Internship Report GENCO III TPS Muzaffergarh By Arshad Abbas

MNS UNIVERSITY OF ENGINEERING & TECHNOLOGY MULTAN
DEPARTMENT OF MECHANICAL ENGINEERING
SUBMITTED BY:
Arshad Abbas 2012-BT-MECH-121
Muhammad Umair Aziz 2012-BT-MECH-131
SUBMITTED TO:
Mr. Muhammad Aon Ali Ms. Sania Azam
(Lecturer MNS UET Multan) (Lecturer MNS UET Multan)
Mr. Shahzad Ahmad Mr.Muhammad Umar Khalidoon
(Lecturer MNS UET Multan) HOD Department of Mechanical Engineering
MNS UET Multan
NORTHERN POWER GENERATION COMPANY LIMITED
GENCO III
THERMAL POWER STATION MUZAFFARGARH
INTERNSHIP REPORT
JAN 20-2016 --- MAY 20-2016

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MNS UNIVERSITY OF ENGINEERING & TECHNOLOGY MULTAN
DEPARTMENT OF MECHANICAL ENGINEERING
Certificate
The undersigned certify that they have read and recommended to “MNS UET MULTAN’’ for acceptance,
an internship report entitled ‘’Internship Report on Thermal Power Station Muzaffargarh” in partial
fulfill the requirement for the degree of B.Sc. Mechanical Engineering Technology.
This report is submitted by;
ARSHAD ABBAS (2012-BT-MECH-121)
MUHAMMAD UMAIR AZIZ (2012-BT-MECH-131)
(Mr. Muhammad Aon Ali) (Mr. Shahzad Ahmad)
Lecturer MNS UET Multan Lecturer MNS UET Multan
(Ms. Sania Azam) Mr. Muhammad Umar Khalidoon
Lecturer MNS UET Multan HOD Department of Mechanical Engineering
MNS UET MULTAN
DATE: -06-2016

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ACKNOWLEDGEMENT
First and foremost we would like to express our thanks to Almighty ALLAH because of His love and
strength that He has given to us to finish this (INTERNSHIP) industrial Training as a Trainee Engineer.
We do thank for His blessings to our daily life, good health, healthy mind and good ideas.
Industrial Training is a golden opportunity for learning and self-development. We consider our self very
lucky and honored to have so many wonderful people lead us through in completion of this Training.
Special thanks to Mr. Muhammad Aon Ali who has given us to opportunity for industrial training.
Besides that we wish to express our indebted gratitude and special thanks to our Internship Supervisor "
Eng. Muhammad Mudasir AME Thermal power Station Muzaffargarh" who in spite of being
extraordinarily busy with his duties, took time out to hear, guide and keep us on the correct path and
allowing us to carry out our Industrial Training work at their esteemed organization and extending during
the training.
Internship Supervisor:
Eng. Muhammad Mudassir (AME)
Thermal Power Station Muzaffargarh

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CONTENTS
1. Chapter Introduction ….………………….………………………………………12
1.1. Plant Lay Out …………………………...………………………………………..……….12
1.2. Industrial Background …………………………….………………………………..…….13
1.3. Thermal Power Station Muzaffargarh …………………………………………...…….…13
1.4. The Rankine Cycle ………………………………………………………….….…..…….14
2. Chapter Decanting Section …………………….…….…………………..……….16
2.1. Decanting Area …………………………………………………………………...………16
2.2. Fuel Oil Tank …………………………………………………….……………………….16
2.3. Furnace Oil Flow Cycle …………………………………………………………………..17
2.4. Recirculating Heater ……………………………………………………...………………17
2.5. First Lift Pump ………………………………………...………………………………….18
2.6. Main Heater …………………………………………..…………………………………..18
2.7. Second Lift Pump…………………………………………………………………………19
2.8. Fuel Oil Flow Cycle ……………………………………………………………………...19
3. Chapter Boiler Section ……………………………………………………………20
3.1. Boiler ……………………………………………………………………………………..20
3.2. Types Of Boiler ………………………………………………………….………………20
3.2.1.Fire Tube Boiler ……………………………………………………………………………..20
3.2.2.Water Tube Boiler ……………………………………………………………….………….20
3.3. Boiler Parameter ………………………………………………………..………………..20
3.4. Types Of Boiler According To Steam Pressure …………………………………...……..21
3.4.1.Sub Critical Pressure Boiler …………………………………………..………….…………21
3.4.2.Super Critical Pressure Boiler …………………………………….………...………………21
3.5. Main Parts Of Boiler…………………………………………..…………………………. 21
3.6. Draft ………………………………………………………….……………..…………… 21
3.6.1.Natural Draft ………………………………………………………….………….………….21
3.6.2.Mechanical Draft …………………………………………………….……………………..21
3.6.2.1. Forced Draft ……………………………………………….…………….………22
3.6.2.2. Induced Draft …………………………………………….……………..……….22
3.6.2.3. Balanced Draft ………………………………………………………..…………22
3.7. Force Draft Fan ……………………………………………………………….……….….22
3.8. Induced Draft Fan …………………………………………………………………..…….23
3.9. Calorifier ………………………………………………………………………………….24
3.10. Regenerative Air Heater ………………………………………… …………….………..24
3.11. Combustion Air Cycle ………………………………………………….………...………25
3.12. Gas Recirculation Fan ………………………………………………………………..….25

