SSC Notes- Fuels

Dear Readers, we are presenting SSC CGL study material. In this post we are providing basic information about fuels.

The substances which provide heat either alone or by combining and reacting with another are called fuels. Almost all fuels have a substantial amount of carbon within themselves and produce heat on burning in air. The gaseous fuels are most suitable and preferable to solid and liquid fuels.

Water gas: This is basically a molecular mixture of carbon monoxide (CO), hydrogen (H2) and carbon dioxide (CO2), while water (H2O) and nitrogen (N2) remain as impurities.
The calorific value of water gas is more than producer gas. Water gas mixed with coal gas is used as a good fuel.

Producer gas: This is basically the mixture of carbon monoxide (CO) and nitrogen (N2), in which nitrogen and carbon monoxide are mixed by volume in the ratio of 2 : 1.

Natural gas: Natural gas is mainly composed of methane or CH4 (83%) and ethane or C2H6 (16%), which are abundantly present at the exploration sites of the petroleum substance.

Coal: Coal is a very important type of fossil fuel which is found on comprehensive level inside the earth. It is mainly composed of 60-90% free carbon and its compounds. Besides, the compounds of nitrogen, sulphur, iron etc. are also present in small amounts.
There are four types of coal on the basis of amount of carbon present in them.
1. Peat coal : 50-60% carbon
2. Lignite : 60-70% carbon
3. Bituminous : 78-86% carbon
4. Anthracite : 94-98% carbon

Peat coal is a poor-quality coal. It is produced in the first phase of extraction. Lignite coal is also called brown coal.

Bituminous coal is very soft and it is used for domestic purposes. It is about 80% of the total coal in the world.

Anthracite is the best type of coal among all. On burning the anthracite coal, no smoke is produced and extremely large amount of heat is generated. Also, the anthracite coal is obtained in the last phase of coal extraction.

Petroleum: It is a brown-black liquid which has a special type of smell. Basically, it is composed of various hydrocarbons (solid, liquid and gas) and sulphur, whose calorific value is extremely high in comparison to all solid and liquid fuels.

Liquid Petroleum Gas (LPG) and Compressed Natural Gas (CNG) are mixtures of ethane, propane and butane and their main components are normal butane and iso-butane. In domestic
gas cylinders, normal butane and iso-butane burn very quickly
and give out a good amount of heat. Actually, on increasing pressure, normal and iso- butane are compressed and consequently liquefied and used as LPG in cylinders for
domestic purposes.

Calorific value of the fuels: The calorific value of any fuel is the amount of heat obtained by the complete burning of 1 gram of the fuel in air or in oxygen. The heat produced or generated is expressed in calorie, kcal, or in Joule.