12. Environmental problems posed by the mining, oil and gas industry.
The mining industry includes 3 main methods of extracting minerals: mine, open-pit, borehole. Each of them has specific environmental problems.
Mine way involves the creation of transport mine workings (mine shafts, adits) to a mineral deposit and a system for mining workings (longwalls, drifts) within the deposit. Environmental problems with this method of extraction are associated with the formation of dumps from overburden (waste heaps), a decrease in the level of groundwater as a result of their pumping out of mine workings, the danger of pollution of water bodies with mine (mine) waters.
Open way It is used for the extraction of solid minerals (coal, oil shale and peat, various ores, building materials) and involves the creation of much larger open-pit mines and open-pit mines instead of relatively narrow mine workings, which became possible with the advent of powerful earth-moving equipment. Disturbance of land cover during open pit mining leads to the formation of a "lunar landscape" of open pits and dumps, formed by completely sterile rocks and subject to fluttering, erosion and leaching of soluble components, with pollution of atmospheric air, water bodies and soils of adjacent territories.
Environmental problems of mine and opencast mining of solid minerals are solved by means of reclamation - a set of works aimed at restoring the productivity and economic value of disturbed lands, as well as improving environmental conditions. Reclamation is carried out at the end of the development of a section of the field or the field as a whole and includes two stages: technical and biological. During technical reclamation, the overburden is filled with underground workings: leveling of the surfaces of open pits and dumps. During biological reclamation, artificial soils are created (based on peat and other materials), landscaping, and stocking of water bodies. If it is impossible to carry out the vertical leveling of the relief, simplified methods of reclamation are used: the creation of reservoirs in the worked out quarries, the landscaping of waste heaps.
Downhole method used mainly for the extraction of liquid and gaseous minerals: natural gases, oil, groundwater. Some types of solid minerals can also be extracted using wells: underground gasification of coal, underground leaching of ores. The downhole method, the use of which has become possible since the end of the 19th century with the development of drilling technology, creates a load on land resources that is significantly less than mine and quarry production. The environmental problems of downhole production are related to the fact that this method affects great depths, where mining and geological conditions are sharply different from the near-surface. The geochemical environment is reducing, practically oxygen-free, pressures reach hundreds of atmospheres, highly mineralized, aggressive formation waters are widespread. Wells irreversibly violate the integrity of aquicludes separating fresh aquifers from zones of slow and very slow water exchange. With a significant scale of extraction of liquid and gaseous minerals, as well as injecting water and solutions to maintain reservoir pressure, and other impacts on reservoirs, there is a redistribution of pressures, temperatures, geochemical parameters, directions and rates of groundwater circulation. External manifestations of technogenically caused changes in the subsoil are the activation of geodynamic processes, including with the intensification of seismicity, changes in water abundance, regime and hydrochemical characteristics of aquifers, incl. leading to groundwater pollution.
In case of emergency leaks of oil, reservoir waters, process fluids, atmospheric air, soil and surface water are polluted, and damage to the vegetation cover and fauna is caused. Massive pollution of the atmosphere, surface waters and soils occurs during accidents leading to gushing oil and gas emissions. The likelihood of accidental leaks increases with the development of corrosion and wear and tear of equipment in contact with corrosive liquids. To reduce accidents, the pipeline network is reduced by concentrating a number of wells on one site (cluster), pipes with an internal anti-corrosion coating are used. Permanent sources of atmospheric pollution associated with the production and transportation of oil and gas are gas flares, oil treatment plants, gas compressor stations, and technological transport. Utilization of associated gas as fuel or chemical raw material is not always possible, because it may contain a significant admixture of non-flammable components (nitrogen, carbon dioxide).
Subsoil protection during well production includes complexes of measures developed on the basis of geoecological studies. They include: regulation of the load on the elements of the tectonic structure in order to prevent activation of faults, isolation of aquifers by cementation of the annulus of wells and elimination (plugging) of unused wells, prevention of leakage of oil, salt water and process fluids. Highly mineralized formation waters, simultaneously extracted during oil production, are pumped back into the subsoil to maintain reservoir pressure. It is not allowed to pump into the bowels of wastewater containing organic pollution, because when they decompose under anaerobic conditions, hydrogen sulfide is formed. The protection of the atmosphere from pollution associated with the operation of oil treatment plants, gas compressor stations, technological transport is carried out with the help of environmental measures common to various industries and transport.
During the extraction and processing of minerals, a large-scale human impact on the natural environment occurs. The resulting environmental problems associated with the extraction of minerals require a comprehensive study and immediate solution.
What is the mining industry characterized by?
V Russian Federation the extractive industry is widely developed, because deposits of the main types of minerals are located on the territory of the country. These accumulations of mineral and organic formations, located in the earth's interior, are effectively used, ensuring the life of people and production.
All minerals can be divided into three groups:
- solid, subdivided into: coal, ores, non-metallic materials, etc .;
- liquid, the main representatives of this category are: fresh, mineral water and oil;
- gaseous, which include natural gas.