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3.13. Duct ………………………………………………………………………………….…..26
3.14. Damper …………………………………………………………………………………...26
3.15. Furnace …………………………………………………………………………………..26
3.16. Burner …………………………………………………………………...………………..26
3.16.1. Specification Of Burner ………………………………………………………………….27
3.17. Steam Atomization Of Fuel ………………………………………………………………27
3.18. Purging Steam ………………………………………………………………………….…28
3.19. Boiler Drum …………………………………………………………………………...…28
3.20. Down Comers Tubes ……………………………………………………………………..29
3.21. Up Riser Tube…………………………….……………………………….........................29
3.22. Super Heaters ………………………………………………………………………….….29
3.22.1. Radiation Super Heater …………………………………………………………………...30
3.22.2. Convection Super Heater ………………………………………………………….……...30
3.23. Attemperator ……………………………….……………………………………..………31
3.24. Economizer ……………………………………………………………………....………31
3.25. Boiler Mountings ……………………………………………………………..….……….32
3.26. Boiler Blow Down …………………………………………………………….………….32
3.27. Soot Blower …………………………………………………………………..……….….32
3.28. Chimney …………………………………………………………………………..............33
3.29. Preventing Cold End Corrosion In Boiler ………………………………………….……33
3.30. Steps To Reduce Cold End Corrosion In Boiler ………………………………………….34
3.31. Losses In Boiler…………………………………………………………………………...34
3.32. Boiler Efficiency …………………………………………………………………….……34
3.32.1. Indirect Method ……………………………………………………..…………….……..34
3.32.2. Direct Method ……………………………………………………………………..……..34
3.33. Valve ………………………………………………………………….………….….…..35
3.33.1. Types Of Valve …………………………………………………………..………………35
3.33.1.1. Gate Valve ………………………………………………….……………………35
3.33.1.2. Globe Valve …………………………………………………………...…………36
3.33.1.3. Pressure Relief Valve …….……………………………………………..……….36
3.33.1.4. Pressure Safety Valve ………………………………………………………..…..37
4. Chapter Steam Turbine ……………………..…………………………..……..…38
4.1. Steam Turbine …………………………………………………………………………….38
4.2. Impulse Turbine ……………………………………………………………….………….38
4.2.1. Velocity Compound Of Impulse Turbine ………………………………………………..39
4.2.2. Pressure Compound Of Impulse Turbine …………………………………………...……40
4.3. Reaction Turbine …………………………………………………………………………41
4.3.1. Pressure Compound Of Reaction Turbine ………………………………………….....….41
4.4. Turbine Description ……………………………………………………………………....42

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4.4.1. Turbine Model ……………………………………………….…………………………...42
4.4.2. H.P Turbine ………………………………………………….………………………..…42
4.4.3. I.P Turbine ………………………………………………………..……………….……..42
4.4.4. L.P Turbine ……………………………………………………………………….………42
4.5. Reheater ……………………………………………………….………………………….42
4.5.1. Reheat Cycle ……………………………………………..……………………………….42
4.6. Live Steam Cycle …………………………………………………………………………43
4.7. Parts Of Turbine ……………………………………………………………………….…44
4.7.1. Turbine Casing ……………………………………………………...…………….……..44
4.7.2. Turbine Rotor …………………………………………………………….…………..….44
4.7.3. Journal Bearing ……………………………………………………….………………….44
4.7.4. Thrust Bearing …………………………………………………………..………………..44
4.8. Axil Shift ………………………………………………………………………..……….45
4.9. Turning Gear ……………………………………………………………………..…….…45
4.10. Gland Sealing System ……………………………………………………………….……45
4.11. Blade Material ……………………………………………………………………………46
4.12. Condenser …………………………………………………………………….…………..46
4.13. Condensate Pump ……………………………………………...…………………………47
4.14. Steam Air Ejector …………………………………………………….…………………..47
4.15. Gland Steam Condenser ……………………………………………...…………………..47
4.16. L.P Heaters …………………………………………………………...……….………….47
4.17. Condensate Cycle ………………………………………………………….…………….48
4.18. Dearator …………………………………………………………………………………..49
4.19. Boiler Feed Water Tank ………………………………………………………..…………49
4.20. Feed Water Pump …………………………………………………………..…………….49
4.20.1. Parts Of Feed Water Pump ……………………………………………………………….50
4.20.1.1. Impeller Diffuser ……………………………………………………..………….50
4.20.1.2. Hydraulic Coupling …………………………………………………………...…51
4.20.1.3. Balancing Disk ………………………………………………………………….52
4.20.1.4. Mechanical Seal ………………………………………………………...………..52
4.21. H.P Heater ………………………………………………………………………………..53
4.22. Feed Water Cycle …………………………………………………………………….…..53
5. Chapter Cooling Tower Section ……………………………………….…………54
5.1. Cooling Tower ………………………………………………...………………………….54
5.2. Working Of Cooling Tower ………………………………………..…………………….54
5.3. Types Of Cooling Tower …………………………………………………………………55
5.3.1. Cross Flow Cooling Tower ……………………………….………………………...…….55
5.3.2. Counter Flow Cooling Tower ………………………………………………...…………..55
5.3.3. Forced Draft Cooling Tower ………….………………………………………………….56

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5.3.4. Induced Draft Cooling Tower ………………………………………………..…………...56
5.3.5. Natural Draft Cooling Tower …………………………………………..…………..……..57
5.4. Cooling Tower Fill Type ……………………………………………………...………….57
5.4.1. Fill ………………………………………………………………………………..……….57
5.4.2. Film Fill …………………………………………………………………………………..57
5.4.3. Splash Fill …………………………………………………………………...……………58
5.5. Circulating Water Pump ………………………………………………………….………58
5.5.1. Circulating Water Pump Specifications...…………………… ……………….…………..58
6. Chapter Chemical Water Treatment and Plant Heat Rate …………………….60
6.1. Chemical Water Treatment ………………………………………………….……………60
6.1.1. External Treatment ……………………………………………………………………….60
6.1.2. Internal Treatment ………………………………………………………………………..60
6.2. Water Purification System ………………………………………………………………..60
6.2.1. Mechanical Filters …………………………….…………………………...……………..60
6.2.2. Cation Filter 1 …………………………………..………………………...………………60
6.2.3. De Gassifier ……………………………………..………………………….…………….61
6.2.4. Anion Filter ………………………………………………………………….……………61
6.2.5. Cation Filter 2 ………………………………………………………………...…………..61
6.2.6. Mix Bed Filter ………………………………………………..…………..………………61
6.2.7. Demineralize Water Tank ………………………………………………..………………61
6.3. What Is Heat Rate? ……………………………………………………………………….62
6.4. Plant Heat Rate …………………………………………………………………………...62
6.5. Why Is Heat Rate Important …………………………………………………………..….62
7. Chapter Generator And Transformer …………………………………………….……..64
7.1. Generator …………………………………………………………………………………64
7.1.1. Working Principle Of Generator ……………………………………………...………….64
7.1.2. Generator Parameter ………………………………………………………..…………….65
7.1.3. Cooling System Of Generator ……………….………………………………………..….65
7.1.3.1. Stator Cooling ……………………………………………………………………65
7.1.3.2. Rotor Cooling ……………………………………………………………………66
7.2. Transformer ………………………………………………………………………..……..66
7.2.1. Types Of Transformer ……………………………………………………………………67
7.2.1.1. Step Up Transformer …………………………………………………….………67
7.2.1.2. Step Down Transformer …………………………………………………………67
7.2.1.3. Potential Transformer ………………………………………………...………….68
7.2.1.4. Current Transformer …………………………………………………..…………68
7.2.1.5. Auxiliary Transformer ………………………………………………..………….68
8. Chapter Switch Yard and Equipment Used In Switch Yard ………….….……………70
8.1. Switch Yard ………………………………………………………………………………70

