Food Vitamin B3 Niacin,Drink Additive Vitamin B3-Food,Lipstick Additive Vitamin B3-Food,Rice Additive Vitamin B3-Food SICHUAN YINHE CHEMICAL CO.,LTD , https://www.sichuanyhcc.com
In order to change the deterioration of the ecological environment of the mine, countries around the world have carried out the restoration of the ecological environment. For example, in the work of Restoration (Reclamation, Rehabilitation) in Europe and the United States, the National Academy of Sciences defined three terms in 1974 and was adopted by many countries: Restoration refers to the state of existence before restoration to destruction. This includes re-repairing the damaged topography, restoring the surface water and groundwater before the destruction, and re-establishing the original plant and animal community, which can be translated as “recoveryâ€. Reclamation refers to the restoration of the damaged area to the state before the destruction, mainly including the restoration of the terrain before the destruction, and the restoration of the plant and animal communities to the level before the destruction. It should be translated as “recoveryâ€, however, China has become accustomed to translate it as "rehabilitation." Rehabilitation is the restoration of the destroyed site to the form and productivity consistent with the plan developed prior to the destruction, which can be translated as “reconstructionâ€.
The American Society for Ecological Reconstruction defined ecological reconstruction (recovery) in 1994 as restoring the ecosystems destroyed by humans into local ecosystems with biodiversity and dynamic balance. In China, the term “land reclamation†was first called “land-building and land-recoveryâ€, “Futianâ€, “垦å¤â€, “re-cultivationâ€, “rehabilitationâ€, “integrated governanceâ€, etc. until 1988 11 The State Council promulgated the "Regulations on Land Reclamation" and the term "land reclamation" was confirmed by China. The definition of land reclamation in the Land Reclamation Regulations is: land reclamation refers to the remediation measures taken to restore the land damaged by the excavation, collapse, and occupation during the production and construction process. Activity for utilization status. According to the current "regulations" and actual conditions in China, the purpose of "land reclamation" refers to taking engineering measures to restore the damaged land (man-made damage or natural damage), returning to the available state of the land, and making the production and construction healthy. At the same time of development, land resources and the environment can be protected and continuously utilized.
Regardless of the terms Restoration, Reclamation, Rehabilitation, or land reclamation, land consolidation, ecological reconstruction, ecological restoration, etc., these terms have in common the restoration of disturbed ecosystems. However, the direct feeling of using these terms is to carry out ecological reconstruction (recovery) of the land damaged by the mine. It seems that the land and water bodies polluted by the mine are not included. The actual situation is also the same. The ecological restoration work is more important. Only the water bodies and land polluted by the mines have reached a very serious level before taking measures, and most of them are taking some compensation measures. Some people think that the goal of land reclamation is not only to restore the use value of land, but also to restore the function of its ecological environment. Some people think that land reclamation has developed to the stage of ecological reconstruction, and it is necessary to replace "rehabilitation" with "ecological reconstruction." The term “ecological restoration†is often used for the ecological management of polluted water bodies and land. Therefore, from the perspective of the overall consideration of ecosystems, from the perspective of the impact of mine development on ecosystems, from the perspective of development, the use of “ecological restoration†In line with reality, emphasizing ecology, not just emphasizing land, emphasizing restoration, not just reclamation.
China has put forward some indicators for the reclaiming of mine land. The “Technical Policy for Mine Ecological Environment Protection and Pollution Prevention and Control†requires that the reclamation rate of newly built mines by 2010 should be no less than 75%. However, how to conduct calculations and how to conduct assessments, the current standards and methods need further study. For example, if a mine uses full tailings to fill, the waste rock does not go out of the pit mining production technology, there is no waste rock yard and tailings pond. The mine covers an area of ​​industrial plants. How to calculate the mine reclamation rate for such mines? ? The land reclamation rate indicator alone may have the following shortcomings:
1. The conditions of each mine are different, and there is sometimes no comparability between mines.
2. The ecological restoration of open pits, waste rock yards, tailings ponds, etc. has obvious stages.
3. In order to meet the national requirements for land reclamation rate indicators, design departments, management departments, and mining enterprises can sometimes only compile. To this end, a scientific mine ecological restoration assessment index system should be established to guide the ecological restoration of mines.
