Ordinary coal. How to choose coal for heating, its characteristics and types. Benefits of using coal in heating systems

There are three types of coal for heating: brown stone and anthracite. Its marking is carried out using letter designations.

The first letter indicates the brand of coal:

  • Brown coal is designated by the letter "B";
  • Hard coal is divided into:
    • D - long-flame;
    • G - gas;
    • F - fatty;
    • K - coke;
    • T - skinny;
  • Anthracite is designated by the letter "A"

The second is its size class (see table):

What kind of coal is used to heat the house?

When deciding which coal is better for heating, anthracite is first of all remembered. This type of coal has the best fuel characteristics in terms of such parameters as minimum consumption, maximum heat transfer, uniform and long burning of each loaded batch, and the minimum amount of slag formed during combustion.

This brand of coal contains less than 1% sulfur and only about 10% ash, which allows us to talk about minimal harm. environment(min emissions of sulfur dioxide) and a significant increase in the life of chimneys and boilers. Sulfur and water vapor, when interacting, form sulfuric and sulphurous acids, which negatively affect the design of chimneys and heating boilers.

The amount of coal you need for the heating season directly depends on its quality.

Anyone who chooses coal for heating, despite all the advantages of anthracite listed above, cannot definitely recommend it, since anthracite has two drawbacks that play important role for owners of private houses. First, anthracite is the most expensive grade of coal. Secondly, it is extremely difficult to kindle it.

Therefore, most often, for heating a house with coal, preference is given to long-flame coals (WPC), which are well suited for almost any solid fuel heating boilers, as well as for classic fireplaces and stoves. As additional advantages of coals of this grade, it should be noted that they:

  • Easy to ignite, easy to use;
  • Demonstrate the best quality/price ratio;
  • Burning with flames long tongues, similar to burning firewood;
  • The process of burning one bookmark takes a lot of time and is accompanied by the release of large volumes of heat;
  • For sustainable combustion, an additional blower is not required.

That is why long-flame coal is purchased not only by owners of private houses, but also by boiler houses of schools, administrations different levels, hospitals, etc.

The specified coal in stationary boiler plants has proven itself both in pulverized and in layer combustion. Therefore, almost all commercially available fractions of coal of the specified grade are in demand by the consumer: from "P" to "M".

Benefits of using coal in heating systems

Heating with coal in a private house has a number of significant advantages.

  • Coal is mined in Russia and is not subject to such price fluctuations as liquid fuels.
  • Its use does not require the presence of special gas pipelines, as for gas-fired heating.
  • The cost of coal is lower than gaseous or liquid fuels.
  • This type of fuel is easy to transport and convenient to store.
  • Heating a house with coal is beneficial, as it is able to retain heat during combustion. Therefore, the air heated in the room does not cool for a long time.
  • The high heat transfer of the specified fuel allows using its minimum volumes to maintain a comfortable temperature even in the most severe frosts.
  • Coal is a problem-free fuel. In order for the heating to function properly, it is enough to initially install a chimney of the correct design and clean it in a timely manner.
  • Storing the specified fuel is easier than the same firewood, for example. It is supplied to the consumer in bags. The only requirement for a place to store coal is that it must be dry.

The exact consumption of coal will always help you to do it at the place of its sale. And to roughly determine how much fuel you need for the heating season, the recommendations below will help. Despite the fact that this method is one of the simplest, it, at the same time, allows one to obtain fairly accurate results.

For a unit of measurement, we take a bucket with a capacity of 10 liters, which is a must-have in any private house (although officially the volume of coal is usually measured in tons). We take the average weight of coal in one full bucket equal to 18 kg (you can check).

Practice shows that, when using a typical solid fuel boiler, for heating a house with an area of ​​​​about 200 sq.m. Depending on the season, there are the following coal consumption rates for heating:

  • September-October - one bucket per day (i.e. 18 kg according to our assumption);
  • November - February - ten buckets per day, which is equal to 180 kg;
  • March-April - from one to two buckets per day. On average 22 - 24 kg.