Depending on the purpose, the following types of minerals are extracted:
- ore materials(iron, manganese, copper, nickel ores, bauxite, chromite and precious metals);
- building materials(limestone, dolomite, clay, sand, marble, granite);
- non-metallic resources(jasper, agate, garnet, corundum, diamonds, rock crystal);
- mining and chemical raw materials(apatite, phosphorite, sodium chloride and potassium salt, sulfur, barite, bromine and iodine-containing solutions;
- fuel and energy materials(oil, gas, coal, peat, oil shale, uranium ore);
- hydromineral raw materials(underground fresh and mineralized waters);
- mineral formations of the ocean(ore-bearing veins, layers of the continental shelf and ferromanganese inclusions);
- mineral resources of sea water.
The Russian mining industry accounts for a quarter of the world's gas production, 17% of the world's oil, 15% of coal, and 14% of iron ore.
Extractive industries have become the largest sources of environmental pollution. The substances that are emitted by the mining complex have a detrimental effect on the ecosystem. Problems of negative impact of mining and processing industries are very acute, as they affect all areas of life.
How does the industry affect the earth's surface, air, water, flora and fauna?
The scale of development of the extractive industry is striking: when recalculating the volume of extraction of raw materials per one inhabitant of the planet, you will get about 20 tons of resources. But only one tenth of this amount is accounted for by final products, and the rest is waste. The development of the mining complex will inevitably lead to negative consequences, the main of which are:
- depletion of raw materials;
- environmental pollution;
- violation of natural processes.
All this leads to serious environmental problems. You can look at individual examples of how different types of extractive industries affect the environment.
At mercury deposits, the landscape is disturbed, dumps are formed. In this case, the dispersion of mercury, which is a toxic substance, has a detrimental effect on all living things. A similar problem arises in the development of antimony deposits. As a result of the work, there are accumulations of heavy metals that pollute the atmosphere.
In gold mining, technologies are used to separate the noble metal from mineral impurities, accompanied by the release of toxic components into the atmosphere. The presence of radioactive radiation is observed on the dumps of uranium ore deposits.
Why coal mining is dangerous:
- deformation of the surface and coal-bearing seams;
- air, water and soil pollution in the area of the quarry;
- emission of gas and dust during the removal of waste rocks to the surface;
- the shallowing and disappearance of rivers;
- flooding of abandoned quarries;
- the formation of depression funnels;
- dehydration, salinization of the soil layer.
On the territory located near the mine, anthropogenic forms (ravines, quarries, waste heaps, dumps) are created from raw material waste, which can extend for tens of kilometers. Neither trees nor other plants can grow on them. And the water flowing down from the dumps with toxic substances harms all living things in large adjacent areas.
At the deposits of rock salt, halite wastes are formed, carried by precipitation into reservoirs, which serve to supply residents of nearby settlements with drinking water. Near the development of magnesites, there is a change in the acid-base balance of the soil, leading to the death of vegetation. A change in the chemical composition of the soil leads to mutations in plants - a change in color, ugliness, etc.
Agricultural land is also polluted. When transporting minerals, dust can fly over long distances and settle on the ground.
Over time, the earth's crust is depleted, reserves of raw materials decrease, and the content of minerals decreases. As a result, the volumes of extraction and the amount of waste are increasing. One of the ways out of this situation is the creation of artificial analogs of natural materials.
Protection of the lithosphere
One of the methods to protect the earth's surface from the harmful effects of mining enterprises is land reclamation. The ecological problem can be partially solved by filling the resulting excavations with mining waste.
Since many rocks contain more than one type of mineral, it is necessary to optimize technologies, producing and processing all the components present in the ore. This approach will not only have a positive impact on the environment, but also bring considerable economic benefits.
How to preserve the environment?
At the present stage of development of industrial technologies, it is necessary to provide measures for environmental protection. The priority is the creation of low-waste or non-waste industries that can significantly reduce the harmful effects on the environment.
Activities to help solve the problem
When solving the problem of environmental protection, it is important to use complex measures: production, economic, scientific and technical, social.
You can improve the ecological situation with the help of:
- more complete extraction of minerals from the bowels;
- the use of associated petroleum gas by the industry;
- integrated use of all components of rocks;
- measures for water purification in underground mining;
- the use of mine wastewater for technical purposes;
- use of waste in other industries.
During the extraction and processing of mineral resources, it is necessary to use modern technologies to reduce emissions of harmful substances. Despite the costly application of advanced developments, investments are justified by improving the environmental situation.
1The main environmental problems and wastes affecting the natural environment and humans from the activities of uranium have been identified. mining industry... The main substances that pollute the air basin, underground waters of ore-bearing horizons, as well as those that are part of the waste heaps of the rock raised to the surface during the traditional methods of mining and processing of uranium ores, and their effect on humans are considered. The tasks for ensuring the development of uranium mining industries have been identified. Due to the duration of the development cycle of mining enterprises from exploration to production, which is about 20 years, in the near future uranium mining companies should focus on ensuring the future development of uranium mining industries, for which, first of all, it is necessary to formulate and solve the main tasks associated with introducing modern technologies
mining industry
pollutants
dumps of uranium mines
The groundwater
atmosphere
1. Bubnov V.K. Extraction of metals from zagazinennaya ore in blocks of underground and heap leaching stacks / V.K. Bubnov, A.M. Kapkanshchikov, E.K. Spirin - Tselinograd: Zhana-Arka, 1992 - 307 p.
