Definition Of Coal

Definition Of Coal

Coal is a combustible black or brownish-black sedimentary rock

More About Coal

• The harder forms, such as anthracite coal, can be regarded as metamorphic rock because of later exposure to elevated temperature and pressure
• Coal has been used as an energy resource, primarily burned for the production of electricity and/or heat, and is also used for industrial purposes, such as refining metals
• A fossil fuel, coal forms when dead plant matter is converted into peat, which in turn is converted into lignite, then sub-bituminous coal, after that bituminous coal, and lastly anthracite
• It is hard as stone and black in colour
• About 300 million years ago the earth had dense forests in low lying wetland areas. Due to natural processes, like flooding, these forests got buried under the soil
• They slowly got converted to coal under high temperature and pressure & due to compression and as more soil deposited over them they got compressed
• The slow process of conversion of dead vegetation into coal is called “Carbonization”
• Since it formed from the remains of dead vegetation it is called as fossil fuel
• When heated in air, coal produces carbon dioxide
• Coal is processed in industry to get coal tar, coal gas and coke
• Coke is the tough, porous and black carbon which is almost the pure form of carbon
• Coke is a solid carbonaceous residue derived from low-ash, low-sulfur bituminous coal from which the volatile constituents are driven off by baking in an oven without oxygen
• Coal tar is a black, thick liquid with unpleasant smell. It is a mixture of about 200 substances
• Coal gas is obtained during the processing of coal to get coke

Applications of coal: