Anthracite is a type of high quality fossil coal. It is characterized by a high level of metamorphism (the degree of solid-phase and structural mineral changes).
Like other types of minerals, anthracite - coal is formed over many millennia from plants that were without oxygen under the soil layers. Over a significant period of time, they were subject to coalification and humification processes. This served the formation of this substance. Carbon got its international name from the word carbon - coal. This is a reliable fact. Anthracite is the highest quality type of coal. It is also called carbuncle.
Characteristic Features of Anthracite
In this case, several parameters are distinguished. Namely, the presence of:
- saturated black or black and gray;
- strong shine;
- calorific value;
- significant electrical conductivity;
- high hardness and density.
Features of the formation of this fossil
Several processes are considered here. Anthracite is formed in a certain order. First peat is formed, and then brown coal . Further, under certain influences, this fossil passes into another substance. Namely in coal and anthracite. In the latter case, this is a transition link to graphite.
Anthracite (coal) lies at a depth of about 6 km. Places where these fossils often self-generate are characterized by peculiar shifts of the earth's crust. These are mainly spurs of mountains.
The most numerous deposits of anthracite are located in the coal basin in the Donetsk region.
Coal Anthracite: Product Feature
In this case, there are many certain nuances. Anthracite (from the Greek. Anthrakitis) is a humus fossil coal. He has the highest degree of metamorphism. When observing it under a microscope, it can be seen that plant residues are difficult to distinguish. Anthracite is a coal that has a black color, often with a grayish tint. Occasionally in its color and mottled escapism. He gives a black and velvety line on a porcelain plate. Anthracite (coal) is also characterized by a strong metallic luster. It has a high viscosity, does not sinter, has good electrical conductivity. Its highest hardness on the mineralogical scale is 2.0-2.5, and the organic mass density is 1500-1700 kg / m3. The heat of combustion is 33.9-34.8 MJ / kg (8100-8350 kcal / kg). It has an analytical low humidity of 1-3% and contains up to 9% of volatile type substances, 93.5–97.0% carbon, 1-3% hydrogen, oxygen and nitrogen 1.5–2.0% in a combustible mass. This is a definite fact. This fossil, which contains carbon in a combustible mass of more than 97%, is called superantracite. By volumetric yield of volatile substances, this product is divided into two industrial brands. Namely: with the presence of 220-330 l / kg, these are semi-anthracites, and with the presence of a volume output of less than 220 l / kg, anthracites.
Benefits of a Specified Fossil
This product is the highest quality type of coal mined. It differs significantly from other types, as it has the following parameters:
- High carbon content. In this case, it is 94-99%.
- Low sulfur content.
- High specific heat of combustion.
- Low moisture content.
- Burns without smoke and flame.
- It burns out quickly.
- High density organic mass. In this case, 1500-1700 kg per square meter.
- The specific gravity of anthracite coal is 1.5-1.7.
- High conductivity.
In addition, coal anthracite, the photo of which is provided in this text, does not sinter during combustion. Its hardness according to the level of mineralogical scale is 2.0-2.5. Another significant advantage is that up to 5% of volatile substances are released in the air during the combustion of anthracite.
In this type of fossil, the calorific value is superior to any other coal, namely: 8,200 kilocalories per kilogram. In comparison, the calorific value of gas is 7000 kcal / kg.
What types are the fossils classified into?
Coal fossil anthracite is a high carbon product. This was described above. This and a number of other characteristics play a role in determining its scope. According to the size classes, such a fossil as coal anthracite is classified (GOST 19242-73). Separation is carried out by the size of the fractions of this product. Namely:
- "AKO" - anthracite fist, nut. In this case, fractions having a size of 26-100 mm are taken into account.
- "AK" - anthracite large coal, fist. This includes fractions whose size is 50-100 mm.
- "AO" - coal brand anthracite walnut. The size of the fractions is 26-50 mm.
- "AM" is a small anthracite. In this case, fractions of 13-25 mm are taken into account.
- "AS" - coal brand anthracite seed. This includes fractions having a size of 6-13 mm.
- "Ashlam" is anthracite sludge. It is a kind of coal preparation product.
- "ASH" - a block of anthracite. In this case, the fractions are less than 6 mm.