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8.2. Switch Gear ………………………………………………………………………………70
8.3. Bay ……………………………………………………………………………………….70
8.4. Equipment Used In Switch Yard …………………………………………...…………….70
8.4.1. Bus Bar …………………………………………………………………..……………….70
8.4.1.1. Types Of Bus Bar ……………………………………………….……………….70
8.4.2. Circuit Breaker ……………………………………………………………..…………….70
8.4.3. Isolator ………………………………………………………………………...………….71
9. Chapter Air Compressor And Types Of Air Compressor ……………….……..72
9.1. Air Compressor …………………………………………………………………...………72
9.2. Types Of Air Compressor ………………………………………..……………………….72
9.2.1. Rotary Air Compressor …………………………………………….……………………..72
9.2.2. Reciprocating Air Compressor …………………………………..……………………….72

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LIST OF FIGURES
1 Chapter Introduction ……………………………………………..………12
Fig.1.1 Energy Conservation …………………….………………...…………………………….13
Fig.1.2 The Rankine Cycle ……………………………………………………………...………14
2 Chapter Decanting Section ……………………………………...………..16
Fig 2.1 Decanting Area ……………………………………………...…………………………….16
Fig 2.2 Fuel Flow Cycle …………………………………………………………………………..17
Fig. 2.3 Fuel Heating Diagram ………………………………………………………………...….17
Fig 2.4 First Lift Pump ……………………………………………………………………………18
Fig 2.5 Fuel Flow Cycle …………………………………………………………….…………….19
3 Chapter Boiler Section ……………………………………………………20
Fig 3.1 Draft System ………………………………………………………………………………21
Fig 3.2 Force Draft Fan ……………………………………………………………..…………….22
Fig 3.3 Induced Draft Fans ……………………………………………….……………………….23
Fig 3.4 Calorifier ………………………………………………………………………….………24
Fig 3.5 (a) RAH Element (b) Regenerative Air Heater ……………………………………..…….24
Fig. 3.6 Combustion Air Cycle ……………………………………………………………...…….25
Fig 3.7 (A) Air Ducts (B) GRC Fan …………………………………….……………..………….25
Fig.3.8 (a) Front-Wall-Fired Furnace (b) Opposed-Wall-Fired Furnace (c) Corner-Fired
Furnace……………………………………………………………………………………….……26
Fig 3.9 Burner ………………………………………………….………………………………….27
Fig. 3.10 Steam Atomization ……………………………………………………………...………28
Fig. 3.11 Oil Gun …………………………………………………………………….……………28
Fig 3.12 Boiler Drum ……………………………………………………………………………..29
Fig. 3.13 Superheaters ………………………………………………………………….…………30
Fig. 3.14 Desuperheater (Attemperator) …………………………………………….…………….31
Fig. 3.15 Economizer ………………………………………………………….………………….31
Fig. 3.16 Soot Blower ………………………………………………………..……………………32
Fig. 3.17 Chimney ………………………………………………………………...………………33
Fig.3.18 (a) Gate Valve (B) Parts of Gate Valve …………………………………………………35
Fig.3.18 (c) Gate Valve drawing symbol …………………………………………………………36
Fig.3.19 (a) Globe Valve (B) Parts of Globe Valve (c) Drawing Symbol of Globe Valve …….…36
Fig.3.20 Pressure Relief Valve …………………………………………………………...……….37
Fig.3.21 Pressure Safety Valve ………………………………………………………...…………37
4 Chapter Turbine Section …………………………………………..……...38
Fig. 4.1 Multi Stage Steam Turbine …………………………….……………………...…………38
Fig. 4.2 Schematic Diagram of Velocity Compounded Impulse Turbine …………………...……39

