Four "mine repair" magic weapon! Three "National Mine Park" cases!

Mineral resources are very important natural resources, which is not only the indispensable material basis for the survival of human society, but also the resource guarantee for the sustainable development of economic society. China is one of the few countries with complete mineral resources in the world. With the development of economy and society, China has become a big country in the production and consumption of mineral products, and the output and consumption of many kinds of mineral products rank first in the world. However, in the process of exploitation and utilization of mineral resources, serious ecological damage has been caused, which has become an important factor restricting the long-term development of China's economy and society.

How to fully reflect the concept of green development, respect nature, comply with nature, protect nature, find gold and silver mountains, and retain clear water and green mountains in the investigation and ecological restoration, is the proposition of The Times that geologists and mining workers must solve.

In the process of mining, a large amount of land has become abandoned land due to the loss of utilization value, such as open-pit stope, waste rock yard, tailings reservoir, subsidence area, etc. Mine restoration is to repair the pollution of abandoned mining land and realize the reuse of land resources. The natural restoration of abandoned mining land takes about 100 years. Therefore, it is necessary to restore the ecological environment of mine wasteland artificially. It can be said that mine ecological restoration is not only one of the important steps to protect the environment, but also one of the important means to explore its value.

Because of the difference of mineral resources, the treatment key of abandoned mines is also different. Generally speaking, mining wastelands are divided into four categories: waste rock deposits formed by stripping of topsoil, mined rock fragments and low-grade ore deposits; Mining wasteland formed in the goaf and subsidence areas left after the mining of ore bodies is completed; Tailings abandoned land formed by the accumulation of tailings after the ore is mined and the concentrate is selected; Land occupied and abandoned by mining operations, mechanical facilities, ore auxiliary buildings and road traffic. In the continuous practice and exploration, gradually formed the mine ecological restoration of four magic weapons:

1. Turn "danger" into "safety", and slope governance wears green clothes

The main work of slope treatment is to stabilize the slope. The task of this process is to remove dangerous rocks, reduce the slope and cut the slope, form the horizontal step of the cliff without steps as far as possible, and reduce the slope slope below the safety Angle to eliminate the hidden danger of collapse. Subsequently, the slope that has been treated should be greened to further maintain stability.

2. Turn "waste" into treasure, and the tailings show new vitality

Tailings resource is a kind of resource with the largest quantity and the highest comprehensive utilization value among metal and non-metal mine wastes. The disposal of tailings not only needs to occupy a large amount of land, causing great harm to the surrounding ecological environment, but also invests in treatment and maintenance costs. The comprehensive recovery and utilization of tailings resources can not only make full use of mineral resources, expand the scope of utilization of mineral resources, extend the service life of the mine, but also an important means to protect the ecology, but also save a lot of land and capital, and realize the effective unity of resources, economic, social and environmental benefits.

In the aspect of concrete treatment, the tailings that occupy a lot of land are redeveloped to improve the comprehensive utilization rate of tailings; To develop the tailings with large consumption, less investment and sales, in order to realize the resource utilization and commercialization of scale management and multi-variety development, so that it can turn waste into treasure and truly become a part of economic commodities; The waste water in the tailings dam is treated to meet the national standard, and the flotation waste water is fully reused and zero discharged after moderate purification. In addition, for mines with untreated goaf, abandoned roadway and chamber, the underground goaf is used to discharge tailings.

3. Turn "pollution" into good and speed up the ecological reconstruction of mines

The key to ecological damage caused by mining is land degradation, that is, the deterioration of physical and chemical properties of soil in abandoned land, the loss of nutrients and the increase of toxic and harmful substances in soil. Therefore, soil improvement is one of the most important links in the ecological restoration of mine abandoned land. The measures that can be taken include: first, the measures of taking soil in different places: on the premise of not destroying the soil in different places, take an appropriate amount of soil, move it to the severely damaged part of the mine, plant plants on the soil, and repair the damaged soil through the role of plants; The second is the abandoned land transformation measures: before the topsoil transformation, try to inject mud to wrap the waste residue, and then lay a layer of clay compacts to create an artificial water barrier, reduce the infiltration of surface water, and prevent the release of highly toxic elements in the waste residue; The third is the soil fertilizer improvement measures: adding effective substances to improve the physical and chemical properties of the soil, thereby shortening the vegetation succession process and speeding up the ecological reconstruction of the mine abandoned land.

4. Turn "poverty" into "spring", and plant restoration shows a new face

Phytoremediation is a common technique for mine ecological restoration. This technology can stabilize the contaminated soil and prevent the secondary pollution of groundwater while repairing the contaminated soil, which does not damage the soil structure and reduces the repair cost, so it has become a research hotspot of heavy metal pollution remediation technology. Generally, mine abandoned land is extremely barren, poor soil structure and other harsh environment, heavy metal tolerant plants can not only adapt to this land, but also tolerate heavy metal toxicity, and even some tolerant plants can enrich high concentrations of heavy metals, so they are widely used in the restoration of heavy metal polluted land. At the same time, considering the ecological problems that may be brought about by introduction and the adaptability of native plants to local climatic conditions, it is necessary to screen heavy metal-tolerant plants based on local conditions.

The National Mine Park case

1. Huangshi National Mining Park, Hubei Province

Huangshi National Mining Park is located in the Tieshan District of Huangshi City, Hubei Province. The core landscape of Huangshi National Mining Park is the "Mining and Metallurgical Grand Canyon", which is shaped like a huge inverted gourd. It is 2200 meters long from east to west, 550 meters wide from north to south, with a maximum drop of 444 meters and an opening area of 1.08 million square meters.

2. Dongtian National Mine Park, Changyu, Wenling, Zhejiang

Dongtian National Mining Park in Changyu, Wenling, Zhejiang Province, has been mining stone for more than 1,500 years since the Southern and Northern Dynasties, forming 28 cave groups and 1314 caves in Changyu, which is the world's largest man-made cave scenic spot. Its landscape features are set of adit, adit connection, adit overlapping, adit water, adit sky, adit painting, with outstanding stone adit structure appreciation value and artificial unintentional aesthetic value.

Third, Xinjiang rich Keketuohai Rare Metal National Mine Park

Xinjiang Fuyun Keketuohai Rare Metal National Mine Park is located in Fuyun County, the southern foot of the Altai Mountains. Keketuohai rare metal deposit has a mining history of 70 years, has the reputation of "natural mineral exhibition hall", and is a classic example of the study of pegmatitic rare metal deposit in the world. It is known as the "No. 3 vein" of the world's fourth largest open pit mine, which contains 84 kinds of minerals such as tantalum, niobium, potassium and silicon. Rare metal mining relics constitute the core landscape of the mine park.