Longwall mining is a form of underground coal mining where a long wall of coal is mined in a single slice (typically 0.6–6.0 m (2 ft 0 in – 19 ft 8 in) thick). The section of rock that is being mined, known as the longwall panel, is typically 3–4 km (1.9–2.5 mi) long, but can be up to 7.5 km (4.7 mi) long and 250–400 m (820–1,310 ft ...

Longwall mining is recognized for its high level of productivity and efficiency. Unlike traditional room and pillar mining, which leaves behind coal pillars to support the mine roof, longwall mining extracts more of the coal seam, with recovery rates that can exceed 75%.

Longwall mining is a highly productive underground coal mining technique. Longwall mining machines consist of multiple coal shearers mounted on a series of self-advancing hydraulic ceiling supports.

Longwall mining is a fast and mechanized method of coal mining where a large “wall” of coal is mined with a high-powered cutting system and the coal is transported out of the mine through a network of conveyors.

Sep 4, 2012 · Longwall mining of coal is a high production and high productivity method, employing sophisticated electrical, mechanical, and hydraulic systems, as well as computer-based monitoring and control systems. Most modern (coal) longwall faces are semi-automated.

Longwall mining, a type of practice consider “full extraction” nets more coal with fewer miners than traditional techniques and causes extensive damage to residences and water supplies of those living above the mines.

LONGWALL MINING Overview. In the method of secondary extraction known as longwall mining a relatively long mining face (typically in the range 100 to 300m but may be longer) is created by driving a roadway at right angles between two roadways that form the sides of the longwall block, with one rib of this new roadway forming the longwall face.

Longwall mining and room-and-pillar mining are the two basic methods of mining coal underground, with room-and-pillar being the traditional method in the United States. Both methods are well suited to extracting the relatively flat coalbeds (or …

In the longwall mining method, mine development is carried out in such a manner that large blocks of coal, usually 100 to 300 metres wide and 1,000 to 3,000 metres long, are available for complete extraction (see photograph ).

In longwall mining, a panel of coal, typically around 150 to 300 metres wide, 1000 to 3500 metres long and 2 to 5 metres thick, is totally removed by longwall shearing machinery, which travels back and forth across the coalface.