   I. Characteristics of the impact of mine development on the ecological environment
(1) Basic characteristics of the impact of mine development on the ecological environment
The impact of mine development on the ecological environment includes direct and indirect effects. The direct impact is mainly the impact of direct land occupation on the ecological environment, including open pits, waste rock yards, tailings ponds, industrial sites, office and living areas, roads, pipelines, underground goafs, groundwater drop funnels; It is mainly secondary damage and pollution induced by mine development, mainly land collapse, contaminated groundwater, contaminated surface water bodies, and contaminated land. The main characteristics of this direct and indirect impact of mine development are shown in Table 1.
Table 1 Main characteristics of the ecological environment impact of mine development
Affected body
direct impact
Open pit
The hillside open pit mine will form a stepped topography, and the open pit mine will form a stepped deep pit with steep slope and bare base rock.
Waste stone field
The valley type and flat type waste rock yard (dumping ground and dumping field) will form a stacking mountain, which will form a step on one or more sides. The step slope is steep and the particle size is scattered. Most of them are mixed with rock and soil.
Tailings pond
The valley type and flat type tailings reservoir will form a stacking mountain, which forms a step shape on one or more sides. The step slope is steep, the grain size is fine, and it is susceptible to water erosion and wind erosion.
Underground gob
Underground underground areas such as underground roadways, diverticulums, and mining sites formed by underground mining.
groundwater
Landing funnel
Groundwater pumping is carried out to ensure safe production of the mine, and the resulting groundwater falls into the funnel area.
Road pipeline
The area is strip-shaped. The disturbance is relatively minor.
Industrial site
The industrial facilities selected for production are mainly constructed and constructed.
Office
Living Area
The mine office living area is mainly for building and building.
Affected body
Indirect effects
Collapse
Due to underground mining, it takes a long time to stabilize, and generally does not change the stratigraphic sequence, which is basin-shaped, funnel-shaped, and crack-like.
Infected
Water body, land
Waste water containing heavy metals, acid, alkali and other contaminants, causing dust, once contaminated, difficult to repair contaminated mine formed surrounding water and land.
(2) Temporal and spatial characteristics of the impact of mine development on the ecological environment
The impact of mine development on the ecological environment has obvious characteristics of time and space changes. With the passage of time, the impact of mine development on the ecological environment is gradually formed, and it changes dynamically during the whole production period of the mine. The most obvious are open pits, waste quarry (discharge yards, dumping sites), tailings ponds, underground goafs, subsided areas, groundwater drop funnels, the scope of influence, and the degree of influence are gradually expanded to surface water and groundwater. The pollution of the land is also gradually formed.
(III) Analysis of main restrictive factors of mine ecological restoration
There are many constraints on the ecological restoration of mines, such as topography, soil physical and chemical bio-characteristics, local climatic conditions, hydrological conditions, topsoil conditions, and potential pollution. The following is a brief analysis of typical destructive sites in mines, mainly analyzing open pits, waste quarries (discharge sites, dumping sites), tailings ponds, subsidence sites, contaminated surface water, and contaminated land.
The constraints of ecological restoration in open pit are mainly stepped terrain and exposed bedrock. In order to reduce the amount of peeling, in the case of ensuring production safety, open pit mines generally use steep mining as much as possible. The slope of the open-air step is large, and some slopes reach 70° or more. Therefore, it is very difficult to establish vegetation on the slope of the open pit. Basically impossible. The open pit platform is generally bare base rock, and it is very difficult to establish vegetation directly on it. It is often necessary to cover the soil or the hole-like land preparation. Rehabilitation of open pits, especially deep pits, is often not the first choice. If it can be used as a secondary development site for mining industry tourism site development, solid waste disposal sites, and restoration to water surface, it can be given priority. If vegetation is to be established, its ecological restoration rate is generally low, generally reaching 50%.
