Wood has long been used to heat houses, but in order to constantly maintain combustion it is necessary to add logs again and again. With the development of the coal mining industry, more and more people began to use coal: it gives more heat and burns longer. If the stove is properly installed, a portion of coal poured into the boiler in the evening will maintain a stable temperature all night.

History of the formation of coal and its types

The entire process of coal formation can be divided into two main stages: the formation of peat and the actual process of coalification - the conversion of peat into coal.

Peat formed on vast water-covered areas from plant remains of varying degrees of decomposition. Some plants rotted completely to a gel-like state, while others retained their cellular structure. Their remains accumulated at the bottom of reservoirs, which gradually turned into swamps. Required condition, necessary for the formation of peat, is the absence of oxygen. There was little oxygen under the water column; during the decomposition of the residues, hydrogen sulfide, methane and carbon dioxide were released, which contributed to the hardening of the residues. Peat formed.

But not all peatlands were converted to coal. The carbonization process requires: high pressure, high temperature and a long period of time. Depending on the presence of these conditions, the formation of coal occurred or not. First, the peat was carried over by sedimentary rocks, which increased the pressure and temperature inside the peat layer. Under such conditions, brown coal was formed - the first stage of coalification. In some areas, strata displacement occurred, causing brown coal seams to sink (some of the discovered deposits are at depths of more than 6,000 meters). In some places, these processes were accompanied by the rise of magma and volcanic eruptions. High blood pressure, lack of oxygen and high temperatures contributed to the fact that moisture and natural gases There was less and less brown coal, and more and more carbon. As water and gases were displaced, brown coal turned into bituminous coal, then, in the presence of high temperatures, into anthracite. The main difference between brown coal and hard coal: brown coal contains more moisture and natural gases and less carbon, which affects the amount of heat released during combustion.

Today, the age of coal deposits is determined by plant remains. The oldest ones date back to the Carboniferous period (345-280 million years ago). During this period, most of the coal basins of North America (eastern and central USA), central and western Europe, southern Africa, China, and India were formed. In Eurasia, most of the coal deposits were formed in the Permian period, some of the small coal basins in Europe date back to the Triassic period. The activity of coal formation increases towards the end of the Jurassic and in the Cretaceous. Around this time, deposits were formed in eastern Europe, the American Rocky Mountains, Indochina and central Asia. Later, mainly brown coals and peat deposits were formed.

Types of coal

Coal is classified according to its moisture content, natural gases and carbon content. As the amount of carbon increases, its calorific value increases. The less moisture and volatile substances (gases), the better it tolerates storage and transportation.

Lignite- coal of the first stage of coalification. It differs from brown coal in the smaller amount of water (45%) in its composition and greater heat generation. The structure is fibrous, the color ranges from brown to black (more high quality). Most often used in the energy sector (at thermal power plants), it is rarely used for heating private houses, as it is poorly stored and has a low calorific value in conventional stoves.

Sub-bituminous coal- black color, less pronounced fibrous structure, higher calorific value compared to lignite, lower moisture content (30%). During transportation it crumbles, and outdoors weathered. When burned, it emits 5-6 kW/kg. It is used both in the energy sector and in housing and communal services for heating.

Bituminous coal It has the highest calorific value and does not lose its qualities during transportation and storage. When burning, it releases 7-9 kW/kg of heat. Some of its types are used for coking.

Anthracite- coal is pitch black in color. It has the highest hydrocarbon content. It is difficult to ignite, but it burns for a long time and without soot, emits large number heat (more than 9 kW/kg). It is anthracite that is most often used for heating.

What kind of coal is used for heating?

In Russia and the CIS countries there is a system adopted back in 1988. Coal is classified according to GOST 25543-88, which is divided into 7 categories. Only some are used for heating:

Long flame coal (D). It got its name due to the long combustion process with the release of a large amount of heat (5600-5800 kcal/kg). No special airflow is required for its ignition and combustion, which is why long-flame coals are often used in domestic boilers on solid fuel. Depending on the size it happens:

• WPC - large slab - piece sizes 50-200 mm;
• DPKO - slab fist-nut - piece sizes 25-100 mm;
• PO - walnut - 26-50 mm;
• DM - small - sizes 13-25 mm;
• DS - seed - 6-13 mm;
• DR - private - no standard sizes.

Long-flame coal is optimal for heating: the flame is long (similar to firewood), it produces a lot of heat, ignites and burns easily - enough for normal combustion natural traction. Its relatively low cost combined with excellent characteristics and determined the popularity of this brand of coal. It is purchased not only for heating private houses, but also for boiler houses, educational and medical institutions. Moreover, fuel of any fraction is used: from large “K” to small “M”.

Long-flame gas (LG). It differs from brand D in having a higher calorific value. All fractions are used for heating private houses: from “large” to “ordinary”. More demanding than long-flame in terms of storage conditions, because weathers more intensively.

Anthracite (A). It emits a lot of body, has a low ash content (ash residue 10%), burns long and evenly, the smoke when burning is white (all other brands “give” black smoke). Despite high performance It cannot be definitely recommended for heating private houses: anthracite has a high cost and is difficult to light.

In some cases, they buy lean coals “T”, fatty “Zh” or low-caking “SS”. The remaining classes have predominantly industrial use. They are used in the energy and metallurgy industries, some grades are used for coking and beneficiation. When choosing coal, you need to pay attention not only to its characteristics, but also to the cost of delivery. If your area does not sell long flame or anthracite, then most likely you will have to make do with what is on the market. You should also pay attention to the recommendations of the manufacturers of your boiler: the documents usually indicate the brands for which the equipment was designed. They should be used.