Having calculated the total amount of coal required, we get that during the heating season, the consumption of coal for heating the house will be about 580 buckets. Multiplying this amount by 18, we get that for the season we need about 10440 kg.

If you consider such a calculation option to be archaic, and are inclined to solve everything from a scientific point of view, then we offer you the following option for preliminary determination of the required volumes of coal.

In order to receive 1 kW of energy, it is necessary to burn about 200 g of coal in a boiler.
For the whole season, while heating is required, it will be necessary to receive about 50,000 kW.

This implies. What you need for the season 0.2 x 50,000 = 10,000 kg. That is, the same 10 tons that we reached in the previous version.

Having resorted to this simple arithmetic, do not forget that each grade of coal has own indicator energy efficiency. Therefore, having made a decision to purchase and choosing a seller, consult on the spot about what coal consumption for heating your house will be when buying coal of this brand.

The article is devoted to the grades of coal and their difference. To distinguish types of coal, there is a division into grades:

  • A - anthracite
  • B - brown
  • G - gas
  • OS - lean sintering
  • SS - slightly caking
  • T - skinny.
  • D- long-flame
  • F - fat
  • K - coke

In total, there are 17 grades of coal: "D", "DG", "Zh", "KZh", "G", "GZhO", "GZh", "K", "KO", "KSN", "KS "", "OS", "TS", "SS", "T" "AM", "AO", "AS", "AK", "AKO", "ASH" "B1", "B2", "B3 ". By enrichment, coals are divided into middlings, the branch of metallurgy. For concentrates - this is our energy, for power plants and sludge - for the population and for coal briquetting. Oxidation is designated OK, OK2, OK1.

Coal fraction designation anthracite:

  • P - plate (≥100mm)
  • AK - large (50 - 100mm)
  • AKO- fist walnut (25-100) ()
  • JSC- walnut (25-50mm) ()
  • AM- small (13-25mm) ()
  • AC- seed (6-13mm) ()
  • AS- shtyb (0-6mm) ()
  • R - private (0-200)
  • career 0–300 mm

There are also mixed brands. If we give an example of the designation of brands, then GKOM (K - 50-100, O -25-50, M - 13-25) is 13-100 mm. When coal is formed, this process is also called metamorphism, then the formed coals are divided into stone, brown and anthracites. Anthracites have the highest calorific value. For the energy industry of Ukarina, coals look the most pleasant, because they have the most favorable ratio based on the amount of money spent to the calorific value. For example, coals of grade D and grade G can be cited, they transfer excellent amounts of heat and can burn without blowing, they are often used for combustion in boiler rooms. But coals SS, T and OS are used as a rule in the energy sector. The justification for using these types of coals is appropriate if they are used in large quantities, since the implementation of the combustion process requires more economic costs. For the production of steel and cast iron, G and Zh grades are used.
Grade "A" (anthracite). Large fractions of anthracite are used mainly in the municipal sector of Ukraine. Very popular and widely used among the population of Ukraine. Also, this grade A coal has been widely used in the energy sector due to the high heat of combustion.

Mark "B" ( brown coal). What is typical in this brand is the yield of volatile substances over 45%. They are divided by humidity into: 1 B (above 43%), 2 B (29-45%), 3 B (up to 32%).

Designation of coking coal grades.

Mark "D" (long-flame coal). Possesses poor sintering properties. As well as grade A coal, it can be used both in the energy industry of Ukraine, and in the domestic sphere and in the chemical industry of Ukraine, for molded coke, in the coking process.

Brand "DG" (long-flame gas coal). On the contrary, it has high sintering properties and slight brittleness. But, the resulting coke is unsuitable for further use, since it has a high reactivity and low strength. This brand has coals of medium and large classes in terms of fractional composition.
Grade "G" (gas coals). It is involved in the domestic sector of our state, as a cheaper replacement for grade A coal. Due to its properties, it can be used in the process of gasification, coke formation, semi-coking process. They are divided into the following technological groups: inertinite, vitrinite. Low-ash vitrinite is used to produce synthetic fuels.