2. Bubnov V.K. Theory and practice of mining for combined leaching methods. / VC. Bubnov, A.M. Kapkanshchikov, E.K. Spirin - M .: Akmola, 1992 - 522 p.
3. Zabolotsky K.A. Optimal complex of hydrogeological and geoecological studies of metal deposits in weathering crusts in relation to their mining by underground leaching: author. dis. ... Cand. - Ekanterinburg: USMU, 2008 - 91 p.
4. Mamilov V.A. Uranium mining by in situ leaching. - M .: Atomizdat, 1980 - 248 p.
5. Tashlykov O. L. Organization and technology of nuclear power. - M .: Energoatomizd, 1995 - 327 p.
6. Titaeva N.A. Geochemistry of isotopes of radioactive elements (U, Th, Ra): author. dis. ... dr. - M .: Moscow State University, 2002 .-- 23 p.
7. Chesnokov N.I., Petrosov A.A. Systems for the development of uranium ore deposits. - M .: Atomizdat, 1972 - 22 p.
Traditional methods of extraction of mineral raw materials and their beneficiation are characterized by a large volume of waste. Waste disposed in large areas, as well as wastewater from concentration plants and mine wastewater, cause disturbances and negative consequences in all components of the biosphere - air and water basins are polluted, as a result of which land resources are degraded, many species of flora and fauna disappear. In the course of analyzing a number of sources, the main environmental problems and aspects that affect the natural environment and humans, as its component, have been identified.
From the activities of the uranium mining industry, first of all, workers of enterprises (miners, equipment operators, etc.) suffer, and secondly, residents of neighboring settlements and nature.
It includes:
● pollution of mine waters with uranium and other radionuclides;
● discharge of wastewater into groundwater;
● washout of radionuclides from contaminated areas by rains and their spreading through the environment;
● intake of radon from mines, waste rock dumps and tailings;
● leaching of radionuclides from tailings with their subsequent discharge into natural waters;
● erosion of tailings systems with dispersal of toxins by wind and water;
● pollution of ground and surface waters by toxic non-radioactive substances such as heavy metals and reagents used in ore processing.
The tracer of uranium pollution can be the isotopic ratio 234 U / 238 U, which in ores and ore residues is close to the equilibrium value, and in surface groundwater significantly exceeds its value.
In Europe, uranium ore was mined either in open pits or in underground mines. At the same time, only 0.1% of the ore was usefully used, everything else is waste. Immediately after World War II, uranium was extracted from shallow deposits, then from deep mines. With the decline in uranium prices on the world market, underground mining became unprofitable and most of the mines were closed. During the active period of mining, large amounts of air contaminated with radon and dust were carried into the air basin. For example, in 1993 from the Sсhlem-Alberoda mine (Saxony, Germany) 7.43 ∙ 109 m3 (that is, the pollution rate was 235 m3 / s) of air with an average radon concentration of 96,000 Bq / m3 was taken out into the air basin.
The main substances that pollute the air in the traditional methods of mining and processing of uranium ores are:
● dust generated in the course of mining, transportation, crushing of ores, storage in dumps and long-term storage of tailings from hydrometallurgical industries, including dust containing radioactive substances. The radioactive substances in mine dust include long-lived emitters (U, Ra, Po, Io, RaD, Th), which can have a harmful effect on living organisms by inhaling contaminated mine air near ventilation units and air discharge points from the production area;
● gases released during blasting operations and as a result of chemical interaction of reagents with ores and intermediate products in the process of hydrometallurgical processing (CO2, CO, H2S, nitrogen oxides, NH3, H2SO4 vapor, etc.).
Despite the well-organized dust suppression at underground mining (the dust content in the mine atmosphere does not exceed 1 mg / m³) during handling, transportation and crushing of ores, as well as during storage of off-balance ores, waste rocks and tailings, only one medium productivity together with a hydrometallurgical plant tens of tons of dust per year. A particularly noticeable amount of dust enters the atmosphere during open pit mining due to the large volumes of overburden and the difficulty of dust suppression in winter.
By lowering the dose for miners, ventilation increased the radiation load on the residents of the surrounding villages. It is important that this load continued after the closure of the mines, since ventilation is carried out during a rather long period of conservation of the mine and its flooding. In 1992, radon levels for the residents of the city of Schlem in Saxony were significantly reduced by changing the mine ventilation: polluted air began to be thrown away from residential areas. In Bulgaria, a closed uranium mine is located right on the outskirts of the village of Eleshnitza, so there is a lot of radon in residential buildings. It is believed that 30% of the lung cancer cases per year among the 2600 villagers are related to the proximity of the mine. But radon and uranium dust emitted by mine ventilation not only directly increase the radiation burden on the population. Analysis of various food products grown in Ronneburg (a uranium mining region in Thuringia) showed that the consumption of local food makes a rather high dose contribution of 0.33 m3 annually, mainly due to wheat grown at the exit of the mine ventilation.
In addition to air pollution, the mining industry contributes to the pollution of the water basin. Large quantities of groundwater are continuously pumped out of uranium mines to keep them dry during mining. This water flows into rivers, streams and lakes. Thus, in river sediments in the Ronneburg region, the concentrations of radium and uranium are equal to 3000 Bq / kg, i.e. 100 times the natural background. In the Czech Republic, the long-term pollution of the Ploucnic River sediments is caused by poor treatment of the mine waters of the Hamr I uranium mine, which was operated until 1989. The river valley is polluted for a stretch of 30 km. Doses received from γ-radiation reach a maximum of 3.1 Gy / h, i.e. 30 times the background. In the Lergue River in France, wastewater from the Herault uranium mining complex resulted in 226 Ra in the sediments of 13,000 Bq / kg, which is almost equal to the concentration of radium in the uranium ore itself.
With regard to the protection of surface and especially groundwater in the case of uranium mining by in-situ leaching methods, the opinions of experts are ambiguous. The discrepancies in estimates are due to the fact that during underground leaching over a number of years of field development, tens and hundreds of thousands of sulfuric acid or other solvent are exhausted to create the necessary concentrations of a dissolving agent in the underground waters of ore-bearing horizons. When dissolving pollution in general terms, the introduction of such an amount of solvent quite naturally gives reason to talk about the pollution of groundwater. As a result of physicochemical processes of underground leaching in technological solutions (productive and working), some components accumulate in quantities that significantly exceed the maximum permissible concentrations for waters used in drinking and economic purposes... In the conditions of sulfuric acid leaching, such components are:
1) the constituents of the solvent and the acidity of the medium;
2) leaching products - both radioactive U, Ra, Po, RaD and stable Fe2 +, Fe3 +, Al3 +, and other cations;
3) technological products of solution processing -,,, Cl- (depending on the applied method of resin desorption).
In the ore-bearing horizon of the mined section of the deposit, groundwater undergoes a significant change in the salt composition. This applies in particular to components such as Fe2 +, Fe3 +, Al3 +,, uranium and acidity (pH). The increase in salinity within the mined ore bodies belongs to the category provided for by the technological regulations, without which it is impossible to mine uranium. The process of converting uranium into solution occurs directly in the ore body, in the watered ore-bearing horizon, in a certain limited space of this horizon. Contamination of groundwater with technological solutions outside the mined part of the deposit along the ore-bearing and adjacent aquifers.
As a rule, in hydrogenic deposits, the ore-bearing horizon is separated from adjacent aquifers by water-resistant strata, which exclude the overflow of leaching and productive solutions into adjacent aquifers. An important measure to prevent the overflow of saline waters into adjacent horizons is their high-quality isolation from the ore-bearing horizon during the construction of wells. The essence of insulation is the correct cementation of the annulus.
Dumps of uranium mines also pose an environmental hazard (Fig. 1). Waste rock is recovered from open pits during the opening of the ore body, during the construction of underground mines, during the laying of drifts through non-metallic zones. Waste heaps of rock raised to the surface usually contain more radionuclides than surrounding rocks.
Some of them are the same uranium ores, but with a uranium content lower than the profitability of mining, which in turn depends on modern technology and economics.
Rice. 1. Danger of dumps of uranium mining enterprises
Rice. 2. Time change in the activity of some radionuclides in uranium ore dumps
All these accumulations of waste pose a danger to local residents, since even after the closure of the mines, they continue to generate radon, which is released and moves into the environment (Fig. 2).
In addition, a number of toxins (not necessarily radioactive) are washed out from waste heaps and pollute groundwater. For example, the waste rock dumps at the Schlem mine have a volume of 47 million m3 and occupy 343 hectares. Moreover, the dumps are located in the upper reaches of the inclined valley, which is densely populated at the bottom. Result: the average concentration of radon in the air of settlements is 100 Bq / m3, and in some of them it is above 300 Bq / m3. This gives additional cases of lung cancer (20 and 60 respectively) per 1000 inhabitants. For southern Ronneburg, the additional lifetime risk of lung cancer is 15 cases per 1000 inhabitants. Given the rapid spread of radon with winds, there is a risk of residents of a wider range: an additional risk of lung cancer is 6 cases annually within a radius of 400 km.
Due to the low content of uranium in the ores, processing hydrometallurgical plants, taking into account the sanitary zones, occupy significant areas, and the volumes of tailing dumps are equal in terms of the amount of mined and processed commercial ores. Tailings ponds not only completely exclude large areas of land from economic use, but are also hotbeds of constant danger due to dust formation: from one square meter of tailings surface per year is carried away from 90 to 250 kg of dust.
Another problem is the leakage of toxins from rock heaps. For example, water leaks from dumps in Schlem / Aue are equal to 2 ∙ 106 m3 annually, half of which flows into groundwater. The so-called waste rock is often processed into gravel or cement for use in the construction of iron or highways... As a result, radioactivity is dispersed over a large region. In the Czech Republic, material with uranium concentrations up to 200 g per ton and radium concentrations up to 2.22 Bq / g was used for road construction until 1991.
