Important topics covered in Coal and petroleum notes:
- Introduction
- Natural Resources
- Inexhaustible Natural Resources
- Exhaustible Natural resources
- Coal
- Petroleum
- Natural Gas
- Limited Natural Resources
Introduction:
- In our day to day life, we use various materials to fulfil our needs.
- Some of them are naturals while others are artificial/man-made resources.
- Some example of natural resources are:
| Natural Resources | Man-made Resources |
| Silk | Clothes |
| Wood | Paper |
| Leather | Shoes |
| Rubber | Tyre |
| Fur | Pillow |
| Fabrics | Suit |
Natural Resources:
- The resources which are present in nature and is used by living organisms in various ways are called natural resources.
- These resources can be exploited for economic gain.
- The raw material for the food we eat, the clothes we wear is obtained from natural resources.
Types of natural resources:
There are two types of natural resources. They are:
- Inexhaustible resources
- Exhaustible resources
Inexhaustible resources:
- The resources which are never-ending and will not be depleted even after continuous usage are inexhaustible resources.
- These resources are available in large quantities in air.
- Sunlight and air are some examples.
Exhaustible resources:
- The resources which are present in a limited amount and can be depleted after continuous usage are said to be exhaustible resources.
- Overexploitation of exhaustible resources can lead to a higher rate of depletion.
- Coal, petroleum and minerals are some examples of exhaustible resources.
Fossil fuels
- Dead and decayed remains of organisms which are more than 10,000 years old are called fossils.
- Those substances which bums in air to produce energy without releasing harmful gases in large quantities are said to be fuels.
- The formation of coal and petroleum possess the same reason. So these are said to be fossil fuels.
Calorific value of fuels:
- The amount of heat liberated by complete burning of a unit mass or volume of fuel is said to be calorific value of the fuel.
- To find out the calorific value of liquid or gaseous fuels, volume of fuel is considered while for solid fuels mass of fuel is considered.
- Its unit is KJ/Kg.
- Calorific value = \(\frac{Amount\:of \:liberated\: heat\: energy}{Total\:mass\:of\:fuel}\)
Features of ideal fuel:
- Possess high calorific values.
- Pollution free by not releasing any harmful gases
- Cost-effective
- Easily available
- Easy to handle and transport and store.
- Moderate ignition temperature
- Rate of combustion should also be moderate.
Coal
- It is quite hard and stone-like substance.
- Coal appears black in colour.
- It is of great use since times.
- We use coal to heat a substance, cook food, run trains, in thermal power plants to produce electricity etc.
History of coal:
- Millions of years ago on the earth there were only forest and grasslands.
- Due to natural calamities, like floods, earthquakes the forests are buried under the soil.
- Above the dead plants, layers of soil were formed.
- As dead plants went deeper and deeper under the soil they got compressed.
- The excess temperature and pressure produced on these materials converted it into coal.
Carbonisation
- The process of conversion of dead plants vegetation into coal is said to be carbonization.
- Coal is mainly composed of carbon as on burning it releases carbon and its product.
Uses of coal
- Earlier it was used as fuel in steam engine.
- Thermal power plants use coal as fuel.
- Some households, dhabas still uses coal as the kitchen fuel.
Products of coal:
Some of the widely used products of coal are:
Coke:
- Coke is the form of coal which is hard, porous and black in colour.
- It is said to be the purest form of carbon.
- It is used in extraction of metals and manufacturing of steel.
Coal Tar:
- It is thick black liquid.
- It bears unpleasant smell.
- It is mixture of different substances.
- Synthetic dyes, explosives, drugs, perfumes, plastics, paints, roofing materials, etc. are prepared from Coal tar.
- Naphthalene balls for keeping insects away are also made from Coal tar.
- A form of coal tar i.e. bitumen is used for metalling of roads.
Coal Gas:
- Coal gas is mid material obtained between the process of obtaining coke from coal.
- It is used as fuel in many industries which are situated near coal mines.
- Earlier coal gas was used in London for lightning process but now it is used for heating purpose rather than lightning process.
Petroleum:
- Petroleum is a dark oily liquid.
- It is a mixture of various substances, like petroleum gas, diesel, petrol, paraffin wax, lubricating oil, etc.
- Earlier several organisms lived in sea.
- When they died their remains got settled at the bottom of the sea.
- The layers of clay deposited over it.
- In the absence of air with excess of temperature and pressure converted them to petroleum.
Refining of petroleum:
- The process of separating its constituents (petrol, diesel, wax etc.) from petroleum is said to be refining.
- Refining is done in petroleum refinery.
- Petrochemicals are useful substances are obtained from petroleum and natural gas.
- Detergents, polythene, fibres (nylon, polyester, acrylic etc.) and other artificial plastics are manufactured from petrochemicals.
- Due to the great commercial importance of petroleum, these are termed as “black gold”.
Uses of petroleum and its constituents:
The uses of different constituent of petroleum are listed below;
- Liquid Petroleum Gas (LPG): It is the main source of fuel in household and in some industries.
- Petrol: Automobiles uses it as a fuel and also used in dry cleaning.
- Diesel: It is used as a fuel for heavy machinery like rail engine, factories machines etc.
- Kerosene: It is mainly used in lamps and for jet aircraft.
- Paraffin wax: It is used in ointments, candles, cosmetics, Vaseline etc.
- Lubricating oil: For lubricating machinery lubricating oil is used.
- Bitumen: Used in metalling roads.
Natural gas:
- Millions of years ago natural gas was formed.
- Microscopic sea plants and animals died & got buried under the mud.
- Under anaerobic conditions, these plants and animals changed to natural gas.
- Natural gas mainly contains methane with 85% composition.
- 10% of it is ethane and 3% butane is present in it.
- When Natural Gas is compressed at high pressure then gets converted into compressed natural gases.
- It is ideal fuel with a calorific value of 55Ktj/g.
Uses of Natural gas:
- It is also used for power generation.
- Because of its less pollution measure, it is used in vehicle as fuel.
- It can easily be transported from one place to another through pipeline.
- It is also used as the beginning material for manufacturing of fertilizers.
Conservation of natural resources:
- It took millions of years for the dead organisms to get converted into coal, petroleum or natural gas.
- We have limited known resources.
- These resources are exhaustible.
- It is our responsibility to use them as less as possible.
- To fulfil our energy requirement, we must look for alternative sources of energy such as solar energy, tidal energy, wind energy, etc.
- Limited usage of these resources will save our earth from pollution, which will decrease the risk of Global warming.