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Fig 4.3 Schematic Diagram of Pressure compounded Impulse Turbine ………….………………40
Fig. 4.4 Schematic Diagram of Pressure Compounded Reaction Turbine ………………..………41
Fig.4.5 Reheat Cycle …………………………………………………………………….………..42
Fig.4.6 Live Steam Cycle ………………………………………………………………..………..43
Fig.4.7 Thrust Bearing …………………………………………………………………...………..45
Fig.4.8 Surface Condenser ……………………………………………………………….……….46
Fig.4.9 Condensate Cycle …………………………………………………………………………48
Fig.4.10 Dearator ………………………………………….………………………………………49
Fig.4.11 Boiler Feed Water Pump Impeller Diffuser ……………………………………..………50
Fig.4.12 (a) Diffuser (b) Impeller …………………………………………………………………51
Fig.4.13 Hydraulic Coupling ……………………………………………………………….……..51
Fig.4.14 Mechanical Seal …………………………………………………………………………52
Fig.4.15 Feed Water Cycle ………………………………………………………………….…….53
5 Chapter Cooling Tower ………………………………………………...…54
Fig.5.1 Cooling Tower ……………………………………………………………………………54
Fig.5.2 Cross Flow Cooling Tower ……………………………………………………………….55
Fig.5.3 Counter Flow Cooling Tower …………………………………………………...………..55
Fig.5.3 Force Draft Cooling Tower ……………………………………………………….………56
Fig.5.4 Induce Draft Cooling Tower ……………………………………………………...……..56
Fig.5.5 Natural Draft Cooling Tower ……………………………………………………...…….57
Fig.5.6 Film Fill Design …………………………………………………………………………..57
Fig.5.7 Splash Fill Design ……………………………………………………………..…………58
Fig.5.8 Cooling Water Pipes ………………………………………………………….………….59
6 Chapter Chemical Water Treatment and Plant Heat Rate …………….60
Fig.6.1 Water Treatment Plant Diagram ………………………………………………………….61
7 Chapter Generator and Transformer ……………………………………64
Fig.7.1 Generator Working Principle ……………………………………………………………..64
Fig. 7.2 Transformer ………………………………………………………………………..……..67
Fig. 7.3 Step Up Transformer ……………………………………………………………………..67
Fig. 7.4 Step Down Transformer ………………………………………………………….………67
Fig. 7.5 Potential Transformer ………………………………………………………………….…68
Fig. 7.6 Current Transformer …………………………………………………………………...…68
Fig. 7.7 Auxiliary Transformer ……………………………………………………………..…….69
8 Chapter Switch Yard and Equipment Used In Switch Yard ………………..…70
Fig. 8.1 Circuit Breaker ……………………………………………………………..…………….71
Fig. 8.2 Isolator ………………………………………………………………………..…………..79

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List of Table
Table 1.1 Plant Installed Capacity………………………………………………………………...14
Table 2.1 First Lift Pump motor specifications ………………..………………………………………………………..18
Table 2.2 Second Lift Pump motor specifications ……………………………………………..…19
Table 3.1 Boiler Perimeters ………………………………………………………………………20
Table 3.2 FDF Motor Specifications ……………………………………………………………...23
Table 3.3 IDF Motor Specifications ……………………………………………………………...23
Table 3.4 GRC Fan Motor Specifications ……………………………………………….………..26
Table 3.5 Burner Specifications …………………………………………………………………..27
Table 4.1 Parts of Turbine ………………………………………………………………………...44
Table 4.2 L.P Heater Bleedings …………………………………………………………………..47
Table 4.3 H.P Heater Bleedings …………………………………………………………………..53
Table 5.1 C.W.Pump Motor Specifications ………….…………………………………………...58
Table 5.1 C.W.Pump Motor Specifications ………………………………………………………65
Table 9.1 Compressor Pressure and Dia.of Each Stage ………………………………………….72
Table 1 Plant Fuel Consumption ………………………………………………………………….73
Table 2 Fuel Cost /Kwh …………………………………………………………………………..74
Table 3 Generation Cost R.s/kWh ………………………………………………………………..75

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List of Graph
1. Thermal Efficiency Graph of Year 2009 To 2015 ……………………………………………73
2. Graph of Fuel Cost Per Kwh: …………………………………………………………………74
3. Graph of Generation Cost/kWh ………………………………………………………………75
4. Energy Generation Source Vies Graph: ………………………………………………………76

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CHAPTER 01
INTRODUCTION
1.1 Plant Lay Out

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1.2 Industrial Background:
A thermal power station is a power plant in which the prime mover is steam driven. Water is heated, turns
into steam and spins a steam turbine which either drives an electrical generator or does some other works.
After it passes through the turbine, the steam is condensed in a condenser and recycled to where it was
heated, this is known as a Rankine cycle. The greatest variation in the design of thermal power stations is
due to the different fuel sources. Some prefer to use the term energy center because such facilities convert
forms of heat energy into electrical energy.
Fig. 1.1 Energy Conservation
The furnace is surrounded by tubes filled with water. The immense heat from the burning turns the water
in the tubes into steam. The steam is then transferred under pressure at high speed through large pipes to a
turbine where it pushes the turbine blades causing them to spin. The steam is condensed back to water
using cooling water; it is then pumped back into the water tubes surrounding the furnace to continue the
process.
As per Government of Pakistan policy all thermal power generation has been restructured and four
corporatized companies namely Jamshoro Power Generation Company Limited (GENCO-1) headquarter at
Jamshoro near Hyderabad Sindh, Central Power Generation Company Limited (GENCO-2) head quarter at
Guddu district Jacobabad Sindh and Northern Power Generation Company Limited (GENCO-3)
headquarter at Muzaffargarh and Lakhra Power Generation Company Limited (GENCO-IV) at Khanote
(Sindh) have been formed and registered. Functioning of GENCOs has commenced.
1.3 Thermal Power Station Muzaffargarh
(Northern Power Generation Company Limited (GENCO-III))
This thermal power station is situated in Multan division’s district Muzaffargarh. In 1985 Gulam Ishaq
Khan made an agreement with Russia for the establishment of the power station. Initially this project was
documented for Multan. But due to certain reasons like availability of land, cost etc. This project shifted to
Muzaffargarh. About 2500 people are working in this organization including both technical &non-
technical.
TPS Muzaffargarh is classified in two phases.
Phase: 1
Phase: 2
Phase # 1 (Units 1, 2, 3 & 4):

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This phase consist of four steam units capable of generating 210MW (1, 2, 3 each unit) and unit 4 (320
MW) electricity.
Phase # 2 (Units 5 & 6):
It consists of two units of 200MW each. Phase 2 based on China technology. Total plant installed capacity
is 1350 MW.
Unit# Installed Capacity
Working Capacity
(Avg)
Constructed By: Construction Date
1 210 MW 175 MW Russian Sep.1993
2 210 MW 170 MW Russian Mar. 1994
3 210 MW 170 MW Russian Feb. 1995
4 320 MW 280 MW China Dec. 1996
5 200 MW 165 MW China Dec.1995
6 200 MW 165 MW China Dec.1995
Total 1350 MW 1125 MW
Table 1.1 Plant Installed Capacity
1.4 The Rankine Cycle:
The Rankine cycle is a model that is used to predict the performance of steam turbine systems.
In the Rankine Cycle; water changes form liquid, to superheated steam and saturated mixture it is also
called the Vapor Power Cycle.
Fig. 1.2 Rankine cycle
There are four processes in the Rankine cycle:
 Process 1-2: The working fluid is pumped from low to high pressure. As the fluid is a liquid at this
stage, the pump requires little input energy.