Due to the duration of the development cycle of mining enterprises from exploration to production, which is about 20 years, in the near future uranium mining companies should focus on ensuring the future development of uranium mining industries, for which, first of all, it is necessary to solve the following main tasks related to the implementation modern technologies. Namely: ensuring the comprehensiveness and completeness of subsoil development, which implies the complete elimination of loss of raw materials and minimization of the amount of waste by processing them into secondary resources, as well as the extraction of accompanying valuable components. This will increase the profitability of production and attract additional funds for the organization of environmental protection measures in order to reduce the impact of anthropogenic pressure on the environment.
Bibliographic reference
Filonov A.V., Romanenko V.O. ENVIRONMENTAL PROBLEMS OF MINING INDUSTRY ENTERPRISES // Successes of modern natural science. - 2016. - No. 3. - P. 210-213;URL: http://natural-sciences.ru/ru/article/view?id=35850 (date accessed: 02/01/2020). We bring to your attention the journals published by the "Academy of Natural Sciences"
Introduction
The primary processes of destruction associated with drilling, blasting, splitting, crushing, transportation of rock mass, its processing, and enrichment prevail in modern technologies for extracting mineral resources. These processes are accompanied by manifestations of rock pressure, displacement of rocks, rock bumps, sudden outbursts of gas, dust, endogenous and exogenous fires, etc. Often, some of them acquire a significant volume, gas and dust explosions in coal mines are especially dangerous for workers.
1. Water treatment in the mining industry
In the global mining industry, water treatment and wastewater treatment are becoming increasingly important. Water scarcity and stricter environmental management rules have significantly changed the approach to water resources management at mining enterprises.
To be able to reuse it (as process water or to compensate for water shortages in arid regions), improve the coefficient of water consumption and be less dependent on external water supply constraints.
1 Rational use of water. Ways to improve water consumption efficiency and norms
Mining companies use huge amounts of water. Often, just one gold mine spends hundreds of cubic meters of water every hour on technological operations. Wastewater of this volume can pose a serious threat to the environment and population. Unsurprisingly, water costs more than $ 7 billion a year for mining companies around the world.
To the greatest extent, this is explained by the tightening of standards for the rational use of water resources in this industry and the simultaneous strengthening of control over their observance. New standards set limits for each component of emissions, maximum daily load. Particular attention is paid to the protection of human health, aquatic flora and fauna.
Typical tasks and how to solve them
Finding and using alternative sources for example:
Industrial waste water use
Use of treated municipal wastewater
Use of sea and brackish water
Surface water use
Minimizing the use of imported water
A mine's investment in water treatment technology should provide a future proofing solution to wastewater compliance issues, including in the face of significant fluctuations or potential changes in source / mine water quality.
2 Mining water sources
Surface waters (lakes, rivers, seas, etc.).
Groundwater or springs.
Municipal water (in cities).
Wastewater after secondary treatment (after biological treatment plants).
Water from a reservoir or mine (may include runoff, storm water, mine infiltrated water, groundwater, mine drainage, or water from dewatering wells).
Waste storage / dumps.
Depending on the source of water and the area of its use in production, the pollution contained in it can negatively affect production processes (the state of equipment and production efficiency), the health of personnel and other people, and the state of the environment.
1.3 Water treatment technologies in the mining industry
The operation of a mining enterprise, the required treatment technologies and the possibility of using water as drinking water depend on the quality of the water supplied to the enterprise from external sources.
To protect equipment (pumps, nozzles, chillers, longwall equipment), it is necessary to limit the content of mechanical impurities (TSS) in the water used in technological processes. For some applications, it is also necessary to reduce the total mineralization (TDS) or electrical conductivity.
Water from external sources used at the enterprise as drinking water, including in remote areas of work, must be purified from mechanical impurities and microorganisms to the level of compliance with applicable standards.
Water for production processes can be obtained by recycling waste water or discharged mine water for reuse. Alternative sources can also be used to obtain process water, for example, treated pre-treated municipal wastewater, treated surface water or groundwater. Thus, water from these sources can be used in ore recovery or mineral processing technologies, as make-up water for boilers or in cooling towers.
Reservoir waters that have penetrated into the mine, from dewatering wells, discharged from mines, liquid waste or saline process water can be recycled for reuse or discharge. Such treatment should ensure compliance with local regulations governing the composition of water discharged to surface sources or pumped into aquifers.
2. The need to assess and predict the degree of impact of the activities of mining enterprises on the environment (water resources)
Unfortunately, at the present stage of social development, mining is one of the most influencing human activities on the natural environment.
Mining enterprises commissioned or planned for commissioning, from an environmental point of view, are significant sources of disturbance and pollution of all elements of the biosphere. Therefore, the assessment and forecast of the degree of their impact on the environment are very relevant and necessary, since they allow to develop effective environmental protection measures in advance so as not to cause irreparable damage to the environment. Since humanity today cannot do without the extraction and processing of minerals in large volumes, the task of mountain ecology is to minimize the impact of their mining processes on the environment, which is important for ensuring the safety of life.