The most valuable type of coking coal. Structural strength is one of the distinguishing features of coke obtained from Zh.

Brand "GZhO" (gas fat lean coal). They make up more than half of the charge and are an excellent product for coking. They can also be used for household needs of the population of Ukraine, if they are fusinite. Unsuitable for the production of coke for metallurgy.

The main purpose is to obtain metallurgical coke, conditioned. However, they are not mixed with other types of coal.

Brand "KZh" (coke fat coal). It is widely known that this brand of coal is used in the coke industry in Ukraine. The highest coking index, which makes it possible to obtain methcoke from this type of coal. They have the following features:

  • – vitrinite reflections from 1.5 to 1.9%,
  • - the yield of volatile substances is not more than 19.6%,
  • – humidity 6-13%,
  • – ash content from 6 to 39%,
  • – carbon 78-92%,
  • - hydrogen 4.2-5%.

SS - weakly caking. Found application in power plants, boiler houses and in the municipal sector of Ukraine. This type of coal is characterized the following indicators:

  • – vitrinite reflections 0.5-1.78%,
  • – humidity 8-9%,
  • – ash content from 8 to 45%,
  • — sulfur not more than 0.8%,
  • – carbon from 74 to 90%,
  • — hydrogen from 4.0 to 5.0%.

T - skinny. One of the main indicators is complete absence caking. Found application in the energy industry of Ukraine, as well as for domestic needs.


BUT– anthracite

B– brown

G– gas

D- long-flame

AND- bold

To– coke

OS- lean sintering

SS– slightly caking

T– skinny

At the end of the name of the brand of coal there may be an abbreviation OK(OK1, OK2), indicating the degree of oxidation.

Also, depending on the degree of enrichment, coals are divided into concentrates, intermediate products and sludge. Concentrates are usually used in boiler houses and for generating electricity. Industrial products are usually used for the needs of metallurgy. Briquettes can be made from the sludge and retailed to the public for personal use.

Depending on the degree of coalification (metamorphism), there are brown coals, hard coals and anthracites. The most low heat combustion in brown coals, and the highest - in anthracites.

The most favorable ratio of price and specific heat of combustion is coal. Coal grades D, G and anthracites are used, as a rule, in boiler houses, because. they can burn without blowing. Coal grades SS, OS, T are used to obtain electrical energy, because they have a high calorific value, but the combustion of this type of coal is associated with technological difficulties that are justified only if a large amount of coal is needed.

In ferrous metallurgy, grades G and Zh are usually used for the production of steel and cast iron.

By marking coals, you can immediately determine their fraction.

Designation:

P– (plate) more than 100 mm

To– (large) 50-100 mm

O– (walnut) 25-50 mm

M– (small) 13-25 mm

FROM– (seed) 6-13 mm

W– (piece) 0-6 mm

R– (ordinary) mine 0-200 mm, career 0-300 mm

The fraction of a given coal grade is determined based on the smaller value of the smallest fraction and the larger value of the largest fraction indicated in the name of the coal grade. So, for example, the fraction of the DKOM brand (K - 50-100, O - 25-50, M - 13-25) is 13-100 mm.

Some solid fuel boilers can run on any fuel, but not all. Therefore, before buying coal, look into the passport of your unit. The brands under which the boiler was calculated should be indicated there. If there is no such information, you can go by the trial method. Most companies selling this type of fuel have coal in bags. You will need to take a bag of different grades and fractions, and alternately drown each of them. Try to use the same amount of coal and evaluate such parameters as the amount of heat, burning time and the amount of ash.

Qualitative indicators of coal

Hard coal contains a large number of very different components, each of which can affect the area of ​​\u200b\u200buse, which makes coal quality control a task that is not at all easy. Depending on the application, a number of defining characteristics are considered. For example, when determining the suitability of coal for coking, more than 30 parameters are taken into account.

