Umar Farooq authored a document about power plant chemistry that included sections on heat transfer, the steam-water cycle system, boiler types and parts, turbines, and generators. The document provided definitions and explanations of key concepts like temperature, latent heat, heat transfer methods, steam types, boiler classifications, condenser and deaerator functions, and the advantages of water tube boilers over fire tube boilers.

1. Power Plant Chemistry
Parts Of Power Plant and its Function
Prepared By : -
Umar Farooq
Chemist “A” Chemical Section
MSC ( Chemistry ) MBA ( Marketing )
umar7325@yahoo.com
107301@se.com.sa
SEC Shoaiba Jeddah
Saudi Arabia 1

3. Power Plant Chemistry
 Table Of Content
 Fundamental of Heat , Heat Transfer
 Steam Water Cycle System
 Condenser, Deaerator , Feed Tank
 Steam Generator ( Boiler )
 Types Of Boiler’s
 Parts of Boiler
 Boiler Ex auxiliaries
 Turbine
 Generator

4. Fundamental of Heat
 Heat It is common form of energy .Heat added to a body makes it
hotter removing heat cools it . Heat energy can be turned into
mechanical energy to do work.
 Temperature It describes the degree of hotness or coldness of
body .It has two units centigrade and Fahrenheit scale. Conversion
Formula C/5=F-32/9
 Calorie It is the amount of heat required to raise the temperature of
1 g of H2O through 1C*
 B.T.U It is the amount of heat required to raise the temperature of
1Lb of H2O through 1F*.
 C.H.U It is standard abbreviation of centigrade heat unit.
 Sensible Heat: The heat shown by the thermometer or the heat
which sense the temperature.
Umar Farooq Senior Chemist
NOMAC SIWEP Shuaibah Jeddah 4

5. Fundamental of Heat
 Latent Heat: The heat added or taken into produce a change in
state with out any change in temperature.
 Latent heat of evaporation: The amount of heat which is added
for the evaporation of liquid is called latent heat of evaporation
 Latent heat of vaporization: The amount of heat required to
vaporize 1Lb of water to steam at 14.7psi at 212C* is termed as
latent heat of vaporization.
 Latent heat of fusion: It is the amount of heat required to melt 1g
of ice into water at 0C* or 32 F*.
 Latent heat of condensation: The amount of heat taken to
condense 1 Lb of steam into water at 14.7psi and 212 F*
Umar Farooq Senior Chemist
NOMAC SIWEP Shuaibah Jeddah 5

6. Heat Transfer ( Conduction )
Heat always flows from a warm area to cool area .i.e. from hot body to cold
body This is accomplished in three ways.
 Conduction: In this
method heat energy is
conducted through a
substance or metal or
transferred from one
place to another place or
from molecule to
molecule . The amount of
heat that will pass
through a given material
depends on conductivity
of material.
Umar Farooq Chemist “A” SEC
Shoaiba Jeddah 6

7. Heat Transfer ( Convection )
 Convection: In this method
heat energy is transmitted from
hot to cold body by movement
of conveying subs:
(medium).In side boiler
,furnace the conveying
substance is the gases of
combustion . In this case the
hot body is flue gases the cold
body is boiler tubes, air pre
heater or any things else
having a lower temperature in
the flue gas path.
Umar Farooq Chemist “A” SEC
Shoaiba Jeddah 7

8. Heat Transfer ( Radiation )
 Radiation In this method
heat energy is transfer
from one place to another
place with out the help of
any medium. Heat is
transferred directly by
heater radiation that
require no
intermedium.eg heat of
sun rating to the earth.
Umar Farooq Chemist “A” SEC
Shoaiba Jeddah 8

