Search results
Results From The WOW.Com Content Network
Retreat mining is the removal of pillars in the underground mining technique known as room and pillar mining. In the first phase of room and pillar mining, tunnels are advanced into the coal or ore body in a rectangular pattern resembling city streets. Pillars are left between tunnels to support the weight of the overburden. The first phase is ...
Room and pillar mining was one of the earliest methods used, [3] although with significantly more manpower. The room and pillar system is used in mining coal , gypsum , [ 4 ] iron , [ 5 ] limestone , [ 6 ] and uranium [ 7 ] ores, particularly when found as manto or blanket deposits, stone and aggregates , talc , soda ash , and potash . [ 8 ]
A drum hoist (steel wire rope visible) and motor. In underground mining a hoist or winder [1] is used to raise and lower conveyances within the mine shaft.Modern hoists are normally powered using electric motors, historically with direct current drives utilizing Ward Leonard control machines and later solid-state converters (), although modern large hoists use alternating current drives that ...
Remote-controlled continuous miners are used to work in a variety of difficult seams and conditions, and robotic versions controlled by computers are becoming increasingly common. Continuous mining is a misnomer, as room and pillar coal mining is very cyclical. In the US, one can generally cut up to around 20 feet (6 meters).
Mining of sulfur from a deposit at the edge of Ijen's crater lake, Indonesia. Mining is the extraction of valuable geological materials and minerals from the surface of the Earth. Mining is required to obtain most materials that cannot be grown through agricultural processes, or feasibly created artificially in a laboratory or factory.
The hammer and pick, two basic tools traditionally used in mining for breaking rock, together form a main heraldic symbol of mining and miners. It is also used to mark the location of mines on maps. In other locations, the pickaxe and shovel fill the same purpose. The following outline is provided as an overview of and topical guide to mining:
2021 uranium mining by nation [1] Schematic diagram of stages from uranium mining to energy production. Uranium mining is the process of extraction of uranium ore from the ground. Over 50,000 tons of uranium were produced in 2019. Kazakhstan, Canada, and Australia were the top three uranium producers, respectively, and together account for 68% ...
Ivan 'Ironman' Stewart's Super Off Road is an arcade video game released in 1989 by Leland Corporation. [1] The game was designed and managed by John Morgan who was also lead programmer, and endorsed by professional off-road racer Ivan Stewart .