Detailed Knowledge of Mobile Coal Crusher Three

Large opencast mines can cover an location of several square kilometres and use very large pieces of equipment , including:

* draglines, which remove the overburden

* power shovels

* large trucks, which transport overburden and coal

* bucket wheel excavators

* conveyors

The overburden of soil and rock is initial broken up by explosives; it is then removed by draglines or by shovel and truck. Once the coal seam is exposed, it is drilled, fractured and systematically mined in strips. The coal is then loaded on to large trucks or conveyors for transport to either the mineral separation plant or direct to where it will be utilised.

Underground Mining

There are two main strategies of underground mining: room-and-pillar and longwall mining.

Room & Pillar Mining

In room-and-pillar mining, coal deposits are mined by cutting a network of ‘rooms’ into the coal seam and leaving behind ‘pillars’ of coal to support the roof in the mine. These pillars can be up to 40% in the total coal in the seam – although this coal can sometimes be recovered at a later stage. construction waste recycling crushing plant

Longwall Mining

Longwall mining involves the full extraction of coal from a section of the seam, or ‘face’ using mechanical shearers. A longwall face requires careful planning to ensure favourable geology exists throughout the section before development work begins. The coal ‘face’ can vary in length from 100-350m. Self-advancing, hydraulically-powered supports temporarily hold up the roof while coal is extracted. When coal has been extracted from the area, the roof is allowed to collapse. Over 75% of the coal inside the deposit can be extracted from panels of coal that can extend 3km through the coal seam.

Technological advancements have made coal mining today additional productive than it has ever been. To keep up with technology and to extract coal as efficiently as possible modern mining personnel must be highly skilled and well-trained in the use of complex, state-of-the-art instruments and equipment.

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