Tag: mineral fuels

Coal is an inflammable organic substance, composed mainly of hydrocarbons, found in the form of sedimentary rocks and capable of being used as fuel to supply heat or light or both. It is formed when sub merged vegetation remains under great pressure for a considerably long time. 

Bituminous coal or black coal and Lignite coal are relatively soft. Bituminous is a higher quality than lignite coal but of poorer quality than anthracite.

Anthracite is a best quality coal. Its carbon content is 90% to 95%. Its burns slowly and great heat, with very little smoke.

Lignite is a lower grade coal and contains about 40% to 60% carbon. It has low heating power and emits smoke. Its colour varies from dark to black brown. 

Peat is the first stage of transformation of wood into coal and contains 30% to 45% carbon, sufficient volatile matter and lot of moisture. Its heating capacity is low and normally used as domestic fuel. 

Peat is the first stage of transformation of wood into coal and contains less than 40% to 55% carbon, sufficient volatile matter and lot of moisture. Its heating capacity is low and generally used as domestic fuel.

Lignite is a lower grade coal and contains about 40 to 55% carbon. It has low heating power and emits smoke. Its colour varies from dark to black brown.  

The yellow colour flame is seen when bituminous coal is burnt due to incandescence of very fine soot particles that are produced in the flame. This type of flame only burns at around 1,000 °C. Depending on the lighting, you may have actually seen the soot rising from the flame.

Anthracite is the best quality coal. It burns slowly and generates great heat, with very little smoke. Its carbon content is 80 to 95%. Only 5% of the world's coal is of this type.

Bituminous coal contains moisture up to approximately 17 percent. About 0.5 to 2 percent of the weight of bituminous coal is nitrogen. Its fixed carbon content ranges up to approximately 85 percent, with ash content up to 12 percent by weight.