To determine suitable coal for solid fuel boiler or not, it is not necessary to know all its properties. It's important to know:

If we talk about this fuel in general, then anthracite is considered the best coal for a domestic heating stake (indicated by the letter “A”): it burns for a long time, white smoke emitted during combustion (little soot is formed), has a low ash content. But not everyone loves it: firstly, it has a high price, and secondly, it is very difficult to ignite.

Long-flame coal has the most optimal characteristics in relation to the price for household boilers. It burns for a long time, while the flame is long, as when burning wood (hence the name), has a fairly high calorific value and flares up easily. Long-flame coal is marked with the letter "D". They also use weakly sintering "SS" and lean "T" for heating private houses, but their quality indicators are much worse.

When marking fuel, in addition to the type of fuel, the size of the fraction (the size of the pieces) is also indicated:

So if long-flame coal is marked as WPC - this is slab coal, crushed into pieces from 50 to 100 mm, DS - long-flame "seed", etc. It is worth explaining what "ordinary coal" is. It has an unregulated composition, i.e. it can contain, for example, 80% of large and medium fractions and only 20% fines, or maybe vice versa.

It is impossible to say unequivocally which coal is better. Much depends on the boiler: some are designed for brown coal, and some for anthracite. And if the passport indicates that it is recommended to use anthracite, then it is not necessary to look for a cheaper replacement for it: a ton of coal will cost less, but much more will be needed. So it will not be possible to save money, but to spoil the boiler is easy.

For those who do not have a passport for the boiler or use a brick oven for heating, you can use the advice of experienced people. It is better to melt a household boiler with long-flame coal of the "nut" fraction. After it flares up well, for heating during the day, anthracite is poured in an even layer. It burns for a long time, giving out a large amount of heat. In the evening, in a well-heated anthracite cauldron, you can pour a “seed” that will “keep” the temperature until the morning. But again, we repeat, everyone has different boilers, so you need to choose the optimal mode yourself. The point here is not only in saving money, but in the optimal temperature regime, under which both people are comfortable and the equipment works in its normal mode.

The owners of brick ovens are advised to kindle it with firewood. Then, when the furnace warms up, coal briquettes (a good type of fuel) are placed in it or a “seed” is poured, preferably a long-flame one. At the same time, until the coal has flared up, the blower and dampers must be kept open for maximum oxygen supply. When this bookmark flares up well, and the stove picks up heat, you can fill in a larger fraction, for example, “large” or “nut”.

Others advise to lay a "nut" in a brick oven after firewood, and a "seed" at night. With this order, the seed smolders in a heated oven, maintaining the temperature until the morning.

How to calculate the amount of coal for the winter

The amount of coal needed to heat a house depends on many parameters:

  • from the heated area and from the material from which the house is built;
  • on how it is insulated and what windows are, how tightly the doors are fitted;
  • on the type of heating and type of boiler, type of coal;
  • on the severity of winters in your area and their average duration, etc.

All these "little things" are very important. So most of the coal will be needed for heating a brick house - 30-35% more than for a wooden similar area or a house made of aerated concrete blocks. For heating a well-insulated cinder-block house (wall thickness 45 cm) with an area of ​​90 m 2, the owners spend 2.5-3.5 tons of coal (1 ton of anthracite "walnut" and two "seeds"). Heating stove. For others, a house of the same area, but without insulation, takes about 6-7 tons.

Owners of 2-3 room apartments in the same region buy 1.5-2 tons to feed solid fuel boilers. In another region, for heating a wooden house 80 m 2 from a bar, 5 tons of coal and firewood are bought, but their winters are harsh - up to -40 ° C for a month and a half and the rest of the time -20 ° C.

