Coal gives people. Coal

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fossil coal- the first type of mineral fuel used by man. Its gathering from the surface near the coasts of the seas and rivers, where the outcrops of coal seams were eroded, began in the Paleolithic and continued until the 16th century. Small deposits were developed, lying shallow from the surface of the earth. Collected or mined in a primitive manual way in small mine workings, coal was used for heating dwellings and blacksmithing.

Fossil coal: From the history of coal mining

Despite the fact that mining had already become a relatively highly developed industry by the Middle Ages, and the mines reached considerable depths, it was considered inappropriate for coal mining to carry out labor-intensive work on the construction of mines. But over time, the demand for coal grew, and as convenient deposits dried up, open-pit mining was gradually replaced by underground. In very rare cases, in those places where there were outcrops of thick coal seams (Poland, Pennsylvania in the USA), their open mining was carried out until the 19th century.

The shafts of the first mines were shallow and wide wells. Later, they deepened to several tens of meters and expanded in their lower part. It was no longer profitable to abandon them after all the coal had been excavated and lay new ones nearby. Horizontal and inclined workings began to be carried out. From the base of the trunk to different directions longitudinal branches were laid, between which pillars of rock were left for fastening the vaults. In the Middle Ages, mines became multi-storey: workings were laid from a vertical shaft at different depths. Immediately after the extraction of coal, in order to prevent collapses, the working space was reinforced with wooden posts, and later with cages in the form of quadrangles made of crosswise folded wooden beams.

The development and improvement of mining was directly related to the beginning of the industrial revolution. The need for cheap fossil fuels increased dramatically after the invention of the steam engine by James Watt, which made it possible to replace manual labor with machine labor. The increase in the number of machines in various industries has caused an increased demand for metal. And the rapid growth of metallurgy, in turn, led to the middle of the XVIII century. to massive deforestation. So, in England, metallurgical production was in danger of being curtailed due to a lack of fuel resources, since forest areas were almost completely destroyed. Severe economic necessity forced a return to the already forgotten ideas of the chemist Johann Becher, who discovered in 1681 a new method for producing coke and tar from peat and coal:

« Holland has peat, England has coal, but both are almost never used for burning in domestic ovens or for smelting. I found a way to turn both of them into good fuel, which not only does not smoke or stink, but also gives a fire as strong as charcoal for melting.».

By the 18th century The development of hard coal was started at the outcrops in the Ruhr basin (the largest coal basin in Western Europe, located on the territory of modern Germany), Saarbrücken (France), near Plauen (on the border of modern Germany and the Czech Republic).

The first information about the search and exploration of fossil coals in Russia dates back to the reign of Peter I, when special expeditions were organized. In 1721, coal deposits were discovered on the territory of the modern Donbass, the Moscow Region basin, on the Tom River (Kuzbass). For the first time, deposits began to be developed by the mine method in the area of the city of Kizel in the Urals, the city of Tula (Podmoskovskaya basin). Built in the area of modern Lisichansk (Ukraine), the mine began to produce coal in 1796, remaining the main coal mining enterprise of the Russian Empire for more than a century.

In the 19th century the mining industry developed rapidly. The extraction of all minerals, especially coal, has steadily increased. Over the past three decades - six times. And by the end of the century, coal won the world leadership in terms of the value of the mined product (according to German experts - more than 5 billion marks). Iron and steel (just over 2 billion marks) are in second place, and gold is in third place (about 800 million marks).

Coal mining by individual countries on turn of XIX-XX centuries distributed as follows:

	Production volume (in tons)		Production volume (in tons)
Europe		Asia
Great Britain
Germany
		North America
Austria-Hungary		United States

		Africa
		Transvaal
		Australia
		In others countries
Total in Europe	396 059 600	Total	186 390 600
Total in the world - 582 450 200

Coal mining

Despite the rapid pace of development of the coal mining industry in Russia (primarily in the Donbass), it did not cover all the needs of the domestic industry and railway transport. On the eve of the First World War, about 15% of coal was imported from abroad. Almost all coal-mining processes were carried out manually, although, for example, several dozen coal-cutting machines successfully worked in the mines of Donbass.

Academician of the Academy of Sciences of the USSR A.M. Terpigorev (1873-1959) - the largest specialist in the field of exploitation of coal deposits, recalled the state of mining at the turn of the 19th-20th centuries. in the following way:

« The anthracite mine was a small enterprise that could not be seen from a distance. A low tower with rotating pulleys, a small wooden overhead building, near which an office was located».

From the overhead building down the shaft, the miners were delivered by a crate. Downstairs in the near-stem yard there was no lighting, sometimes a small smokehouse was hung, which was called "God help". It was filled with mineral oil or crude oil. The wick, when burning, gave a small flame and a lot of soot, the light was dim, barely visible. The near-stem yard is a more or less wide working, as tall as a man. As you move away from the center, the height decreased to about a meter. A longitudinal drift began from it - a long narrow corridor, with laid rails and a groove along which water flowed. The length of the corridor, at the end of which the face was directly located, increased with the development of coal and could reach a kilometer. The height of the arches with increasing distance, on the contrary, decreased.