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 Process 2-3: The high pressure liquid enters a boiler where it is heated at constant pressure by an
external heat source to become a dry saturated vapour.
 Process 3-4: The dry saturated vapour expands through a turbine, generating power. This decreases
the temperature and pressure of the vapour, and some condensation may occur.
 Process 4-1: The wet vapour then enters a condenser where it is condensed at a constant pressure to
become a saturated liquid.

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CHAPTER 2
DECANTING SECTION
2.1 Decanting Area:
The furnace oil that is used as a fuel in the burners of the boiler furnace to produce the steam is transported
to the TPS through two ways:
(1)Oil Tankers
(2) Train
For unloading of the fuel from oil tankers and train there is separate unloading or de-canting station for
each. The unload fuel oil is initially stored in the underground reservoir; from there it is filled in the main
storage tanks. Two pumps are used to fill the main storage tanks from the oil tankers decanting area.
Properties Of Fuel (Furnace Oil) :
Calorific value: 10111 kcal/kg
Flash point: 60 ⁰ c
Viscosity: 120 CST (winter) 180 CST (summer)
Specific Gravity: 0.98 at 15 ⁰c
Moisture Content: 0.5 %
Fig 2.1 Decanting Area
2.2 Fuel Oil Tanks:
From the decanting area the furnace oil is filled in the storage tanks. From there it is supplied to the
burners of the boiler furnace after proper heating. Usually one storage tank is called service tank, from
there furnace oil is supplied to the units. The furnace oil is filled in the main tank first and then filled in the
service tank through recirculation pumps (RCP). The oil in the tanks is kept heated at the temperature 75-
80°C. There are total 06 storage tanks for furnace oil each having a volume of 20,000 m3
hence each can
store 20000 tons. There are two diesel oil storage tanks each having capacity of 1000 tons.
Secondary Fuel (Natural Gas)
C.V : 8425 Kcal/Kg
Starting Fuel (Diesel)
C.V : 9990kcal/Kg

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2.3 Furnace Oil Flow Cycle:
Fig 2.2 Fuel Flow Cycle
2.4 Recirculating Heaters:
The steam recirculating heaters heat the furnace oil through the steam which comes from the boiler. The
steam follows through the pipes which heats the oil outside the tube. The temperature of furnace oil rises
up to 750
c to 800
c. The pressure and temperature of the steam is t 2500
c and p= 13 kg/cm2
Fig. 2.3 Fuel Heating Diagram

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2.5 First Lift Pump:
First lift pump takes the furnace oil from the service tank and supplied to the main heaters. There are total
04 first lift pumps which are operated according to unit load conditions. The specification of first lift pump
motor is as follows;
3 phase 50Hz induction motor.
Pump motor specifications:
Connection Star
Power 55 KW
Efficiency 90%
Voltage 230 To 400 V
Speed 2950 RPM
Capacity 120 M3
/h
Table 2.1 Pump motor specifications
Fig 2.4 First Lift Pump
2.6 Main Heaters:
There are 04 main heaters each is connected to the respective first lift pump. The main heaters heat the
furnace oil through the steam which comes from the boiler. Steam is used to heat the oil in recirculation
heaters. The steam follows through the pipes which heats the oil outside the tube. The temperature and
pressure of the steam in the main heater is;
Temperature 250 0
C
Pressure 13 Kg/Cm2

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2.7 Second Lift Pump:
Second lift pumps take the furnace oil from the main heater and supply to boiler of the units. There are 04
second lift pumps which are operated according to the unit load conditions. The temperature of oil that is
supplied to the boiler is 1050
C- 120°C. The specification of second lift pump motor is as;
3 phase 50Hz induction motor:
Table 2.2 Pump motor specifications
2.8 Fuel Flow Cycle:
Fig 2.6 Fuel Flow Cycle
Connection Star
Capacity 120 M3/h
Power 250 KW
Current 252 A
Speed 2950 RPM

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CHAPTER 3
BOILER SECTION
3.1 Boiler:
Determining plant output and efficiency, boilers are core elements in thermal power generation systems.
The boiler is the main part of any thermal power plant. It converts the fuel energy into steam energy. The
fuel may be furnace oil, diesel oil, natural gas or coal. The boiler may be fire from the multiple fuels.
Boiler is a close vessel. This is full with water and use to make steam.
3.2 Types of boiler:
1. Fire Tube Boiler
2. Water Tube Boiler
3.2.1 Fire tube boiler:
In fire tube boiler, the fuel is burnt inside a furnace. The hot gases produced in the furnace then passes
through the fire tubes. The fire tubes are immersed in water inside the main vessel of the boiler. As the hot
gases are passed through these tubes, the heat energy of the gasses is transferred to the water surrounds
them. As a result steam is generated in the water and naturally comes up and is stored upon the water in the
same vessel of fire tube boiler. This steam is then taken out from the steam outlet for utilizing for required
purpose. The water is fed into the boiler through the feed water inlet. General maximum capacity of this
type of boiler is 17.5 kg/cm2
and with a capacity of 9 Metric Ton of steam per hour.
3.2.2 Water tube boiler:
A water tube boiler is such kind of boiler where the water is heated inside tubes and the hot gasses
surround them. Water tube boilers are also capable of high efficiencies and can generate saturated or
superheated steam. The ability of water tube boilers to generate superheated steam makes these boilers
particularly attractive in applications that require dry, high-pressure, high-energy steam, including steam
turbine power generation. High pressure 140 kg/cm2
can be obtained smoothly.
3.3 Boiler Parameters:
Boiler Manufacturer Russia
Boiler Capacity 670 TPH
Rated Working Pressure 130 kg/cm2
Type of Boiler Water tube Wilcox & Babcock Type Boiler
Fuel Fired Furnace Oil, Diesel and Natural Gas
Rated Working Temperature 545
Boiler efficiency (Burn oil) 90.26%
Boiler efficiency (Burn gas) 85%
Table 3.1 Boiler Perimeters

