How to mine coal. Minerals: Coal. The specifics of coal mining in different coal mines in Russia

Coal fuel has been used by humans since ancient times. Its flammability and heat dissipation, the duration of heat retention in the hearth became the salvation of people in cold periods, which cyclically replaced each other on our planet. Coal is actively used even today; in the fuel and energy complex, it is in the top three raw materials along with oil and gas.

How were coal deposits formed?

Coal deposits were formed in the places of huge green areas. This is an ancient organic matter that remained after the death of tree plantations. In order for the dead plants to become coal, certain conditions are necessary: ​​the wood residues must not rot under the influence of bacteria. This is possible only when they get under the swamp water, and then underground, where oxygen does not enter. Coal is considered a mineral extracted from rock layers at various depths.

How are coal deposits found and developed?

Places where there is coal have long been explored on the planet. Its reserves in different countries are huge, they will be enough for the needs of heating and industry for almost three centuries. But according to geologists, there may be more, since not all parts of the world carried out deep geological prospecting for the presence of coal fuel. The development of coal deposits is relevant and brings tangible income to the states that are engaged in the extraction of this solid black gold. The process of developing deposits is carried out depending on the terrain and the depth of the coal seams.

Coal is one of the most famous fuel resources. The ancient Greeks were the first to learn about the combustible properties of this mineral. How is coal mining carried out in the modern world? Which countries are leading in its production? And what are the prospects for the coal industry in the near future?

What is charcoal and how is it used?

Coal is a solid and combustible mineral, a rock of dark gray or black color with a slight metallic sheen. “This substance flares up and burns like charcoal” - this is how Theophrastus of Eres, a student of Aristotle, described the breed. Coal was actively used by the ancient Romans to heat their homes. And the Chinese learned how to make coke from it back in the 1st century BC.

How was coal formed? In ancient geological eras, large areas of the earth's surface were covered with dense forests. Over time, the climate changed, and all this wood pulp was buried under the earth. Under conditions of high temperature and pressure, dead vegetation turned first into peat, and then into coal. Thus, powerful layers enriched with carbon appeared underground. The most active coal was formed in the Carboniferous, Permian and Jurassic periods.

Coal is used as an energy fuel. It is on this resource that most of all thermal power plants operate. In the XVIII-XIX centuries, the active mining of coal became one of the decisive factors in the industrial revolution that took place in Europe. Today, coal is widely used in ferrous metallurgy, as well as in the production of so-called liquid fuels (by liquefaction).

Based on the amount of carbon in the composition of the rock, there are three main types of coal:

  • brown coal (65-75% carbon);
  • hard coal (75-95%);
  • anthracite (over 95%).

Coal mining

To date, the total volume of industrial coal reserves on our planet reaches one trillion tons. Thus, this fuel resource will be enough for humanity for many years to come (unlike the same oil or natural gas).

Coal mining is carried out by two methods:

  • open;
  • closed.

The first method involves the extraction of rock from the bowels of the earth in quarries (coal cuts), and the second - in closed mines. The depth of the latter varies widely from several hundred meters to one and a half kilometers. Each of these coal mining methods has its own advantages and disadvantages. So, the open method is much cheaper and safer than the underground one. On the other hand, mines cause much less harm to the environment and natural landscapes than quarries.

It should be noted that coal mining technologies do not stand in one place. If a hundred years ago, primitive carts, picks and shovels were used to mine coal seams, now the latest technical machines and equipment (jackhammers, harvesters, augers, etc.) are used for the same purposes. In addition, a completely new method of extraction is being developed and improved - hydraulic. Its essence is as follows: a powerful jet of water crushes a layer of coal and carries it into a special chamber. From there, the rock is delivered directly to the factory for further enrichment and processing.

Geography of world coal mining

Coal deposits are located in the world more or less evenly. Deposits of this resource are present on all continents of the planet. Nevertheless, about 80% of all deposits are located in North America and in the post-Soviet countries. At the same time, one sixth of the world's coal reserves are contained in the subsoil of Russia.

The largest coal basins of the planet are Pennsylvania and Appalachian (USA), Henshui and Fushun (China), Karaganda (Kazakhstan), Donetsk (Ukraine), Upper Silesian (Poland), Ruhr (Germany).

As of 2014, the top five leading hard coal producing countries in the world are as follows (in brackets is the percentage of global coal production):

  1. China (46%).
  2. USA (11%).
  3. India (7.6%).
  4. Australia (6.0%).
  5. Indonesia (5.3%).

Problems and prospects of the coal industry

The main problem of the coal mining industry, of course, is environmental. Fossil coal contains mercury, cadmium and other heavy metals. When extracting rock from the ground, all this gets into the soil, atmospheric air, surface and groundwater.

