Lesson 3 Coal Surface Mining Flashcards
defined as the process of extracting coal from the ground. Due to its wide use in power generation and application in steel and cement industries several investments all over the world were made to extract it from ground.
Coal mining
Coal mining has had many developments over the recent years, from the early days of
men tunneling, digging, and manually extracting the coal on carts to large open cut and
long wall mines. Mining at this scale requires the use of heavy equipment such as __________.
draglines, trucks, conveyors, hydraulic jacks and shearers.
In the United Kingdom and South Africa, a coal mine and its structures are is called as “_______” which also refers to an underground coal mine in Australia. The term is also used in United States to describe a coal mine operation, but this usage is less common.
colliery
As mining of coal depends on
the _____ and ______ of the coal seams, different techniques are now used to extract the deposits.
depth and quality
What are the factors that are taken into account while selecting the mining method for coal extraction.
Depth, density, and thickness of the coal seam
This method recovers a greater fraction of the coal deposit than underground methods since more coal seams are exposed for extraction using high capacity heavy equipment in this approach.
surface mining methods
One primary consideration in deciding on what mining method should be used.
depth of the deposit
When coal seams are near the surface, it may be economical to extract the coal using ___________, also referred as open cut, open pit or open cast.
surface mining methods
An equipment which operate by removing the overburden
Draglines
An equipment which transport overburden and coal
power shovels and large trucks
In order to access the coal seam, overburden should be stripped first by breaking it through blasting then removing it using draglines or by shovel and truck.
Removal of overburden
Identify the process. Once the coal seam is exposed, it is drilled, fractured and thoroughly mined in strips. The coal is then loaded onto large trucks or conveyors for transport to either the coal preparation plant or directly to where it will be used.
Extraction and Hauling of Coal
Most open cast mines in the United States extract _________ coal, where ____% of its coal production is delivered through ____________.
bituminous, 67%, surface mining
Surface mining accounts for around ___ percent of production in Australia.
80
In the Philippines, ___% of the country’s coal production is produced by ________________, an open pit mine and the largest coal producer in the country.
92, Semirara Mining
Corporation
In this method, coal seams are exposed by removing the surface or overburden above them in long strips.
Strip Mining
The overburden taken out from the first strip is deposited outside the mining area. This process is referred to as ______________. The void resulting from the first strip and the coal mining is used to deposit overburden from the subsequent strips.
out-of-pit dumping
What are the two forms of strip mining, which is often used to extract coal and lignite?
Area strip mining and contour strip mining
In _______________, bulldozers
or power shovels are deployed to take away huge amounts of ground material in terraced strips for extracting coal from a seam on a hill
contour strip mining
It is commonly used on flat terrain to extract deposits spread over a large area.
Area strip mining
This method is applied for mineral deposits situated near the peaks of a mountain but too deep to be extracted by drilling tunnels from the sides.
Mountain-top removal
Mountain-top removal is widely used in the _________ coal fields of West Virginia, Kentucky, Virginia and Tennessee in the US.
Appalachian
This method involves removal of
the mountaintop overlying the coal seam by ________ and _________.
blasting and hauling
In this method ore is removed by digging a pit in the ground. It is normally used when the rock layer above the ore is too weak to allow underground tunnels and when ore deposits are lying under thin rock which can be easily removed by digging benches.
Open-pit Mining
In Open-pit Mining, __________ are dug around the circumference of the pit to remove ore from the sides. When ore can no longer be removed from one bench, a new one is dug at a lower level.
circular benches
The equipment used for Open-pit Mining method is mostly restricted to dump or haul trucks, and shovels, though conveyors. Why is that?
It can quicken the process.
refers to a method of removing coal, clay, phosphate, oil-shale,
etc. from thin seams exposed in deep trenches or high-walls in strip mines using an auger.
Auger Mining
The auger consists of two principal pieces. What are these?
Cutting head and prime mover
A piece in auger where generally from 1.5 to 8 feet in diameter. It may be single or multiple.
cutting head
A piece in auger usually a skid mounted carriage, providing a mounting for the engine, drive head, and controls
prime mover