To determine how long a ton of coal will last for you, it is recommended to buy several bags of the selected brand (and in the place where you plan to buy) and see how much it is required per day to maintain a comfortable temperature. Take into account the "outboard" temperature and compare it with the average during the winter. Draw conclusions from the results. If you are drowning for the first year, try to take it with some margin. If it remains, it doesn’t matter, it does not lose its properties (unless you bought brown coal), but if it’s not enough, it’s already unpleasant.

How to store coal

Coal of different grades and even different deposits behaves differently during storage. Some can be stored for years with virtually no loss of quality, and some after six months turns into dust and dust. It all depends on the composition and quality of the fuel, as well as on storage conditions.

Depending on the resistance to oxidation (due to which the change in characteristics and "weathering" occurs), coal is divided into four categories:

  • Most Resilient. This group includes anthracites and semi-anthracites, which in large pieces (the size of a soccer ball and up to the size of the "P" fraction) can be stored without a noticeable loss of quality up to 36 months, smaller fractions from "K" and less - up to 24 months. This category includes coals from pools:
    • Suchanskoye - TR, GR - stored for 36 months;
    • Cheremkhovskoye - DR, DKO - 36 months;
    • Pechorsky - ZhR, ZhSSh, ZhSh - 24 months;
    • Donetsk - TR, KR - 24 months;
    • Podgorodnenskoye - TR - 24 months.
  • Resistant to oxidation. Stored 18 months
    • Donetsk basin - GK, GKO, GO, GM;
    • Kuznetsk field - TR, TK, TO, SS K, SSKO, SSM;
    • Irtysh (Ekibastuz) - SSR;
    • Karaganda - KR, KZhR;
    • Sakhalin ZhR, KR GR, GKO;
    • Uralskoye GR
    • Shartun SSS
    • Kuu-Chekinskoye K2R
    • Bukakachinskoye GR
  • Medium stability. Stored for 12 months.
    • Kuznetsky - DKO, DM, KR, KZhR, ZhR, K2R, GK, GKO, GO, GM, GKOM;
    • Kizelovsky - GR, GMSCH, GSSh, JE;
    • Donetsk - DKO, DM, DK, DO, GR, GMSCH, GSCH, GShch, R, F;
    • Pechorsky - DKO;
    • Sakhalin - DR, DSSh;
    • Lvovsko-Vsyaynskoye - GR, GK, GMSSH, GSSh;
    • Egorshinsky - GR;
    • Shargunskoye - coal briquette;
    • Tuva, Neryunfinskoye - KR;
    • Zyryanskoye, Chulmanskoye - ZhR.
  • Unstable. Stored for 6 months.
    • Kuznetsky - GR, GSSh, GMSSH;
    • Pechorsky, Donetsk, Lipovets - DR, DSSh;
    • Khakassian - DR, DMSSH;
    • Central Asian - DK, DOM, DKOM, DR, DSSh;
    • Tkvarchelskoye - ZhR;
    • Tkibulskoye - DK, DKO, DOMSSH, DR, GR, coal briquette;
    • Arkagalinskoye, Beringovskoye, Dzhebari ki-Khaya, Kotuyskoye, Sangarskoye, Tal-Yuryakhskoye, - DR.
  • Brown coals. Stored for 6 months.
    • Artemovskoye, Tavrichanskoye - BK, BKOM, BR, BOM, BSSH;
    • Raychikhinsky - BK, BO, BMSSH, BR;
    • Podmoskovny — BR, BK, BO, BOM, BOMSSH, BMSSH, BSSH;
    • Right-bank Ukraine - BR, brown coal briquette;
    • Chelyabinsk - BK, BKO, BMSSH, BO, BSSH, BR;
    • Babaevskoe - BR, brown coal briquette;
    • Smolyaninovskoye, Maykhinskoye - BKOM, BSSH, BR;
    • Retgikhovskoye - BP, BSSH, BKOM, BR;
    • Azeyskoe, Anadyrskoe, Akhaltsikhe, Arbagaoskoe, Bogoslovskoe, Volchanskoe, Veselovskoe, Gusinoozerskoe, Transcarpathian, Irsha-Borodino, Kolomiyskoe, Kangalakskoe, Tarbagataiskoe, Soginskoe (Tiksi Bay), Chernov, Kharanorskoe, Khasanskoe - BR;
  • Brown coals. Stored for 4 months.
    • Central Asian - BSSH, BR;
    • Angren - BOMSSH, BR;
    • Lengerovskoe, Nazarovskoye - BR.