Waste rock yard (dumping ground, drainage field, meteorite mountain), the surrounding rock waste rock generated in the mining process that cannot be utilized in the current economic and technical conditions, different habits in different mines and different minerals The title is collectively referred to herein as the waste quarry. The constraints of ecological restoration of waste rock sites are mainly stepped terrain, extremely unevenness of waste rock mass, and potential pollutants. The slope angle of the waste rock yard is often the natural accumulation angle of the waste rock, and the slope is steep. The waste rock mass of the waste rock field is extremely uneven, and the large diameter can reach more than 1m, even larger, and the small size is millimeter micron. In the case of vegetation, it is very difficult to cover the soil and cover the soil in a comprehensive manner; some waste rock waste rock, especially the waste stone with high sulfur content and heavy metal elements, is easily weathered and oxidized, generating potential acid pollution and heavy metals. pollution, such as iron ore Nanshan acidic waste rock, mine waste rock DEXING Cu and the like. The ecological restoration of waste rock yards is mainly based on the establishment of vegetation. Generally, the whole land is covered with soil, the hole is grounded, and the soil inside the hole is used. If there are potential pollutants, it is necessary to take measures such as blocking and other pollution prevention measures. If vegetation is established, its ecological restoration rate can reach more than 85%.
The constraints of ecological restoration of tailings ponds are mainly fine-grained tailings, potential pollutants, and stepped topography. The tailings pond tailings are fine in size, extremely windy and water-erodible. In order to prevent wind erosion and water erosion, the surface is covered with a layer of no less than 30cm of topsoil; the composition of the tailings is affected by the ore composition, and the ore containing heavy metal elements is contained in the tailings. These elements are also included, and there are residual flotation agents for the flotation tailings, which have a potential for contamination. The ecological restoration of tailings ponds is mainly based on the establishment of vegetation. Generally, it adopts comprehensive land preparation, hole-like land preparation, and empty interior soil. If there are potential pollutants, it is necessary to take measures such as blocking and other pollution prevention measures. If vegetation is established, its ecological restoration rate can reach more than 85%.
The restrictive factors of ecological restoration in subsided land are mainly the extent and extent of subsided land. The collapsed land generally does not change the soil layer structure, but the degree of collapsed land is different, and the degree of ecological restoration is different. For the funnel-shaped collapse ground, the repair is difficult, especially when the metal mine mines the steeply inclined deep ore body. If the caving method is adopted, the collapse degree is large, and the collapse is as deep as tens of meters or even hundreds of meters. Generally, safety protection is adopted. Measures are based on natural restoration. For smaller extent collapse collapse basin often carried out land consolidation, to restore arable land based, such as a lot of coal mine subsidence land is so, therefore, for the basin subsidence collapse of the ecological value of its high ecological restoration, ecological restoration The rate is higher, up to 90%.
Contaminated surface water and land, with the increase of environmental awareness, the implementation of the EIA law, the new mines generally do not cause surface water pollution under normal circumstances, but in the case of accidents may cause surface water pollution. The problem of the old mines is more serious, mainly because the old mines have potentially polluted waste rock fields, tailings reservoirs, and other untreated water, which are directly discharged to the external environment. Contaminated surface water can slowly eliminate surface water pollution as long as it adopts source control measures.
Ecological restoration of contaminated land is difficult. Polluted land is often caused by heavy metal pollution. Heavy metals cannot be decomposed and can only change its form of existence. Ecological restoration of land contaminated by heavy metals is a long process and a worldwide problem. The rate of ecological restoration of contaminated land is generally not high.
