Coal and Petroleum: Learn Their Types, Formation, Effects & Importance

Although the world is aware of the harmful effects of fossil fuels, it is still too difficult to completely get rid of them. Thus, fossil fuels are still being used, the most common among them are coal and petroleum. Coal and petroleum are just two different types of carbon compounds. Both of these materials were made of organic compounds long ago in the depths of the Earth. These materials are mined today to meet the energy requirements of the human world.

This  Physics article will explain in detail about coal and petroleum.

What is Coal?

Coal is defined as a black or brown sedimentary rock (rock consisting of layers) which is combustible. It is mostly used by burning it to produce heat energy. This energy is then further converted into different forms of energy. It is a fossil fuel and mostly contains hydrocarbons. It is formed from the remains of ancient organisms.

The above image shows small pieces of coal.

The above image shows how coal is mined. The image above is specifically of an open coal mine.

Types of Coal

The coal that is available can be differentiated into three types based on their carbon content which are as follows:

Lignite

It is the coal with the lowest carbon content. The carbon content is only about 60-70 %. It is formed during the younger stages of coal formation and thus has a lower carbon content. Due to the less amount of carbon, it is not fully black in colour and is somewhat brown. Lignite is used in electricity generation and in fertilizer production. It produces around 10-20 MJ/kg when burnt.

Anthracite

It is the coal with the highest amount of carbon with an average carbon content of around 92-98 %. Due to the high amount of carbon, it is metallic black in colour and has a metallic lustre. It is a hard rock and burns with a blue and smokeless flame. This type of coal is used primarily in power generation since this type of coal produces around 26-33 MJ/kg when burnt.

Bituminous

This type of coal has an intermediate carbon content which is in the range of 85 %. This type of coal is also black or dark brown in colour. Due to the presence of a tar-like substance known as bitumen when heated, it is used in road construction. It is also used in cement manufacturing. It produces around 25-32 MJ/kg when burnt thus sometimes also used in power generation.

Petroleum

Petroleum is a black-coloured liquid which is mined from the inner layers of the Earth. It is also made up of carbon but not pure carbon. Instead, it consists of a number of hydrocarbons (compounds of carbon and hydrogen). Petroleum and its derivatives are used as a primary energy source for most all types of vehicles on the planet.

List of Petroleum Products

The petroleum that is extracted from the Earth is not the petrol that we fill in our vehicles. Rather, it is a mixture of different types of oils along with impurities. Thus, it is also known as crude oil. From this crude oil, a number of petroleum products are obtained by fractional distillation. This process takes advantage of the different boiling points of the different types of hydrocarbons in petroleum to separate them. The following are some of the petroleum products:

• Kerosene
• Tar
• Heavy fuel oil
• Lubricants
• Paraffin wax
• Aviation gasoline
• Petroleum coke

How Coal and Petroleum Are Formed?

The formation of coal and petroleum (or fossil fuels) started long ago, even before humans were there on the planet. With the death of vegetation and the wildlife of that time, the remains of these organisms used to stay on the ground itself. Some of these remains may have fallen into rivers, valleys, or places where dirt and soil used to get collected in a regular manner. In these places, the process of sedimentation occurred. In this process, new soil gets deposited upon the older ones.

Similarly, with the sedimentation of new layers, the older layers along with the remains of the dead organisms got pressed underneath them. With more and more sedimentation, the pressure exerted on these remains increased and so did the heat. Due to these remains being under such depth in the ground, oxygen was also unavailable. Under these high heat and pressure conditions, the organic remains undergo a number of chemical changes over millions of years to get converted into the fossil fuels that we use today.

Sedimentation happened not only on the land but also on the seas. With the death of the aquatic organisms, their remains fall on the seabed and get sedimented along with new layers of sand.

Conservation of Coal and Petroleum

The fossil fuels that were formed millions of years ago are not unlimited. There is only a limited quantity of them, and they cannot be made again because naturally, it takes a lot of time to form fossil fuels. Thus, the conservation of these fossil fuels like coal and petroleum is necessary.

Conservation of coal and petroleum can be done by using them in the correct way. Although we don’t handle coal outright in our daily lives, we obtain electricity which is primarily made out of coal. Thus, we should use it judgmentally and only when it is required. In this way, the wastage of energy would reduce which would also reduce the use of coal. Similarly, petroleum conservation requires the proper use of petroleum. One way to save petroleum is by carpooling while going to the office or school. The use of public transport also reduces the amount of petroleum used per person. For relatively short distances a walk can be preferred.

Harmful Effects of Coal and Petroleum

The harmful effects of coal and petroleum are the by-products which are obtained from their combustion. Upon burning coal and petroleum we obtain carbon dioxide. Naturally, carbon dioxide is present in the atmosphere due to it being produced by mostly all living organisms while respiration. However, the addition of more carbon dioxide into the atmosphere due to such combustion of fossil fuels leads to global warming and environmental pollution. The other harmful aspect of these fossil fuels is the pollution caused by the extraction of these products.

Importance of Coal and Petroleum

The importance of coal and petroleum lies in the fact that these are the primary energy providers for the human population. Coal is used for supplying electrical energy whereas petroleum products are used to run vehicles which keeps us connected.

Hope this article about coal and petroleum was able to get the concept of this topic in motion. There are many such interesting topics and their real-life applications to learn about, just download the Testbook app and start browsing to get insights on them which can clear all your concepts regarding them.