Coal, whose origins date back to geological times, still accounts for around 35% of the world’s energy production. There are several types. One of the most distinctive is anthracite coal, a particularly sought-after fuel!
The formation of anthracite coal
The term coal refers to a group of solid, black-colored fossil fuels. It is the result of the accumulation and transformation of biomass (plant matter) buried several kilometers deep underground for hundreds of millions of years. Like natural gas and oil, coal is also a fossil fuel whose formation began over 400 million years ago.
Under the effect of the rising temperatures and pressures of the earth’s crust at a depth of several kilometers, the buried plants decomposed and underwent a transformation process that resulted in a dark, solid, combustible material with a high carbon content: coal.
Anthracite coal, still the oldest and most sought-after coal, dates back to the Carboniferous era (nearly 300 million years ago). So we understand that there are several varieties of coal, each type corresponding to a specific stage of maturity (percentage of carbon and volatile matter). Anthracite is over 90% carbon and less than 10% volatile matter. This makes it an excellent fuel that is still used to heat homes.
Anthracite coal mining
Anthracite coal mining begins with prospecting and geological mapping techniques to determine the existence, nature and extent of deposits. A good understanding of the geology of these deposits is essential for mining.
When deposits extend into underground mines several kilometers below the surface, extraction shafts, galleries and vents are dug down to the site of the deposit. On the surface, an industrial site is set up to sort coal.
There are also open-pit mines where the deposits are only a few dozen meters underground. In this case, mining is carried out in successive layers. The mines are structured in the form of quarries, and as they are extracted, the spoil is used to fill in the craters created. The anthracite coal extracted is then washed and distributed according to industrial and domestic needs.
Often considered an archaic energy source, coal nevertheless plays a major role in the world’s energy mix. Anthracite coal is still used on a large scale in Asian and Central European countries where oil and gas resources are limited. And it’s likely to stay that way for decades to come, with large deposits in China, North America, Russia, India, South Africa and Australia. This diversity of sources will ensure a secure global supply for many years to come.
The benefits of anthracite coal
Anthracite coal is a hard coal with a very high calorific value. As a result, it is usually used in industry and for domestic heating purposes. It burns slowly and evenly, with few flames. It produces no soot or tar, making it easy to maintain appliances such as boilers, stoves, inserts, fireplaces and convectors. This makes it very economical, and its market price is relatively low.
Many innovative farming and processing techniques have now been developed, with the aim of making farms “cleaner”. The future of global production depends on it, as does the perfecting of coal-to-energy conversion processes. Managing the carbon and climate impact of using anthracite coal has therefore become a central issue.
The energy optimization of coal-fired power plants and the increased integration of CO2 capture and geological storage technologies are playing a key role in the development of a new era of “clean coal”. With the adoption of capture and geological storage methods, carbon dioxide released into the atmosphere is recovered and trapped in deep layers of the earth. However, in their practical phase, these salutary projects are confronted with enormous economic and technological constraints that hamper their widespread application.
Anthracite coal selection criteria
Anthracite charcoal is commercially available in bulk and in bags of various capacities to prevent dirt and dust, among other things. A few selection criteria will help you get the most out of coal’s calorific value:
Humidity level
Moisture content is the first criterion for choosing anthracite, in addition of course to its low volatile matter content, a sign of good energy performance. The lower the moisture content, the higher the calorific value of the coal. And anthracite coal essentially contains less than 5% moisture and over 90% carbon.
Energy power
The energy content or lower calorific value indicated by the manufacturer gives information on the number of calories available for heating purposes following vaporization of the moisture contained in the fuel. The higher the calorific value, the better the energy supplied by anthracite coal.
Size
Coal size is the other essential selection criterion. When anthracite coal is small, it settles quickly and impedes air circulation. Oxygen is what sustains a flame, hence the need to choose a larger or smaller gauge.
Ash percentage
By checking the ash percentage, you can choose the durability of your anthracite coal. It also means less pollution. It should therefore be as low as possible. In fact, ashes prevent air infiltration and require constant evacuation.
Good to know: anthracite is a natural and less expensive fuel. According to statistics, nearly 25% of the world’s discovered reserves are located in the United States. China alone consumes almost half the world’s production. In Europe, anthracite coal is mainly used for industrial and domestic purposes. You’ll find them for your personal needs in specialist outlets, DIY stores, some supermarkets and on the Internet.
