Treatment and utilization of mine solid waste paper 1
Abstract: With the rapid development of China's metallurgical industry, the intensity of mining is gradually increasing. In the process of mining, the amount of mine solid waste is also increasing.
Keywords: mine solid waste treatment and utilization
1 analysis of the present situation of mine solid waste in China
China is rich in mineral resources, with a large amount of mineral resources and many mining enterprises. In the process of mining, due to unreasonable mining and utilization, a large number of mine solid wastes have been produced over time. There are four main sources of mine solid waste: waste rock, tailings, fly ash and coal gangue, of which waste rock is the most.
Due to the large scale of mining in China, there are many small and medium-sized mining enterprises, and the total amount of mine solid waste is on the rise. Take Shanxi and other major coal provinces as an example, the solid waste of mines in a province can reach hundreds of millions or even billions of tons.
Unreasonable exploitation of mineral resources produces a large number of mine solid wastes, which not only wastes mineral resources, but also has a great impact on the ecological environment. Mine solid waste accumulates on the land surface, destroying the land, natural landscape and surface vegetation, aggravating soil erosion and causing serious damage to the ecological environment.
In addition, the random stacking of tailings and waste rocks may cause river siltation and water pollution. Mine solid waste contains a variety of heavy metals and chemicals, which causes serious pollution to surface water and groundwater. At the same time, in dry weather, solid waste may produce a lot of dust. Pollution to the atmosphere.
2 Mine solid waste treatment
2. 1 stacking processing
This treatment method is to directly pile the mine solid waste to the designated place. The designated place must meet the following conditions: First, it is necessary to pay attention not to cause groundwater pollution and prevent the groundwater quality from declining due to the stacking of solid waste in mines.
Second, be careful not to cause surface water pollution to prevent surface water pollution or sediment aggravation caused by weathering and leaching of mine solid waste. Third, we should pay attention to reducing the air pollution caused by mine solid waste and reducing the degree of wind erosion. Fourth, we should pay attention to the safety of mine solid waste stacking to prevent a large number of mine solid waste stacking from causing disasters such as earthquakes or floods.
When choosing a stacking site, the hydrological conditions, topography and wind direction of the site should be considered comprehensively. At the same time, in the choice of tailings stacking, due to the particularity of tailings, the stacking requirements are high, and the strength of tailings dam foundation materials is very high and impermeable. Two ways can be adopted, one is the treatment of coarse and fine tailings residue, and the other is the semi-dry heap of tailings.
After the solid waste in mines is stacked, it is necessary to cover the stacking surface with mud or stones, or plant plants, or chemically treat the covered toilet surface, so as to keep the stability of stacked materials, reduce secondary pollution sources and prevent more serious damage to water resources and atmospheric environment.
Pollution.
2.2 Reclamation treatment
At present, reclamation is an important method of mine solid waste treatment, which combines mine mining with land reclamation. In the process of mining, the surface soil of mineral resources can be stored after surface mining. After the completion of the mine construction, the solid waste of the mine can be filled into the mining area, and then the topsoil can be laid and plants can be planted to complete the process of reclamation and planting. The reclaimed land can be used for the construction of public infrastructure and the production of agriculture, forestry, animal husbandry and fishery.
2.3 Landfill treatment
This method is mainly to prevent the formation of a large number of mined-out areas after the exploitation of mineral resources. Generally, cement is mixed into tailings, and the goaf is filled by cemented filling method to prevent casualties caused by mine collapse during mining. When burying toxic and harmful mine solid waste, the protection of groundwater and surface water should be fully considered to prevent pollution and destruction of water resources, and the site environment should be comprehensively considered to ensure landfill safety.
3 the utilization of mine solid waste
The treatment of mine solid waste is to reduce the environmental pollution and ecological damage caused by mining. With the concept of circular economy and sustainable development put forward, the treatment of mine solid waste should make full use of modern advanced science and technology to realize the recycling of waste and the recycling and sustainable development of resources.
In the process of mining, we should not only make full use of modern mining technology and advanced mining equipment to improve the efficiency of mining operations and reduce the waste of mineral resources. Strengthen mining management, especially the strict management of mining links of small and medium-sized mining enterprises, to prevent the increase of mine solid waste caused by human factors.
At the same time, in the process of mining, it is necessary to strengthen the exploration and development design of mineral resources, and use mine solid waste as the filling material of goaf to realize the recycling of resources and reduce the damage of mine solid waste to the ecological environment.
3. 1 Recovering useful elements from wastes
As mentioned above, mine solid waste contains a lot of heavy metal elements, such as lead, zinc and silver in lead-zinc tailings, copper, zinc and associated elements in tin tailings. If these useful elements can be recovered in the treatment of mine solid waste, it can not only reduce the damage to the environment, but also be used in production practice to promote the progress of social production.