And V.V. Veresaev in the essay " Underworld" wrote:

« You walk bent low, your back hurts, your knees tremble... You have to crawl along a hole three-quarters of a arshin high [arshin - just over 70 cm]. You try to move on all fours - it hurts unbearably, you beat your back against a rough arch; you start to crawl - the stones scattered on the way tear up your knees and hands. There is a small light ahead. We pressed against the walls; a worker crawled along the aisle quickly, like a cat, on all fours, dragging a sled loaded with coal behind him on a rope. This is a luger; throughout the twelve-hour team, he crawls back and forth, carrying coal from the lava to the longitudinal one, where the wagoners load this coal into the wagons. Man turns into a quadruped».

To break off the coal, the workers used a pickle - a pointed steel blade, put on a wooden handle. Kylo with a plug-in interchangeable tip (tooth) was called the butt and made it possible to change the blunt part without rising from the face to the surface. For each miner (or cutter), the artel worker determined the amount of work, dividing the front of work along the length into sazhens. The workers sat down along the coal seam at some distance from each other, as they usually sat down on a long wooden village bench. This is where the term lava comes from. For 12 hours of continuous work, the cutter had to make cuts in the form of a wide slot for a given length (2-3 fathoms) and a set depth, usually not exceeding the length of the wooden handle of the butt. This was done in order to facilitate the subsequent breaking of the coal seam and amounted to approximately 120-140 pounds (about 2 tons). Fastening the face was also the responsibility of the cutters, it was an additional burden and was not paid.

After the miners, the miners came into the lava. Soft coals were beaten off with the same butt, stronger ones - with a crowbar, wedges and a heavy hammer (about 5 kg), which was called a "bastard". The broken coal was loaded into wooden sleds on skids by other workers - rakers (or pilers). And then it was taken out by sledgers (or drafters) to the rail track, along which it was already delivered to the lifting stand. The sled with an iron-wrapped box weighed about 3 poods, they contained up to ten poods of coal (total total weight was more than 200 kg).

« The haulers, mostly teenagers, fastened to the boxes with iron chains, quickly on all fours, like tame bears, ran up to the seam and sat down, waiting for the loaders to fill the boxes. And at the first cry of “go!”, they hurriedly got on all fours and slowly, with great difficulty, dragged the boxes to the main avenue, where haulers with square wagons were already waiting for them, taking the booty to the lifting platform. All this work took place in darkness, in closeness and heat, reaching up to 30 degrees. The miners, especially the drafters, were literally bathed in their own sweat. To prevent their feet from slipping on wet stone, the heavy boots of the drafters were shod. And when they ran on all fours along the mine, ringing with chains, their shod legs produced a characteristic iron knock, reminiscent of the stomp of horses on a stone pavement.»

A.I. Svirsky. "In the dark" .

At the exit from the lava, haulers' assistants, teenagers of 13-14 years old, were reloading the mined coal from sleds into trolleys. Each trolley with a capacity of 30-35 pounds (about half a ton.) was rolled along the rails to the lifting stand by one person - a hauler. Some mines used horse-drawn haulage. The stable was arranged right underground. The horses that lived in it very soon lost their sight, adapting to life in almost complete darkness, like moles. In the near-barrel yard, the trailer was driven into a cage, which was raised to the surface with the help of a steam engine. The same cage at the end of the shift lifted workers from the mine

Working conditions in large mines and small mines were almost the same. The differences were only in the depth of development, the number of workers and production volumes. At one of the largest mines in the world - Queen Louise (Upper Silesia) in late XIX centuries, coal seams reached a thickness of 10-15 meters, at least 8,400 people were employed in the work, and the annual production was about 2 million 700 thousand tons. If we take into account the carrying capacity of a railway car of that time (10 tons), then we can calculate that 270,000 cars will be needed to load all this mass of coal. With a length of one car about 8 meters, the train would stretch for 2160 kilometers. Which is approximately equal to three distances between St. Petersburg and Moscow.

Any mine began with the fact that the coal seam was connected to the day surface by a vertical working - a mine shaft - with a diameter of several meters and a depth of up to several hundred meters, a second - ventilation - shaft was made, horizontal corridors were laid connecting the coal seam with both shafts, along which the miners moved, the fixing timber, the extracted coal was transported. Special shelves were installed over the entire height of the trunk, like scaffolding, on each of which a worker stood. From the bottom of the face, the rock was lifted up, throwing it from shelf to shelf. Raised to the surface, the rock was transported to the dump on wheelbarrows. Somewhat later, they began to use a manual gate with a tub on a rope. Horse traction was also used.

The extremely time-consuming work itself was even more complicated if the workings fell into the aquifer - quicksand. Groundwater posed a serious threat. While they were leaking in small quantities, they were manually collected in buckets, pumped out with special mechanisms, taken through special grooves to the part where the coal had already been selected. If the water broke through with a powerful stream, it was no longer possible to save the mine and the miners.

