Fossil fuels are used for a variety of domestic and industrial purposes. These fuels contain high percentages of carbon and generate huge amount of energy when heated. These non-renewable sources of energy are formed as deposits within the inner layers of earth.
The remains of animals and vegetations that died millions of years ago formed the reserves of fossil fuels in different parts of the world. Fossil fuels are mostly found in three basic types namely natural gas, coal, and petroleum.
Description of Fossil Fuels
The three types of fossil fuels are obtained from different sources. These fuels are mostly produced from different types of zooplankton and phytoplankton. The transformation process of these ancient organisms took millions of years.
As per the biogenic theory, the remains of certain type of algae or plankton form natural gas after several years of transformation. Methane is the most common form of natural gas found from the inner layers of earth. Sometimes natural gas is collected from the surface of the petroleum deposits.
Owing to its low density, natural gas is normally found over the petroleum reserves. Huge reserves of only natural gas are also found in certain parts of the world. This form of fossil fuel is normally used for household purposes. It is also more environment-friendly compared to the other forms of fossil fuels.
Coal is formed from the decomposed remains of plants like moss, ferns, and the like through the process of coalification. High atmospheric pressure and temperature are some of the other conditions that are required for the formation of coal. The composition of coal depends on the nature of deposit. More than 1200 different varieties of coal are found in different parts of the world. Graphite is the most carbon-rich form of coal.
Petroleum contains different forms of hydrocarbons both in simple and complex configurations. The remains of oceanic plants and bacteria of prehistoric time formed the deposits of petroleum. It required millions of years for the entire transformation process to complete. Crude petroleum is used to produce a number of distillate fuels like kerosene, turbo-jet fuel and the like. It is also used in plastic production. Petroleum meets nearly 40 percent of the world demand of energy.