The fact is that during the extraction of minerals, almost all components of the ecosystem are negatively affected: relief, atmosphere, surface and underground waters, soil and vegetation cover, and fauna. In many cases, as a result of intensive mining and processing of rocks, a technogenic relief remains in the place of the once pristine natural landscape.
The primary processes of destruction associated with drilling, blasting, splitting, crushing, transportation of rock mass, its processing, and enrichment prevail in modern technologies for extracting mineral resources. These processes are accompanied by manifestations of rock pressure, displacement of rocks, rock bumps, sudden outbursts of gas, dust, endogenous and exogenous fires, etc. Often, some of them acquire a significant volume, gas and dust explosions in coal mines are especially dangerous for workers.
The most vividly possible types and scales of various types of impacts of mining activities on the ecosystem can be traced on the example of open-pit and underground mining of coal deposits (Table 1).
The scale of the impact on the environment in different ways of developing coal deposits of the Karaganda and Ekibastuz basins in Kazakhstan
The changing environment and the nature of the negative manifestation of anthropogenic impact The scale of the impact with different methods of development in the open underground123 Hydrosphere: Changes in the hydrogeological regime May manifest itself both on the local and regional scales Manifest on the local scale Changes in the hydrological regime The same The same Changes in the chemical and microelement water composition of the surface and underground water. Exceeding the norms for some indicators can reach hundreds of maximum permissible concentrations Influence is insignificant Changes in the hydrobiological composition of surface water can be significant The same Atmosphere: Pollution with a dust and gas mixture The content of dust in the working area without dust suppression means is significant In the working area of mining combines without dust suppression means, various working conditions can reach very high operating conditions for mountains. pneumoconiosis (silicosis, anthrocosis, dust bronchitis, etc.) Exceeding the border of a mining allotment multiple Local scattering Lithosphere: Complete removal, mechanical destruction of varying degrees, soil degradation. and microelement composition of soils and inhibition of the work of soil microorganisms. Within a mining allotment Activation of cryogenic processes (erosion, solifluction, heaving, landslides, etc.) Within a mining allotment, in some cases in areas adjacent to quarries Within a mining allotment Alienation of additional areas for disposal of production waste (waste dumps, scrap metal, waste tires dump trucks, etc.) Areas comparable to the size of a quarry, littering of the territory inside the mining allotment, expansion of the impact zone due to sawing dumps, the ingress of erosion products from dumps into surface waterways Waste rock dumps occupy an insignificant area within the mining allotment Biosphere: Complete removal, mechanical destruction of varying degrees of degradation of vegetation cover Within the mining allotment, in some cases in areas adjacent to the quarries Within the mining allotment Changes in the nutrition of vegetation growing conditions Over a large area exceeding ten times the size of the mining allotment B mainly limited to the limits of the mining allotment Changes in the microelement composition of plant tissues The same The same Changes in the living conditions of animals ""
As follows from the analysis of the data presented, underground mining of coal deposits in terms of the effect on all components of the natural environment is many times more profitable than open pit mining. Maximum emissions into the atmosphere, discharges of pollutants into surface waters, significant changes in the terrain, the formation of huge volumes of industrial waste (waste dumps, tailing dumps, metal, waste tires, etc.) are most typical for open-pit mining.
It is also important to note that during the liquidation of the enterprise, a significant amount of additional measures will be required for the reclamation of open pits, waste rock dumps, without which the impact on the natural environment will not stop for many years.
1 Polluting effect of mining operations on water bodies
One of the types of environmental impacts of mining during the extraction of minerals is the pollution of water bodies (rivers, lakes, reservoirs, underground aquifers).
Water resources are of great importance for the processes of mining and metallurgical production. The extraction of raw materials and the production of metals require significant volumes of water for processing and cooling. In addition, water is a waste product in many mining processes, and this raises water quality issues in the vicinity of mining. The fact that a lack of adequate water supply can pose a potential threat to production in the energy supply chain cannot be underestimated.
As economic practice shows, the waste waters of the mining and metallurgical complex (MMC) are contaminated with minerals, flotation reagents, most of which are toxic, heavy metal salts, arsenic, fluorine, mercury, antimony, sulfates, chlorides, etc. Thus, in water bodies subject to discharges from mining enterprises, up to 10 MPCs are observed in excess of copper content, up to 6 MPCs - for sulfates and other pollutants.
The water capacity of MMC products assumes the efficiency of using water resources, reflecting the volume of water consumed to obtain a unit of metallurgical products.
The economic activity of coal industry enterprises shows that in mines and open pits, the main pollutant is suspended coal-rock particles, which, getting into water bodies, together with waste water, reduce the transparency of the water, flood the bottom and banks, lead to waterlogging, a decrease in the volume of reservoirs and disturbance in them biological balance. As a result, fish and all living things are gradually dying out. This type of pollution is especially typical for the Karaganda coal basin.
Pollution of groundwater horizons usually occurs due to imperfection of mining and is associated with the fact that part of the polluted mine or quarry water migrates into the disturbed mountain range and brings polluting elements into groundwater. Quite often, part of the surface runoff also gets here. Technogenic pollution carried out from the territory of the enterprise into an open hydrographic network as part of the feed water can get into the groundwater and then spread throughout the geological section.
