Nature of surface mining and underground mining
Flow of surface mining and underground mining
- Perforation blasting: refers to drilling a directional blast hole with a certain diameter and depth in the open-pit ore rock during surface coal mining, and blasting with explosives to break and loosen the ore rock.
- Mining and loading: It is the operation of manually or mechanically loading the ore into the transportation equipment, or directly unloading it to the designated location.
- Transportation: transporting the ore and rock in the open pit to the unloading point (or beneficiation plant) and dumping site respectively, and at the same time transporting production personnel, equipment and materials to the mining site.
- Dumping: refers to the operation of stripping a large amount of topsoil and rocks covering the upper and surrounding ore bed from the open pit, and transporting it to a specially set site (such as a dumping yard or a waste rock yard) for disposal. The bulldozing field should be located as close as possible to the mining field and occupy less farmland.
- Development: refers to digging a series of shafts from the ground to reach the deposit, connecting the deposit to the ground, forming a system for pedestrians, transportation, ventilation, drainage, power supply, air supply, and water supply.
- Accurate mining: According to the predetermined plan and drawings, excavate the excavated roadway to create the necessary conditions for the cutting and backstepping of the ore block.
- Cutting: refers to the creation of free surface and free space for large-scale recovery of ore in the ore block that has been mined.
- Stoping: The process of extracting ore from ore blocks is the core of subsurface mining. Including the three main operations of mining, transportation and ground pressure management.
Method of surface mining and underground mining
- Gentle deposit (the dip angle is generally less than 12°)
- Inclined deposit
- Natural support mining method
- Artificial support mining method
- Caving mining method
Commonly used machines for surface mining and underground mining
- Hydraulic mining shovels
- Wheel loaders
- Mining crusher
- Blast hole drilling rig
- Large Mining Trucks
- Hydraulic Mining Shovels
- Large Dozers
- Electric Rope Shovels
- Rotary Drill Rigs and Rock Drills
- Motor Graders
- Large Wheel Loaders
Commonly used machine models for surface mining and underground mining
GHH LF-14 loader
The capacity of GHH LHD is between 1 and 21 tons. As an underground mining machine, the LF-14 loader has a capacity of 14 metric tons. The LF-14 loader is versatile, sturdy and reliable. Not only suitable for underground mining, but also suitable for tunnel and soft rock applications.
FUCHENG drilling jumbos FC series
WIRTGEN GROUP 220 SMi
FUCHENG Scooptram FCYJ series
Advantages of surface mining and underground mining
- The infrastructure construction period is short and the effect is quick. It usually only takes 2-4 years to build a large open-pit mine, and 3-4 months for a small mine.
- Large mining space and high labor productivity. Luyao mining can use large-scale or super-large high-efficiency machinery and equipment, which is conducive to the realization of mining mechanization, thereby greatly improving the mining intensity.
- Strip mining has low mining cost. Due to the large operation scope of Luyao Mine, it is conducive to mechanized mining and reduces mining costs.
- Less ore loss and dilution. In metal open-pit mines, the ore loss rate is generally 3%-5%, and the dilution rate is generally 5%-8%. Open-pit mining is more adaptable and flexible.
- The labor tea is good, and the production is relatively safe.
- Subsurface mining can reduced environmental impact, higher selectivity and reduced exposure to weather.
- The land area required is much less.
Disadvantages of surface mining and underground mining
- Strip mining needs large investment. Due to the large-scale machinery and equipment used in open-pit mining, the amount of infrastructure stripping is relatively large. In addition, a large number of mines requisitioned land, which often resulted in a large investment in infrastructure.
- The mine occupies a lot of land and causes great damage to the environment. The pollution caused by dust, noise, exhaust gas and other gases during work is relatively large.
- Higher cost and longer development cycle
- Low ore recovery rate
- Greater safety risks, shortage of underground labor, and possible settlement.
Disasters of surface mining and underground mining
- Frequent occurrence of geological disasters
- Occupation and destruction of large amounts of land
- Soil erosion and land desertification
- Environmental pollution
- The groundwater level drops
- Ground collapse, ground fissure
- Soil erosion