9. Heat Transfer
 Saturated ( wet ) Steam
Steam containing maximum water vapors that it can steam
is said to be saturated. When it temperature is the same as that of boiling
water at pressure e.g.. At 14.7psi water boiled at 212F* and the saturated
steam temperature is 212 F*.
 Super heated steam ( Dry Steam )
The steam having temperature higher than its
saturation temperature. The addition of heat to saturated steam increase its
temperature or sensible heat. The increase in sensible heat above
saturation temperature is called super heated steam.
If saturated steam at 1500psi and 569.23F* is heated to 950F* with
pressure remaining constant the amount of super heated is 950-
596.23=353.77F*
Un like saturated steam a loss of heat from superheated steam
result is reaction in temperature.
Umar Farooq Chemist “A” SEC
Shoaiba Jeddah 9

10. Steam Water Cycle System
 The Circulation of water
from condenser to boiler
is called water cycle from
boiler to turbine and then
again in condenser is
called steam cycle
collectively it is called
steam water cycle . All
the equipment of this
system are explained
below.
Umar Farooq Chemist “A” SEC
Shoaiba Jeddah 10

11. Condenser Function
Umar Farooq Chemist “A” SEC
Shoaiba Jeddah 11
It is a large hollow
box rows of small tubes
are installed in Cold water
passes through these
tubes , steam condense
outside these tubes and
collected in hot well which
is at the bottom of
condenser.

12. Condenser Function
 While converting steam into water a
vacuum is also created in the condenser
which make the turbine operation more
efficient because pressure of exhaust
steam is reduced by condensation than
reason flow of steam will increase the
cover this pressure and this process help
to move the turbine more fast.
Umar Farooq Chemist “A” SEC
Shoaiba Jeddah 12

13.  Surface type condenser
In this type cooling water is inside the tube while
steam is outside the tubes.
 Contact type Condenser
In this type of condenser condensation takes place
by direct contact i.e. exhausted steam and
cooling water are mixed together.
 Condenser pumps
These pumps takes condensed water from hot well
and give to the main condensate line.
Umar Farooq Chemist “A” SEC
Shoaiba Jeddah 13

14. Steam jet air Ejector
 Since condenser operates under
vacuum , small quantity air comes
from joint of the condenser ,
exhausted steam also contains non
condensable gases which are coming
from turbine sealing drains into
condenser , this air will cause the
condenser to become air bond.
Air in the condenser will
cause a loss of vacuum and decrease
the cooling of exhaust steam . To
eliminate this problem. There is an
instrument which is attached to the
condenser to remove air and ensure
vacuum . This instrument are called
steam jet air ejector.
Umar Farooq Chemist “A” SEC
Shoaiba Jeddah 14

15. Steam jet air Ejector
 Vacuum of condenser may drop due to
following reason.
1) By increasing the temperature of cooling water
2) By decreasing the flow of cooling water .
3) An increasing in level of S.J.A.E.
4) Reducing pressure of ejector operating steam.
5) By increasing level of condenser from it normal stage
6) Leakage of diaphragm .
7) Over loading of condenser.
Umar Farooq Chemist “A” SEC
Shoaiba Jeddah 15

16. Dearator and Feed Tank
 There are two type of dearator
1) Spray Type
2) Tray Type.
The working principle of both dearator are same , but
there is difference of design. The spray type dearator are
only used in marine ship.
In power plant house after last heater condensate
water is taken spray type dearator .which removed
dissolved gases like O2,CO2,N2,NH3 from condensate
water. Umar Farooq Chemist “A” SEC
Shoaiba Jeddah 16

17. Dearator and Feed Tank
 Water temperature ( 145 C* )
Comes downward init a no: of
perforated plates and steam
temperature ( 150 C* ) goes to the
up ward direction. So it contact
with the water , which is in form of
droplets. Steam heated due to
high temperature gases expands
and the solubility decrease. This
mixture is removed from the top of
the dearator which is filled at the
bottom of the Dearator called feed
tank.
Umar Farooq Chemist “A” SEC
Shoaiba Jeddah 17

18. Steam Generator ( Boiler )
 Boiler are built in verity of sizes
shapes and form to fulfill the
conditions of different kinds of
plants.
Generally boilers are
classified into two groups.
Fire tube Boiler
 Fire tube boiler are those in
which hot combustion products
pass through the tube heat is
transferred to water which
surrounding the tubes.
Umar Farooq Chemist “A” SEC
Shoaiba Jeddah 18