In addition to the damage caused to the environment, the coal industry is also associated with huge risks to human life and health. First of all, it concerns the miners. Excessive dust content in the air in closed mines can lead to serious diseases such as silicosis or pneumoconiosis. We should not forget about the large number of tragedies that annually claim the lives of hundreds of coal industry workers around the world.

But, despite all the problems and dangers, mankind is unlikely to be able to abandon this fuel resource in the near future. Especially against the background of the rapid reduction of oil and gas reserves in the world. To date, the coal mining industry is dominated by an upward trend in anthracite production. In some countries (in particular, in Russia, Turkey, Romania) the production of brown coal is growing.

Coal mining in Russia

Russia was first introduced to this mineral by Peter the Great. While relaxing on the banks of the Kalmius River, the king was shown a piece of black rock that burned beautifully. “If not for us, then this mineral will be useful for our descendants,” the sovereign rightly summed up then. The formation of the Russian coal industry took place in the first half of the 19th century.

To date, the volume of coal production in Russia is over 300 million tons annually. In general, the country's bowels contain about 5% of the world's reserves of this fuel resource. The largest coal basins in Russia are Kansk-Achinsk, Pechora, Tunguska and Kuzbass. Over 90% of all deposits in the country are located in Siberia.

Coal is a sedimentary rock that forms in the earth's seam. Coal is an excellent fuel. It is believed that this is the most ancient type of fuel used by our distant ancestors.

How coal is formed

For the formation of coal, a huge amount of plant matter is needed. And it is better if the plants accumulate in one place and do not have time to decompose completely. The ideal place for this is swamps. The water in them is poor in oxygen, which prevents the vital activity of bacteria.

Vegetation mass accumulates in swamps. Not having time to completely rot, it is compressed by the following soil deposits. This is how peat is obtained - the source material for coal. The next layers of soil, as it were, seal the peat in the ground. As a result, it is completely deprived of access to oxygen and water and turns into a coal seam. This process is lengthy. So, most of the modern reserves of coal were formed in the Paleozoic era, that is, more than 300 million years ago.

Characteristics and types of coal

(Brown coal)

The chemical composition of coal depends on its age.

The youngest species is brown coal. It lies at a depth of about 1 km. There is still a lot of water in it - about 43%. Contains a large amount of volatile substances. It ignites and burns well, but gives little heat.

Hard coal is a kind of "middling" in this classification. It occurs at depths up to 3 km. Since the pressure of the upper layers is greater, the water content in coal is less - about 12%, volatile substances - up to 32%, but carbon contains from 75% to 95%. It is also highly flammable, but burns better. And due to the small amount of moisture, it gives more heat.

Anthracite is an older breed. It occurs at depths of about 5 km. It has more carbon and almost no moisture. Anthracite is a solid fuel, it ignites poorly, but the specific heat of combustion is the highest - up to 7400 kcal / kg.

(Anthracite coal)

However, anthracite is not the final stage in the transformation of organic matter. When exposed to harsher conditions, coal transforms into shuntite. At higher temperatures, graphite is obtained. And when subjected to ultra-high pressure, coal turns into diamond. All these substances - from a plant to a diamond - are made of carbon, only the molecular structure is different.

In addition to the main "ingredients", the composition of coal often includes various "rocks". These are impurities that do not burn, but form slag. Contained in coal and sulfur, and its content is determined by the place of formation of coal. When burned, it reacts with oxygen and forms sulfuric acid. The less impurities in the composition of coal, the higher its grade is valued.

Coal deposit

The place of occurrence of coal is called a coal basin. Over 3.6 thousand coal basins are known in the world. Their area occupies about 15% of the earth's land area. The largest percentage of deposits of the world's coal reserves in the United States - 23%. In second place - Russia, 13%. China closes the top three leading countries - 11%. The largest coal deposits in the world are located in the USA. This is the Appalachian coal basin, whose reserves exceed 1600 billion tons.

In Russia, the largest coal basin is Kuznetsk, in the Kemerovo region. The reserves of Kuzbass amount to 640 billion tons.

The development of deposits in Yakutia (Elginskoye) and in Tyva (Elegestskoye) is promising.

Coal mining

Depending on the depth of the coal, either a closed mining method or an open one is used.

Closed, or underground mining method. For this method, mine shafts and adits are built. Mine shafts are built if the depth of coal is 45 meters or more. A horizontal tunnel leads from it - an adit.

There are 2 closed mining systems: room and pillar mining and longwall mining. The first system is less economical. It is used only in cases where the discovered layers are thick. The second system is much safer and more practical. It allows you to extract up to 80% of the rock and evenly deliver coal to the surface.