The deeper the shaft went underground, the greater the problem became providing air access. At depth, it is motionless and saturated with vapors of water and various gases. Therefore, in order for a person to work in a mine, fresh air must be continuously supplied there. In ancient times, all efforts were aimed at creating and maintaining natural ventilation. Jets of air were directed into the mine using a wooden shield installed at the entrance or (later) a system of weather vanes called "vetrogons", the wings of which rotated under the influence of wind force and thereby pumped air. Special furnaces were used, installed in the upper drift of the mine, in which the fire was constantly maintained. The heated air rose up the shaft of the mine, in its place came from the lower workings of the colder one.

The increase over time in the number of people working in the mine, the use of horses, the widespread use of blasting, necessitated a forced ventilation device. In the Middle Ages, air was pumped with the help of bellows, driven by the simplest manual gate, which was replaced by a horse drive. Even later, piston pumps and fans appeared. The latter, gradually improving, turned into the twentieth century. in centrifugal and propeller.

In addition, some coal seams constantly emit poisonous gases. Hydrogen sulfide is recognized by its pungent odor, reminiscent of the smell of rotten eggs. Sulfur dioxide acts on the mucous membrane of the eyes, causing lacrimation, for which it was nicknamed "eye-eater". Carbon dioxide is released during explosions, from coal seams, during rotting of the fastening timber, during the breathing of people. Some coals emit methane. In combination with air, it is an explosive mixture, ready to detonate from any spark. Methane is twice as light as air, therefore it accumulates at the top, has no smell, and therefore its presence can only be detected with the help of special instruments. All these gas impurities in a certain concentration make the air unbreathable. M.V. Lomonosov noted at the time that in deep mines, which are further underground in many directions and there are few mines, from the very surface of the dug, steam is usually collected, which is harmful to human health. It comes from fatty stone oil, from sulfur and arsenic, and while digging and breaking mountains with the weight of stone and earthen dust, it diverges through the adits and in them the toiling people injure the chest with its poison. This was also noticed by the miners by the heavy smell that wanders in the mines, occupies the spirit, extinguishes the candles, and this volatile poison turns out to be especially so that it sometimes catches fire in the mines.».

Coal dust also has the ability to explode. The cause can be not only open fire, but also detonation. Dust, formed during the destruction of the seam, during the extraction and transportation of coal, accumulates in all branches of mine workings. If there was a gas explosion, it was no longer limited to a certain area, as it would be in a well-ventilated room - the detonation from it caused a dust explosion throughout the mine. For a long time, the only way to fight was to moisten underground workings, since wet dust became harmless. However, it was not possible to continuously water huge areas, especially since the water quickly evaporated. Slackening turned out to be somewhat more effective - sprinkling places of accumulation of coal dust with some crushed inert mass. The most suitable for this is fine shale dust, which, mixed with coal, made it non-combustible and explosion-proof. Barrier barriers of inert dust also fully justified themselves: under the roof across the drift, shelves were hung with the same crushed clay shale poured on them, which was swept away from the overturned shelves by an explosive wave, mixed with coal dust and prevented the spread of the explosion. However, these methods also had a significant drawback: dust suspension clogged the air, further exacerbating the ventilation problem.

A more dangerous way to prevent explosions was to burn off the explosive gas. After the end of the shift, when the miners rose to the surface, a gas burner descended into the empty mine. Dressed in a wet sheepskin coat, he crawled through the underground galleries, holding outstretched hand an open lamp or torch. If explosive gas appeared under the arches, it exploded, a fiery wave swept along the drifts, all the accumulated gas burned. By morning, the workings were ventilated, and new shift miners descended into the mine. The relative safety of work was often provided at the cost of the life of a gas burner.

Explosions in mines led to the mass death of miners from collapses, fire, water, poisonous gases, and suffocation. The number of victims could reach several hundred people. Rescue work began with the resumption of natural air circulation, and only after the hazardous gases formed as a result of the explosion were removed from the face, they began to rescue the survivors and evacuate the corpses. In the event of a strong fire, so that the fire did not spread along the drifts, they closed the ventilation, installed walls made of bricks with clay, thereby blocking access to the oxygen ignition source.

Often, fires and explosions were caused by torches and smoke lamps used for lighting - ordinary household lamps that were not suitable for underground work. Actually, miner's lamps appeared only by the 18th century. They were of the torch and lantern type, filled with oil and attached to the wooden posts of mine supports or installed in niches. This type of mine lamps were much more convenient to use, but easily ignited the coal dust contained in the air. If this happened near a crack from which gas was released, it exploded, causing significant destruction, which further increased the flow of gas from old workings and provoked new explosions. At the same time, it absorbed great amount oxygen, and those workers who survived the explosion died of asphyxiation.

After a series of major disasters at the Newcastle mines in 1809, 1812 and 1815, caused by explosive gas explosions, the English chemist G. Davy invented a fundamentally new design of a mine lamp, the safety effect of which was achieved through the use of a special fine-mesh metal mesh, which was installed on an ordinary oil lamp. In some designs, in addition, the supply of various neutral gases released from combustion products (nitrogen, carbon dioxide) into the explosive mixture flowing to the lamp was used. Such lamps went out in an explosive environment.