To increase comfort and to save money, many people prefer to have several fractions: it is more convenient to melt with the “walnut” or “large” fraction, and long burning pour in the “seed”. For the coldest periods, a certain amount of anthracite is stored, which, although difficult to ignite, burns long and hot in a heated boiler.

Coking and enriched coals pass special treatment to increase calorific value. These types are used in metallurgy and energy. This fuel is not suitable for domestic boilers: due to excessively high combustion temperatures, the stove may burst.

If you listen to people with experience, they say that the best effect is achieved by the following sequence of pouring fuel into the boiler: melt it with a long flame, then add anthracite fraction of the “nut” - it burns for a long time, it gives a lot of heat, and at night add “seeds” to the stove, which will burn until the morning.

A different procedure for lighting brick stoves is recommended: light the stove with wood, when it gets hot, fill it with “seeds” or (open the vent and damper for better oxygen supply). If there is a lot of dust in the seed, you can moisten it with water - this will make it flare up easier. When the heat in the oven is sufficient, you can use the “fist”.

What is charcoal and what is it used for?

Charcoal has been used by people for many thousands of years: it was found during excavations in settlements cavemen. It is unlikely that they made it themselves; rather, they collected it from fires or saved the remains of fires, but, apparently, they knew about its properties and knew how to use it.

Today in our country this type of fuel is used mostly for cooking: it is used in barbecues and barbecues, and added to fires. Sometimes used for fireplaces: it burns for a long time, produces a lot of heat (7800 KC/kg), and produces almost no smoke or soot. The remaining ash is an excellent fertilizer and is used to fertilize forest lands or agricultural fields. Charcoal ash is also used to produce fertilizers.

In industry charcoal used for smelting cast iron. To produce a ton of alloy, only 0.5 tons of this fuel is required. At the same time, cast iron receives increased durability to corrosion and strength. Coal is used as a flux in the smelting of brass, bronze, copper, manganese, zinc and nickel. It is used to make solid lubricants for mechanical engineering, used for grinding in instrument making and printing, etc. Filters for various purposes are made from charcoal.

Today, charcoal is beginning to be considered as an alternative to traditional fuel: unlike coal, oil and gas, it is a renewable material. Moreover, modern technologies make it possible to obtain charcoal even from industrial waste: from sawdust, dust, bushes, etc. Briquettes are formed from such crushed raw materials, which provide 1.5 times more heat than ordinary charcoal. In this case, heat is released over a longer period of time and the heat is uniform.

How to make charcoal

Until the 20th century, charcoal was produced by burning wood or specially shaped piles. Wood was placed in them, covered with earth, and set on fire through special holes made. This technology is generally available and is still used in some countries today. But it has low efficiency: 1 kg of coal takes up to 12 kg of wood, and it is also impossible to control the quality of the resulting charcoal. The next stage in the development of charcoal burning was the use of pipes in earth furnaces. This improvement increased the efficiency of the process: 8 kg of wood was used per kilogram.

In modern charcoal burning devices, 3-4 kg of raw materials are consumed per kilogram of product. At the same time, much attention is paid to the environmental friendliness of the process: during the production of charcoal, a lot of smoke, soot and harmful gases are released into the atmosphere. Modern installations The released gases are captured and sent to special chambers, where they are used to heat the furnace to the coking temperature.

The conversion of wood to charcoal occurs in an oxygen-free atmosphere at high temperature(pyrolysis reaction). The whole process is divided into three stages:

• at 150 o C, moisture is removed from the wood;
• at 150-350 o C, the release of gases and the formation of organic products;
• at 350-550 o C, resins and non-condensable gases are separated.

According to GOST, charcoal is divided into several grades depending on the type of wood used:

• • A - hardwood;
  • B - hard and soft deciduous, conifers(O ).

Brands B and C are most often charcoal briquettes, which are produced using waste from wood processing plants. This great view biofuel, which has long been used in Europe for heating and even in power plants: during their combustion, no sulfur compounds are formed (there is no sulfur in charcoal), and hydrocarbons are contained in minimal quantities. Using the technology of your ancestors, you can burn coal for your own needs yourself. .

Anthracite is the oldest of fossil coals, the coal with the highest degree of carbonization.

Characterized by high density and shine. 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 mosses, as well as the first gymnosperms). Most coal deposits were formed during the Paleozoic, predominantly 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 burning coal. Fossil coals differ from each other in the ratio of their constituent components, which determines their calorific value. Row organic compounds, which are part of coal, have carcinogenic properties. The carbon content of coal, depending on its type, ranges from 75% to 95%.

Brown coal

Brown coal- hard 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 and also as a chemical raw material.

Coal formation

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

Coal is formed when decaying plant material accumulates faster than bacterial decomposition occurs. The ideal environment for this is created in swamps, where stagnant water, depleted of oxygen, prevents the 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 bacterial activity. This is how it arises peat- the initial product for the formation of coal. If it is then buried under other sediments, the peat experiences compression and, losing water and gases, is converted into coal.

Under the pressure of sediment layers 1 kilometer thick, a 20-meter layer of peat produces a layer of brown coal 4 meters thick. 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 greater depths, about 6 kilometers, and at higher temperatures, a 20-meter layer of peat becomes a layer of anthracite 1.5 meters thick.

