* Different aspects of an underground mine.
* Most common methods of underground mining
Underground mining can be soft rock or hard rock.
Soft rock mines, such as coal, do not need the use of explosives for mining. These rocks can be cut with the tools provided by modern technology. They are also soft rock salt, potash, bauxite.
In hard rock mining, the extraction is done by drilling and blasting. First drill holes are made with compressed air or hydraulic. Then holes are inserted in the holes and cause an explosion to fracture the rock. Blasted rock is loaded up large inclination galleries, by which the rock falls into a manhole. They load into containers called Buckets and is removed from the mine.
Different aspects of an underground mine.
* If the operation is to be performed at lower bounds of the land base, then access to the work will be done by a well (shaft) or ramp (spiral decline, decline). The wells serve several functions, including allowing access of personnel mine output, ventilation of the work by injecting air from the surface, and of course, the transport of extracted material to the surface. The ramps themselves have been gaining popularity with great speed in modern mining. These allow direct access to the mine of footage, which facilitates the transport of mineral workings.
* Within have mine galleries, they can be in direction (mineralized mass; drifts) or perpendicular thereto, that is, transverse (cross-cuts).
* The connection between the different levels of a mine is by inclined shafts (raise, upward; winze down), which serve for the transfer of mineral and staff turnover.
* We will have production levels, and below these, ore transport.
* Among the most common devices are the miners (miners), Jumbo drills, transport equipment type LHD (load-haul-dump: cargo-transport-discharge), etc..
Different aspects of an underground mine.
Most common methods of underground mining
Sublevel caving (sublevel stoping) is the method for steeply dipping mineralized bodies (usually reefs). The width of gallery may or may not coincide with that of the ore body. The shot (paste) is prepared by drilling vertical mesh.
Sublevel caving (sublevel stoping). The last rock blasting was performed in the upper sublevel. The next will be at the bottom. Note the radial diagram shooting.
The improvement in drilling systems achieve allowed increasing distances (30 or more meters), which in turn enabled the longhole stoping method implementation for large ore bodies and strong power dip. This method allows cameras to generate 50 m high (more than the height of the School of Geosciences: UCM). Unlike sublevel caving method, a slice is draw whole body simultaneously. The shot is made from several sublevels drilling, fan or radial diagram.
Longhole stoping. Note the chart range from shooting in two galleries.
Room and pillar (room and pillar) is used in bodies with little horizontal or dip (cloaks). Rock pillars are left to support the roof of the chamber. These can be arranged on a regular basis (room and pillar ss) or irregular (casual pillars, or room and pillar sl).Room and pillar method (room and pillar). In this case the columns follow a regular spacing.
Storage harvests (shrinkage stoping) is used in dip strong bodies (veins), having a support encajante needed. As you move the stoping is pulled back up material below.
Storage harvests (shrinkage stoping). As one moves up, extracting the ore be pulled under.
Cameras with stuffing (cut and fill) operates with a system similar to storage harvests, with the substantial difference that the filling is not done with the same mineral started, but with materials that are brought from outside, for example, silt or sand . They can also be used for this purpose the sterile flotation plant, which has many environmental advantages. The method of shoring square (square stoping September) is very laborious and today hardly used. Similar to the process of filling chambers, but also uses a skeleton (lattice) of rectangular boxes.
Cameras with stuffing (cut and fill). Unlike the previous method, the filling
Sinking of blocks (block caving) is ideal in large irregular bodies such as porphyry copper deposits. The technical requirement is that the rock is easily sink fragmenting. There are three main levels: Sink, hash (grizzlies) and transport.
Sinking of blocks (block caving) (section).
Sinking of blocks (block caving), 3D diagram. Each block can have dimensions on the order of 20 to 50 m square at the base and over 80 in the vertical.
Sinking of floors (sublevel caving) is used when the rock is not readily fragmenting. Somewhat reminiscent of sublevel stoping method with the exception that the walls are the same ore body, and these become collapse.
Floors collapse (sublevel caving), general scheme.
An underground tunnel is a work of linear communication aimed at two points, for transporting people, materials and more. Usually it is artificial.
The tunnels are constructed by digging in the ground, either manually or with machines. Common systems are mechanically underground excavation, blasting and manual:
* The mechanical means by timely leafminer (chaser), miner full section or TBM (Tunnel Boring Machine) or with conventional equipment (jackhammer, excavator …)
* Drilling and blasting with explosives.
* Manual, method derived from coal mining classical Asturian basin, which bite with operators jackhammer digging section and another batch of desescombran workers manually or semi-manually.
A well is a hole or tunnel drilled in the ground vertically to a depth sufficient to achieve what is sought, usually a groundwater reservoir (originally) the water table or materials such as oil (oil well). Generally cylindrical in shape, are usually taken care to ensure its stone walls, concrete or wood to prevent its collapse.
MINING UNIT OPERATIONS SUBETRRNEA
The unit operations that are performed during the extraction of the mineral are: boot, load, maintenance, transportation and unloading. Next is a brief description of each.