In the middle of the XIX century. Wolf's gasoline lamps, Chenot's alcohol and acetylene lamps appeared. They have become widespread not only because of their relative safety, but also due to the ability to use them to determine the presence of explosive gas in the mine atmosphere and even measure its percentage by flame height. Locks were introduced into the design of shaft lamps, excluding their spontaneous unwinding and opening. It became possible to kindle an extinguished lamp without opening it - with the help of a built-in igniter. Wolf lamps in Russia were called "konogonki" and were produced at the factories and workshops of the Yekaterinoslav mining and industrial society in southern Russia. They were used in mines with a high content of explosive gases until the 1940s. as indicators on a par with electrical ones. The latter appeared in the 70s. 19th century as a result of the work of Russian scientists P.N. Yablochkova, A.N. Lodygin, V.N. Chikolev. In 1886, the first storage lamps appeared in Belgium, France and the USA. But due to the high cost and significant weight, their widespread use began only in 1912. In Russia, electric storage lamps were practically not used. Their production was started only in 1932 in Kharkov. In the USSR, non-gas mines used acetylene lamps (the so-called "carbides"), for mines with a high gas content in 1950, hand and head storage lamps were introduced. Since the 1960s Incandescent lamps have been replaced with fluorescent ones. In the late 1980s, serial production of head explosion-proof mine lamps of the SGG type with rechargeable batteries was launched. For lighting underground workings, stationary mine lamps of increased reliability are also used.

Spontaneous combustion of coal seams in the bowels of the earth, as a result of which a large amount of combustible gas is released to the surface, fires in mines, which destroyed huge reserves of coal that could not be extinguished for years, led to the idea of underground coal gasification. Moreover, it is absolutely unprofitable to develop seams up to half a meter thick. D.I. wrote about this for the first time. Mendeleev in 1888:

« Probably, in time, even such an era will come when they will not remove coal from the earth, but there, in the earth, they will be able to turn it into combustible gases and they will be distributed through pipes over long distances».

The practical implementation of underground gasification began already in Soviet times in the Donetsk and Moscow region coal basins. However, the discovery of rich oil deposits and natural gas with the relative cheapness of their extraction and processing, high calorific value, lack of ballast, good transportability, they first (by the 1960s) led to the predominance of the share of oil over coal in the world fuel and energy balance, and somewhat later to the rapid depletion and development of a number of deposits. The commissioning of hard-to-reach deposits at great depths of the seas and oceans and remote uninhabited areas caused a significant increase in prices for oil, gas and oil products and the energy crisis of the early 1970s. The result has been an increase in the importance of fossil coals in the global economy.

Introduction to mining in the twentieth century. high-performance machines made it possible, on the one hand, to modernize underground mining, and, on the other hand, to return to open-pit mining. With full mechanization, work on the surface is simpler, more convenient, and more economical than underground work. Coal mining is carried out using deep trenches that cut through the rocks, under which there is a coal seam. Therefore, the resulting quarry is called a cut. Various types of excavators are used for work. Waste rock was initially transported by trains with steam or electric locomotive traction, later transport and dump bridges were put into operation, the belt conveyors of which carried the removed waste rock to the dump on the opposite side of the quarry. In a similar way, coal itself is delivered from the quarry to the surface to the loading bins.

In addition to the three technological directions of coal mining (underground mechanical mining, underground gasification, open pit mining), there is one more. Hydraulic coal mining is an underground mining of coal deposits, in which the processes of excavation, transportation and lifting of coal to the surface are performed by the energy of the water flow. The source of water is most often the inflow of groundwater into the mine.

Choice coal mining method depends on a number of conditions and is determined on the basis of the results of a complex of exploration works, which include the following stages:

Prospecting works that allow, using a certain set of signs (direct and indirect), indicating the presence of coal-bearing formations, to discover new deposits or to estimate prospectively areas where the presence of industrial coal-bearing is already known. They allow to give a preliminary (general) geological and industrial assessment of the identified deposits.

Preliminary reconnaissance. It is carried out with a positive result of the search work. It gives a more detailed picture and establishes general patterns in the change in the morphology of coal seams and coal quality, the degree of complexity of the tectonics of the deposit, the comparative value of individual parts of the deposit. The main goal is to timely establish the feasibility of continuing exploration work.

Detailed intelligence. Required if the deposit is recognized as suitable for industrial development. Possible consumers of coal, basic requirements for its quality, method of opening a deposit, technical boundaries, production capacity of a mine or a cut, location, approximate terms for mining areas for the next 10-15 years are considered. The details of the geological structure of the deposit, its structural features, morphology, bedding conditions, coal quality, mining and geological conditions of development.

Additional exploration. It is carried out at deposits previously explored in detail, but not commercially developed, or at already developed ones. Newly identified coal reserves are calculated and approved, and previously approved reserves are re-evaluated.

An integral part of the exploration process is hydrogeological research carried out in parallel with the main exploration work: potential surface and groundwater resources are determined, which will participate in the watering of mine workings or be used as sources of water supply.

When conducting engineering geological studies, the presence of permafrost, the possibility of landslides, mudflows, avalanches are established, the degree of stability of the roof rocks, the main working layers, the location of areas of structural weakening are predicted, recommendations are developed to prevent phenomena that complicate mining operations. For open development coefficients and volumes of overburden, slope angles of the sides of the section are calculated, the equilibrium conditions of natural slopes are evaluated during their undermining and additional load by dump rocks.