Proven coal reserves

Proven coal reserves for 2006 in million tons

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
Commonwealth of Australia	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 Republic	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 coals, bituminous coals, anthracites and graphites. Interestingly, in Western countries there is a slightly different classification: respectively, lignites, subbituminous coals, bituminous coals, anthracites and graphites.

1. Brown coals. They contain a lot of water (43%) and therefore have a low calorific value. In addition, they contain a large amount of volatile substances (up to 50%). They are formed from dead organic residues under load pressure and under the influence of elevated temperature at depths of about 1 kilometer.
2. Stone coals. They contain up to 12% moisture (3-4% internal), therefore they have a higher calorific value. They contain up to 32% volatile substances, due to which they ignite well. They are formed from brown coal at depths of about 3 kilometers.
3. Anthracites. Almost entirely (96%) consists of carbon. They have the highest heat of combustion, but do not ignite well. They are formed from coal when pressure and temperature increase 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 had already been discovered.

Dynamics of fossil coal production volumes in Russian Empire you can see .

Coal reserves in Russia

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

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

In Russia in 2004, there was a shortage of coking coal grades “Zh” and “K” of at least 10 million tons (VUKHIN estimate), which was associated with the retirement of mining capacities in Vorkuta and Kuzbass.

Largest promising deposits

Elginskoye field(Sakha). Owned by Mechel OJSC. The most promising object for open-pit mining is located in the southeast of the Republic of Sakha (Yakutia), 415 km east of the city of Neryungri. The field area is 246 km². The deposit is a gently sloping brachysynclinal asymmetrical fold. The deposits of the Upper Jurassic and Lower Cretaceous are carbon-bearing. The main coal seams are confined to the deposits of the Neryungri (6 seams with a thickness of 0.7-17 m) and Undyktan (18 seams with a thickness of also 0.7-17 m) formations. Most of the coal resources are concentrated in four seams y4, y5, n15, n16, usually of 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%), well-caking (Y = 28-37 mm), with a high calorific value (28 MJ/kg). Elga coal can be enriched to the highest world standards and produce high-quality export coking coal. The deposit is represented by thick (up to 17 meters) gently sloping seams with overlying deposits of low thickness (the stripping ratio is about 3 cubic meters per ton of raw coal), which is very beneficial for organizing mining open method.

Elegestskoye field(Tuva) has reserves of about 1 billion tons of coking coal of the scarce grade “Zh” (the total volume of reserves is estimated at 20 billion tons). 80% of the reserves are located in one seam 6.4 m thick (the best mines in Kuzbass work in seams 2-3 m thick, in Vorkuta coal is mined from seams thinner than 1 m). After reaching its design capacity by 2012, Elegest is expected to produce 12 million tons of coal annually. The license to develop Elegest coals belongs to the Yenisei Industrial Company, which is part of the United Industrial Corporation (UPK). Government Commission on investment projects On March 22, 2007, 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 to produce motor fuel. In South Africa, at the SASOL plant, using layered gasification technology under pressure, the first developments of which were also carried out in Germany in the 30-40s of the 20th 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 coals. The Institute's staff have developed a number of unique technologies for processing low-ash brown and hard coals. These coals may be subject to energy technology processing into such valuable products as medium temperature coke, capable of serving as a substitute for classic coke in a number of metallurgical processes, flammable 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. Combustion of fuels obtained as a result of energy-technological processing of coal provides a significant gain in terms of harmful emissions relative to the combustion of original coal.

After the collapse of the USSR, KATEKNIIugol was liquidated, and the institute’s employees involved in the development of coal gasification technologies created their own enterprise. In 1996, a plant for processing coal into sorbent and flammable gas was built in Krasnoyarsk (Krasnoyarsk Territory, Russia). The plant is based on a patented technology of layered coal gasification with reverse blast (or reverse process of layered coal gasification). This plant is still operating today. Due to the exceptionally low (compared to traditional technologies combustion of coal) indicators of harmful emissions, it is freely located near the city center. Subsequently, based on 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 coal gasification with reverse blast and direct process gasification, one of the varieties of which (gasification under pressure) is used at the SASOL plant in South Africa. The combustible gas produced in the reverse process, unlike the direct process, does not contain coal pyrolysis products, therefore, complex and expensive gas purification systems are not required in the reverse process. In addition, in the reverse process it is possible to organize incomplete gasification (carbonization) of coal. In this case, two are produced at once useful product: medium temperature coke (carbonate) and combustible gas. The advantage of the direct gasification process, on the other hand, is that it is more high performance. During the most active development coal gasification technologies (the first half of the 20th century), this led to an almost complete lack of interest in the reverse process of layered coal gasification. However, at present, market conditions are such that the cost of medium-temperature coke alone, produced in the reverse process of coal gasification (carbonization), makes it possible to compensate for all the costs of its production. By-product is a flammable gas suitable for combustion in gas boilers to obtain thermal and/or electrical energy, - in this case has a conditionally zero cost. This circumstance provides high investment attractiveness 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 (boiling) bed of fuel. An important advantage of this technology is the possibility of its implementation by reconstructing standard coal boilers. At the same time, the boiler’s thermal energy performance remains at the same level. A similar project for the reconstruction of a standard boiler was implemented, for example, at the Berezovsky open-pit mine (Krasnoyarsk Territory, Russia). In comparison with the layered coal gasification technology, the energy-technological processing of coal into medium-temperature coke in a fluidized bed is characterized by significantly higher (15-20 times higher) productivity.

