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:

  • Coke is used in the manufacture of steel and in the extraction of many metals
  • Coal tar is used in the manufacture of many substances such as dyes, drugs, explosives, perfumes, plastics, paints, photographic materials, roofing materials and naphthalene balls
  • Coal gas is used a s a source of heat and as a fuel in many industries
  • Coal is one of the fossil fuels used to cook food
  • Earlier it was used in railway engines to produce steam to run the engine
  • It is also used in thermal power plants to produce electricity
  • Coal is used as fuel in various industries