The open method is used when the coal is shallow. To begin with, an analysis of the hardness of the soil is carried out, the degree of soil weathering and the layering of the covering layer are ascertained. If the ground above the coal seams is soft, the use of bulldozers and scrapers is sufficient. If the upper layer is thick, then excavators and draglines are brought in. A thick layer of hard rock lying above the coal is blown up.

The use of coal

The area of ​​use of coal is simply huge.

Sulfur, vanadium, germanium, zinc, and lead are extracted from coal.

Coal itself is an excellent fuel.

It is used in metallurgy for iron smelting, in the production of iron, steel.

The ash obtained after burning coal is used in the production of building materials.

From coal, after its special processing, benzene and xylene are obtained, which are used in the production of varnishes, paints, solvents, and linoleum.

By liquefying coal, a first-class liquid fuel is obtained.

Coal is the raw material for producing graphite. As well as naphthalene and a number of other aromatic compounds.

As a result of the chemical processing of coal, more than 400 types of industrial products are currently obtained.

Coal mining as an industrial sector became widespread at the beginning of the 20th century and to this day continues to be one of the most profitable types of mining of mineral deposits. Coal is mined commercially all over the world.

Contrary to popular belief, this fossil is used not only as a quality fuel. In the middle of the twentieth century, the coal industry gave a powerful impetus to the development of scientific research on the extraction of hydrocarbons from minerals.

Where is mining

The largest coal-producing countries are China, the USA, and India. ranks 6th in the world ranking in terms of its production, although it is in the top three in terms of reserves.

Brown coal, hard coal (including coking coal) and anthracite are mined in Russia. The main coal-mining regions in Russia are the Kemerovo region, the Krasnoyarsk Territory, the Irkutsk region, Chita, Buryatia, and the Komi Republic. There is coal in the Urals, the Far East, Kamchatka, Yakutia, the Tula and Kaluga regions. There are 16 coal basins in Russia. One of the largest - more than half of Russia's hard coal is mined there.

How coal is mined

Depending on the depth of the coal seam, its area, shape, thickness, various geographical and environmental factors, a certain method of coal mining is selected. The main methods include the following:

  • mine;
  • developments in a coal quarry;
  • hydraulic.

In addition, there is open-pit coal mining, provided that the coal seam lies at a depth of no more than one hundred meters. But this method is very similar in form to quarry coal mining.

mine method

This method is used from great depths and has an undeniable advantage over open methods of coal mining: coal at great depths is of better quality and practically does not contain impurities.

To access the coal seams, horizontal or vertical tunnels (adits and mines) are drilled. There are known cases of coal mining at a depth of up to 1500 meters (Gvardeyskaya, Shakhterskaya-Glubokaya mines).

Underground coal mining is one of the most difficult specializations due to a number of dangers:

  1. Constant threat of groundwater breakthrough into the mine shaft.
  2. The constant threat of a breakthrough of associated gases into the mine shaft. In addition to possible suffocation, a special danger is explosions and fires.
  3. Accidents due to high temperature at great depths (up to 60 degrees), careless handling of equipment, etc.

In this way, approximately 36% of the world's coal reserves are extracted from the earth's interior, which is 2625.7 million tons.

open way

According to their classification, developments in a coal quarry belong to an open method of coal mining, since they do not require drilling mines and adits to a great depth.

This method of mining consists in undermining and removing overburden (a layer of excess rocks above coal deposits) from the mining site. After that, with the help of excavators, water guns, bulldozers, crushers, draglines and conveyors, the rock is crushed and transferred further.

This method of coal mining is considered less safe than closed (mine). But he also has certain risk factors associated with careless handling of equipment and large-sized vehicles, the possibility of poisoning with exhaust gases and substances accompanying machine activity.

A significant disadvantage of this method is considered to be causing great harm to the environment due to the removal of a large area of ​​the land layer and its accompanying natural elements.

The open-pit method is considered one of the most widespread in the world - it produces more than 55% of coal per year, which is 4102.1 million tons.

It was first used in the Soviet Union in the 30s of the twentieth century. It involves the extraction of coal in deep mines, while transporting coal to the surface occurs with the help of water jets under tension. This method made it possible to use the lack of underground coal mining - groundwater - to their advantage.

Recently, hydraulic coal mining is considered one of the most respectable methods. It is able to replace the laborious and dangerous process of coal mining by miners, instead of which water will act as a destructive and lifting force.

The disadvantages of this method of coal mining include the following:

  • constant contact of working tools and mechanisms with water and rock;
  • certain difficulties in replacing or repairing working equipment;
  • dependence of the process of coal mining on the thickness, angle of inclination and hardness of the rock.

This method produces approximately 7.5% of coal annually, which is 545.5 million tons.

 

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