In the recovery process, electrolytic air flotation, solvent extraction, heavy magnetic levitation, electrode recovery and other methods can be used. In recent years, microbial leaching technology has been developing continuously, and its application scope in actual production practice has become wider and wider.
3.2 Manufacturing building materials
Mine solid waste can be used to make building materials. There are three main types: first, it can be used to make cement and silicate building materials. Because mine solid waste contains a lot of elements such as aluminum and silicon, it can be extracted to make silicate building materials. The second is glass.
For example, quartz vein gold mines and tungsten mines contain a lot of quartz, carbonate mines contain a lot of fluorite, calcite and dolomite, and granite tailings can be used as raw materials and ingredients for glass production. The third is the manufacture of glass ceramics. Glass-ceramics, also known as glass ceramics, is a special kind of glass formed by controlling crystallization on the basis of basic glass.
Made of recyclable metal tailings, glass-ceramics can be used for building partition walls, with good heat resistance and energy saving.
The fourth is casting stone. Mine solid waste contains a lot of coal gangue and waste rock. If there are granite, dolomite, fluorite, basalt and limestone in mine solid waste, they can all be used as ideal raw materials for casting stone. In modern industrial production, cast stone is a very important raw material, which can replace alloy materials, steel and other raw materials under certain conditions and has strong production applicability.
4 conclusion
The exploitation of mineral resources is a major event related to the national economy and people's livelihood. In the process of mining mineral resources, advanced mining technology and equipment should be adopted to improve mining efficiency, control the production of mine solid waste and reduce the damage to the ecological environment.
At present, there are three main treatment methods of mine solid waste: stacking, reclamation and landfill. With the development of circular economy and the concept of sustainable development, the recycling of mine solid waste has become the only way for sustainable economic development. The effective recovery of mine solid waste can not only provide raw materials for social production, but also reduce the damage to the ecological environment and promote the sustainable development of the economy.
refer to
[1] Sun, Deng Junping. Treatment and Reuse of Mine Solid Waste [J]. Value Engineering, 20 10/0,29 (12).
Wang Jinhua, Li Fuping. GIS-based solid waste management system for mining enterprises [J]. Metal Mine, 20 12(6).
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Treatment and utilization of mine solid waste II
Abstract: The rapid development of China's metallurgical industry has intensified the development of mines and produced a large number of mine solid wastes. Mine solid waste pollution includes a large number of waste rocks produced by stripping and pit mining in open pit mines, tailings produced by mineral processing and slag produced by smelting.
[Keywords:] slag solid waste treatment and utilization
1. Introduction
China is rich in mineral resources, with a large total. In the process of mining, due to unreasonable mining and utilization, a large number of mine solid wastes have been produced over time. The main sources of mine solid waste are waste rock, tailings and fly ash.
Several mining areas under a certain group company mainly produce nonmetallic minerals, belonging to small and medium-sized mining enterprises. Due to the large-scale development in recent years, the total amount of mine solid waste is on the rise, resulting in a large number of mine solid waste, which not only wastes mineral resources, but also has a great impact on the ecological environment.
Mine solid waste can generally be divided into two categories: one is tailings, that is, solid waste discharged during mineral processing, and its storage place is called tailings pond; The other kind is stripped waste rock, that is, geotechnical materials stripped in the process of mining ore. The place where waste rocks are piled up is called a dump.
Mine solid waste accumulates on the land surface, destroying the land, natural landscape and surface vegetation, aggravating soil erosion and causing serious damage to the ecological environment. In addition, due to the random stacking of tailings and waste rocks, solid waste may produce a lot of dust in dry weather. Pollution to the atmosphere.
2. Harm of solid waste
2. 1 solid waste directly causes environmental pollution and destroys the ecological environment.
The mines under the company transport the ore mined underground to the open air. After primary selection, it is directly or secondarily processed into small particles and transported to the processing plant. Because this mode of production belongs to extensive processing production, solid waste piled up outside the open-air factory building will be produced during the processing production. Solid waste is not effectively shielded, which will directly pollute the environment of the factory. In particular, tailings ponds need to occupy a lot of land.
According to incomplete statistics, the tailings pond in China covers an area of over130,000 mu. With the closure of old tailings ponds, the number of new tailings ponds is increasing, which is bound to occupy more land.
The solid waste site covers such a large area, although it is mostly hillside, but the damage to vegetation is still very serious. Not only that, the storage yard occupies land, but also destroys landforms, resulting in soil erosion and degradation of soil and water conservation functions. All these may make the ecological environment unbalanced.