19. Advantages of fire tube boilers
1)Low cost
2)Fluctuations of steam demand can be met easily
3)It is compact in size.
Water tube boilers are classified as
1. Horizontal straight tube boilers
(a) Longitudinal drum (b) Cross-drum.
2. Bent tube boilers
(a) Two drum (b) Three drum
(c) Low head three drum (d) Four drum.
3. Cyclone fired boilers
Umar Farooq Chemist “A” SEC
Shoaiba Jeddah 19

20. Advantages of fire tube boilers
According to position of furnace.
(i) Internally fired (ii) Externally fired
 In internally fired boilers the grate combustion chamber
are enclosed within the boiler shell
 whereas in case of extremely fired boilers and furnace
and grate are separated from the boiler shell.
According to the position of principle axis.
(i) Vertical (ii) Horizontal (iii) Inclined.
Umar Farooq Chemist “A” SEC
Shoaiba Jeddah 20

21. Steam Generator ( Boiler )
Water tube boiler
 Water tubes boiler are those in which
products of combustion pass ( through )
around the tubes containing water.
Classification of Boilers
Based on boiler pressure
1) Low pressure boiler under 20kg/cm2
2) Medium pressure boiler 20- 75 kg/cm2
3) High pressure boiler above 75 kg/cm2
Umar Farooq Chemist “A” SEC
Shoaiba Jeddah 21

22. Classification of Water tube boiler
Umar Farooq Chemist “A” SEC
Shoaiba Jeddah 22
 Fuel oil-fired and natural gas-fired water tube package
boilers are subdivided into three classes based on the
geometry of the tubes.
 The “A” design has two small lower drums and a larger
upper drum for steam-water separation.
 The “D” design, which is the most common, the unit
has two drums and a large-volume combustion
chamber. The orientation of the tubes in a “D” boiler
creates either a left- or right-handed configuration.
 The “O” design, the boiler tube configuration exposes
the least amount of tube surface to radiant heat. Rental
units are often “O” boilers because their symmetry is a
benefit in transportation

23. Merits of water tube boilers over
fire tube boilers
 Generation of steam is much quicker due to small ratio
of water
content to steam content. This also helps in reaching
the steaming temperature in short time.
 Its evaporative capacity is considerably larger and the
steam pressure range is also high-200 bar.
 Heating surfaces are more effective as the hot gases
travel at right angles to the direction of water flow.
 The combustion efficiency is higher because complete
combustion of fuel is possible as the combustion space
is much larger.
Umar Farooq Chemist “A” SEC
Shoaiba Jeddah 23

24. Merits of water tube boilers over
fire tube boilers
 The boiler can be easily transported and erected as its
different parts can be separated.
 The thermal stresses in the boiler parts are less as
different parts of the boiler remain at uniform
temperature due to quick circulation of water.
 Damage due to the bursting of water tube is less
serious. Therefore, water tube boilers are sometimes
called safety boilers.
 All parts of the water tube boilers are easily accessible
for cleaning, inspecting and repairing.
 The water tube boiler's furnace area can be easily
altered to meet the fuel requirements.
Umar Farooq Chemist “A” SEC
Shoaiba Jeddah 24

25. Demerits
 It is less suitable for impure and sedimentary water, as
a small deposit of scale may cause the overheating and
bursting of tube. Therefore, use of pure feed water is
essential.
 They require careful attention. The maintenance costs
are higher.
 Failure in feed water supply even for short period is
liable to make the boiler over-heated.
Umar Farooq Chemist “A” SEC
Shoaiba Jeddah 25

