bord and Pillar. It is a method in which the mined material is extracted across a horizontal plane while leaving “pillars” of untouched material to support the overburden leaving open areas or “rooms” underground.
Which technique is used in bord and pillar mining method?
Fundamentally, the bord and pillar method of mining coal seams involves the driving of a series of narrow headings in the seam parallel to each other and connected by cross headings so as to form pillars for subsequent extraction, either partial or complete, as geological conditions or necessity for supporting the …
What is a Bord in mining?
The word “bord” is not a misspelling of “board”, but a mining term for an underground space or room created to access the coal deposit. It originally meant a face of coal parallel to the natural fissures.
