1.2 caving methodî—Ž
Sublevel caving is a stable and efficient manner mining, metallurgy in underground mines use proportion of 80%. In China's underground mines, since the introduction of the mining method, after decades of development and progress, its structural parameters have gradually increased from the initial 10m * 10m (segment height * route spacing). The biggest parameter adopted by China today is 20m*20m. Increasing the structural parameters of the stope, increasing the amount of collapse, and adopting an electric, fully hydraulic large-scale trackless mining machine to reduce the amount of mining work, in order to improve the labor productivity of all employees and reduce the mining cost, this method will be in the next few years. Direction of development.
1.3 Filling mining lawî—Ž
The filling mining method has the characteristics of achieving large mechanization, especially in the areas of mining, support and mining. Among the filling techniques, the fastest non-cement filling method is upgraded from the graded tailings cemented to the high tailings high-concentration cemented filling, to today's zero dewatering without shortening the full tailings cement filling. In the mining technology, the filling technology has made great progress from increasing the height of the stratified section to the large hole and falling mine. The structural parameters of the stope are gradually improved, and the panel is completely filled with no artificial full mechanized filling; Microcomputer remote control is fully automated; the new tailings paste paste pump is used to fill the new method, which also enables the mining technology to achieve efficient mining.
2 Problems in mining of metal mines î—Ž (1) Uneven distribution of resources. China's mineral resources are rich in poor ore, with few rich minerals, large and extra large mines, and scarce mineral resources. Moreover, in order to obtain better economic benefits, some mines have abandoned poverty and caused a large amount of waste of mineral resources.
(2) The development of mining technology is uneven. China has a land area of ​​9.6 million square kilometers, which has caused a large gap in economic levels across the country, as well as the level of mining development. For example, in coastal economically developed areas, mining and related science and technology have already reached the international advanced level. In underdeveloped areas such as the west, mining and related technologies are very backward, and there are not enough advanced equipment, which leads to the exploitation of mineral resources. The main reason for the low rate. 
î—¥ (3) The comprehensive utilization rate of resources and the low rate of resource recovery. Most of the non-ferrous mines are metal mines, and related practitioners have begun to pay attention to how to recycle effective minerals. Foreign countries have reached a leading level in the comprehensive recycling technology of polymetallics, and China has almost no comparable in these technologies to developed countries. China's mineral recovery rate is around 30%; and developed countries have reached 50%, which shows that China's technology level is still far from the developed countries.
(4) The environment is seriously damaged. Underground mining induces ground collapse, damage to topographical landscapes, destruction of land resources, and damage to groundwater resources. Mineral mining directly leads to deterioration of the geological environment of the mine, and the pressure on the environmental capacity is doubled. The environmental problems in the mine are more prominent, and it is impossible to meet the latest economic and social development requirements.
3 Development trend of metal mining technologyî—’î—
(1) Deep well mining. Shallow resources have been nearly exhausted due to unregulated mining in recent years. China has begun to gradually exploit resources deep into the underground. It is estimated that within 10~20 years, China's mines will begin to enter the depth of 1000~2000m. In fact, as early as the 1960s and 1970s, the Chinese government began to allow a small number of mines to start deep mining. At that time, some new mines were also deep in mining depth. î—Ž
(2) Mining technology for large and deep open pit mines. Nowadays, some mines in China have entered large-scale deep-sea open pit mining. With the increase of mining depth, the size of the working space in the stope is gradually reduced, the difficulty of carrying out transportation is increasing, the mining intensity is reduced, the transportation interval is getting larger and larger, the heavy truck is running uphill and the interval is long, the machine efficiency is reduced, and the production capacity is reduced. . Nowadays, China has formed a relatively mature and systematic research method, which has formed a series of large-scale open-pit mining technology and its associated machine technology, remote-controlled blasting technology, and some necessary disaster prevention and control and environmental regulation. Related technology.
(3) Residing mining technology outside the open pit mine. Many large-scale metallurgical open pit mines in China are gradually entering the late stage of mining, but due to technical and economic conditions, a large amount of mineral resources are left outside the open-pit mine. If it is to expand the situation, it will cause deterioration of the economic indicators of the mine, and the acquisition of a large amount of land will destroy the ecological environment. In order to reduce the loss of the characteristics of the altered rock type ore in China, the gray system is adopted to select the mining method, and the roof of the stope under complicated conditions is remotely controlled; the combination of acoustic emission and ground pressure and displacement monitoring is applied. Ensure the protection and rational use of mineral resources.
(4) Mining technology for complicated water-rich deposits. In the process of mining rich water deposits, the monitoring and forecasting remote sensing technology can be used to grasp the law of groundwater gentle pressure and sudden change of the groundwater, and to make the water inrush mechanism and preventive measures of the complicated water deposits to ensure the safety first in the construction process. The specific measures can adopt the three-field coupling decomposition technology of rock formation deformation-stress-seepage in the underground to ensure the feasibility of the construction process and construction method.
(5) Mining techniques for complex and difficult underground mining ore bodies. Long-term mining of underground metal mines in China, due to the constraints of technical level and the effects of chaos and excavation at that time, there is still a large amount of ore resources remaining in the mining area. These residual ore resources are complicated in mining technology, and the stable conditions are poor. The large number of empty areas and pillars left behind are too late for useful disposal. The main difficulties in accepting and accepting these residual resources are the detection technology of residual resources in complex airspace, the large-parameter large-scale integrated caving technology, the re-engineering technology of residual resource mining, the receiving technology of the mine column under the complicated filling body and the stable recovery monitoring of the complicated residual ore body. Early warning and other technologies. The solution of these technical problems will surely play an important role in improving the utilization of mineral resources and promoting the upgrading of mining technology in China.
î—Ž (6) Unmanned mining, automatic mining, digital mines. With the development of unmanned mining technology, visualization technology, 3S (RS, GPS, GIS) technology and virtual reality technology, the system is more digitally used, integrating mines and other related information, computing technology and industrial remote control technology. Planned mining plan, rational setting of machine layout resources, development of remote control technology and its supporting system have become a comprehensive, dynamic and accurate grasp of the stock and transformation of China's mineral resources, and scientific and rational development and utilization of resources and mineral resources. sustainable development.
î—Ž (7) No waste mining. Non-waste mining is closely related to sustainable development. If we do not attach importance to non-waste mining, we will not pay attention to the protection of the environment and resources, and the premature exploitation of resources will definitely cause huge losses to the mines and the national economy. Therefore, we must use the development vision to plan mining and ensure the sustainable development of the local economy.
4 Conclusion
This article discusses the achievements of China's mining technology in recent years, as well as some problems encountered during the same period. From the perspective of mining equipment, systems, digital management and operation, the future development direction of China's mining technology is discussed.
references:
[1] Editorial Board of the Mining Manual. Mining Manual [M]. Beijing: Metallurgical Industry Press, 1 9 9 9 . î—’ î—
[2] Chen Tianlin. The status quo and development trend of China's mining technology [J]. Case Study, 2 0 1 1 , 1 8 ( 7 ): 5 0 4 . î—’ î—
[3] Hou Wanrong, et al. The current situation and countermeasures of comprehensive utilization of mineral resources in China [J]. Mining Technology, 2 0 0 6 , 6 ( 3 ) : 6 3 ~ 6 6 . î—’ î—
Article source: "Abstracts of Nonferrous Metals", 2015, 30 (1)
Author: Zhu and, from the sky map, Liu Haitao, Li Jiahao; Hunan-based anchor class Star City District Xiang Yang West, Hunan class end 417 009
Copyright:
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