Petroleum: Source, Formation and Classification

Petroleum is a fossil fuel, formed from trees plants, bacteria and algae. Over million years, under the earth, due to high heat and pressure, that fossils converted into high carbon usable fuels.

Petrol comes from where? …… Do you know?

Have refueled your car? …… Ohhh No??? You must need to go or Petrol station, and refuel it. But have think about that, petrol comes from where? Petrol and petroleum oil is most important energy source in our daily life. Now a days, we can say that without petrol our life will be motionless.

Petrol is British English word, it is a fuel derived from crude oil which is used into run a SI (Spark Plugged Ignition) IC Engines, which may used to drive your car or may used in an industry. It also known as Gasoline in American English. Petroleum fuels are stable sources of energy instead of renewable energy sources (solar energy, wind energy).
Crude oil is extracted from some miles depth of earth using giant drilling machines. The reservoirs are found beneath the earth and sea surface. And then in refinery it refines by refinement process, where crude oil is transforms in Fuels like Gasoline, Diesel, Various types of gaseous products like LPG (Liquefied Petroleum Gas), CNG (Compressed Natural Gas), lubricants oil and many more by products of petroleum also.
Before discovery of mineral oils, woods and coals were the main sources of fuel. And for small purposes oil was resourced from natural resources like groundnut, and fatty oil from animals and fishes.

Do you know!!!
World’s largest refinery plant is situated in India called as Jamnagar Refinery. This refinery plant having refining capacity of 1.24 million barrel oil per day. 

It is located in Jamnagar district of Gujarat, India. This refinery is owned by Reliance Industries Limited.

Petroleum Refinery.
Petroleum Refinery.


Measuring unit for Mineral oil is Barrel. One barrel is equals to 159 liters (Approximately), and 35 Imperial gallon or 42 US gallons.

Crude oil pump.

 What is Petroleum and how it is formed?

Dark black or brown liquid (sometimes yellowish, reddish, greenish) found under the Earth surface, which known as Mineral Oil OR Crude Oil. This variation in colors depends upon mixtures of chemicals. By fractional distillation processes, it is refined into various types of fuels. Petroleum word is comes from Latin word, “Petra” becomes “rocks” and “Oleum” becomes “Oil”.  Petroleum includes solid and gaseous hydrocarbons, and crude oil. In an underground oil reservoir, amount of gas, liquid and solid depends upon sub surface conditions.

Petroleum is the mixture of various larger hydrocarbons. Crude oil contains hydrocarbons, alkanes, nitrogen, oxygen, sulphur and such amount of metals such as copper, iron, nickel etc.

Petroleum is non- renewable energy sources, like coal and natural gases. There is no any way to replace it, because it took millions years to formation under the earth layers. Once it extracted and consumed we have not any option to replacement.
To finding the alternatives of Petroleum, is so much mandatory for us, and industries having aim to find it.

Formation of Petroleum:
Petroleum is a fossil fuel, formed from trees plants, bacteria and algae. Over million years, under the earth, due to high heat and pressure, that fossils converted into high carbon usable fuels.

Million years ago due to geographical movements and devastating earthquakes, living creatures, trees and plants on the earth gone under the ground. Over years, that organic elements are compressed under heavy pressure and temperature. In absence of oxygen under the layers of earth this organic matter converted into waxy substance known as Kerogen. Over time, that Kerogen is transformed into catagenesis and this also transforms into hydrocarbon, due to high heat and pressure.
This hydrocarbon composed by Hydrogen (about 13 to 15% by weight) Carbon (about 82 to 85 % by weight) and other elements such as Nitrogen (0.3 to 0.6 %), Sulphur, and Oxygen and metals like nickel, copper, iron etc. Due to this variation, extracted crude having various petroleum products like fuel, heavy oil, light oil, gases, plastics, bituminous. While, light oil contains higher hydrocarbon instead of heavy oil. And bituminous having lesser hydrocarbons and another substances are present. So, it is always required to refining that crude oil to making useful petroleum products.


IC engine.
IC engine.


Do you know!!!
Gasoline or Petrol is also known as Motor Spirit, which is used to run IC Spark Ignition engines.


Sulphur basis classification of petroleum:

Sulphur is an impurity in crude oil. If quantity of sulphur in petroleum is less than 0.5%, it is called as “sweet”. And sulphur is more than 0.5% in petroleum, it is called as “sour”. Sulphur is harmful for machinery during refining process. It will corrode metals. And also harmful for environment. So, “sour” petroleum requires more refining instead of “sweet”. Due to that, sweet petrol having more value.

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