Industry and technology. V.5: Mining and metallurgy. - St. Petersburg: Type. t-va "Enlightenment", 1904. - S. 252

Glushkov A.I., Kondyrev B.I. Security environment underground gasification of coal. Analytical review. - Novosibirsk, 1993. P 3-4

The message about coal can be used in preparation for the lesson. The story about coal for children can be supplemented with interesting facts.

Report about hard coal

Coal is a solid, exhaustible, non-renewable mineral that a person uses to obtain heat by burning it. According to the classification, it belongs to sedimentary rocks. Coal as a source of energy, people began to use in antiquity along with firewood.

How is coal formed?

Coal appeared on Earth about 300-350 million years ago, when tree-like ferns flourished on primeval swamps and the first gymnosperms began to appear.

It is believed that coal was formed as a result of the deposition of wood. There were ancient forests, the trees of which accumulated in swamps, where, without access to oxygen, the activity of bacteria decomposing plant residues is reduced to zero, peat is formed, and then, in the process of burying these residues, coal is formed under high pressure and temperature.
So for the formation of coal requires the occurrence of peat at a depth of three kilometers. At this depth, a twenty-meter layer of peat will turn into coal with a seam thickness of two meters.

Types of coal

All types of coal lie in layers and their locations are called coal basins. mined today different types coal.

Anthracites are the hardest grades with great depth and maximum combustion temperature.
Hard coal - many varieties mined in mines and open way. It is widely used in many areas of human activity.
Brown coal - formed from the remains of peat, the youngest type of coal. It has the lowest combustion temperature.

How is coal mined?

Previously, hard coal was simply collected in places where the seam came to the surface. This could have happened as a result of the displacement of the layers of the earth's crust.
Often, after landslides in mountainous areas, such outcrops of the deposit were exposed, and people got the opportunity to get to pieces of “combustible stone”.
Later, when the first technique appeared, coal began to be developed in an open way. Some coal mines plunged to a depth of more than 300 meters.
Today, thanks to modern technology, people descend to a depth of more than 1000 m, where high-quality coal is mined.

Different types of coal can be used to generate heat. When burned, it releases much more than can be obtained from wood or other solid fuels. The hottest grades of coal are used in metallurgy, where high temperatures are needed.
In addition, coal is a valuable raw material for the chemical industry. A lot of necessary and useful substances are extracted from it.

We hope that the information provided coal helped you. And you can leave your report about coal through the comment form.

For almost 200 years, humanity has been using reserves that have been formed for hundreds of millions of years. Such wastefulness will someday lead us to collapse and an energy crisis, until we begin to take better care of our resources. For a better understanding, it would be worth knowing how coal was formed and how many years the proven reserves will last.

The need for energy

All industries need constant source of energy:

Energy is released during the combustion of hydrocarbons. In this regard, oil and gas are irreplaceable resources.
It is possible to obtain the proper amount of energy from nuclear power plants. The splitting of the atom is a promising industry, but a couple of disasters pushed this option into the background for a long time.
Wind, sun and even water currents can provide electricity. With a proper approach to the issue and the construction of modern structures.

Some new and promising industries today almost never develop and humanity is forced to continue to burn coal, smoke the sky and receive crumbs of energy. This state of affairs is beneficial to large corporations that receive huge incomes from the sale of combustible fuels.

Perhaps in the coming decades the situation will change at least a little and promising projects, in terms of alternative energy generation options, will give the green light. So far, one can only hope for the prudence of large investors who will prefer saving from the energy crisis in the future to immediate benefits.

Where did coal come from?

Regarding the formation of coal, there is accepted scientific theory:

Somewhere around 300-400 million years ago, much more organic matter was growing on Earth. It's about plants, giant green plants.
Like all living things, plants died. Bacteria, at that stage, could not cope with the task of completely decomposing these giants.
In the absence of oxygen access, entire layers of compressed and rotting ferns were formed.
Over the passing millions of years, epochs have changed, other formations were layered on top, the original layer lay deeper and deeper.

There is an opinion that gradually all this substance was transformed into peat, which later turned into coal. Such transformations are taking place or may still be taking place, from a theoretical point of view. But only in the presence of already formed peat, there is no longer a sufficient number of plants for the formation of new layers on the Earth. Not that era, not those climatic conditions.

It is worth noting that volume has changed dramatically.. Losses during the transition from peat to coal alone are 90%, and it is still unknown what the initial volume of dead plants was.

Properties of hard coal

All coal properties can be divided into significant for nature and for humans:

But still, the main and most interesting for us is the fact that a sufficient amount of energy is released during the combustion of coal. Approximately 75% of what can be obtained by burning the same volume of oil.

Defenders of nature are concerned about a completely different property - the ability to release carbon dioxide when burned . Burn a kilogram of coal and you get almost 3 kg of carbon dioxide emissions into the atmosphere. The global volume of consumption is already estimated at billions of tons of minerals, so the numbers are not funny at all.