1. Chemical properties of coal

2. Classification of coal

3. Formation of coal

4. Coal reserves

Coal is sedimentary rock, representing deep decomposition of plant remains (tree ferns, horsetails and mosses, as well as the first gymnosperms).

Chemical properties of coal

By chemical composition coal It is a mixture of high molecular weight aromatic compounds with a high mass fraction of carbon, as well as water and volatile substances with small amounts of mineral impurities. Such impurities form ash when burning coal. Fossil coals differ from each other in the ratio of their constituent components, which determines their calorific value. A number of organic compounds that make up coal have carcinogenic properties.

Most coal deposits were formed in the Paleozoic, mainly during the Carboniferous period, approximately 300-350 million years ago. By chemical composition coal It is a mixture of high molecular weight polycyclic aromatic compounds with a high mass fraction of carbon, as well as water and volatile substances with small amounts of mineral impurities, which form ash when burning coal. Fossil coals differ from each other in the ratio of their constituent components, which determines their calorific value. A number of organic compounds that make up coal have carcinogenic properties. The carbon content of coal, depending on its type, ranges from 75% to 95%.

Coal, solid fuel minerals plant origin; a type of fossil coal with a higher carbon content and greater density than brown coal. It is a dense rock of black, sometimes gray-black color with a shiny, semi-matte or matte surface. Contains 75-97% or more carbon; 1.5-5.7% hydrogen; 1.5-15% oxygen; 0.5-4% sulfur; up to 1.5% nitrogen; 45-2% volatiles; the amount of moisture ranges from 4 to 14%; ash - usually from 2-4% to 45%. The highest calorific value, calculated for the wet ash-free mass of coal, is not less than 23.8 MJ/kg (5700 kcal/kg).

Coal is the remains of plants that died many millions of years ago, the decay of which was interrupted as a result of the cessation of air supply. Therefore, they could not release the carbon taken from it into the atmosphere. Air access ceased especially abruptly where swamps and swampy forests sank as a result of tectonic movements and changes climatic conditions and were covered with other substances on top. At the same time, plant remains were transformed under the influence of bacteria and fungi (coalified) into peat and further into brown coal, hard coal, anthracite and graphite.

Based on the composition of the main component - organic matter, coals are divided into three genetic groups: humolites, sapropelites, saprohumolites. Humolites predominate, the starting material of which was the remains of higher land plants. Their deposition occurred mainly in swamps that occupied the low-lying coasts of seas, bays, lagoons, and freshwater basins. As a result of biochemical decomposition, the accumulating plant material was processed into peat, with a significant influence on water content and chemical composition. aquatic environment. The carbon content of hard coal ranges from 75 to 90 percent. The exact composition is determined by the location and conditions of coal conversion. Mineral impurities are either in a finely dispersed state in the organic mass, or in the form of thin layers and lenses, as well as crystals and concretions. The source of mineral impurities in fossil coals can be inorganic parts of coal-forming plants, mineral new formations that precipitate from water solutions circulating in peat bogs, etc.

As a result of prolonged exposure to elevated temperatures and pressure, brown coals are transformed into hard coals, and the latter into anthracite. Irreversible gradual change The chemical composition, physical and technological properties of organic matter at the stage of transformation from brown coals to anthracites is called coal metamorphism.

The structural and molecular rearrangement of organic matter during metamorphism is accompanied by a consistent increase in the relative carbon content in coal, a decrease in the oxygen content, and the release of volatile substances; the hydrogen content, calorific value, hardness, density, fragility, optics, electricity, etc. change. physical properties. Hard coals at the middle stages of metamorphism acquire sintering properties - the ability of gelified and lipoid components of organic matter to transform when heated under certain conditions into a plastic state and form a porous monolith - coke. In zones of aeration and active action of groundwater near the Earth's surface, coals undergo oxidation.

In its effect on the chemical composition and physical properties, oxidation has the opposite direction compared to metamorphism:

coal loses its strength properties and sinterability;

the relative content of oxygen in it increases, the amount of carbon decreases, humidity and ash content increases, and the heat of combustion sharply decreases.

The depth of oxidation of fossil coals depending on modern and ancient relief, mirror positions groundwater, the nature of climatic conditions, material composition and metamorphism ranges from 0 to 100 meters vertically.

The specific gravity of coal is 1.2 - 1.5 g/cm3, calorific value is 35,000 kJ/kg. Hard coal is considered suitable for technological use if, after combustion, the ash content is 30% or less. Primitive mining of fossil coals has been known since ancient times (Greece). Coal began to play a significant role as a fuel in Britain in the 17th century. The formation of the coal industry is associated with the use of coal as coke in the smelting of cast iron. Since the 19th century, transport has been a major purchaser of coal. The main areas of industrial use of coal: production of electricity, metallurgical coke, combustion for energy purposes, production of various (up to 300 items) products through chemical processing. The consumption of coals for the production of high-carbon carbon-graphite materials is increasing. construction materials, rock wax, plastics, synthetic, liquid and gaseous high-calorie fuels, aromatic products by hydrogenation, high nitrous acids for fertilizers. Coke obtained from coal is required in large quantities for metallurgical industry.