These are the storage periods for enterprises selling coal from open areas. Approximately the same amount of coal will be stored in a private courtyard without losing its characteristics. Then the process of oxidation and weathering begins. You can extend the shelf life of coal by storing it under a roof. The coal shed or basement should have a low temperature and preferably no direct sunlight. Oxidation of coal begins at 20-25 o C. At a temperature not exceeding 40 o C, the process occurs slowly and is expressed in a decrease in the strength of the pieces, the appearance and deepening of cracks. This process is also called weathering. Since oxidation occurs with the release of heat, the temperature inside a large pile of coal gradually rises, which can lead to spontaneous combustion. This problem is most likely when using low quality fuel with a high content of fines and/or dust. Brown coals have the highest probability of spontaneous combustion, followed by bituminous coals with a porous structure (lignite and subbitominous). Anthracites are the least susceptible to both oxidation and spontaneous combustion.

Proper storage of coal is not an easy task

If you store coal of small fractions such as "seed" or "chunk", you need to periodically check its condition. If the stocks are large, it makes sense to purchase an electronic thermometer, to which to attach a long thermocouple (temperature sensor) and periodically, at least once a week, monitor the condition. Auto-ignition temperature of coal:

  • Brown - 40-60 o C;
  • Fatty coals - 60-70 o C;
  • Skinny and anthracite - 70 o C.

Wetting coal to bring down the temperature is not recommended - wet coal absorbs oxygen much better than dry coal, and when it dries, gas exchange improves even more, which makes the oxidation process even more active. The most reliable way to prevent spontaneous combustion is to limit the access of oxygen - cover with a tarpaulin, thick plastic wrap, etc.

As an alternative to coal can be considered. These are small fractions of coal, which are compressed into briquettes. They have a high calorific value and ash content, less than that of the original product, they burn for a long time and practically without smoke. Another type of fuel for which you do not need to remake a conventional solid fuel boiler is fuel. They give a little less heat per kilogram, but they are much cheaper and there is very little ash left after combustion.

Hard coal is one of the most sought-after minerals, the extraction of which requires enormous efforts and takes place in very unsafe conditions. Its deposits are located deep underground, formed as a result of a violation of the decay of plants caused by a lack of oxygen. In everyday life and industry, various grades of coal are used, corresponding to the accepted classification based on quality characteristics.

Coal grades vary. at least in terms of quality.

Description and purpose of the mineral

In wetlands, plants are converted into peat under the action of many bacteria, then into brown coal, and it, in turn, turns into stone after many years. The latter is more high rate calorific value and therefore used as a fuel. The areas of its consumption are:

  • electric power industry;
  • thermal power equipment of industrial enterprises;
  • chemical enterprises;
  • Department of Housing and Utilities;
  • heating systems of private houses.

Depending on the marking of coal, it can be used as a solid fuel for modern heating boilers and conventional stoves in old houses. Despite their external similarity and even belonging to the same type, fossils can differ, for example, in sulfur content, calorific value, humidity, etc.