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3.4 Types of Boiler According To Steam Pressure:
3.4.1 Sub Critical Boiler
 Boiler operating below the critical pressure 224.6 Kg/Cm2
 These are recirculation type or once through
 Steam drum is required to separate water and steam
3.4.2 Super Critical Boiler
 Boiler operating above the critical Pressure 224.6 Kg/cm2
 These are only once through
 Drum is not required
3.5 Main Parts of Boiler:
Boiler of Genco-III is constructed from the following components,
 Furnace
 Boiler Drum
 Super Heaters
 Steam Reheater
 Economizer
 Steam Air Heaters
3.6 Draft:
The difference between atmospheric pressure and the pressure existing in the furnace or flue gas passage
of a boiler is termed as draft
Fig 3.1 Draft System
3.6.1 Natural Draft:
The temperature difference between the outside air and the inside air creates a "natural draft".
The direction of the air flow depends on the temperature of the outside and inside air. If the inside air
temperature is higher than the outside air temperature, the inside air density is less than the outside air
 R.A.H (Regenerative Air Heater)
 G.R.C Fan (Gas Recirculation Fan)
 I.D & F.D Fan
 Attemperator
 Soot Blower
 Chimney

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density, and the inside air will flow up and out of the upper parts of the building. The colder outside air
will flow in to the lower parts of the building.
If the outside air temperature is higher than the inside air temperature - the inside air is more dense than the
outside air - and the air flows down inside in the building. Warmer outside air flows in to the upper parts of
the building.
3.6.2 Mechanical Draft:
The movement of air or flue gases by means of a fan or other mechanical device is called mechanical draft.
Types of mechanical draft are following.
3.6.2.1 Forced Draft:
When air or flue gases are maintained above atmospheric pressure. Normally it is done with the help of a
forced draft fan.
3.6.2.1 Induced Draft:
When air or flue gases flow under the effect of a gradually decreasing pressure below atmospheric
pressure. In this case, the system is said to operate under induced draft.
3.6.2.3 Balanced Draft:
When the static pressure is equal to the atmospheric pressure, the system is referred to as balanced draft. In
GENCO III balanced draft system is used by using forced draft fan and induced draft fan.
3.7 Force Draft Fan (FDF):
The force draft fan sucks the air from atmosphere which is used in the furnace for burning. The air from
the atmosphere is passed through the filter to remove the dust and other particles from the air. Force draft
fan also suck the air from the turbine hall because the temperature in turbine hall is higher than
atmosphere.
Fig 3.2 Force Draft Fan

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The motor of FDF has following specification:
Rated Voltage 6.6 KV
Connection Of Stator /Rotor Y
No. Of Phases 3
Rated Frequency 50 Hz
Rated Speed 747 RPM
Out Put 1000KW
Power Factor .85
Table 3.2 FDF Motor Specifications
3.8 Induced Draft Fan (IDF):
ID fan sucks the flue gases from the boiler and exhaust through chimney.
Fig 3.3 Induced Draft Fan
The motor of ID fan has following specifications:
Rated Current 20 A
Connection Of Stator/Rotor Y
No. Of Phases 3
Rated Frequency 50 Hz
Rated Speed 991 RPM
Out Put 2000KW
Weight 15970KG
Table 3.3 IDF Motor Specifications

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3.9 Calorifier:
An apparatus for heating (air, water) by circulating it past usually steam-filled heating coils.it is paced
between forced draft fan and regenerative air pre heater. The temperature of air after passing through
calorifier is up to 70 0
C.
Fig 3.4 Calorifier
3.10 Regenerative Air Heater:
Regenerative air heater is used to pre heat air which is used in boiler. It consists of elements which rotate
at 3, 4 rpm. These rotating elements take heat from flow gases and release air which comes from forced
draft fan. The inlet temperature of flue gases is 330 0
c and outlet temperature is 160 0
c. Air enter in to the
regenerative air heater at 70 0
c and leave at 260 0
c.
(a) (b)
Fig 3.5 (a) RAH Element (b) Regenerative Air Heater

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3.11 Combustion Air Cycle:
Fig. 3.6 Combustion Air Cycle
3.12 Gas Recirculation Fan:
G.R.C Fan is installed between the Economizer and Air preheater. It takes the hot flue gases and sent in to
furnace from the opposite side of the burner. It also opposes the flame to touch the furnace wall and also
help to flame rise in upward direction.
(a) (b)
Fig 3.7 (A) Air Ducts (B) GRC Fan

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The motor of GRC fan has following specifications;
Connection Of Stator/Rotor Y
No. Of Phases 3
Rated Speed 1491 RPM
Rated Power 315KW
Rated Frequency 50HZ
Table 3.4 GRC Fan Motor Specifications
3.13 Duct:
Ducts are made of galvanized steel and are often insulated. Ducts are used to exchange hot & cold fluids
mainly gases. Flow of air or gases is controlled by dampers.
3.14 Damper:
A damper is a plate that stops or regulates the flow of air inside a duct, chimney.
3.15 Furnace:
An enclosed structure in which material can be heated at very high temperature. Such as metal will melt or
burn. Furnace temperature varies according to combustion and also No-of Burners. Up riser tubes are
inside the furnace and down comers tubes are outside of the furnace. Temperature in the furnace is 15000
C. in GENCO III gate type and tower type furnaces are used.
(a) (b) (c)
Fig.3.8 (a) Front-Wall-Fired Furnace (b) Opposed-Wall-Fired Furnace (c) Corner-Fired Furnace
 Front Fire (Gate Type ) (Unit 1,2,3)
 Corner Fire (Tower Type) (Unit 4,5,6)

