Coal and Petroleum - Comprehensive Study Notes
Introduction
Daily, we require various types of materials for our basic needs.
Resources available on Earth and energy from the sun are necessary to meet the basic requirements of all life forms.
Many materials are found in nature, while others are made by human efforts.
Natural materials: Energy from the Sun, air, water, minerals, forests, wildlife, trees, coal, petroleum, natural gas.
Man-made materials: Synthetic fibers, petrol, diesel, kerosene, biogas, synthetic gas.
Natural resources: Oil, coal, sand, air, minerals, natural gas, soil, trees, water, animals, birds, fish, and plants.
These resources are vital for sustaining life and driving economic activities.
Natural resources are used to make food, fuel, and raw materials for the production of goods.
Understanding the origins and uses of these resources is essential for their sustainable management.
Learning New Words
Coal: A fossil fuel found in deep mines beneath the surface of the earth.
Coal is a readily combustible black or brownish-black sedimentary rock usually occurring in rock strata in layers or veins called coal beds or coal seams.
Coal-gas: A mixture of hydrogen, methane, and carbon monoxide; an excellent fuel.
Coal gas is made by heating coal in the absence of air.
Coal-tar: A black, thick liquid with an unpleasant smell, used on the surface of metalled roads.
Coal tar is a viscous black liquid produced from the destructive distillation of coal.
Coke: A tough, porous, black substance that burns without smoke.
Coke is the solid carbonaceous material derived from destructive distillation of low-ash, low-sulfur bituminous coal.
Destructive distillation: The process of heating coal in the absence of air (oxygen).
Destructive distillation of organic material is the thermal decomposition of organic material by heating it in the absence of air or oxygen.
Fossil fuels: Exhaustible natural resources (coal, petroleum, and natural gas) formed from the dead remains of living organisms (fossils).
Fossil fuels are formed from the buried remains of dead plants and animals that were exposed to heat and pressure in the Earth's crust over hundreds of millions of years.
Natural gas: The fossil fuel that usually occurs above the surface of petroleum deposits.
Natural gas is a naturally occurring hydrocarbon gas mixture consisting primarily of methane, but commonly includes varying amounts of other higher alkanes, and sometimes a small percentage of carbon dioxide, nitrogen, hydrogen sulfide, or helium.
Petroleum: A dark brown and viscous crude oil with a characteristic foul smell.
Petroleum is a naturally occurring, yellowish-black liquid found in geological formations beneath the Earth's surface, which is commonly refined into various types of fuels.
Petroleum refining: The process of separating the different constituents/fractions of petroleum.
Petroleum refining is the process of separating the many hydrocarbons that make up crude petroleum into various components, called fractions, by taking advantage of the differences in boiling points of the components.
Categories of Natural Resources
Natural resources are classified into two main categories based on their availability.
Inexhaustible Natural Resources
Resources present in unlimited quantity and not likely to get exhausted by human activities.
These resources are continuously replenished by natural processes.
Examples: sunlight, water, air, soil.
Sunlight drives photosynthesis, water sustains life, air provides oxygen, and soil supports plant growth.
Exhaustible Natural Resources
Resources present in limited quantity and likely to get exhausted by human activities.
These resources require millions of years to form and are consumed at a much faster rate than they are created.
Examples: minerals, forests, wildlife, and fossil fuels (coal, natural gas, and petroleum).
Minerals are mined, forests are logged, wildlife is hunted, and fossil fuels are burned for energy.
These resources can be maintained longer if used judiciously and replenished.
Conservation efforts and sustainable practices can extend the lifespan of these resources.
Conserving Natural Resources
Recycling helps conserve natural resources by collecting wastes and processing the materials for reuse.
Recycling reduces the need for raw materials and lowers energy consumption.
Examples:-
Recycling paper saves trees.
Each ton of recycled paper saves approximately 17 trees.
Aluminum cans can be recycled into new aluminum products.
Recycling aluminum requires only 5% of the energy needed to make new aluminum.
Used motor oil can be cleaned and reused.
Recycling motor oil prevents pollution and conserves a valuable resource.
Limitations: Recycling cannot solve all problems related to natural resources (e.g., oil spills).