Waste waters of coal enterprises also include surface runoff waters from dumps of mines, open-pit mines and processing plants, transport communications and other facilities that are located within the mining allotment. As the analysis of the activities of coal mining enterprises shows, an effective measure to limit their harmful effect on water bodies is to take measures to reduce the inflow of water into the mine workings of mines and open-pit mines, which will not only reduce the volume of wastewater and the costs of their transportation and treatment, but also preserve natural reserves and qualitative composition of groundwater.
2.2 Priority directions for reducing (eliminating) the harmful impact of mining enterprises on water resources
To maintain and improve the quality of environmental components and protect human health, business entities must constantly analyze and evaluate their environmental management system in order to identify opportunities for improving it to achieve maximum environmental efficiency. The solution to this problem is impossible without obtaining objective data on the actual state of environmental components in the zone of influence of the production activity of an economic entity (an enterprise for the extraction and processing of minerals) in dynamics.
Thus, the main task of industrial environmental control is to monitor compliance with the established standards for the emission of pollutants into the atmosphere, discharge with wastewater into the hydrosphere, disposal of production and consumption waste and changes in the quality of environmental components over time. As a rule, it is carried out on the basis of a program developed and agreed upon in accordance with the established procedure, which establishes a mandatory list of control points and parameters monitored during control, the frequency, duration and frequency of their determination, the instrumental or calculation methods used.
According to research data, industrial environmental control should include the following main sections:
operational monitoring, that is, control over compliance with parameters technological processes which are sources of pollutants entering the environment;
monitoring of emissions of pollutants into the environment, which consists in determining the amount and composition of emissions into the atmosphere, discharges into the hydrosphere, production and consumption waste;
monitoring of the internal audit of compliance with environmental requirements, the task of which is to analyze the results of industrial environmental control and the compliance of the state of environmental components with regulatory requirements, and in case of exceeding the standards, the development of measures to ensure environmental requirements;
monitoring of actions in emergency situations.
Conducting industrial environmental control allows you to obtain information about the impact of the operation of the facility on the environment. This information is the basis for making decisions regarding the environmental policy of a natural resource user in order to increase the production and environmental efficiency of the environmental management system.
In the future, it seems obvious that there is a need to tighten environmental requirements for violators of environmental legislation in the oil and mining complexes, in the metallurgical and chemical industries, with the application of appropriate sanctions against violating companies. On the contrary, support for companies pursuing an innovative environmental strategy and policy in their activities should consist in their support with the inclusion of projects in the list of applicants for funding from the National Innovation Fund (NIF), among which there should be environmental innovations of Kazakhstani scientists, as well as venture environmental projects.
Tightening economic sanctions against polluting enterprises should be proportional to the scale of pollution - emissions and discharges. Whereas an incentive for polluting enterprises that have begun to reduce their volumes, as well as upon the fact of mastering environmental conservation technologies, confirmed by calculations and their first results, may be their cancellation.
Enterprises with a high potential of nature-saving technologies, systematically mastering them and borrowing transfer technologies of nature conservation, should be provided with monetary compensation that partially or completely covers the costs, in accordance with the effect obtained, as well as bonuses to developers and performers for the creation and development of new technologies based on the results of innovative projects. The provision of a 20% discount on corporate tax and VAT on the volume of products sold is necessary in relation to science-intensive, environmentally-oriented firms that produce environmentally friendly technology and equipment. A system of accelerated reimbursement of capital investments can also be used, including a reduction in the norms and periods of amortization of new environmentally friendly equipment of enterprises.
Conclusion
In the future, mining enterprises, whose activities are closely related to the impact on the environment, are obliged to carry out organizational, economic, technical and other measures to ensure compliance with the quality standards of environmental components (atmospheric air, surface and ground water, soil) in accordance with environmental and sanitary -hygienic norms and rules.
According to the Environmental Code of the Republic of Kazakhstan (RK), entities engaged in special environmental management are required to carry out industrial environmental control, form and submit to the authorized bodies in the field of environmental protection quarterly and annual reports on the results of industrial environmental control in accordance with the requirements established by the Ministry of Environmental Protection. environment of the Republic of Kazakhstan.
To maintain and improve the quality of environmental components and protect human health, business entities must constantly analyze and evaluate their environmental management system in order to identify opportunities for improving it to achieve maximum environmental efficiency. The solution to this problem is impossible without obtaining objective data on the actual state of environmental components in the zone of influence of the production activity of an economic entity (an enterprise for the extraction and processing of minerals) in dynamics.
List of used literature
water treatment mining pollutant
1. Alshanov R.A. Kazakhstan in the world mineral and raw material market: problems and solutions. - Almaty: LLP "Print - S", 2004. - 220 p.
Karenov R.S. Priorities of the strategy of industrial and innovative development of the mining industry in Kazakhstan. - Astana: KazUEFMT Publishing House, 2010 .-- 539 p.
Karenov R.S. Ecological, economic and social efficiency of geotechnological methods of mining. - Karaganda: KarSU Publishing House, 2011 .-- 366 p.
