Carbon and Fossil Fuels

Biofuels are fuels which are in some way derived from biomass. The term covers solid biomass, liquid fuels and various biogases and also denotes biodiesel, bioalcohol and biogasoline. More advanced and efficient conversion technologies now allow the extraction of biofuels from materials such as wood, crops and waste material. 

Bagasse, the fibrous residue left after crushing sugarcane, is commonly used as fuel in sugar mills and as a raw material for paper production.

Natural gas is primarily composed of methane, with methane content typically ranging from 50-90% of the total composition. The remainder consists of other hydrocarbons like ethane, propane, and butane, along with impurities.

Depending on the amount of carbon, moisture and volatile matter, coal can be classified into the following varieties:

Coal is called black gold because it is black in colour and it is costly too. It is used in wide range of industrial applications and creates a positive impact on the economic development of the country. Thus it's value is compared with that of Gold.

• Lignite is a low grade brown coal, which is soft with high moisture content.
• Bituminous coal is the most popular coal in commercial use. 
  
• Anthracite is the highest quality hard coal.
  
• Magnetite is the finest iron ore with a very high content of iron up to 70 per cent. 
  

• Type of coal that is used commercially is bituminous coal.  Bituminous coal or black coal is a relatively soft coal containing a tar like substance called bitumen.
  
• This coal is graded based on plasticity, moisture content, volatility and ash content.
  
• Plasticity is essential for the production coke which is useful in making fuel gases like producer gas etc.
  
• Volatility is essential for steel making and power generation.
  

The most superior quality coal is anthracite. It has highest carbon content with 92.1% to 98% carbon. It ignites with difficulty and burns with smoke. China accounts for major production worldwide. It has fewest impurities and highest calorific value after graphite.

Anthracite is the best quality of coal with least ash content. Anthracite is a hard, compact variety of mineral coal that has a high luster. It has the highest carbon count and contains the fewest impurities of all coals, and has the highest calorific content as compared to other types of coals such as bituminous coal and lignite.

Haematite is a reddish-black mineral and an important ore of iron. It has a high iron content of 70 percent. It can be found in areas of volcanic activity or hot springs. Much hematite occurs in a soft, fine-grained, earthy form called red ochre.

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.