Coke is produced at coke plants. Coal is subjected to dry distillation (coking) by heating in special coke ovens without air access to a temperature of C. This produces coke - a solid porous substance. In addition to coke, dry distillation of coal also produces volatile products, which, when cooled to 25-75 C, form coal tar, ammonia water and gaseous products. Coal tar undergoes fractional distillation, resulting in several fractions:

light oil (boiling point up to 170 C) it contains aromatic hydrocarbons (benzene, toluene, acids and other substances;

medium oil (boiling point 170-230 C). These are phenols, naphthalene;

heavy oil (boiling point 230-270 C). These are naphthalene and its homologues

anthracene oil - anthracene, phenathrene, etc.

The composition of gaseous products (coke oven gas) includes benzene, toluene, xyols, phenol, ammonia and other substances. After purification from ammonia, hydrogen sulfide and cyanide compounds, crude benzene is extracted from coke oven gas, from which individual hydrocarbons and a number of other valuable substances are isolated.

Amorphous carbon in the form of coal, as well as many carbon compounds, plays vital role V modern life as sources of receipt various types energy. When coal burns, it releases heat, which is used for heating, cooking and many other things. production processes. Most of the heat received is converted into other types of energy and spent on performing mechanical work.

Coal is a solid fuel, a mineral of plant origin. It is a dense rock of black, sometimes dark gray color with a shiny matte surface. Contains 75-97% carbon, 1.5-5.7% hydrogen, 1.5-15% oxygen, 0.5-4% sulfur, up to 1.5% nitrogen, 2-45% volatiles, the amount of moisture ranges from 4 to 14%. The highest calorific value calculated for the wet ash-free mass of coal is not less than 238 MJ/kg.

Coal is formed from the decomposition products of organic substances of higher plants that have undergone changes under pressure conditions of various rocks earth's crust and under the influence of temperature. With an increase in the degree of metamorphism in the combustible mass, coal increases the carbon content and at the same time reduces the amount of oxygen, hydrogen, and volatile substances. The heat of combustion of coal also changes.

Characteristic physical properties of coal:

density (g/cm3) - 1.28-1.53;

mechanical strength (kg/cm2) - 40-300;

specific heat capacity C (Kcal/g deg) - 026-032;

light refractive index - 1.82-2.04.

The largest coal deposits in the world in terms of production volume are the Tunguska, Kuznetsk, and Pechora basins - in Russian Federation; Karaganda - in Kazakhstan; Appalachian and Pennsylvania basins - in the USA; Ruhrsky - in the Republic of Germany; Great Yellow River - in China; South Wales - in England; Valenciennes - in France, etc.

The uses of coal are varied. It is used as household, energy fuel, metallurgical and chemical industry, as well as for extracting rare and trace elements from it. Coal, coke, and heavy industries process coal using the coking method. Coking is an industrial method of processing coal by heating to 950-1050 C without air access. The main coke-chemical products are: coke oven gas, products from the processing of crude benzene, coal tar, and ammonia.

Hydrocarbons are removed from coke oven gas by washing in scrubbers with liquid absorption oils. After distillation from the oil, distillation from the fraction, purification and repeated rectification, pure commercial products are obtained, such as benzene, toluene, xylenes, etc. From the unsaturated compounds contained in crude benzene, coumarone resins are obtained, which are used for the production of varnishes, paints, linoleum and rubber industry. Cyclopentadiene, which is also obtained from coal, is also a promising raw material. Coal - raw materials for the production of naphthalene and other individual aromatic hydrocarbons. The most important processing products are pyridine bases and phenols.

Through processing, a total of more than 400 different products can be obtained, the cost of which, compared to cost coal itself, increases by 20-25 times, and by-products obtained at coke plants exceed price the coke itself.

The combustion (hydrogenation) of coal to form liquid fuel is very promising. To produce 1t of black gold, 2-3t of coal is consumed. Artificial graphite is obtained from coal. They are used as inorganic raw materials. When processing coal from it into industrial scale vanadium, germanium, sulfur, gallium, molybdenum, and lead are extracted. Ash from coal combustion, mining and processing wastes are used in the production of building materials, ceramics, refractory raw materials, alumina, and abrasives. In order to optimally use coal, it is enriched (removing mineral impurities).

Coal contains up to 97% carbon; it can be said to be the basis of all hydrocarbons, i.e. They are based on carbon atoms. Often we encounter amorphous carbon in the form of coal. In structure, amorphous carbon is the same as graphite, but in a state of extremely fine grinding. Practical Application amorphous forms of carbon are varied. Coke and coal - as a reducing agent in metallurgy for iron smelting.

Classification of coal

Coal is formed from the decomposition products of organic remains of higher plants that have undergone changes (metamorphism) under conditions of pressure from the surrounding rocks of the earth's crust and relatively high temperatures. With an increase in the degree of metamorphism in the combustible mass of coal, the carbon content consistently increases and at the same time the amount of oxygen, hydrogen, and volatile substances decreases; The heat of combustion, the ability to sinter and other properties also change. The industrial classification adopted in the USSR is based on changes in these qualities, determined by the results of thermal decomposition of coal (yield of volatile substances, characteristics of non-volatile residue).

Coal by grade:

long flame (D),

gas (G),

gas fatty (GZh),

fatty (F),

coke fatty (QF),

coke (K),

lean sintering (OS),

skinny (T),

low-caking (SS),

semi-anthracite (PA)

anthracite (A).