Some environmental damages are irreversible, highlighting the need for prevention.
Non-renewable resources: Exhaustible natural resources that cannot be replaced at all or within a reasonable time.
Once these resources are depleted, they are gone forever.
Fossil fuels (petroleum, natural gas, and coal) are examples of exhaustible natural resources that accumulated over millions of years; supplies are estimated to last only one or two centuries.
The current rate of consumption far exceeds the rate of formation.
In contrast, nuclear power from hydrogen fusion, solar, wind, and wave energy are considered inexhaustible resources.
These alternative energy sources offer a sustainable path for the future.
Soil, water, some minerals, and living organisms are renewable resources with a natural capacity to reappear through material cycles and reproduction.
These resources are vital for maintaining ecological balance and supporting life.
The rate of depletion balances the rate of reappearance, maintaining life for millions of years.
Sustainable management practices are essential to ensure this balance continues.
Lack of recycling and replenishment makes fossil fuels (coal, petroleum) and some minerals (silver, gold, copper, phosphorus, mercury, tin) non-renewable.
These materials are finite and require responsible usage.
Renewable Resources
Useful resources of nature that can be renewed by various natural means.
Renewable resources are replenished through natural processes at a rate comparable to their consumption.
Include both living and non-living resources.
This category encompasses a wide range of resources, from forests and wildlife to water and solar energy.
They have natural recycling and can be maintained indefinitely if used properly.
Sustainable management practices are crucial for ensuring the long-term availability of these resources.
Examples: Wood, biogas, groundwater, forests, hydel power, solar energy, wind energy.
These resources provide a variety of benefits, including energy, materials, and essential ecosystem services.
Non-renewable Resources
Resources that cannot be renewed or regenerated naturally.
These resources are finite and cannot be replenished within a human lifespan.
Include non-living resources only.
This category primarily consists of minerals and fossil fuels.
They do not have any immediate natural recycling and cannot be maintained for long.
Once these resources are depleted, they are essentially gone.
Examples: Coal, petroleum, natural gas, metals.
These resources are essential for modern society but require careful management and conservation.
Coal
Coal is a fossil fuel, hard and black, found in deep mines and extracted by mining.
Coal is primarily used for electricity generation and industrial processes.
In India, coal mines are mainly in Bihar, Odisha, Madhya Pradesh, and West Bengal.
These states are rich in coal reserves, which support a significant portion of India's energy needs.
Uses: fuel to cook food, produce steam in railway engines, generate electricity in thermal power plants, and fuel in various industries.
Coal serves as a versatile energy source with a wide range of applications.
It is considered the backbone of our national economy.
The coal industry plays a crucial role in supporting economic growth and development.
Composition: A mixture of free carbon and compounds of carbon and oxygen with small amounts of sulfur and nitrogen.
The specific composition of coal varies depending on its grade and origin.
Formation: Formed from the decomposition of trees, bushes, and plant life buried deep beneath the earth millions of years ago due to floods, earthquakes, cyclones, and storms.
The formation of coal requires specific geological conditions and a long period of time.
High temperature and pressure inside the Earth caused gradual decomposition in the absence of oxygen.
These conditions facilitate the chemical transformations necessary for converting organic matter into coal.
The slow process of conversion of vegetable matter into coal is called carbonization.
Carbonization is a complex process that involves the removal of water and other volatile compounds from the organic matter.
Intermediate products formed during carbonization: Peat (60% carbon), Lignite (67% carbon), Bituminous (88% carbon), and Anthracite (96% carbon).
These different grades of coal vary in their carbon content, energy density, and other properties.
Activity 2: Destructive Distillation of Coal
Objective: To obtain products from coal in the laboratory by heating coal powder in a hard glass test tube.
This experiment demonstrates the process of destructive distillation and the valuable products that can be derived from coal.
Procedure: Set up the apparatus as shown in Figure 3.2, which includes a hard glass test tube with coal powder, a single-holed rubber stopper, a glass tubing, a clamp stand, and another test tube containing water fitted with a two-holed stopper. Connect the test tubes, heat the tube containing coal strongly, and observe the escaping heavy vapors.
The setup allows for the collection and observation of the various products formed during the destructive distillation of coal.