26. Comparison between Fire-tube & water-tube boilers
S no. Particulars Fire tube boilers Water tube boilers
1. Mode of firing Internally fired Externally fired
2. Rate of steam
production
lower Higher
3. construction Difficult Simple
4. transportation Difficult Simple
5. Treatment of water Not so necessary More necessary
6. Operating pressure Limited to 16 bar Under high pressure as
100 bar
7. Floor area More floor area Less floor area
8. Shell diameter Large for same power Small same power
9. explosion Less More
10. Risk of bursting lesser More risk

27. Parts of Boiler
Boiler Auxiliaries
Boiler EX- Auxiliaries
Boiler Safety
Boiler Auxiliaries
Steam Drum
 Steam drum is made up of steal and is that part
of boiler , where steam is separated and all the
impurities of the system are collected here and
expelled out by blow down.
Umar Farooq Chemist “A” SEC
Shoaiba Jeddah 27

28. Parts of Boiler
Supper Heater
An equipment or device
in which heat could be added to steam
after its leave the boiler drum is known
as super heater .super heater tubes
are made up of special alloy steel
placed in the flue gas path and the wet
steam is heated there to produce dry
steam called as super heated steam .
It has two advantage over
wet steam.
1) It increase the efficiency.
2) By the use of super heated steam
condensation of steam is the turbine
is minimized to a point where it is
harm less.
Umar Farooq Chemist “A” SEC
Shoaiba Jeddah 28

29. Parts of Boiler
Generation tubes ( Up risers )
These tubes are directly
placed in the path of hot flue
gases. These tubes received
water from drum and contain
mixture of water and steam when
heated by flue gases.
Down Comers
The tubes in which water
flow down ward with respect to up
risers. These tubes not only
protect the furnace wall but also
become an important part of the
furnace heating surface.
Umar Farooq Chemist “A” SEC
Shoaiba Jeddah 29

30. Parts of Boiler
Furnace
The most important
device where actual burning
of the fuel tubes place energy
produced in furnace is used
to heat water and change it in
to steam.
Economizer
The economizer is a heat
exchanger where heat from
flue gases can be used to
heat the feed water
economically.
Umar Farooq Chemist “A” SEC
Shoaiba Jeddah 30

31. Economizer Function
.
Umar Farooq Chemist “A” SEC
Shoaiba Jeddah 31
Flue gases coming out of
the boiler carry lot of
heat. An economizer
extracts a part of this heat
from flue gases and uses
it for heating feed water.
This use of economizer
results in saving fuel
consumption and higher
boiler efficiency

32. Parts of Boiler
Cyclone separator.
It is a device which use
the centrifugal action for
separation of material of
different densities. These are
placed in boiler drum and are
made up of steel.
Burners
These are adjusted in
the wall of furnace.
Fuel starts to burn here.
Umar Farooq Chemist “A” SEC
Shoaiba Jeddah 32

33. Parts of Boiler
Stack Chimney
These portion from
where the flue gases are
expelled out from furnace to
the atmosphere.
Re Heater
Re heaters heat the
steam after it passes through
high pressure turbine. They
are just after super heaters in
the path of flue gases.
In re heaters
temperature of steam rise to
increases the efficiency of
turbine.
Umar Farooq Chemist “A” SEC
Shoaiba Jeddah 33

34. Boiler Ex auxiliaries
Air pre heaters
The air pre heater in steam
generating unit reclaim some heat from flue
gases and adds the heat to the air required for
the combustion of fuel rise of pre heated air will
speed up the combustion al all loads improve
combustion allow load and increases efficiency .
Air pre heater are generally of two type.
1) Tubular air pre heater
2) Rotary air pre heater.
Umar Farooq Chemist “A” SEC
Shoaiba Jeddah 34

35. Air pre heater
 There are three types
of air pre heater:
1. Tubular type
2. Plate type
3. Storage type
 This picture shows that a
tubular type air pre heater.
Umar Farooq Chemist “A” SEC
Shoaiba Jeddah 35