Coal mining

In some countries, coal mines have long been closed:

Low profitability. Today it is much more profitable to pump and sell oil and gas. Less cost, less possible consequences.
High risk of accidents. Disasters at mines are not uncommon in the modern world, even with all precautions.
Almost complete development of existing reserves. If a country started mining as early as the century before last and all the time "fed" from one coal basin, one should not expect much from it in our time.
Availability of an alternative. It's about not only about oil and gas, nuclear energy has also taken its niche. Solar panels, windmills are being introduced, hydroelectric power stations are operating. The process is slow but inevitable.

But someone is still forced to descend into the mine:

Mining occurs at a depth of up to 1 km, as a rule.
The cheapest way is to mine coal no deeper than 100 m, in which case it can be done using an open method.
Shifts of miners equipped with tools and respirators are constantly descending into the face.
The role of manual labor has decreased significantly, most of the work is done by mechanisms.
Despite this, miners are constantly at risk of being buried under rubble and buried in a makeshift common grave.
Constant exposure to dust causes problems with the respiratory tract. Pneumoconiosis officially recognized as an occupational disease.

In some ways such work is compensated by solid salaries and early retirement.

How did coal come about?

It took hundreds of millions of years to form coal.

Here is how the process of its formation on Earth went:

Massively bred plants on the surface, due to favorable climatic conditions.
Gradually they died, and microorganisms did not have time to completely process the remains.
The organic mass formed a whole layer. In some areas, there was no access to oxygen, especially in swampy areas.
Under anaerobic conditions, specific microorganisms continued to take part in the processes of putrefaction.
New layers were layered on top, increasing the pressure.
Thanks to the organic basis big amount carbon, rotting, constant pressure and hundreds of millions of years coal was formed.

This is how scientists see the whole process, based on modern methods of study.

Perhaps this picture will still be amended in the future, time will tell. In the meantime, we can only believe her or voice some of our assumptions. But to be taken seriously, they have to be proven.

It is not necessary to know how coal was formed in order to enjoy all the delights of scientific and technological progress. But for general development worth checking out.

Video about the appearance of coal on Earth

In this video, geologist Leonid Yaroshin will tell you how and where coal was formed, how it is mined and where it is currently used:

Anthracite is the oldest fossil coal, the coal of the highest degree of coalification.

It is characterized by high density and gloss. Contains 95% carbon. It is used as a solid high-calorie fuel (calorific value 6800-8350 kcal/kg).

Coal

Coal- sedimentary rock, which is a product of deep decomposition of plant remains (tree ferns, horsetails and club mosses, as well as the first gymnosperms). Most coal deposits were formed in the Paleozoic, predominantly in the Carboniferous period, approximately 300-350 million years ago.

By chemical composition coal is a mixture of high molecular weight polycyclic aromatic compounds with high mass fraction carbon, as well as water and volatile substances with small amounts of mineral impurities, which form ash when coal is burned. Fossil coals differ from each other in the ratio of their components, which determines their heat of combustion. A number of organic compounds that make up coal have carcinogenic properties. The carbon content in hard coal, depending on its grade, ranges from 75% to 95%.

Brown coal

Brown coal- solid fossil coal, formed from peat, contains 65-70% carbon, has a brown color, the youngest of fossil coals. It is used as a local fuel, as well as a chemical raw material.

coal formation

For the formation of coal, abundant accumulation of plant mass is necessary. In ancient peat bogs, starting from the Devonian period, organic matter accumulated, from which, without access to oxygen, fossil coals were formed. Most commercial fossil coal deposits date from this period, although younger deposits also exist. The age of the most ancient coals is estimated at about 350 million years.

Coal is formed when rotting plant material accumulates faster than it can be bacterially decomposed. An ideal environment for this is created in swamps, where stagnant water, depleted in oxygen, prevents the vital activity of bacteria and thereby protects the plant mass from complete destruction. At a certain stage of the process, the acids released during the process prevent further activities bacteria. This is how peat- the initial product for the formation of coal. If then it is buried under other deposits, then the peat experiences compression and, losing water and gases, is converted into coal.

Under the pressure of layers of sediments 1 km thick, a layer of brown coal 4 meters thick is obtained from a 20-meter layer of peat. If the depth of burial of plant material reaches 3 kilometers, then the same layer of peat will turn into a layer of coal 2 meters thick. At a greater depth, about 6 kilometers, and at a higher temperature, a 20-meter layer of peat becomes a layer of anthracite 1.5 meters thick.