Observations: Some vapors condense in water as coal-tar at the bottom of the tube, and some escape as coal-gas. Coal-gas catches fire when a burning matchstick is brought near the outlet tube.
These observations provide evidence of the different chemical compounds present in coal and their properties.
Results: By the destructive distillation of coal, products obtained are coke, coal-tar, coal-gas, and ammonium hydroxide (ammoniacal liquor).
These products have various industrial applications and contribute to the economic value of coal.
Products of Destructive Distillation
Coke
A clean, light fuel produced when coal is strongly heated in an airtight oven.
Coke is a carbon-rich residue that is used as a reducing agent in various industrial processes.
Contains more than 90% carbon and is porous and black.
The high carbon content and porous structure make coke an efficient fuel.
Used in the iron and steel industries.
Coke is essential for the production of iron and steel, where it acts as a reducing agent to remove oxygen from iron ore.
Seldom used as a fuel due to valuable extraction.
The valuable compounds extracted from coal make coke a more economical choice for industrial applications.
Used to prepare calcium carbide for plastics.
Calcium carbide is an important precursor for the production of various plastics and other chemicals.
Coal-tar
A black, oily material resulting from the destructive distillation of coal.
Coal tar is a complex mixture of aromatic hydrocarbons, phenols, and other organic compounds.
Further distillation yields fractions like light oil, middle oil, heavy oil, etc.
These fractions have different boiling points and are used for various purposes.
The residue is called pitch, used on the surface of metalled roads.
Pitch is a viscous, black material that provides a durable and water-resistant surface for roads.
Used in dyes, explosives, drugs, synthetic fibers, pesticides, naphthalene balls, and mothballs.
Coal tar derivatives are versatile building blocks for a wide range of chemical products.
Coal-gas
Obtained as a by-product during the processing of coal to form coke.
Coal gas is a valuable energy source that can be used for heating, lighting, and other applications.
It is a mixture of hydrogen (), methane () and carbon monoxide ().
These gases are all combustible and contribute to the energy content of coal gas.
Used as a fuel in the coal processing plant (converting coal into coke).
Coal gas can be used to power the equipment and processes involved in coal processing.
First used for street lighting in London in 1810 and New York around 1820.
Coal gas played a significant role in the development of urban infrastructure and public lighting.
In India, it was used for domestic cooking, heating, and lighting in homes, factories, and streets.
Coal gas provided a convenient and affordable energy source for various applications.
Now mostly used as a source of heat in industries.
Coal gas is still used in some industrial processes where a high-temperature heat source is required.
Ammoniacal Liquor
Used in the industry to manufacture fertilizers.
The ammonia in ammoniacal liquor can be converted into various nitrogen-based fertilizers.
Petroleum
A greenish-brown flammable liquid found underground, trapped between rocks.
Petroleum is a complex mixture of hydrocarbons with varying molecular weights.
A fossil fuel consisting of hydrocarbons mixed with oxygen, sulphur, nitrogen, and other elements.
The specific composition of petroleum depends on its origin and geological history.
Formation is believed to be derived from ancient organic material converted by bacterial action, heat, and pressure.
Petroleum formation is a slow and complex process that takes millions of years.
Formed from the remains of microorganisms and tiny plants living in the sea millions of years ago.
These organisms accumulated in sediment and were gradually transformed into petroleum by geological processes.
Remains sank to the bottom of the sea, covered with sand and clay, and decomposed to form petroleum due to chemical effects of heat, pressure, and bacterial catalytic action.
The specific conditions of temperature, pressure, and bacterial activity are crucial for petroleum formation.
Petroleum is trapped between layers of non-porous rocks.
These rock layers prevent the petroleum from escaping to the surface.
Natural gas accumulated above the surface of petroleum oil during the formation of petroleum.
Natural gas is often found in association with petroleum deposits.
Oil and gas are lighter than water and move upward, stopped by overlying impervious rocks.
This buoyancy causes the petroleum and natural gas to migrate upwards until they are trapped by impermeable rock layers.
Petroleum is found mixed with salt, rock particles, and water, hence called crude oil.
Crude oil must be refined to separate the valuable components from the impurities.
Natural gas occurs above the surface of petroleum, confined under high pressure by the upper rock.
