While underground mining requires an array of resources, equipment and financial backing, the method is best suited if the environment and coal potential harmonize. Longwall mining accounts for 50 percent of coal mines in the world and is much safer than other methods of coal mining.
The method to be used for underground mining depends on the concentration of ore, strength of the surrounding rock, and the various risks involved. ScienceStruck explains what these methods are, with the applications of each one.
Mine planning is done to maximize the rate of return Underground mine life can be few years - few decades Placement of primary openings is highly dependent on the specific mining method (caving, stoping, room/pillar, etc.) Primary openings are chosen with .
The underground mining methods we use include room and pillar, narrow vein stoping and large-scale mechanised mining. Room and pillar mining is a style of mining where tunnels are driven in a chess board pattern with massive square pillars between them which are gradually cut away as the work .
Coal mining - Coal mining - Underground mining: In underground coal mining, the working environment is completely enclosed by the geologic medium, which consists of the coal seam and the overlying and underlying strata. Access to the coal seam is gained by suitable openings from the surface, and a network of roadways driven in the seam then facilitates the installation of service facilities ...
There are two main methods of underground mining: room-and-pillar and longwall mining. Room-and-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 of the mine.
Advanced mining equipment, like a continuous miner, is used to safely and efficiently remove coal. Typically, a crew of 4 is working underground. They enter the mine on a man-trip — a specially-designed, low-profile mining vehicle — through a 2,400-foot, 16% grade tunnel. It takes 20 minutes to arrive at 1 of the 5 working sections.
outside the mining area for placement and storage. In the Midwest, where the surface topography and coal seams are generally flat, it is common to employ area strip mining in which the fragmented overburden is placed directly by large draglines in the space created where coal has been mined ().In some situations in the eastern United States, a coal seam occurring near the top of mountains is ...
Sep 10, 2012· This video provides a basic description of the room & pillar mining method for extracting coal underground. It includes an explanation of the different products working together in a room & pillar ...
1. Underground Mining Methods 1.1. Classification of Underground Mining Methods Mineral production in which all extracting operations are conducted beneath the ground surface is termed underground mining. Underground mining methods are usually employed when the depth of the deposit and/or the waste to ore ratio (stripping ratio) are too great ...
Apr 27, 2015· Historically speaking, underground mining not only saves the mining area's original form but also gives the mining company higher revenues. According to MiningGlobal, longwall mining, a type of underground mining that utilizes a longwall shearer, accounts for 50 percent of coal mines in the world and is much safer than other methods of coal mining.
methods of working in underground coal mining Productivity Improvement in Underground Coal Mines . Of the total output of coal from underground mines, more than 90% of coal is obtained by the bord and pillar method, the predominant method of mining followed in India, and the rest is mined by the longwall mining method. ...
Shortwall Mining. This method of mining was developed in the late 1960's to take advantage of the then recent development of suitable hydraulic longwall supports, coupled with the productivity and low capital cost of continuous miners and shuttle cars.
The environmental toll of underground mining is significant. It includes air pollution, changes in water-flow patterns, chemical and gas seepage into water supplies and soil, inaccessible fires in abandoned mines, and dramatic changes in land composition that can make the area unusable after the mining operation is done [source: Saxena]. Then there is the human toll.
Retreat mining is a process that recovers the supporting coal pillars, working from the back of the mine towards the entrance, hence the word retreat.Room and pillar mining advances inward, away from the entrance of the mine. Other underground mining methods include Hard rock mining, bore hole mining, drift and fill mining, long hole slope ...
Methods of Working Coal and Metal Mines Volume 3 discusses the extraction of mineral deposits which involves the driving of development openings from the surface or a central shaft to the block out portions of the deposit. Chat Now Best Practices For Dust Control In Coal Mining U.S. underground coal mine .
In any discussion of Methods of Underground Mining Comparison, one is repeatedly confronted with the difficulty of dealing with so many variable conditions. It is not an exact science and in the choice of a method each varying factor has a certain weight, which, in many cases, experience alone can determine.
MINING Engineering Interview Questions and Answers pdf free Downlod MINING Engineering multiple choice Questions mcqs objective type lab viva questions. ... In an underground coal mine the place where explosive is stored in underground is called as. ... Blasting Gallery method is not suitable for working seam thickness. Less than 7 m.
There are hard-rock underground mines, and there are soft-rock underground mines. Coal deposits, for instance, live in relatively soft sedimentary rock. Gold deposits live in igneous or metamorphic rock, which is relatively hard, as do diamonds, copper, silver, nickel and zinc [source: Great Mining].
Underground Coal Mining Methods and Engineering Dust Controls. An underground mine consists of the portals (entrance and exits to the mines), mains, submains, panels, and working faces. The panels are the working sections of the production operation. Depending on the mining method, a working section can have one or more working faces.
Longwall mining is a form of underground coal mining where a long wall of coal is mined in a single slice (typically 0.6–1.0 m (2 ft 0 in–3 ft 3 in) thick). The longwall panel (the block of coal that is being mined) is typically 3–4 km (1.9–2.5 mi) long and 250–400 m (820–1,310 ft) wide.
Underground Coal mining Methods: In underground coal mining, the working environment is completely enclosed by the g eologic medium, which consists of the coal seam and the ov erlying and ...
This paper reviews underground mining methods for total thickness of a thick coal seam in single lift (TTTCSSL). Review shows the required engineering for extraction of thick seams needs to be fitted with thickness of the seam, behavior of rock-mass and surrounding stress conditions for efficient mining.
the mining industry, but took so long to live up to its promise, is a fascinating example of the interaction between economics, technology, regulation, and science. It still has important lessons for today. INTRODUCTION The 20th century was a time of continuous revolution in underground coal mining technology. At the beginning of the