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3.16 Burner:
A device, as in a furnace, stove, or gas lamp, that is lighted to produce a flame.
Fig 3.9 Burner
In GENCO-III TPS there’s are two types of Burners
1. Stationery Burners (Unit 1,2,3) (Fixed )
2. Tilting Burners (Unit 4,5,6) [can be tilted +300
to -300
]
3.16.1 Specification of Burner (Stationary):
Manufacture Russians
Type Of Burner Stationery Type
Oil Capacity 4.2 T/H
Oil Pressure In Burner 40 Kg/Cm
2
No. Of Burners In Furnace 12
Type Of Firing
Front Fire Furnace
Table 3.5 Burner Specifications
3.17 Steam Atomization of Fuel:
The burner lance consists of two concentric tubes, a one-piece nozzle and a sealing nut. The media
supplies are arranged so that the steam is supplied down the centre tube and the fuel oil through the outer
tube. Consequently, the steam space is completely isolated from the oil space.
The steam atomizer consists of an atomizer body that has a number of discharge nozzles arranged on a
pitch circle in such a way that each oil bore meets a corresponding steam bore in a point of intersection.
Oil and steam mix internally forming an emulsion of oil and steam at high pressure. The expansion of this
mixture as it issues from the final orifice produces a spray of finely atomized oil. Oil burners with internal
mix steam atomizing are tolerant to viscosity changes. In addition to this advantage, the steam atomized oil
burners have better turn down; do not require high fuel oil pump pressures.

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Fig. 3.10 Steam Atomization
Fig. 3.11 Oil Gun
3.18 Purging Steam:
Purging steam is used for the cleaning of oil gun. When high steam at high temperature and pressure pass
through the oil gun its remove the scaling this is formed in gun.
3.19 Boiler Drum:
Boiler drum is in cylindrical shape. Half drum is full with demineralized water. Demi water is filled in
drum with 25 ton/h. Water temperature in the drum is 2810
c.
Boiler drum of GENCO-III TPS consists of the following components.
1. Steam outlet Pipelines
2. Down Comer Tubes
3. Riser Header
4. Water Level Gauge
5. Perforated Sheets
6. Man Hole
7. Surging Plates
8. Heating & Cooling Lines
9. Chemical Dozing Line
10. C.B.D (continuous blow down)
11. Pressure Gauges
12. Feed Water Inlet Connections

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Fig 3.12 Boiler Drum
3.20 Down comer tubes:
Water flows downward to the header from the boiler drum. (Natural Circulation) .Total 6 numbers of
down comer tubes.
3.21 Up Riser Tubes:
It takes the water from the header to the boiler drum.(Natural circulation process).
3.22 Super Heaters:
Steam from boiler drum is entre into the super heater for production of superheated steam to run the
turbine. In GENCO-III TPS following four types of super heaters are used,
1. Ceiling Superheater
2. Radiation Super Heater
3. Platen Super Heater
4. Convection Super Heater

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3.22.1 Radiation Superheater:
Radiation based superheater are used to gain higher steam temperatures and the heat is mainly transferred
by radiation. These super heaters have to be placed within reach of the flame radiation. Thus radiant super
heaters are usually integrated as tubes in the boiler walls or built as panels hanging from the boiler roof.
The radiation superheater is located in the top of the furnace, where the main means of heat transfer is
radiation.
3.22.2 Convection Superheater:
Convection superheaters are the most common superheaters in steam boilers. Convection based
superheaters are used with relatively low steam temperature, and the heat from the flue gases is mainly
transferred by convection. They are placed after the furnace protected from the corrosive radiation of the
flames. This type of superheater can also be protected from radiation by a couple of rows of evaporator
tubes. Convection based superheaters can hang from the boiler roof or they can be placed in the second
pass of the boiler.
Fig. 3.13 Superheaters

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3.23 Attemperator:
Temperature control is usually achieved by admitting a fine spray of water into the steam line is called
an attemperator or desuperheater
Fig. 3.14 desuperheater (Attemperator)
3.24 Economizer:
Economizer is a heat exchanger which is used to preheat the feed water by flue gases. After the feed water
pump, the water has the required pressure and temperature to enter the boiler. The pressurized water is
introduced into the boiler through the economizers. The economizers are heat exchangers, usually in the
form of tube packages. The purpose of economizers is to cool down the flue gases leaving the superheater
zone, thus increasing the boiler efficiency.
Fig. 3.15 Economizer

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3.25 Boiler Mountings:
Boiler Mounting are basically used for safe operation of Boiler.
Description of Boiler Mountings
 Safety Valve : The Function of a safety valve is to blow off steam when the pressure in the boiler
exceeds the working pressure.
 Feed Check Valve : A feed check valve is used to control the supply of feed water to boiler &
also to act as a non-return valve.
 Pressure Gauge : Pressure gauge indicates the pressure of steam in a boiler.
 Blow Down Valve : Blow down Valves are designed for continuous use to control the
concentration of dissolved solids in boiler water.
 Main Stop Valve : Function of a steam stop valve is to stop or allow the flow of steam from the
boiler to Main Steam line.
3.26 Boiler Blow Down:
Dissolved solids and particles in the make-up water will remain in the boiler when steam is generated.
During operation the total dissolved solids (TDS) builds up finally reaching a concentration level where
the operation of the boiler becomes impossible. Surface blow down is removed from the steam drum at the
top of the boiler and Bottom blow down is removed from the mud drum at the bottom of the boiler.
3.27 Soot Blower:
A soot blower is a device for removing the soot that is deposited on the furnace tubes of
a boiler during combustion. Steam pressure is 27 Kg/Cm2
and temperature is 330 .Soot deposited on the
heating surfaces of a boiler acts as a heat insulator. The result is that less heat is transferred to the water to
raise steam and more heat is wasted up the chimney. This leads to higher fuel consumption and efficiency
reduced.
Fig. 3.16 Soot Blower