The high pressure of natural gas can be used to drive turbines and generate electricity.
Obtained by drilling a hole in the Earth's crust where its occurrence is predicted by a preliminary survey.
Geological surveys are used to identify potential petroleum deposits.
Natural gas comes out first under high pressure, followed by petroleum. Crude oil is then pumped out of the well.
The natural pressure of the reservoir drives the initial flow of natural gas and petroleum.
Refining of Petroleum
Crude petroleum from oil wells consists of a mixture of hydrocarbons with salt, water, and earthly particles.
Crude oil is a complex mixture of thousands of different hydrocarbons.
Crude oil cannot be used as such, so it is purified (or refined) to obtain more useful components.
Refining separates the different hydrocarbons based on their boiling points.
The process of separating crude petroleum into more useful components is called refining, carried out in a petroleum refinery.
Petroleum refineries are large industrial complexes that use various processes to refine crude oil.
The method used in refining is called fractional distillation, done in a fractionating tower.
Fractional distillation is a physical process that separates the different hydrocarbons based on their boiling points.
Crude oil is heated to about 400°C in a furnace; the vapors formed are passed into a tall Fractionating Tower.
The temperature of the furnace is carefully controlled to ensure efficient vaporization of the crude oil.
Hydrocarbons with the highest boiling points condense first near the base of the fractionating tower.
These hydrocarbons are typically heavy oils and waxes.
As the vapor rises, hydrocarbons with lower boiling points condense at different heights, separated into different fractions.
The different fractions are collected at different levels of the fractionating tower.
Table 3.1 lists the fractions of petroleum with their boiling ranges and uses:-
Refinery Gas: Boiling range below 20°C. Use: (i) As a fuel in homes (in the form of CNG) and in industry. (ii) To manufacture hydrogen required in the fertilizer industry and carbon needed in the rubber industry.
Refinery gas is a mixture of light hydrocarbons, primarily methane and ethane.
Petroleum Gas: Boiling range 20°C - 40°C. Use: (i) As household fuel (in form of LPG). (ii) It is cracked to form carbon and hydrogen.
Petroleum gas is a mixture of propane and butane, commonly known as LPG.
Petrol (or Gasoline): Boiling range 40°C - 170°C. Use: (i) As a fuel for light vehicles such as cars, scooters, motor cycles, etc. (ii) As a solvent for dry cleaning.
Gasoline is a volatile and flammable liquid that is primarily used as a fuel in internal combustion engines.
Kerosene oil: Boiling range 170°C - 250°C. Use: (i) As a household fuel in wick stoves and pressure stoves. (ii) In a purified form it is used as an aviation fuel (in jet engines).
Kerosene is a thin and clear liquid that is used as a fuel in jet engines and for other purposes.
Diesel oil: Boiling range 250°C - 350°C. Use: (i) It is used to run heavy vehicles such as, trucks, buses, tractors, etc. (ii) It is used to run generators and trains. (iii) It is used to run engines for lifting groundwater for irrigation.
Diesel oil is a heavier and less volatile liquid than gasoline, used primarily in compression ignition engines.
Fuel oil: Boiling range 350°C - 400°C. Use: It is used in industrial heaters (furnaces) and boilers fuel for ships.
Fuel oil is a heavy and viscous liquid that burns to provide heat for industrial purposes.
Lubricating oil: Boiling range Above 400°C. Use: It is used for lubricating moving parts of machines.
Lubricating oil is a viscous liquid that reduces friction between moving parts.
Paraffin wax: Boiling range Above 400°C. Use: (i) It is used for making candles, boot polish, vaseline and waxed paper. (ii) It is used as grease. (iii) It is used for air proofing in laboratories.
Paraffin wax is a solid substance that is used for various purposes due to its water-repellent and lubricating properties.
Bitumen (or Asphalt): Boiling range Above 400°C. Use: (i) It is mainly used on the surface of the metalled roads. (ii) It is used for damp proofing foundations of buildings. (iii) It is also used in the manufacturing of paints.
Bitumen is a black and sticky substance that is used to bind aggregates together in asphalt pavement.
Natural Gas
A fossil fuel like coal and petroleum. It occurs above petroleum deposits or in places without petroleum deposits.