Sometimes anthracites are released in separate group. For coking, mainly coal of grades G, Zh, K and OS, partially D and T are used. As coal passes from grade D to grades T-A, the moisture in the working fuel decreases from 14% for grade D to 4 .5-5.0% for brands T-A; reducing the oxygen content (in the combustible mass) from 15% to 1.5%; hydrogen - from 5.7% to 1.5%; content sulfur, nitrogen and ash does not depend on belonging to one brand or another. The heat of combustion of the combustible mass of hard coal consistently increases from 32.4 MJ/kg (7750 kcal/kg) for grade D to 36.2–36.6 MJ/kg (8650–8750 kcal/kg) for grade K and decreases to 35 .4–33.5 MJ/kg (8450–8000 kcal/kg) for PA and A brands.

Based on the size of the pieces obtained during mining, coal is classified into:

slab (P) - more than 100 mm,

large (K) - 50-100 mm,

nut (O) - 26-50 mm,

small (M) - 13-25 mm,

seed (C) - 6-13 mm,

piece (W) - less than 6 mm,

private (P) - not limited by size.

The brand and size of the pieces of coal are indicated by letter combinations - DK, etc.

The classification of hard coal in a number of Western European countries is based on approximately the same principles as in the USSR. IN USA The most common classification of hard coal is based on the yield of volatile substances and heat of combustion, according to which they are divided into subbituminous with a high yield of volatile substances (corresponding to Soviet grades D and G), bituminous with an average yield of volatile substances (corresponding to grades PZh and K), bituminous with a low yield of volatile substances (OS and T) and anthracite coals, divided into semi-anthracites (partially T and A), anthracites themselves and meta-anthracites (A). In addition, there is international classification coal, based on the content of volatile substances, caking, coking and displaying technological properties coals.

Formation of coal

The formation of coal is characteristic of all geological systems from the Silurian and Devonian; coal is very widely distributed in the deposits of the Carboniferous, Permian and Jurassic systems. Coal occurs in the form of layers of varying thickness (from fractions of a meter to several tens of meters or more). The depth of occurrence of coals varies - from reaching the surface to 2000-2500 m and deeper. With the modern level of mining technology, coal can be mined by opencast mining to a depth of 350 m.

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

Coal is formed when decaying plant material accumulates faster than bacterial decomposition occurs. An ideal environment for this is created in swamps, where stagnant water, depleted of oxygen, prevents the activity of bacteria and thereby protects the plant mass from complete destruction. At a certain stage process The acids released during this process prevent further bacterial activity. This is how peat arises - the original product for the formation of coal. If it is then buried under other sediments, the peat experiences compression and, losing water and gases, is converted into coal.

Under the pressure of a sediment layer 1 kilometer thick, a 20-meter layer of peat produces a layer of brown coal 4 meters thick. 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 greater depths, about 6 kilometers, and at higher temperatures, a 20-meter layer of peat becomes a layer of anthracite 1.5 meters thick.

The method of coal mining depends on the depth of its occurrence. Mining is carried out by open-pit mining if the depth of the coal seam does not exceed 100 meters. There are also frequent cases when, with an ever deeper deepening of a coal quarry, it is further profitable to develop the coal deposit underground method. Mines are used to extract coal from great depths. The deepest mines in the territory Russia Coal is mined from a level of just over 1200 meters.

Coal-bearing deposits, along with coal, contain many types of georesources that have consumer significance. These include host rocks such as raw materials for the construction industry, groundwater, coal bed methane, rare and trace elements, including valuable metals and their compounds. For example, some coals are enriched with germanium.

Coal reserves

General geological reserves of hard coal in the USSR are about 4,700 billion tons (according to 1968 estimates), including by grade (in billion tons): D - 1,719; D—G—331; G - 475; GZh - 69.4; F - 156; QOL - 21.5; K - 105; OS - 88.2; SS - 634; T - 205; T-A - 540; PA, A - 139.

The largest reserves of coal in the USSR are located in the Tunguska basin. The largest developed coal basins in the USSR are Donetsk, Kuznetsk, Pechora, Karaganda; V USA- Appalachian and Pennsylvanian, in Poland - Upper Silesian and its continuation in Czechoslovakia - Ostrava-Karvinsky, in Germany— Ruhrsky, in China- Big Huanghebass, in England— South Wales, in France- Valenciennes and in Belgium - Brabant. The uses of coal are varied.

It is used as a household, energy fuel, raw material for the metallurgical and chemical industries, as well as for extracting rare and trace elements from it.

For two decades in a row, coal was in the shadow of the oil boom. Mountains of unsaleable coal rose into the sky. Numerous mines were closed, hundreds of thousands of miners lost their jobs. The Appalachian region of the United States, once a thriving coal basin, has become one of the world's darkest disaster areas. A chaotic transition, under pressure from monopolists, to cheap, imported food - mainly from the Middle East - oil condemned coal to the role of “Cinderella”, deprived of a future. However, this did not happen in some countries, including in the former USSR, which took into account the advantages of an energy structure based on national resources.

Coal reserves are scattered throughout the world. Most industrial countries they are not deprived. The earth is surrounded by two rich coal zones. One stretches across countries former USSR, through China, North America to Central Europe. The other, narrower and less rich, comes from Southern Brazil through South Africa to Eastern Australia.

The most significant deposits hard coal are located in the countries of the former USSR, the USA and China. Coal dominates in western Europe. The main coal basins in Eurasia: South Wales, Valenciennes-Liège, Saar-Lotarginsky, Ruhrsky, Asturian, Kizelovsky, Donetsk, Taimyrsky, Tungussky, South Yakutsky, Funshunsky; in Africa: Jerada, Abadla, Enugu, Huanqui, Witbank; in Australia: Great Syncline, New South Wales; V North America: Green River, Junnta, San Juan River, Western, Illinois, Appalachian, Sabinas, Texas, Pennsylvania; in the burning continent: Carare, Junin, Santa Catarina, Concepcion. In Ukraine, the Lviv-Volyn basin and the Donbass, rich in deposits, should be noted.