Galiev S., Zhumabekova S. Analysis of resource consumption at the enterprises of the mining and metallurgical complex of the Republic of Kazakhstan // Industry of Kazakhstan. - 2011. - No. 4 (67). - S. 38 - 43.
The mining industry includes 3 main methods of extracting minerals: mine, open-pit, borehole. Each of them has specific environmental problems. The mine method in various varieties has been used since ancient times. It involves the creation of transport mine workings (mine shafts, adits) "to a mineral deposit and a system of workings (longwalls, drifts) intended for mining within the deposit. Environmental problems with this mining method are associated with the formation of dumps from overburden the level of groundwater as a result of their pumping out of mine workings 3-danger of pollution of water bodies by mine (mine) waters.The open method is used for the extraction of solid minerals (coal, oil shale and peat, various ores, more voluminous quarries and open-pit mines, which became possible with the advent of powerful earth-moving equipment. Open way is considered more progressive, since it can significantly improve conditions and increase labor productivity, and allows you to extract minerals. The open pit mines 38% of coal, 88% of iron ore, 96% of chromites and almost 100% of building materials. The load on the environment with this method of production increases many times, in proportion to the increase in the volume of workings. Disturbance of land cover during open pit mining leads to the formation of a "lunar landscape" of open pits and dumps, formed by completely sterile rocks and subject to fluttering, erosion and leaching of soluble components, with pollution of atmospheric air, water bodies and soils of adjacent territories. At coal deposits, the problem of atmospheric pollution is often aggravated by the ability of certain types of coal that fall into the dump from non-industrial seams.
to ignite spontaneously when air is available in the vicinity of large open pits, depression funnels are formed, within which there is a significant decrease in the level of groundwater, leading to the draining of springs and wells. Environmental problems of mine and opencast mining of solid minerals are solved by means of reclamation - a set of works aimed at restoring the productivity and economic value of disturbed lands, as well as improving environmental conditions. Reclamation is carried out at the end of the development of a section of the field or the field as a whole and includes two stages: technical and biological. During technical reclamation, the overburden is filled with underground workings: leveling of the surfaces of open pits and dumps. During biological reclamation, artificial soils are created (based on peat and other materials), landscaping, and stocking of water bodies. If it is impossible to carry out the vertical leveling of the relief, simplified methods of reclamation are used: the creation of reservoirs in the worked out quarries, the landscaping of waste heaps.
Downhole method used mainly for the extraction of liquid and gaseous minerals: natural gases, oil, groundwater. Some types of solid minerals can also be extracted using wells: underground gasification of coal, underground leaching of ores. The downhole method, the use of which has become possible since the end of the 19th century with the development of drilling technology, creates a load on land resources that is significantly less than mine and quarry production. The environmental problems of downhole production are related to the fact that this method affects great depths, where mining and geological conditions are sharply different from the near-surface. The geochemical environment is reducing, practically oxygen-free, pressures reach hundreds of atmospheres, highly mineralized, aggressive formation waters are widespread. Wells irreversibly violate the integrity of aquicludes separating fresh aquifers from zones of slow and very slow water exchange. With a significant scale of extraction of liquid and gaseous minerals, as well as injecting water and solutions to maintain reservoir pressure, and other impacts on reservoirs, there is a redistribution of pressures, temperatures, geochemical parameters, directions and rates of groundwater circulation. External manifestations of technogenically caused changes in the subsoil are the activation of geodynamic processes, including with the intensification of seismicity, changes in water availability, regime and hydrochemical characteristics of aquifers, incl. leading to groundwater pollution. In case of emergency leaks of oil, reservoir waters, process fluids, atmospheric air, soil and surface water are polluted, and damage to the vegetation cover and fauna is caused. Massive pollution of the atmosphere, surface waters and soils occurs during accidents leading to gushing oil and gas emissions. The likelihood of accidental leaks increases with the development of corrosion and wear and tear of equipment in contact with corrosive liquids. So, at the end of the 1980s, about 11 thousand accidents occurred annually per 100 thousand km of oil pipelines in the Tyumen region. To reduce accidents, the pipeline network is reduced by concentrating a number of wells on one site (cluster), pipes with an internal anti-corrosion coating are used. Permanent sources of atmospheric pollution associated with the production and transportation of oil and gas are gas flares, oil treatment plants, gas compressor stations, and technological transport. Utilization of associated gas as fuel or chemical raw material is not always possible, because it may contain a significant admixture of non-flammable components (nitrogen, carbon dioxide). Subsoil protection during well production includes complexes of measures developed on the basis of geoecological studies. They include: regulation of the load on the elements of the tectonic structure in order to prevent activation of faults, isolation of aquifers by cementation of the annulus of wells and elimination (plugging) of unused wells, prevention of leakage of oil, salt water and process fluids. Highly mineralized formation waters, simultaneously extracted during oil production, are pumped back into the subsoil to maintain reservoir pressure. It is not allowed to pump into the bowels of wastewater containing organic pollution, because when they decompose under anaerobic conditions, hydrogen sulfide is formed. The protection of the atmosphere from pollution associated with the operation of oil treatment plants, gas compressor stations, technological transport is carried out with the help of environmental measures common to various industries and transport.
Samples of documents