2.2 Solid waste stockpiling causes serious waste of mineral resources.
In particular, the ore is low in grade, mostly multi-component, fine in particle size, backward in mineral processing equipment and low in management level. Therefore, the waste of useful resources in solid waste is considerable.
2.3 There are potential safety hazards in solid waste storage.
Solid waste is prone to flow, collapse and landslide, and once an accident occurs, the loss is quite huge.
3. Mine solid waste disposal
3. 1 solid waste treatment target
The goal of solid waste treatment is harmlessness, reduction and resource utilization. According to the characteristics of the company, the nonmetallic minerals produced and processed by the company do not contain harmful impurities, so the goal of the company's treatment is to reduce and recycle.
3.2 treatment methods
3.2. 1 stacking processing
This treatment method is to directly pile the mine solid waste to the designated place. Tailings can be stacked by semi-dry method. After the mine solid waste is stacked, keep the pile stable, reduce the secondary pollution sources, and prevent the pollution of water resources and atmospheric environment.
3.2. 1 landfill treatment
This method is mainly to prevent the formation of a large number of mined-out areas after the exploitation of mineral resources.
The above two methods are the treatment of solid waste, and the more optimized method is the utilization of mine solid waste. Improve efficiency and realize sustainable development.
4. Utilization of mine solid waste
The purpose of mine solid waste treatment is to reduce environmental pollution and ecological damage caused by mining, but according to the concept of sustainable development, reasonable and effective technologies should be adopted to directly treat and utilize mine solid waste.
In view of the particularity of this enterprise, we mainly take the following aspects to make use of it.
4. 1 Making building materials. According to the characteristics of the mine, the tailings can be made into silicate building materials after extraction.
4.2 Soil improver. Due to unreasonable fertilization and irrigation, soil hardening, soil fertility decline and heavy metal content exceeding its background value caused by increased yield also caused serious degradation of high-quality soil. Because tailings contain elements to improve soil, they can be used as one of the raw materials of soil improver.
4.3 Trace element fertilizer.
4.4 Establishment of ecological zones. Tailings discharge area can build some land and constructed wetlands, plant plants, optimize the surrounding environment and restore the ecosystem.
5. There is a problem
Generally speaking, the comprehensive utilization and harmless treatment of mine solid waste started late. Although many mining enterprises and scientific research institutions have done a lot of work and achieved certain results, the overall development is not slow and there are still some problems. Mainly includes:
5. 1 Enterprise's enthusiasm is not high
Although the government has formulated preferential policies for tax reduction and exemption for comprehensive utilization of resources, it has not specifically formulated policies to encourage the utilization of tailings and waste rocks, which has failed to fully mobilize the enthusiasm of enterprises to carry out comprehensive recovery and utilization of solid waste.
5.2 The application field of solid waste is narrow.
At present, the comprehensive utilization of mine solid waste in China is mostly limited to the recovery of useful components and the production of building materials, with few high value-added products and no market competitiveness. This is another factor that leads to the low enthusiasm of enterprises.
Step 6 recommend
6. 1 Mining enterprises advocate cleaner production
The project is mainly supported by the government and guided by various policies and technical assistance. Strive to realize the reduction, recycling and harmlessness of solid waste, promote clean production, and eliminate solid waste as much as possible in the production process.
6.2 Encourage the development of solid waste treatment industry.
Encourage enterprises to establish a circular economy production system, establish a solid waste management and operation mechanism in line with the market economy, move towards openness and cooperation, realize enterprise management, take the road of industrialization, develop China's mine economy and improve China's mine environment.
7. Conclusion
To solve this problem of mine solid waste, national and local governments, mining enterprises and scientific research departments need to jointly tackle key problems and develop together. The production of mine solid waste is not only determined by the characteristics of China's mineral resources, but also the historical accumulation of China's mining development for thousands of years, and it is also the result of unreasonable utilization of mineral resources. Mine waste contains a large number of unused precious mineral resources, but it is difficult to develop, with high technology content and large capital demand, and it needs the joint efforts of all parties to embark on the road of sustainable development.
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Discussion on the treatment and utilization of mine solid waste: a guide to scientific and technological innovation; 2013,02.
[2] Comprehensive utilization of mine solid waste to improve enterprise benefits; Proceedings of the 2nd1Mining Academic Exchange Conference of the Metal (Metallurgical) Society of roes Yueluchuan, Hebei and Liaoning Provinces: 490.
[3] Treatment and disposal of mine solid waste; Protection and utilization of minerals; June 5438 +2003 10, issue 5.
[4] Report on the development of mine solid waste treatment and disposal technology; National Environmental Protection Mine Solid Waste Treatment and Disposal Engineering Technology Center.
[5] Resource utilization and disposal of mine solid waste in China; Modern mining industry; 20 12, 10, issued 10.