Sources

bse.sci-lib.com/ Great Soviet Encyclopedia

ru.wikipedia.org Wikipedia - the free encyclopedia

www.bankreferatov.ru abstracts

dic.academic.ru Dictionaries and encyclopedias on Academician

geography.kz Geography

www.bibliotekar.ru Librarian

poddoni.com/ PalletEk

Investor Encyclopedia. 2013 .

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Coal- Coal Coal was the first fossil fuel used by humans. It enabled the industrial revolution, which in turn contributed to the development of the coal industry, providing it with more modern technology. In 1960... ... Wikipedia

"How coal was formed" short message The information contained in this article will help you prepare for the lesson and expand your knowledge on this topic.

The message “How coal was formed”

Coal is an irreplaceable, exhaustible solid mineral used by humans to generate heat during its combustion. It belongs to the sedimentary rocks.

What is needed to form coal?

Firstly, a lot of time. When peat is formed from plants at the bottom of swamps, chemical compounds arise: the plants disintegrate, partially dissolve, or turn into methane and carbon dioxide.

Secondly, all kinds of fungi and bacteria. Thanks to them, plant tissue decomposes. Peat begins to accumulate a persistent substance called carbon, which becomes more and more over time.

Thirdly, lack of oxygen. If it accumulated in peat, then coal would not be able to form and would simply evaporate.

How is coal formed in nature?

Coal deposits were formed from huge amount plant mass. Ideal conditions are when all these plants accumulated in one place and did not have time to completely decompose. Swamps are ideally suited for this process: the water is poor in oxygen and therefore the vital activity of bacteria is suspended.

After the plant mass has accumulated in the swamps, before it has time to completely rot, it is compressed by soil sediments. This is how the starting material of coal – peat – is formed. Layers of soil seal it in the ground without access to oxygen and water. Over time, the peat turns into a seam of coal. This process is long-term - a significant part of the coal reserves was formed more than 300 million years ago.

And the longer the coal lies in the layers of the earth, the more the fossil is exposed to the action and pressure of deep heat. In swamps where peat accumulates, the water carries sand, clay and dissolved substances, which are deposited in the coal. These impurities form layers in the mineral, dividing it into layers. When coal is cleaned, all that remains is ash.

There are several types of coal - hard coal, brown coal, lignite, boghead, anthracite. Today there are 3.6 thousand coal basins in the world, which occupy 15% of the earth's land. The largest percentage of the world's fossil reserves belongs to the United States (23%), followed by Russia (13%), and third by China (11%).

We hope that the report “How coal was formed” helped you prepare for the lesson. You can add to the message on the topic “How coal was formed” through the comment form.

A ghost town without coal. This was the Japanese Hashima. In the 1930s it was recognized as the most densely populated.

5,000 people fit on a tiny piece of land. They all worked in coal production.

The island turned out to be literally made of a stone source of energy. However, by the 1970s, coal reserves were depleted.

Everyone left. All that remained was the dug up island and the buildings on it. Tourists and Japanese call Hashima a ghost.

The island clearly shows the importance of coal and the inability of humanity to live without it. There is no alternative.

There are only attempts to find her. Therefore, let's pay attention to the modern hero, and not to the vague prospects.

Description and properties of coal

Coal- This rock organic origin. This means that the stone is formed from the decomposed remains of plants and animals.

In order for them to form a dense thickness, constant accumulation and compaction is required. Suitable conditions at the bottom of reservoirs.

Where there is coal deposits, once there were seas and lakes. Dead organisms sank to the bottom and were pressed down by the water column.

This is how it was formed peat. Coal- a consequence of its further compression under pressure not only of water, but also of new layers of organic matter.

Basic coal reserves belong to the Paleozoic era. 280,000,000 years have passed since its end.

This is the era of giant plants and dinosaurs, an abundance of life on the planet. It is not surprising that it was then that organic deposits accumulated especially actively.

Most often, coal was formed in swamps. Their waters have little oxygen, which prevents the complete decomposition of organic matter.

Externally coal deposits resemble burnt wood. The chemical composition of the rock is a mixture of high-molecular carbon aromatic compounds and volatile substances with water.

Mineral impurities are insignificant. The ratio of components is not stable.

Depending on the predominance of certain elements, they distinguish types of coal. The main ones include brown and anthracite.

Buraya a type of coal is saturated with water, and therefore has a low calorific value.

It turns out that the rock is not suitable as fuel, as stone. And brown coal found another use. Which?

This will be given special attention. In the meantime, let’s figure out why water-saturated rock is called brown. The reason is the color.

The coal is brownish, without, friable. From a geological point of view, the mass can be called young. That is, the “fermentation” processes in it are not completed.

Therefore, the stone has a low density and during combustion a lot of volatile substances are formed.

Fossil coal anthracite type - fully formed. It is denser, harder, blacker, shiny.

It takes 40,000,000 years for brown rock to become this way. Anthracite contains a high proportion of carbon – about 98%.

Naturally, the heat transfer of black coal is high, which means that the stone can be used as fuel.

The brown species in this role is used only for heating private houses. They don't need record energy levels.