The production of anthracite is carried out in the respective mines. They have a depth of up to 1,500 m. Then coal from the mines goes to enterprises for its processing. There it is enriched and sorted into fractions. After that, coal in bags (anthracite) is supplied to various consumers.
The implementation of this product is carried out both in the ordinary form (AR) and in concentrated enriched form. The specified fossil under the brands "AM" and "AKO" are identical in properties. Although the resistivity of fine coal is higher.
Use of anthracite
This product is quite popular. Anthracite is the most dense type of coal. This allows him to occupy the first positions in the class of heat transfer and combustion time. If you buy anthracite (coal) for heating, then you will need it much less for heating the same area than if you use a similar product of a different kind or firewood. Despite all the advantages of this fossil, it also has disadvantages. Having a significant density, it is not able to flare up in all types of boilers and furnaces. This is important to know. For good burning of anthracite, you need a good supply of air. Basically, in modern types of solid fuel boilers, it is forced. Coal species of lower density include: low-caking and long-flame coal.
Anthracite, due to its calorific value, is superior to other analogues. This parameter is 8200 kcal / kg. For example, natural gas - 7000 kcal / kg. Anthracite is coal, which is the hardest of all its analogues. When burning volatile substances, only 5% of it is released. Anthracite is used in various fields of human activity. Namely: in industrial type production (chemistry, metallurgy, sugar industry, etc.), in the communal area (water heating, heating, and so on). It is also used to heat private households. Filtrants are also produced from this fossil, which are used to treat wastewater, water and so on.
Anthracite in the electric power industry
In this area, the use of the specified product is also significant. Screenings from anthracites, which have a high ash content of class 0-13, are widely used as fuel in the electric power industry. In this industry, this fossil is used because of its low volatile content. In the electric power industry, special equipment is used to burn anthracite.
For the pulverized combustion of this product, fire chambers of a special design are also required. Their configuration is quite peculiar. It should ensure the complete burning of the specified fossil at a time when it is in a special combustion zone.
Coal with small fractions, as well as low in sulfur, nitrogen and phosphorus is used in special boilers that are designed for this. The specified small product is also used in cement kilns.
Anthracite in metallurgy
In this area, this fossil has also found its application. Anthracites in metallurgy are used for sintering iron and limestone. The blast furnace and electric steel smelting processes do not properly control the number of harmful substances emitted into the atmosphere. Therefore, the use of the specified high-quality fuel by default allows us to make metallurgical processes more environmentally friendly.
In addition, this small-scale fossil is used in the production of high-carbon steel for secondary carburization. In blast furnaces with PCI systems (pulverized fuel injection), anthracite can also be used. Here the main indicator is the moisture content of the coal that is supplied.
In this case, said fuel may be blown into the blast furnace with a bayonet. This technology is very well used by countries in Western Europe, as well as in Asia - by China, Japan, and Korea. In Russia and Ukraine, this method is only gaining popularity.
In the metallurgical industry, coal is also used as a metal reducer.
Anthracites - sorbents
This is one of the most promising areas in the use of this fossil. Anthracite can be used to purify drinking and waste water. In this case, it acts as a filter and can easily replace activated charcoal. This is a significant factor.
Alternative high carbon raw materials
The coal market is traditionally divided into two segments. They mean energy and coke production. Price trends for products depend on the segment and other factors. And often they are different.
Anthracite is a unique product successfully present in two segments. In addition, it still occupies a significant place in the specialized market for technological use. The price dynamics for similar products in different segments may differ, that is, redistribution occurs in this regard. For example, if the cost of one segment for anthracite falls, then the other, as a rule, grows.
Anthracites safely compete with graphite, charcoal, petroleum coke. The amplitude of their prices will therefore depend on the cost of electrical energy, metal products and so on. This is important to remember. In addition, the state of the global economy will affect the price of anthracite. However, over the past decade, a constant dynamics of its growth has been noticeable.
Conclusion
Based on the above, it can be said that coal, anthracite stone, is the most common type of mineral in the world. It has a high level of net output of high-quality energy in the generation of electricity and heat with high temperature for production processes. It is used in the chemical industry and is relatively inexpensive. With modern science and technology, it is impossible to completely replace anthracite in industry. This is a reliable fact. Consequently, in the near future there will be an intensive continuation of the production of anthracite and coal.