In this video, you will learn about the specifics of the SSR grade coal:

The cost of each brand of coal is also determined separately. Their characteristics affect how much a ton of fuel for an industrial or private facility will be valued. Study of properties and features produced in several directions:

  • elemental analysis (detection and calculation of oxygen, hydrogen, organic sulfur, carbon and nitrogen in the total mass);
  • technical studies - analysis of quality indicators that must comply with the requirements established by the standards (humidity and sulfur content, ash content and heat of combustion, the yield of volatile components);
  • mechanical analysis - the ability of a fossil not to crack or collapse, not to change size under the influence of friction or impact (important for foundry and electrode production);
  • thermal tests - allow you to determine the strength of coal under the influence of high temperatures (grades intended for furnaces, semi-coking);
  • determination of electrical properties - depending on the stage of transformation, coals can be dielectrics and semiconductors in the initial stages, and in the later stages - conductors.

Special laboratories examine absolutely all grades of coal. Their characteristics make it possible to sort pieces by size (fineness), as well as by other properties that affect quality.

Classification and properties

In the Russian classification, it is customary to distinguish 8 groups. This division does not coincide with the marking adopted in Western countries. Hard coal is presented in several grades with the corresponding letter designation:

  • brown (B) - with a calorific value of 7000-7500 kcal / kg;
  • skinny (T) - from 7300 to 8700;
  • long-flame (D) -7500-8000;
  • gas (G) - during combustion, it releases heat from 7900 to 8600 kcal / kg;
  • anthracite (A) - 8100-8750;
  • bold (F) - 8300-8700;
  • coke (K) - 8400-8700;
  • lean-sintering (OS) - 8400-8780.

The most common in the private sector and industry are long-flame coal (marking WPC or DPKO, popularly referred to as "fist" or "nut"), lean (marked TPK and TPKO, sizes 50-200 mm and 25-50 mm) and Anthracite coal (used most often in the energy sector).

Group characteristics

Stone mineral grade D is considered the most suitable type of fuel that ensures the operation of furnaces and heating boilers. This is a long-flame coal, which got its name because of the formation of high flames, like firewood. It supports a long burning process and releases a large amount of heat without sintering. This type of fuel can be used in almost any system (even those not equipped with natural draft or forced draft). It flares up very quickly, allows you to effectively heat private houses and medical institutions, administrative buildings.

Grade T coal can be considered the second most popular. It is called “lean”, it is characterized by the release of volatile substances in the range of 9-17%, it does not sinter, and practically does not emit flame during combustion. It contains about 90% carbon, so this coal is considered the richest. It is indispensable in the fuel industry, chemical production, gas generators, housing and communal services and mobile power plants.


So, brand D is the most popular

The third group is represented by long-flame gas DG coal, weakly caking, with slight brittleness and high strength. Unsuitable for coke blends because the resulting coke is radioactive. The yield of volatile substances is in the range of 27-30%, refers to energy rocks.

Under the brand Zh are two groups of fossils, the division of which is based on the volatilization index and the reflection of vitrinite. It's heavily coked, especially valuable view fuel, which, as a result of combustion, forms high-strength structural coke. For the production of iron or steel in ferrous metallurgy, Zh grade coal is most preferable, the characteristics of which make it possible to avoid technological difficulties associated with the combustion process.

Anthracite combines a group of coals with about 8% VLV, which are indispensable in the energy industry. Large and medium-sized specimens are used as smokeless fuel in the municipal and domestic sectors. In addition, anthracite is needed for the production of carbide (aluminum and silicon).

Intermediate marking

Labeling, adopted on the basis of qualitative indicators, allows you to select several groups and select the right mineral depending on your needs. Depending on the production basins, an intermediate classification is adopted, which highlights:

  • gas fat (GZH);
  • weakly caking (SS);
  • coke fatty (QOL);
  • coke second (K2).

When mining coal, it is possible to obtain pieces of different sizes, on the basis of which it is customary to divide them into classes. The class P (slab) includes specimens over 100 mm, large (K) - pieces from 50 to 100 mm. Class O (walnut) is represented by stones of 26-50 mm, and class M (small) is represented by rocks of 13-25 mm. Group C (seed) includes small coals of 7-13 mm, and shtyb (Sh) refers to all residues less than 66 mm in size. The designation P (ordinary) is assigned to fossils that are not limited in size.

 

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