The Fuel Notes with PDF

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Classification and Sources of Fuels

Fossil Fuels

• Petroleum: A natural fuel.
• Natural Gas: A fossil fuel; considered the cleanest fossil fuel.
• Coal: A fossil fuel.
  • Indian coal has a high ash content.
  • Coal ash contains toxic elements (e.g., arsenic, lead, mercury).
• Furnace Oil: A processed product from oil refineries.

Processed & Synthetic Fuels

• From Coal:
  • Coal Gas: A manufactured product (not natural). Major constituents: Hydrogen, Methane, Carbon Monoxide.
  • Coke: A solid carbon-rich fuel produced from coal.
  • Tar: A manufactured product from coal.
• Other:
  • Water Gas: A manufactured mixture of Carbon Monoxide (CO) and Hydrogen (H₂); not a fossil fuel.

Gaseous Fuels

• Liquefied Petroleum Gas (LPG):
  • Main components: Butane and Propane (main constituent is often Butane).
  • Indane gas is a mixture of Butane and Propane.
  • Supplied in cylinders in a liquid form.
• Biogas (including Gobar Gas):
  • Primarily consists of Methane (CH₄) and Carbon Dioxide (CO₂).
  • The ‘Gobar Gas’ system was invented by S.V. Desai.
  • The production process is Fermentation.
• Compressed Natural Gas (CNG):
  • Stands for Compressed Natural Gas.
  • Major component: Methane (CH₄).
• Piped Natural Gas:
  • Main component is Methane; can be supplied directly through pipelines.
• Liquefied Natural Gas (LNG):
  • Natural gas liquefied under extremely cold temperatures and high pressure.
• Natural Gas Liquids (NGLs): Separated from LPG; include ethane, propane, butane, and natural gasoline.
• Gas Emitted from Rice Fields: Methane (CH₄).

Fuel Properties, Quality, and Environmental Impact

Fuel Quality Metrics

• Octane Number: Measures the quality of petrol (gasoline); indicates anti-knocking properties.
• Cetane Number: Measures the quality of diesel; indicates ignition delay time.

Fuel Efficiency and Value

• Highest Fuel Value: Hydrogen has the highest energy content per unit mass compared to charcoal, natural gas, and gasoline.
• Vehicle Fuel Efficiency: Features that improve efficiency include:
  • Streamlined body (reduces air resistance).
  • Multipoint fuel injection (improves combustion).
  • Catalytic converter with exhaust (reduces emissions).

Environmental Impact

• Cleanest Fossil Fuel: Natural gas.
• Maximum Indoor Chemical Pollution: Caused by burning coal.
• Sulfur Emissions: Caused by the use of furnace oil.
• Power Plant Pollutants: Coal-fired power plants release sulfur dioxide (SO₂) and oxides of nitrogen (NOx).
• Copper Smelting Pollutants:
  • Copper slag can cause leaching of heavy metals.
  • Releases sulfur dioxide (SO₂).

Fuel Applications and Industrial Processes

Metallurgy (Blast Furnace)

• Fuel/Reducing Agent: Coke is used with two primary functions:
  1. Acts as a reducing agent.
  2. Functions as a fuel to supply heat.
• It does not act as an oxidizing agent.

Power Generation

• Furnace oil is used by some industries to generate power.

Engines

• Diesel Engine Fuel: The fuel used is a vapour of diesel and air.

Fuel Additives and Special Mixtures

Fuel Additives

• Anti-Knocking Agent: Tetraethyl Lead (TEL) was added to petrol to increase its octane rating.
• Safety Additive (LPG): Ethyl mercaptan is added to LPG to produce a stench for leak detection.
• Anti-Freeze Agent: Ethylene Glycol is used in automobile engines.

Fuel Mixtures

• Gasohol: A correct mixture of Gasoline (Petrol) and Ethyl Alcohol (Ethanol).
  • Incorrect statement: “Gasohol is a mixture of benzene and alcohol” is false.

Clarifications and Corrections

True/False Clarifications

• “The main component of the liquefied petroleum gas is methane” is FALSE.
• “Methane can be used directly for burning in homes and factories where it can be supplied through pipelines” is TRUE.

General Science Facts

• Oxygen is absent in: Kerosene. (It may be present in soil, glass, and cement).
• Fossil Fuels: Coal, petroleum, and natural gas.
• Non-Conventional Energy Source: Geothermal energy.

Incorrect Facts (from provided options)

• The first LNG terminal in India was not built in Hassan. (The first was in Dahej, Gujarat).
• Hydrocarbon Vision 2025 was not primarily about the storage of petroleum products, Euro vehicles, or the Greenhouse effect. (It was a policy for the Indian oil and gas sector.)

Storage and Handling

• LPG Cylinders: Pressure gauges are not used on domestic LPG cylinders because pressure cannot represent the quantity of gas (it remains constant until the liquid evaporates); quantity is determined by weight.
• Hydrogen Storage: Hydrogen gas can be stored for vehicle fuel by being absorbed by Hydrides at low temperatures and released by heat.

Know More About The Fuel:

• The Fuel – Old Year Questions
• The Fuel One Liner Questions & Answers