There are so many materials catering to our various needs on a daily basis. We drink water, eat food, breathe air, go to school, etc. All these things are available to us, but are all free of cost and readily accessible without fear of being depleted one day.
No. Not everything is readily available to us. For instance, sunlight, air, etc are resources which we find in abundance and it won’t be depleted any time soon. Hence, these resources are called Inexhaustible natural resources.
Other resources are created in very limited quantities and it takes a very long time for such resources to be replenished. Such resources are known as exhaustible natural resources. Ex: coal, petroleum, minerals, natural gas, etc.
Let us briefly understand a few of these exhaustible natural resources.
Coal and Petroleum
Coal and petroleum are formed as a result of degradation of ancient plant life which lived millions of years ago. These dead plant matter started to pile up, eventually forming a substance called peat. Over time, heat and pressure from geological processes transformed these materials into coal. Since these are formed from essentially fossils, they are also known as fossil fuels.
How Is Coal Formed?
Formation of coal dates back to millions of years ago, when the earth was covered only with vast moist forests, having huge trees, shrubs, ferns, etc. These plants underwent their life cycle and withered away, eventually falling back to the ground, most of which were swamps. New plants replaced them, they underwent a life cycle and the whole process continued repeatedly over the years, as a result of which the earth bed started accumulating all these dead plants.
This gave rise to a very thick layer of dead decomposed matter packing down plant matter washing away all the decayed matter. Physical and chemical changes took place as a result of heat and temperature extracting out all oxygen leaving the plant layers with carbon-rich content, thus resulting in the formation of coal over a period of time.
Types of Coal
Coal can be divided into four types, based on its carbon content and ignition rate. In this section, we shall learn about the stages through which coal is formed.
- Peat: Peat is a heterogeneous mixture of partially decomposed organic matter that has accumulated in a water-saturated environment in the absence of oxygen. Peat is used for its highly absorbent property towards fuel. The carbon content in peat is less than 60%.
- Lignite: When peat gets transformed into a rock, it forms lignite. It is mainly used for electric power generation. It has a carbon content of nearly 60% – 70%.
- Bituminous: When lignite is subjected to high temperature and pressure, the process of organic metamorphism takes place, where the oxygen and hydrogen content of the matter decreases, thus increasing the carbon content. The carbon content of bituminous coal ranges from 77-87%. It is used as a fuel in steam-electric power generation and for heat and power applications in manufacturing industries.
- Anthracite: Anthracite is considered the highest quality of coal. It has a carbon content of 87% or more. It is hard and glossy in nature and has the highest heating value. It is mainly used for residential and commercial purposes.
Petroleum
Petroleum is a fossil fuel that naturally occurs in the liquid form created by the decomposition of organic matter beneath the surface of the earth millions of years ago. These fossil fuels are then refined into usable substances such as petrol, kerosene, etc. It is formed by the combination of hydrocarbons and other substances, mainly sulphur. When first collected in its natural form, it is termed as crude oil. This substance is generally characterized by a brownish-black colour. Although, it can also differ between red to pale yellow or even colourless. Its thickness (viscosity) varies from nearly solid tar-like consistency to low viscosity, almost like water.
Refining petroleum thus obtained yields many useful products. Let’s have a look at them.
Products of Petroleum
Petroleum products are obtained as a result of refining crude oil in oil refineries. There are numerous products that are created from petroleum and its by-products. A study reveals that by-products of petroleum alone provides scope to obtain 6000+ new products, to name a few, fertilizers, perfumes, flooring, insecticides, soaps, vitamins, petroleum jelly, etc.
A few of the products obtained from petroleum are:
- Gasoline
- Diesel oil
- Kerosene
- Tar
- Heavy fuel oil
- Petroleum coke
- Lubricants
- Special Naphthas
- Paraffin wax
- Aviation Gasoline
Uses of Petroleum
Petroleum is one of the most important and widely used fuels in today’s time. Some of its advantages are:
- These are transportation fuels, i.e, via air, water or land.
- Diesel is used to power turbines for the production of electricity in large scale industries.
- Oil is used to produce electricity at homes and shops.
- Oils help lubricate different types of high-end machines used in different industries, hospitals, etc.
- Kerosene is used for domestic purposes at home.
- Used by chemical industries to produce plastic, dyes, paints, synthetic rubber, pesticides, perfumes, etc.
Uses and Advantages of Fossil Fuels
Fossils represent the remains or traces of once-living organisms. Broadly, the four types of fossils are: Body, Molecular, Trace & Carbon Fossils. Fossil fuels are used to fuel cars and aeroplanes, power electricity plants, make medicines, cosmetics, plastics, synthetic fibres and lubricants and also in the manufacture of products for everyday use such as toothpaste, tires etc.
Disadvantages of Fossil Fuels
Environmental hazards
When fossil fuels are burnt, carbon dioxide is released, which is one of the primary gases responsible for global warming. The rise in the temperature of Earth, melting of polar ice caps and flooding in low-lying areas are the major consequences.
Environmental hazards due to Fossil fuels
Acid Rain
Sulphur dioxide is released when fossil fuels are burnt. It is one of the main causes of acid rain, which results in the destruction of crops and monuments made up of marble and bricks.
Destruction of monuments due to acid rain
Impact on aquatic life
Oil spills resulting from the drowning of oil tankers and ships cause water pollution in seas and oceans. This, in turn, results in the destruction of aquatic life and creates an imbalance in the ecosystem.
Oil spill
Non-renewability
The reserve for fossil fuels is limited, and they are being extracted at an exorbitant rate and are expected to be finished in the next 30-40 years.
&
Win
0 Comments