Natural gas is a versatile energy source that can be used for heating, electricity generation, and other purposes.
Mainly methane ().
Methane is a colorless and odorless gas that is the primary component of natural gas.
Natural gas should not be confused with gasoline.
Gasoline is a liquid fuel derived from petroleum, while natural gas is a gaseous fuel.
Obtained by drilling deep holes (oil wells) in the earth.
Natural gas wells are typically drilled in areas where geological surveys indicate the presence of natural gas deposits.
In India, natural gas deposits have been discovered in Tripura, Jaisalmer, offshore areas of Bombay, and in the Krishna - Godavari delta.
These regions are important sources of natural gas for India's energy needs.
Formation: Formed by the decomposition of vegetable matter buried deep below the seabed millions of years ago, carried out by anaerobic bacteria in the absence of oxygen.
The formation of natural gas is similar to that of petroleum, but it occurs under different geological conditions.
Composition: Mainly methane () with traces of ethane () and propane ().
The specific composition of natural gas varies depending on its origin and geological history.
Uses:-
As a fuel in homes and in industry.
Natural gas is used for heating, cooking, and other purposes in homes and industries.
To manufacture hydrogen, required in the fertilizer industry.
Hydrogen is used to produce ammonia, a key ingredient in nitrogen fertilizers.
To manufacture carbon, needed in the rubber industry.
Carbon black is used as a reinforcing agent in rubber products.
Conserving Natural Resources
The Earth has many essential natural resources, including water, air, soil, minerals, trees, petroleum, and natural gas.
These resources are vital for sustaining life and supporting economic activities.
Conserving these resources is crucial to ensure they do not run out.
Conservation efforts are necessary to protect the environment and ensure the long-term availability of these resources.
Energy sources, particularly oil, must be conserved, as there is a limited amount.
Oil is a finite resource that is being depleted at an alarming rate.
Scientists are exploring alternative fuels.
Alternative fuels can reduce our dependence on oil and mitigate climate change.
Efforts to reduce pollution of air and water bodies are essential for conserving plant and animal life.
Pollution can have devastating effects on ecosystems and wildlife.
These efforts will lead to a clean environment, reduced global warming, and resource availability for future generations.
Conservation efforts are essential for creating a sustainable future.
PCRA (Petroleum Conservation Research Association) in India advises people on how to save fuel and conserve the environment:
PCRA is a non-profit organization that promotes energy conservation and efficiency.
Tips for Fuel Conservation from PCRA
Avoid fast starts and sudden braking of automobiles.
Smooth driving techniques can significantly reduce fuel consumption.
Proper tuning of the engine for better mileage and maximum engine life.
A well-tuned engine operates more efficiently and consumes less fuel.
Switch off the engine at traffic lights when waiting for a longer duration.
Idling consumes fuel and contributes to air pollution.
Drive at a constant speed for better mileage and less pollution.
Consistent speed minimizes fuel consumption and emissions.
Ensure correct tyre pressure for efficient vehicle operation.
Underinflated tires increase rolling resistance and fuel consumption.
Use public transport or carpooling.
Sharing rides reduces the number of vehicles on the road and conserves fuel.
Additional Tips for Judicious Use of Natural Resources
Avoid unnecessary packaging of gifts.
Reducing packaging waste conserves resources and reduces pollution.
Reuse carrier bags.
Reusing bags reduces the demand for new plastic bags and conserves resources.
Do not dispose of chemicals or used oils down the drain or toilet.
Improper disposal of chemicals can contaminate water supplies and harm aquatic life.
Avoid burning waste, especially plastics.
Burning waste releases harmful pollutants into the air.
Walk or cycle when it is safe to do so.
Walking and cycling are healthy and sustainable modes of transportation.
Follow the 4R principle: Reduce, Reuse, Recycle, and Recover.
The 4R principle promotes responsible consumption and waste management.
Let's See It Again (Summary Points)
A natural resource is anything in, on, or above the earth that people use to meet their needs.
Natural resources provide the materials and energy that support human life and economic activities.
Inexhaustible natural resources are present in unlimited quantity and are not likely to get exhausted in the near future by human activities.
These resources are continuously replenished by