Classification of Coal in India
Depending upon its grade from highest to lowest following, The coal found in India can be classified as Anthracite Coal, Bituminous Coal, Lignite (Brown Coal), Peat etc. They are discussed below :
This is the best quality of coal and contains over 85 per cent carbon. It is very hard, compact, jet black coal having semi-metallic luster.
Anthracite coal ignites slowly and burns with a nice short blue flame. In India, it is found only in Jammu and Kashmir and that too in small quantity.
This is the most widely used coal and contains 50 to 85 per cent carbon. It is dense, compact, and brittle and is usually of black colour.
A good bituminous coal is composed of alternate dull and bright bands. Its calorific value is very high due to high proportion of carbon and low moisture content. Most of the bituminous coal is found in Jharkhand, Orissa, West Bengal, Chattisgarh and Madhya Pradesh.
Lignite ( Brown Coal)
Also known as brown coal, lignite is a lower grade coal and contains about 35-50 per cent carbon. It represents the intermediate stage in the alternation of woody matter into coal. Its colour varies from dark to black brown. It is found in Palna of Rajasthan, Neveli to Tamil Nadu, Lakhimpur of Assam and Karewa of Jammu and Kashmir.
This is the first stage of transformation of wood into coal and contains less than 35 per cent carbon. It is seldom sufficiently compact to make a good fuel without compressing into bricks. Left to itself, it burns like wood, gives less heat, emits more smoke and leaves a lot of ash after burning.