Is Mining Dangerous?
Mining hazards specifically refer to the various hazards that may occur during the mining and operation of coal and minerals. These include ground collapses, gas explosions, water flooding, spontaneous combustion, as well as inhalation of dust and various toxic gases. [1]
- The safety of mining engineering is related to the safe production of the entire coal mine. Non-compliance with safety production regulations is likely to cause hidden safety hazards and safety accidents in the production process. For a long time, a large part of safety production accidents are caused by irregular construction of mining projects. Therefore, in the construction process of mining projects, technical factors of safe production should be fully taken into consideration. For unsafe factors found during the construction process of mining projects, it must be rectified in time to ensure the safe production of coal mines. [2]
- 1. Natural geological hazards
- (1) Engineering geology is unfavorable for rock mechanics . Because the ore body of the mining area is contained in the weathered granite crust, the engineering geological problems related to mining are mainly ground stability. The thickness of the whole wind layer is large and loose. The fissures of the strong weathering layer are very developed, and the rock mass is fragmented. The instability of the mountain mass may occur during the leaching and mining, resulting in a landslide.
- (2) Analysis of hydrogeology and hydrological data. The absolute elevation of the erosion base of the mining area is 250 m, and most of the weathered crust ion-adsorbed rare earth deposits (95%
Above) It is located above the local erosion datum, and the hydrogeological conditions of the deposit are simple types. [3]
- Dangerous technical factors in the construction of shaft engineering
- The dangerous technical factors in the construction of the shaft engineering are mainly reflected in the design and construction of the yard and the radius of curvature of the electric locomotive. In the design of mining depots, there are mainly two ways of rising and falling. The single-slope rising has the advantages of small workload and saving clothes spring turnout. It is more widely used in current mining operations and helps improve Economic benefits of enterprises. However, there is a greater danger of a single-slope rise compared to a double-slope rise. There is also a turnout for fixing. The single-slope rise has a lower safety factor. In addition, the radius of curvature of the electric locomotive does not meet the specifications will also cause serious consequences. Generally, the radius of curvature of the application is 6 m. However, because the curvature of the roadway is often greater than the radius of curvature, the wire rope on the harrow machine will be worn. Once the wire rope breaks, it will cause personnel casualties. The safety factor will also be different for different curvature radii of curved wells. In addition, design errors can obstruct the view of the driver of the electric locomotive and cause transportation accidents caused by failure to observe the forward signal. Discontinuing the defense of the side and the design of the transportation defense of the main lane are the main contents in the design, and it is often easy to ignore the treatment of the curved roadway. [2]
- Dangerous technical factors in the mining process are more complicated, and targeted measures must be taken to prevent accidents. In the design of the central mining depot, try to use the two-way ramp-up method to improve the safety factor. Select a suitable radius of curvature. For example, when applying a self-adhesive electric locomotive, the radius of curvature should be kept within 12 ~ 15 m. The radius of curvature is generally 9m. In the design of the curved roadway, it is necessary to use a linear layout as much as possible when designing the lower yard, so that the driver's field of vision can be widened to better prevent safety accidents.
- In the design of the double-track safety clearance of the lower yard, the double-track clearance should be above 1.4 m to ensure the improvement of the safety factor and the smooth passage of transportation vehicles. During the development of the roadway, the design of the semi-circular arch end face must be adopted in accordance with the roadway height safety design code standard. The height of the portway must be maintained above 1.2m to ensure the efficient transportation of electric locomotives.
- The design of the cutout and the opening of the sub-slope needs to be designed along the vertical direction of the mine to the slope direction. In the design of the main slope of the steeply inclined mine, it is necessary to ensure that the slope is above 23 ° to ensure the self-sliding of the mineral, which not only helps to obtain more mineral resources but also better protects the safety of workers. In the case of inclined mining, a short-wall mining method is required to ensure that the advanced mining distance in the upper part is above the maximum mining control top distance.
- Also pay attention to the impact of groundwater on mining projects. Under natural circumstances, the dynamic effect of groundwater is very small, and it is not a significant threat. However, with the development of man-made engineering activities, the natural dynamic equilibrium conditions of groundwater are destroyed, and the pressure of moving water increases. Causes a series of serious geotechnical hazards. Most of the geotechnical engineering dangerous events caused by groundwater are caused by changes in groundwater levels and groundwater dynamic water pressure. Among them, the reason for the change of water level is more complicated. Both natural and human factors will cause the groundwater level to rise and fall. Hidden dangers will be brought to the geotechnical engineering when the lifting range reaches a certain level. The geological engineering hazards with the highest incidence currently mainly include hazards caused by rising groundwater levels, hazards caused by falling groundwater levels and hazards caused by frequent changes in groundwater levels. The change of groundwater level is of great significance to the ore source and the rock and soil. When investigating expansive rocky soil areas, it is necessary to focus on the hydrogeological conditions of the area, especially the magnitude and frequency of the change of groundwater level. [2] [5]