All that is needed is ease of handling fuel, and anthracite is problematic in this regard. Lighting coal is not easy.

Manufacturers and railway workers got used to it. The labor costs are worth it, because anthracite is not only energy-intensive, but also does not sinter.

Hard coal - fuel, the combustion of which leaves ash. What is it made of if organic matter turns into energy?

Remember the note about mineral impurities? It is the inorganic component of the stone that remains at the bottom.

A lot of ash remains in the Chinese deposit in Liuhuangou province. Anthracite deposits burned there for almost 130 years.

The fire was extinguished only in 2004. Every year 2,000,000 tons of rock were burned.

So do the math how much coal wasted. The raw materials could be useful not only as fuel.

Application of coal

Coal is called solar energy encased in stone. Energy can be transformed. It doesn't have to be thermal.

The energy obtained from burning rock is converted, for example, into electricity.

Coal combustion temperature the brown type almost reaches 2,000 degrees. To obtain electricity from anthracite, it will take about 3,000 Celsius.

If we talk about the fuel role of coal, it is used not only in its pure form.

In laboratories, they learned to obtain liquid and gaseous fuel, and metallurgical plants have been using coke for a long time.

It is obtained by heating coal to 1,100 degrees without oxygen. Coke is a smokeless fuel.

The possibility of using briquettes as ore reducers is also important for metallurgists. Thus, coke comes in handy when casting iron.

Coke is also used as a blending agent. This is the name given to the mixture of initial elements of the future.

Being loosened by coke, the charge is easier to melt. By the way, some components are also obtained from anthracite.

It may contain germanium and gallium as impurities - rare metals that are rarely found anywhere else.

Buy coal strive, in the same way, for production composite materials carbon-graphite type.

Composites are masses made of several components, with a clear boundary between them.

Artificially created materials are used, for example, in aviation. Here, composites increase the strength of parts.

Carbon masses can withstand both very high and low temperatures, are used in catenary support racks.

In general, composites have become firmly established in all areas of life. Railway workers are laying them on new platforms.

Supports are made from nanomodified raw materials building structures. In medicine, composites are used to fill chips in bones and other damage that cannot be replaced with metal prosthetics. Here what kind of coal multifaceted and multifunctional.

Chemists have developed a method for producing plastics from coal. At the same time, waste does not disappear. The low-grade fraction is pressed into briquettes.

They serve as fuel, which is suitable for both private homes and industrial workshops.

IN fuel briquettes a minimum of hydrocarbons remains. They, in fact, are the most valuable females in coal.

From it you can obtain pure benzene, toluene, xylenes, and coumorane resins. The latter, for example, serve as the basis for paint and varnish products and such materials interior decoration rooms, like linoleum.

Some hydrocarbons are aromatic. People are familiar with the smell of mothballs. But few people know that it is produced from coal.

In surgery, naphthalene serves as an antiseptic. In the household, the substance fights moths.

In addition, naphthalene can protect against the bites of a number of insects. Among them: flies, gadflies, horseflies.

In total, coal in bags purchase for the production of more than 400 types of products.

Many of them are by-products obtained from coke production.

Interestingly, the cost of additional lines is generally higher than that of coke.

If we consider the average difference between coal and goods made from it, it is 20-25 times.

That is, production is very profitable and pays off quickly. Therefore, it is not surprising that scientists are looking for more and more new technologies for processing sedimentary rock. There must be supply for growing demand. Let's get to know him.

Coal mining

Coal deposits are called basins. There are over 3,500 of them in the world. The total area of ​​the basins is about 15% of the land area. The USA has the most coal.

23% of the world's reserves are concentrated there. Hard coal in Russia– this is 13% of total reserves. from China. 11% of the rock is hidden in its depths.

Most of them are anthracite. In Russia, the ratio of brown coal to black is approximately the same. In the USA, the brown type of rock predominates, which reduces the importance of deposits.

Despite the abundance of brown coal, the US deposits are striking not only in volume, but also in scale.

The reserves of the Appalachian coal basin alone amount to 1,600 billion tons.

Russia's largest basin, by comparison, stores only 640 billion tons of rock. We are talking about the Kuznetsk field.

It is located in the Kemerovo region. A couple more promising basins have been discovered in Yakutia and Tyva. In the first region, the deposits were called Elga, and in the second - Elegetian.

The deposits of Yakutia and Tyva are of the closed type. That is, the rock is not near the surface, but at depth.

It is necessary to build mines, adits, shafts. It's uplifting coal price. But the scale of the deposits costs money.

As for the Kuznetsk basin, they operate in a mixed system. About 70% of raw materials are extracted from the depths using hydraulic methods.

30% of coal is mined openly using bulldozers. They are sufficient if the rock lies near the surface and the covering layers are loose.

Coal is also mined openly in China. Most of China's deposits are located far outside the cities.

However, this did not prevent one of the deposits from causing inconvenience to the population of the country. This happened in 2010.

Beijing has sharply increased its requests for coal from Inner Mongolia. It is considered a province of the People's Republic of China.

So many trucks loaded with goods hit the road that Highway 110 was stopped for almost 10 days. The traffic jam began on August 14th, and only resolved on the 25th.

True, it could not have happened without road work. Coal trucks made the situation worse.

Highway 110 is a state road. So, not only was the coal delayed in transit, but other contracts were also under threat.

You can find videos where drivers driving along the highway in August 2010 report that it took about 5 days to cover the 100-kilometer stretch.