some basic of fuel

1. L. D. COLLEGE OF
ENGINEERING
RUBBER TECHNOLOGY
Sub:- THERMODYNAMICS OF
ELASTOMERS & POLYMERS

3. Introduction
The Formation of Fuel
 Solar energy is converted to chemical energy through
photo-synthesis in plants.
 Energy produced by burning wood or fossil fuels
 Fossil fuels: coal, oil and natural gas
=>) We know that, in most of the world today, wood is not the main
source of fuel. We generally use natural gas or oil in our homes, and
we mainly use oil and coal to heat the water to produce the steam
to drive the turbines for our huge power generation systems. Coal,
oil, and natural gas are often referred to as fossil fuels.

4. Types of Fuel
 Usage
• Used extensively in industrial applications
 Examples
• Furnace oil
• Light diesel oil
• Petrol
• Kerosene
• Ethanol
• LSHS (low sulphur heavy stock)
Liquid Fuels

5. Types of Fuel
Liquid Fuels
 Density
• Ratio of the fuel’s mass to its volume at 15 oC,
• kg/m3
• Useful for determining fuel quantity and quality

6. Types of Fuel
 Sulphur content
• Depends on source of crude oil and less on the
refining process
• Furnace oil: 2-4 % sulphur
• Sulphuric acid causes corrosion
 Ash content
• Inorganic material in fuel
• Typically 0.03 - 0.07%
• Corrosion of burner tips and damage to materials
/equipments at high temperatures
Liquid Fuels

7. Types of Fuel
 Storage of fuels
• Store in cylindrical tanks above or below the ground
• Recommended storage: >10 days of normal
consumption
• Cleaning at regular intervals
Liquid Fuels

8. Types of Fuel
Solid Fuels
 Coal classification
• Anthracite: hard and geologically the oldest
• Bituminous
• Lignite: soft coal and the youngest
• Further classification: semi- anthracite, semi-
bituminous, and sub-bituminous

9. Types of Fuel
Solid Fuels
 Physical properties
• Heating or calorific value (GCV)
• Moisture content
• Volatile matter
• Ash
 Chemical properties
• Chemical constituents: carbon, hydrogen, oxygen,
sulphur

10. Types of Fuel
Solid Fuels (Physical properties)
 Ash
• Impurity that will not burn (5-40%)
• Important for design of furnace
• Ash = residue after combustion
 Fixed carbon
• Fixed carbon = 100 – (moisture + volatile matter + ash)
• Carbon + hydrogen, oxygen, sulphur, nitrogen
residues
• Heat generator during combustion

11. Types of Fuel
Solid Fuels (Chemical Properties)
 Storage, Handling & Preparation
• Storage to minimize carpet loss and loss due
to spontaneous combustion
• Reduce carpet loss: a) a hard surface b)
standard concrete/brick storage bays
• Coal preparation before use is important for
good combustion

12. Types of Fuel
Gaseous Fuels
 Advantages of gaseous fuels
• Least amount of handling
• Simplest burners systems
• Burner systems require least maintenance
• Environmental benefits: lowest GHG and other
emissions

13. Types of Fuel
Gaseous Fuels
 Natural gas
• Methane: 95%
• Remains 5%: ethane, propane, butane, pentane,
nitrogen, carbon dioxide, other gases
• High calorific value fuel
• Does not require storage facilities
• No sulphur
• Mixes readily with air without producing smoke or
soot

14. Types of Fuel
Gaseous Fuels
 Liquefied Petroleum Gas (LPG)
• Propane, butane and unsaturated, lighter C2
and heavier C5 fractions
• Hydrocarbons are gaseous at atmospheric
pressure but can be condensed to liquid state
• LPG vapour is denser than air: leaking gases
can flow long distances from the source

15. Combustion Calculation
There are mainly three types of measuring
calorific value of fuel by several technology as
per below;
 Bomb calorimeter
 Junker’s gas calorimeter
 Boy’s gas calorimeter

16. Performance Evaluation
• Combustion: rapid oxidation of a fuel
• Complete combustion: total oxidation of fuel (adequate
supply of oxygen needed)
• Air: 20.9% oxygen, 79% nitrogen and other
• Nitrogen: (a) reduces the combustion efficiency (b) forms
NOx at high temperatures
• Carbon forms (a) CO2 (b) CO resulting in less heat
production
Principles of Combustion

17. Performance Evaluation
Stochiometric calculation of air
required
 Stochiometric air needed for combustion of furnace oil
 Theoretical CO2 content in the flue gases
 Actual CO2 content and % excess air
 Constituents of flue gas with excess air
 Theoretical CO2 and O2 in dry flue gas by volume