(IV) Characteristics of the whole process of mine ecological restoration
The ecological restoration work of mines must reflect the basic characteristics of the impact of mine development on the ecological environment and the characteristics of time and space changes. The ecological restoration of mines runs through the whole process of mine production. In September 2005, the State Environmental Protection Administration, the Ministry of Land and Resources and the Ministry of Health jointly issued the “Technical Policy for Mine Ecological Environment Protection and Pollution Prevention and Controlâ€. How do the technical policies affect the development and planning of mineral resources, mine infrastructure, mining, and mineral processing ? Specific requirements are put forward in consideration of ecological environmental protection, and are not repeated here.
   Second, the mine ecological restoration assessment indicators
Different development stages of the mine, different types of land occupation, different contaminated areas, ecological restoration constraints, restoration objectives and priorities are different. Therefore, the assessment index of mine ecological restoration should also be set up according to different development stages of the mine, different types of land occupation, and different contaminated areas.
After the end of the mine construction period, it is the production period, and the whole project is marked by production. For a single project marked by a single project, the service period is marked by the expiration of a single engineering service. If there are more than two waste quarries in the mine, a waste quarry will be used in the initial stage of production, and the first waste quarry will be used. The second waste quarry will be activated after the expiration of the service, and so on. The collapsed land and contaminated land of the mine are also marked by a certain range. Therefore, the ecological restoration of the mine should be assessed by a single project and site.
Open pits, waste rock yards, tailings ponds, and collapsed land have obvious characteristics of time and space changes. In the production period, only permanent slopes and platforms can be ecologically restored. Therefore, such sites can only be used for this part during the production operation period. Assessment, the entire site should be assessed after the expiration of the service period.
The collapsed land is a process of gradual collapse and gradual stabilization over time. For the collapsed land, only the stable area can be ecologically restored, and there is a hysteresis effect in time. Therefore, for the collapsed land, the relative stable area is generally ecologically restored and ecologically carried out. Repair assessment.
Industrial sites and office production areas are mainly built and constructed. The production period is assessed by the greening rate. Generally, it is 15%. After the service period expires, it depends on whether the industrial site is used for other industrial sites. For other industrial sites, The greening rate is still used for assessment. If it is dismantled, the ecological restoration rate is used for assessment.
The road pipeline area can meet the national requirements for road pipeline greening. Temporary land occupation should be carried out immediately after the completion of construction, and the ecological restoration rate should reach over 90%.
Under normal circumstances, mines generally do not pollute water bodies and land. If pollution occurs under abnormal conditions, emergency measures should be taken in accordance with the emergency plan to eliminate pollution and recover in time. According to the above analysis, starting from the whole process, according to the characteristics of ecological restoration of different sites in the mine, the evaluation index system of mine ecological restoration is proposed and constructed, as shown in Table 2.
Table 2 Assessment indicators of mine ecological restoration
Venue category
Ecological restoration rate
Construction period
After the service expires
Waste rock yard, tailings pond
Permanent platform, slope ≥75%
The entire site ≥ 85%
Open pit
Permanent platform, slope ≥50%
≥50% of the entire site
Collapse
Stable area ≥75%
Stable area ≥85%
Industrial site, office and living area
Greening rate 15% to 30%
Road pipeline area
Meet the national greening requirements for road pipelines
Temporary land occupation
Immediately after construction, ≥90%
Contaminated water body, land
Take immediate emergency measures, ≥85%
Note: The data in the table is the reference data of the general situation, which should be determined according to the actual situation of the mine.
   Third, the conclusion
From the perspective of highlighting the ecological restoration of polluted water bodies and land, this study puts forward the concept of mine ecological restoration, such as mine open pit, waste rock yard, tailings pond, collapsed land, industrial site, road pipeline, office living area, The characteristics of land, time and space changes and ecological restoration constraints of polluted water bodies and land are analyzed in detail. From the perspective of the whole process, according to the characteristics of ecological restoration of different sites in the mine, the evaluation index system of mine ecological restoration is proposed and constructed. The assessment index has strong operability and practicality, and is convenient for use by management departments, research and design departments, and mining enterprises.