Proved coal reserves

Proved coal reserves for 2006 in million tons

A country	Coal	Brown coal	Total	%
USA	111338	135305	246643	27,1
Russia	49088	107922	157010	17,3
China	62200	52300	114500	12,6
India	90085	2360	92445	10,2
Australian Union	38600	39900	78500	8,6
South Africa	48750	0	48750	5,4
Kazakhstan	28151	3128	31279	3,4
Ukraine	16274	17879	34153	3,8
Poland	14000	0	14000	1,5
Brazil	0	10113	10113	1,1
Germany	183	6556	6739	0,7
Colombia	6230	381	6611	0,7
Canada	3471	3107	6578	0,7
Czech	2094	3458	5552	0,6
Indonesia	740	4228	4968	0,5
Türkiye	278	3908	4186	0,5
Madagascar	198	3159	3357	0,4
Pakistan	0	3050	3050	0,3
Bulgaria	4	2183	2187	0,2
Thailand	0	1354	1354	0,1
North Korea	300	300	600	0,1
New Zealand	33	538	571	0,1
Spain	200	330	530	0,1
Zimbabwe	502	0	502	0,1
Romania	22	472	494	0,1
Venezuela	479	0	479	0,1
Total	478771	430293	909064	100,0

Coal in Russia

Types of coal

In Russia, depending on the stage of metamorphism, they distinguish: brown coal, black coal, anthracite and graphite. Interestingly, in Western countries there is a slightly different classification: respectively, lignites, sub-bituminous coals, bituminous coals, anthracites and graphites.

Brown coals. They contain a lot of water (43%) and therefore have a low calorific value. In addition, they contain a large number of volatile substances (up to 50%). They are formed from dead organic residues under the pressure of the load and under the influence of elevated temperature at depths of the order of 1 kilometer.
Stone coals. They contain up to 12% moisture (3-4% internal), therefore they have a higher calorific value. They contain up to 32% of volatile substances, due to which they ignite well. Formed from brown coal at depths of about 3 kilometers.
Anthracites. Almost entirely (96%) are composed of carbon. They have the highest calorific value, but ignite poorly. They are formed from coal with an increase in pressure and temperature at depths of about 6 kilometers. Mainly used in the chemical industry

History of coal mining in Russia

The formation of the coal industry in Russia dates back to the first quarter of the 19th century, when the main coal basins were already discovered.

The dynamics of fossil coal production in the Russian Empire can be viewed.

Coal reserves in Russia

Russia has 5.5% (why such a difference with the percentage of proven coal reserves for 2006? -because most of it is not suitable for development - Siberia and permafrost) of world coal reserves, which is more than 200 billion tons. Of these, 70% are lignite reserves.

In 2004, 283 million tons of coal were mined in Russia. 76.1 million tons were exported.
In 2005, 298 million tons of coal were mined in Russia. 79.61 million tons were exported.

In Russia in 2004 there was a shortage of coking coal grades Zh and K in the amount of at least 10 million tons (VUHIN estimate), which was due to the retirement of mining facilities in Vorkuta and Kuzbass.

The largest promising deposits

Elga field(Sakha). Belongs to OAO Mechel. The most promising object for open development is located in the southeast of the Republic of Sakha (Yakutia), 415 km east of the city of Neryungri. The deposit area is 246 km². The deposit is a gentle brachysynclinal asymmetric fold. The deposits of the Upper Jurassic and Lower Cretaceous are coal-bearing. The main coal seams are confined to the deposits of the Neryungri (6 seams, 0.7-17 m thick) and Undyktan (18 seams, also 0.7-17 m thick) formations. Most of coal resources are concentrated in four layers y4, y5, n15, n16, usually of a complex structure. The coals are mostly semi-shiny lenticular-banded with a very high content of the most valuable component - vitrinite (78-98%). According to the degree of metamorphism, coals belong to the III (fat) stage. Coal grade Zh, group 2Zh. Coals are medium- and high-ash (15-24%), low-sulfur (0.2%), low-phosphorus (0.01%), good sintering (Y = 28-37 mm), with high calorific value (28 MJ/kg). Elga coal can be enriched to the highest world standards and get export coking coal High Quality. The deposit is represented by thick (up to 17 meters) flat seams with overburden deposits of small thickness (overburden ratio - about 3 cubic meters per ton of raw coal), which is very beneficial for organizing open-pit mining.

Elegest deposit(Tyva) has reserves of about 1 billion tons of coking coal of a scarce brand "Zh" (the total reserves are estimated at 20 billion tons). 80% of the reserves are located in one layer 6.4 m thick (the best mines in Kuzbass work in layers 2-3 m thick, in Vorkuta coal is mined from layers thinner than 1 m). After reaching the design capacity by 2012, Elegest is expected to produce 12 million tons of coal annually. The license for the development of Elegest coal belongs to the Yenisei Industrial Company, which is part of the United Industrial Corporation (OPK). On March 22, 2007, the Government Commission for Investment Projects of the Russian Federation approved the implementation of projects for the construction of the Kyzyl-Kuragino railway line in conjunction with the development of the mineral resource base of the Republic of Tuva.

The largest Russian coal producers

Coal gasification

This direction of coal utilization is associated with its so-called "non-energy" use. We are talking about the processing of coal into other types of fuel (for example, into combustible gas, medium-temperature coke, etc.), preceding or accompanying the production of thermal energy from it. For example, in Germany during the Second World War, coal gasification technologies were actively used for the production of motor fuel. In South Africa, at the SASOL plant, using the technology of layered gasification under pressure, the first developments of which were also carried out in Germany in the 30-40s of the XX century, more than 100 types of products are currently produced from brown coal. (This gasification process is also known as the "Lurgi process".)

