The document discusses the history and efficiency of steam-generating boilers, highlighting innovations by George Babcock and Steven Wilcox, as well as the principles of boiler efficiency and factors that affect it. It covers methods for maximizing efficiency, such as preheating feed water and using supplementary heat exchangers, along with the importance of safety devices in boiler operations. Waste heat recovery systems and various technologies for energy recovery are also outlined, emphasizing the significance of periodic maintenance and safety regulations.

1. Can anyone tell me what is this?
 Is this a Sewing machine?
 or, a Cannon?
This is a Boiler !!!

2. HISTORY
George Babcock and Steven Wilcox were two of
the founding fathers of the steam-generating
boiler. They were the first to patent their boiler
design, which used tubes inside a firebrick-
walled structure to generate steam, in 1867, and
they formed Babcock & Wilcox Company in New
York City in 1891.

3. GROUP 2| CEP,SUST

4. Presentation Overview
 Forward-thinking, flexible solutions that
save energy.
 Adding value to process by cost
reduction (lowering TCoO and improving
ROI)
 Reducing carbon footprint

5. TOPICS INCLUDED

6. Criteria to select a Boiler

8. Boiler Efficiency: (Facts vs. Reality)
 According to the 2nd law of Thermodynamics, the
greater the temperature of heat source the more
efficient is the cycle. Therefore, making the steam
temperature very high will result in a highly efficient
power plant.
 But this temperature increase has certain limitations.
The steam turbine blade materials cannot withstand
temperatures greater than 600 0C.

9. Boiler efficiency (contd.)
 One more heat exchanger is added after the steam
drum to superheat the steam and it is heated to the
maximum allowable limit (about-550 degree
Celsius).(Efficiency gain~5%)
 A clever idea to increase the power plant efficiency is
to bypass the steam completely after the first stage
and add more heat. This process is known as
reheating. A heat exchanger known as ‘reheater' is
used for this purpose. (Efficiency gain~3%)

10. Boiler efficiency (contd.)
 Superheating and reheating also helps in minimizing
MC in the steam, increasing power plant capacity.
 Another efficiency reducer of the boiler is the dissolved
O2 and CO2 in the feed water. These dissolved gases
will spoil the boiler material over time. So the feed water
is preheated by the preheater for removing the
dissolved gases. This increases the efficiency of the
boiler dramatically.

11. Step by step procedure for maximizing
efficiency:
Preheating of the
feed water.
Heating by flue gas
in economizer
Steam Drum reduces
moisture content of
steam
Superheating of
steam.
Reheating after
first stage of HP
turbine.

13. Heat balance in a
boiler
HEAT FLOW DIAGRAM

14.  Heat delivered to water = m(Hsteam - Hfeed)
where,
 Hsteam = Enthalpy of superheated steam (kJ/kg)
 Hfeed = Enthalpy of feed water (kJ/kg)
 m = amount of water produced from all sources
Heat given to steam in a boiler

15. Components of Heat Input, Q
• Lower heating value (LHV)
• Sensible heat of fuel
• Sensible heat of air
• Heat of fuel atomizing steam

16. HEAT LOSS
COMPONENTS
 Flue gas loss, Q2
 Incomplete combustion of gas,Q3
 Heat loss due to unburnt carbon, Q4
 Heat loss due to surface convection & radiation, Q5

17. HEAT BALANCE
 HEAT INPUT = HEAT UTILIZATION + HEAT LOSSES
 Q = Q1+ Q2+ Q3+ Q4+ Q5
 Q = Available heat of fuel
 Q1= Heat utilized by steam and water
 Q2= Heat lost through stack gas
 Q3= Incomplete combustion (CO,CH4,H2)
 Q4 = Unburnt carbon
 Q5 = Loss from boiler surfaces

18. Waste Heat Recovery Boiler (WHRB)
 A WHRB is an energy recovery
heat exchanger that recovers
heat from hot streams with
potential high energy content,
such as hot flue gases from
diesel generator or steam from
cooling towers or even waste
water from different cooling
processes such as in steel
cooling.
Examples of WHRB are:
1. Recuperator
2. Regenerator
3. Thermal wheels
4. Heat pumps
5. Economizer and so on…

19.  1. Recuperator : Recuperator
works as counter flow type
heat exchanger. Hot waste
gas enter the one side of the
boiler and air or gaseous fuel
enter the another side of the
boiler. Hot waste gas gives
heat to the incoming air or
gaseous fuel.

20.  2. Regenerator : Regenerator works in
two cycle and has two sets of check-
work chambers, called regenerators.
The hot waste gas enter the one set of
regenerators and gives heat to the
regenerators. Then waste gas
removed and air or gaseous fuel are
heated in the heated regenerators.
The direction of in going air or
gaseous fuel are reversed after every
25-30 minutes during which one set of
regenerators gets cooled because of
loss of heat to air or gaseous fuel and
others set of regenerators gets heated
up because of absorption of heat from
the hot waste gases.

21.  3. Thermal wheels : also
known as rotary heat
exchanger consists of a
circular honeycomb
matrix of heat absorbing
material, which is slowly
rotated within the supply
and exhaust air streams
of an air handling
system.

22.  4. Heat pumps : Heat
pumps are designed to
move thermal energy in
the opposite direction of
spontaneous heat transfer
by absorbing heat from a
cold space and releasing
it to a warmer one.

23. Economizers : Economizers are
mechanical devices intended to
reduce energy consumption, or to
perform useful function such as
preheating a fluid. Economizers
are uses in the boiler, power
plant, refrigerator and so on.

24. All boilers and domestic water heaters have a range of built-in
devices to help ensure their safe operation. Like other
components of building mechanical systems, they require
periodic maintenance to ensure proper operation. Boiler
operators and technicians should pay close attention to three
key safety devices to protect personnel, equipment, and the
facility.

25. The safety valve is the most
important safety device in a boiler
or domestic hot-water system. It
is designed to relieve internal
pressure if a range of failures
occur within the system. Although
it is simple in design and
straightforward in operation,
something as simple as corrosion
or restricted flow within the valve
and its related piping can affect its
operation.

26. Even with a functioning water-
level-control system, operators
must verify the actual level of
water in the system. Here too,
a build-up of sludge and scale
can give false level
indications.

27. An electrostatic
precipitator (ESP) is a
filtration device that
removes fine particles, like
dust and smoke, from a
flowing gas using the force
of an induced electrostatic
charge minimally impeding
the flow of gases through
the unit.
ELECTROSTATIC PRECIPITATOR (ESP) :

28. Historically, boilers were a source of many
serious injuries and property destruction due to
poorly understood engineering principles. Some
professional specialized organizations such as
the American Society of Mechanical Engineers
has developed standard and regulation code for
boiler which can prevent this type of danger.

29. References
 Energy Solution Center Inc.
http://www.energysolutionscenter.org/BoilerBurner/
 Alkan Murray Corp.
http://www.alkenmurray.com/Boilerworks.html
 Frederick M. Steingress (2001). Low Pressure
Boilers (4th ed.). American Technical Publishers.
 B. K. Sharma, Industrial Chemistry , GOEL Publishing
House, 1997.

30. Thank you .