Notes on Coal and Petroleum
1. Natural Resources
Natural resources are materials that occur in nature and they are divided into
inexhaustible and exhaustible resources:
- Inexhaustible Natural Resources: Resources such as sunlight and air that are unlimited and cannot be exhausted.
- Exhaustible Natural Resources: These have limited quantities and can be depleted by human activities (e.g., coal, petroleum, natural gas, forests, and minerals).
2. Coal
Formation of Coal
- Coal forms from the remains of dead vegetation, specifically in swampy areas 300 million years ago.
- The process by which this transformation occurs is called carbonisation, involving the burial of the plant material under sediment where it is subjected to heat and pressure over millions of years, turning it into coal.
- Because it is formed from living organisms, coal is classified as a fossil fuel.
Uses of Coal
- Coal is primarily used to generate electricity in thermal power plants.
- Historically, it was essential for powering steam locomotives and is still employed in various industrial processes.
- Coal can be processed into useful products such as:
- Coke: A pure form of carbon used in steel production and metal extraction.
- Coal Tar: A thick liquid used to make products such as pharmaceuticals, dyes, and synthetic chemicals. Also used in road construction (as bitumen).
- Coal Gas: A gas produced during coal processing, historically used for street lighting. It is now mainly used as a heating fuel in industries.
3. Petroleum
Formation of Petroleum
- Unlike coal, petroleum originates from marine organisms. As these organisms died, their remains accumulated on the seafloor, gradually covered by sediments, and over millions of years navigated through heat and pressure similar to coal formation.
- The term petroleum comes from the Latin petra (rock) and oleum (oil), reflecting its natural source deep underground.
Uses of Petroleum
- Petroleum is used extensively as a source of fuel:
- Petrol is utilized for light vehicles, diesel for heavy transport.
- Other petroleum products include kerosene, lubricating oils, paraffin wax, and bitumen.
- The process of refining separates these components, a crucial step in transforming crude oil into usable fuels. The refined products form highly valuable petrochemicals used in the manufacture of plastics, detergents, and fertilizers.
4. Natural Gas
- Natural gas is composed mostly of methane and is recognized for being a cleaner-burning fossil fuel.
- It is easily transportable, often supplied as compressed natural gas (CNG) for use in vehicles, which makes it a less polluting alternative to traditional fossil fuels.
5. Environmental Considerations
- Both coal and petroleum are non-renewable resources, and their reserves are limited. Their combustion contributes significantly to air pollution and global warming.
- There are numerous reserves of these resources across the globe, including India, where oil fields exist in Assama and Gujarat, while natural gas deposits are identified in Tripura and Maharashtra.
- The chapter emphasizes the importance of using these fossil fuels judiciously through conservation initiatives and improved energy efficiency practices.
The Role of Petroleum Conservation Research Association (PCRA)
- The PCRA promotes various methods to save fuel, such as driving at a steady speed and maintaining proper vehicle conditions to minimize wastage.
Conclusion
The understanding of coal and petroleum is crucial not only for practical applications such as energy and materials production but also for addressing their environmental impacts. Proper conservation and management practices can extend their availability and reduce the ecological footprint associated with their use.