There are five
different methods of underground coal mining. The first type is the most common
type of mining in West Virginia and it is shaft mining. You have probably seen
these types of mines before because the only way to get down into the mine is
to take an elevator straight down usually past 1,000 feet. The advantages to shaft mining are that we can
get a lot of coal out of the mines with huge machines that do all of the work
but the bad thing is that a massive mine explosion could happen if the company
isn’t carful.
Drift mining- Drift mining is another
method of coal mining where the opening of the mine is in the side of the
mountain instead of drilling down into the ground when the coal seam meets the
surface. The coal miners mine horizontally into the coal seam in the
mountain. Drift mining is one of the
easiest ways to mine but it is always not the safest because of the danger of
collapsing roofs.
Room and pillar mining is an
underground mining method where they cut out sections of the coal and leave
“pillars” in many “rooms” of coal in parts so the coal will support the roof.
The bad thing about these types of mines is the nearly half of the coal that is
used for the pillars is left behind and there is a constant danger of the roofs
collapsing on top of the miners. In room
and pillar mining they can use fewer men to extract coal they can use
continuous machines that constantly cut coal out of the mounting without the
use of multiple miners. It is a huge
machine that has rotating steel drum tungsten carbide teeth that move 5 tons of
coal per minute. Continuous miners are used in drift mining and room and pillar
mining and have been around since the 1940’s. Click here to see a continuous miner.
The last method of underground mining is the long wall
technique. This method is highly
effective because there are hydraulics machines that hold the roof up while
they mine the coal and then after they are all done they retreat and let the
roof collapse on itself. It is high effective but dangers of roof collapses are
still high.
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