Fundamentals of boilers

1. Jinshah B S (UKFCET) Module II March 7, 2017 1 / 27
Energy conversion Devices
Boilers
UKF College of Engineering and technology
Jinshah B S
March 7, 2017

2. Outline
1 Introduction to energy conversion devices
2 Boilers
What do you meant by a boiler?
Components of a boiler
Classification of boilers
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3. Energy Conversion
Definition
Energy is the capacity of doing work.
• Energy is essential for economic development and improving the
quality of human life.
• Energy can be converted from one another in a device or in a
system.
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4. Energy Conversion
Definition
Energy is the capacity of doing work.
• Energy is essential for economic development and improving the
quality of human life.
• Energy can be converted from one another in a device or in a
system.
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5. Energy Conversion- cont..
Conversion
The energy that enters a conversion device or a process is turned into
another forms of energy, so an equal quantity of energy before and
after is maintained.
• Complete conversion of all forms except chemical energy to heat
is possible but the reverse is not.
• Due to in efficiencies such as friction, heat loss and other factors,
thermal effeciency of energy conversion is less than 100%
• Electricity is the most versatile form of energy.
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6. Energy Conversion- cont..
Conversion
The energy that enters a conversion device or a process is turned into
another forms of energy, so an equal quantity of energy before and
after is maintained.
• Complete conversion of all forms except chemical energy to heat
is possible but the reverse is not.
• Due to in efficiencies such as friction, heat loss and other factors,
thermal effeciency of energy conversion is less than 100%
• Electricity is the most versatile form of energy.
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7. So delicious!!!!!! Remember how it is made?
They all are made of steam..
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8. Next Subsection
1 Introduction to energy conversion devices
2 Boilers
What do you meant by a boiler?
Components of a boiler
Classification of boilers
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9. What do you meant by a boiler?
Definition
A Steam Boiler is a closed vessel, generally made of steel in which
steam is generated by the application of heat.
The steam boiler is also known as Steam generator
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10. What do you meant by a boiler?
Definition
A Steam Boiler is a closed vessel, generally made of steel in which
steam is generated by the application of heat.
The steam boiler is also known as Steam generator
T
he function is to convert chemical energy of fuel by combustion into
heat and to transfer this heat to water to produce steam.
Purpose for Steam generation
• For generating power in steam engines
• In the textile industry, sugar industry, chemical industries etc..
• For producing hot water.
Jinshah B S (UKFCET) Module II March 7, 2017 7 / 27

11. Next Subsection
1 Introduction to energy conversion devices
2 Boilers
What do you meant by a boiler?
Components of a boiler
Classification of boilers
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12. A typical Boiler
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13. Components of a boiler
1 Boiler shell: It is the exterior of the steam boiler, forming a case
to contain water and steam. It is made of steel bent into
cylindrical form.
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14. Components of a boiler
1 Boiler shell: It is the exterior of the steam boiler, forming a case
to contain water and steam. It is made of steel bent into
cylindrical form.
2 Grate: It is the platform, in the combustion chamber upone
which the fuel is burnt.
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15. Components of a boiler
1 Boiler shell: It is the exterior of the steam boiler, forming a case
to contain water and steam. It is made of steel bent into
cylindrical form.
2 Grate: It is the platform, in the combustion chamber upone
which the fuel is burnt.
3 furnace: It is the space above the grate and below the boiler
shell, in which fuel is actually burnt.
4 Mountings These are fittings on the boiler for its proper
functioning.
1 Waterlevel indicator
2 Pressure guage
3 Safety Valve
4 Feed Check valve
5 Steam stop valve
6 Blow-off-cock
7 Fusible plug
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16. Components of a boiler
5 Boiler accessories: These form the integral part of boiler which
are not mounted on it.
• Boiler feed pump
• Super heater
• Economizer
• Air pre-heater
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17. Water level Indicator
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18. Pressure guage
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19. Safety Valve
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20. Feed Check Valve
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21. Steam Stop Valve
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22. Blow-off-cock
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23. Blow-off-cock
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24. Fusible Plug
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25. How to select a boiler
The selection is according to;
• The rate at which steam is to be generated
• The power required and the working pressure
• The fuel and water available
• Cleaning convience, repair and operating conveniance.
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26. Next Subsection
1 Introduction to energy conversion devices
2 Boilers
What do you meant by a boiler?
Components of a boiler
Classification of boilers
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27. General classifiacation
1 According to the flow of water and hot gas
1 Firetube boiler: In firetube boilers, hit flue gas pass through tubes
which are surrounded with water.
2 Water tube boilers: Water circulates through a large number of
tubes and hot gases pass around them.
2 According to the axis of shell
1 Vertical boiler. CochranBoiler
2 Horizontal boiler. Babcock and Wilcox boiler
3 Accoding to location of furnace
1 Externally fired boiler. Water tube boilers are always extrenally
fired
2 Internally fired boiler. Furnace is an integral part.
4 According to application
1 Stationary boiler
2 Mobile boilers.
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28. Firetube boiler
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29. Water tube boiler
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30. Defference between a water tube and fire tube
boiler
Prticulars Fire tube boiler Water tube boiler
Position of
water and
hot gases
Hot gas is inside the tube
and water outside the
tubes
Water inside the tube
and hot gas outside the
tube.
Mode of fir-
ing
Generally internally fired Externally fired
Rate of
steam
production
Lower Higher
Suitability Not suitable for large
power plants
Suitable for large power
plants
Floor area For a given power it oc-
cupies more floor area
For a given power it oc-
cupies less floor area
Operating
cost
Less High
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31. Cochran Boiler
• It is very compact and requires minimum floor area
• Any type of fuel can be used with this boiler
• Well suited for small capacity requirements
• It gives about 70% thermal efficiency with coal firing and about
75% with oil firing
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32. Babcock and Wilcox Boiler
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