36. Boiler Ex auxiliaries
Induced draft fan
Induced draft fan are used to remove
the flue gases from furnace to chimney
Forced draft fan
It takes the air from atmosphere and after heating
by pre heater suppress air to two places by force.
Air supplied for combustion in of two types.
1) Primary air ( used for burning with gases fuel )
2) Secondary air ( use for adjusting the flame )
Recirculation fan
 Recirculation fan are used to keep the
temperature constant in furnace chamber .
It also used for extra heating to air coming
from atmosphere.
Umar Farooq Chemist “A” SEC
Shoaiba Jeddah 36

37. Boiler Safety Equipment
Inter lock system.
Inter lock system is used in the boiler to prevent
it from ( boiler ) damage .
Boiler is tripped in the following condition
1) When gas air ratio disturbed
2) When level of water decreases
3) On the failure of forced draft fan
4) When turbine trips boiler also trips
Safety valve
It is set up for safety of boiler and adjusted above the
required pressure and when pressure rises from limiting
factor. Then the extra pressure of boiler is maintain with
in the limit. Umar Farooq Chemist “A” SEC
Shoaiba Jeddah 37

38. ESP System
 ESP system have
several vertical chargeable
plates ,these plates charged
with citrine
 Current to remove the ashes
& dusts from the Hot Gases
& delivered the ashes to Silo
Tank & then to Ash Truck.
Umar Farooq Senior Chemist
NOMAC SIWEP Shuaibah Jeddah 38

39. Turbine & it types
 Turbine is a device which converts heat
energy into mechanical energy .
There is number of
blades on the wheels at same axle ( rotor )
and between there are also wheels which
don't move called stationary blades. By
these blades steam gets pressure again
and act upon next blades through nozzles
with high speed and soon.
It is necessary to extract
steam from its out let other wise pressure
will become same at out let and inlet and
turbine is stopped and it may damage any
part . steam is extract from turbine and
used for different purposes.
A large amount of steam
is condensed in condenser to use it again
for turbine rotation.
Umar Farooq Chemist “A” SEC
Shoaiba Jeddah 39

40. Turbine & it types
Turbine is
classified into three types
based on blades of
turbine.
1) Impulse type turbine
2) Reaction type turbine
3) Velocity compound type
turbine
Umar Farooq Chemist “A” SEC
Shoaiba Jeddah 40

41. In a Thermal Power Plant generally 3 turbines are used to increase the efficiency.
 High Pressure Turbine(HPT): The superheated steam is directly fed to this
turbine to rotate it.
 Intermediate Pressure Turbine(IPT): The out put from the HPT is reheated in a
reheated(RH) and used to rotate IPT .
 Low Pressure Turbine(LPT): The Exhausted steam from the IPT is directly fed
to rotate the shaft of LPT.
Turbine
Condenser
HPT IPT LPT
RH
Steam
Super
Heater
Generator
Steam
Shaft
*All the turbines are connected to a single shaft which is connected
to the Generator.
167 Bar
541C˚
40 Bar
541C
5 Bar
246C

42. Generator
It is final and main part
of power plant house where electricity
is produced. An electrical generator or
is a device where mechanical energy
converted into electrical energy .
In generator a magnet
moves with the movement of turbine
shaft . Electrical field is produced in the
winding of stator. The winding will heat
up due to current pressure with may
resist in the flow of current . So it is
necessary to keep it cool. There fore
demineralization water and hydrogen
gas are used for this purpose.
Umar Farooq Chemist “A” SEC
Shoaiba Jeddah 42

43. The Synchronous Generator is used to Generate power by connecting the
shaft of the Turbine to the shaft of the generator which cuts the
magnetic flux producing EMF.
 The Generated Voltage will generally 11KV to 20 KV max.
 The Generated Voltage is stepped up by connecting Step up
transformer and is transmitted and is also used for Auxiliary purposes.
Generator
Bus Duct
Generator Transformer
20KV to 400KV
SYNCHRONOUS
GENERATOR
UAT
20Kv to 6.KV
Unit Auxiliary Transformer: This transformer is used to step down the
produced voltage and use for Auxiliary purpose.

44. Umar Farooq Chemist “A” SEC
Shoaiba Jeddah 44