In the USSR, coal gasification technologies, in particular, were actively developed at the Research and Design Institute for the Development of the Kansk-Achinsk Coal Basin (KATEKNIIugol) in order to increase the efficiency of the use of Kansk-Achinsk brown coal. The staff of the institute developed a number of unique technologies for processing low-ash brown and black coals. These coals may be susceptible energy technology processing into valuable products such as medium temperature coke, capable of serving as a substitute for classical coke in a number of metallurgical processes, combustible gas, suitable, for example, for combustion in gas boilers as a substitute for natural gas, and synthesis gas, which can be used in the production of synthetic hydrocarbon fuels. The combustion of fuels obtained as a result of energy-technological processing of coal gives a significant gain in terms of harmful emissions relative to the combustion of the original coal.

After the collapse of the USSR, KATEKNIIugol was liquidated, and the institute's employees, who were engaged in the development of coal gasification technologies, created their own enterprise. In 1996, a plant for processing coal into sorbent and combustible gas was built in Krasnoyarsk (Krasnoyarsk Territory, Russia). The plant is based on the patented technology of layered coal gasification with inverted blast (or the reversed process of layered coal gasification). This plant is still in operation. Due to the exceptionally low (compared to traditional coal combustion technologies) indicators of harmful emissions, it is freely located near the city center. Later, on the basis of the same technology, a demonstration plant for the production of household briquettes was also built in Mongolia (2008).

It should be noted some characteristic differences between the technology of layered gasification of coal with reversed blast from the direct gasification process, one of the varieties of which (gasification under pressure) is used at the SASOL plant in South Africa. Combustible gas produced in the inverted process, in contrast to the direct process, does not contain coal pyrolysis products, so complex and expensive gas cleaning systems are not required in the inverted process. In addition, in the inverted process, it is possible to organize incomplete gasification (carbonization) of coal. At the same time, two useful products are produced at once: medium-temperature coke (carbonizate) and combustible gas. The advantage of the direct gasification process, on the other hand, is its higher productivity. During the period of the most active development of coal gasification technologies (the first half of the 20th century), this led to an almost complete lack of interest in the reversed process of layered coal gasification. However, the current market conditions are such that the cost of medium temperature coke alone, produced in the reversed coal gasification (carbonization) process, makes it possible to compensate for all the costs of its production. Associated product - combustible gas suitable for combustion in gas boilers in order to obtain heat and / or electrical energy - in this case, it has a conditionally zero cost. This circumstance provides a high investment attractiveness of this technology.

Another well-known technology for the gasification of brown coal is the energy-technological processing of coal into medium-temperature coke and thermal energy in an installation with a fluidized (fluidized) bed of fuel. An important advantage of this technology is the possibility of its implementation by reconstructing standard coal-fired boilers. At the same time, the performance of the boiler in terms of thermal energy is maintained at the same level. A similar project for the reconstruction of a typical boiler has been implemented, for example, at the Berezovsky open pit (Krasnoyarsk Territory, Russia). In comparison with the technology of layered coal gasification, energy-technological processing of coal into medium-temperature coke in a fluidized bed is characterized by a significantly higher (15-20 times higher) productivity.

It takes a long time to turn peat into coal. Layers of peat gradually accumulated in peat bogs, and overgrown with more and more plants from above. At depth, complex compounds found in decaying plants break down into ever simpler ones. They are partially dissolved and carried away by water, and some of them pass into a gaseous state, forming methane and carbon dioxide. Bacteria and various fungi that inhabit all swamps and peat bogs also play an important role in the formation of coal, as they contribute to the rapid decomposition of plant tissues. Over time, in the process of such changes, carbon begins to accumulate in peat, as the most stable substance. Over time, carbon in peat becomes more and more.

An important condition the accumulation of carbon in peat is the lack of access to oxygen. Otherwise, carbon, having combined with oxygen, would have turned into carbon dioxide and escaped. The layers of peat that turn into coal are first isolated from the air and the oxygen contained in it by the water that covers them, and from above by newly emerging layers of peat from the decaying layer of plants and new thickets growing on them.

Coal stages

The first stage is lignite, loose brown coal, most similar to peat, not ancient origin. The remains of plants, especially wood, are clearly visible in it, since it takes longer to decompose. Lignite is formed in modern peat bogs middle lane, and consists of reeds, sedges, peat moss. The woody peat that forms in the subtropical zone, such as the swamps of Florida in the United States, is very similar to fossil lignite.

Brown coal is created with a stronger decomposition and change in plant residues. Its color is black or dark brown, wood remains are less common in it, and there are no plant remains at all, it is stronger than lignite. When burning, brown coal emits much more heat, since there are more carbon compounds in it. Over time, brown coal turns into bituminous coal, but not always. The transformation process occurs only if a layer of brown coal sinks into deeper layers of the earth's crust when mountain building occurs. To turn brown coal into hard coal or anthracite, you need a very high temperature of the earth's interior and great pressure.

In coal, the remains of plants and wood can only be found under a microscope, it is shiny, heavy and strong almost like a stone. Black and coal called anthracite contains the largest number carbon. This coal is valued above all, since when burned it gives the most heat.