Which are the Different Types of Coal?
There are different varieties of coal depending on the carbon content in them. The coal which has the highest carbon content is said to be the best among all coal types.
Anthracite is the best coal with the highest carbon content. It is the oldest coal and is subjected to high pressure and temperature as compared to the other types of coal, such as Bituminous coal and Lignite.
Which Products are Obtained from Coal?
The three main derivatives of coal are Coke, Coal tar and Coal gas. When coal is processed in a huge, oxygen-free furnace, these products are obtained. Let us look at them one by one.
Coke
Coal has many impurities. Selective removal of these impurities with the help of high temperature and pressure gives us coke. Coke is a pure form of carbon. It is tough, porous and is a black substance like coal.
Coke is a clean fuel; that is it burns with little or no smoke at all. Whereas the burning of coal produces a lot of smoke. That is why coke is preferred over coal as fuel.
Coke is generally used in the manufacturing of steel and extraction of metals.
Coal tar
One of the impurities in coke is coal tar. When coke is produced it is released as a by- product. Unlike coal and coke, coal tar isn’t a solid substance. It is a black and thick liquid and has an unpleasant smell.
Coal tar contains benzene, anthracene and phenol which are the raw materials that help produce dyes, drugs and some explosives as well. It is also used to make perfumes.
Coal gas
When coal is processed to get coke, coal gas is released as a by-product.
Until the 18th century, it was used as fuel to light streets up in both London and New York. Nowadays it is used for heating purposes rather than lighting.
Summary
| Types of Coal | |
| Anthracite, Bituminous coal, Lignite | |
| Derivatives of Coal | |
| Coke |
|
| Coal Tar |
|
| Coal Gas |
|
Did you know?
The largest coal mine in the world by reserves is the North Antelope Rochelle coal mine in the Powder River Basin of Wyoming, USA.