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3.28 Chimney:
Exhaust temperature of chimney is 150⁰C and height is 200 meters.
Fig. 3.17 Chimney
3.29 Preventing Cold End Corrosion in a Boiler:
Boilers generating steam for use in power generation and process power plants use different type of fuels.
These fuels contain sulphur to differing percentages. The higher the percentage of sulphur, the higher will
be the risk of cold end corrosion in the boiler. The sulphur in the fuel during combustion gets converted to
sulphur dioxide. Depending upon the other impurities present in the fuel and excess air levels, some
portion of the sulphur dioxide gets converted to sulphur trioxide. The presence of moisture in the flue gas
due to moisture in fuel and air, sulphur dioxide, and trioxide, combines with moisture and forms sulphuric
acid and sulphuric acid. These acids condense from around 115 degree centigrade to slightly higher than
160 degrees, depending upon the concentration of SO3 and water-vapour. The basic reactions taking place
are
S + O2 → SO2
SO2 + O2 ↔ SO3
H2O + SO2 ↔ H2SO3
H2O + SO3 → H2SO4
Depending upon the ppm of SO3 and water-vapor concentration, the dew point temperature can vary from
around 90 degree centigrade to 140 degree centigrade. Condensation of these acids results in metal wastage
and boiler tube failure, air preheater corrosion, and flue gas duct corrosion. In order to avoid or reduce the
cold end corrosion the gas temperature leaving the heat transfer surface in boiler is kept around 150
degrees centigrade, ranging from 120 to 155. It is very important that the metal temperature of the tubes is
always kept above the condensation temperature. It may be noted that the metal temperature of the tubes is
governed by the medium temperature of the fluid inside the tubes. This makes it necessary to preheat water
to at least 150 degrees centigrade before it enters the economizer surface. In the case of an air pre-heater,

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two methods are used to increase the metal temperature. One is an air bypass for air pre-heater, and the
second is using a steam coil air pre-heater to increase the air temperature entering the air pre-heater.
The amount of SO3 produced in boiler flue gas increases with an increase of excess air, gas temperature,
residence time available, the amount of catalysts like vanadium pent oxide, nickel, ferric oxide, etc., and
the sulphur level in fuel. The flue gas dew point temperature increases steeply from 90 degree centigrade to
135 degrees centigrade with sulphur percentage increasing up to 1%. A further increase in sulphur
percentage in fuel gradually increases the dew point temperature from 135 degree centigrade to 165
degrees centigrade at 3.5% sulphur in fuel.
3.30 Steps To Reduce Cold End Corrosion:
The in-combustion reduction methods include:
 Burning low sulphur fuel
 Low excess air burners
 Fuel additives
 Fluidized bed combustors
The post-combustion technologies adopted are:
 Designing with higher exit gas temperature
 Air bypass across air pre-heater
 Ammonia injection
3.31 Losses in Boilers: (ASME Standard sec. 4.1)
1) Loss due to dry flue gas = 4.928%
2) Loss due to Un burnt Carbon = 0.331%
3) Due to Sen. Heat of Bottom Ash = 0.071%
4) Due to Sen. Heat of Fly Ash = 0.102%
5) Radiation Losses = 0.200%
6) Loss due to moisture in Fuel = 1.263%
7) Loss due to Hydrogen in Fuel = 5.537%
8) Loss due to Moisture in Air = 0.074%
9) Unaccounted Losses = 1.327%
Total Losses = 13.83%
3.32 Boiler Efficiency:
It is a term which establishes a relationship between energy supplied to the boiler and energy output
received from the boiler. It is usually expressed in percentage. As a general rule, “boiler efficiency (%) =
heat exported by the fluid (water, steam) / heat provided by the fuel x 100."
3.32.1 Indirect Method:
Boiler Efficiency by indirect method = 100 – (losses mentioned above)
3.32.2 Direct Method:
This is also known as ‘input-output method’ due to the fact that it needs only the useful output (steam) and
the heat input (i.e. fuel) for evaluating the efficiency. This efficiency can be evaluated using the formula.

35 | P a g e
Q--Quantity of steam generated per hour in kg/hr.
q--Quantity of fuel used per hour in kg/hr.
GCV--gross calorific value of the fuel in kcal/kg of fuel
Hg—Enthalpy of saturated steam in kcal/kg of steam
Hf—Enthalpy of feed water in kcal/kg of water
3.33 Valve:
A device for controlling the passage of fluid or air through a pipe, duct, etc. especially an automatic device
allowing movement in one direction only.
3.33.1 Types of Valve:
3.33.1.1 Gate Valve:
Gate valves (also known as knife valves or slide valves) are linear motion valves in which a flat closure
element slides into the flow stream to provide shut-off.
These valves are used to control high pressure and also prevent leakage. A drawback of this valve is it
operates slowly.
(a) (b)
Fig.3.18 (a) Gate Valve (B) Parts of Gate Valve

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(c)
Fig.3.18 (c) Gate Valve drawing symbol
3.33.1.2 Globe Valve:
A Globe valves is a linear motion valve and are primarily designed to stop, start and regulate flow. The
disk of a Globe valve can be totally removed from the flow path or it can completely close the flow path.
These valves operate quickly.
(a) (b)
(c)
Fig.3.19 (a) Globe Valve (B) Parts of Globe Valve (c) Drawing Symbol of Globe Valve
3.33.1.3 Pressure Relief Valve:
It is the term used to describe relief device on a liquid filled vessel. For such a valve the opening is
proportional to increase in the vessel pressure. Hence the opening of valve is not sudden, but gradual if the
pressure is increased gradually. It does not release the liquid in to the atmosphere.

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Fig.20 Pressure Relief Valve
3.33.1.4 Pressure Safety Valve:
It is the term used to describe relief device on a compressible fluid or gas filled vessel. For such a valve the
opening is sudden. When the set pressure of the valve is reached, the valve opens almost fully. It releases
the liquid in to the atmosphere.
Fig.21 Pressure Safety Valve

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CHAPTER 4
TURBINE SECTION
4.1 Steam Turbine:
Turbine is used to convert the heat energy into mechanical energy. Turbine used in T.P.S Muzaffargarh is
impulse-reaction steam turbine. The load requirement is controlled by the steam flow through a governing
valve. Maximum steam at full load is 670t/h. When the load at generator is suddenly decreased then the
rpm (frequency) of the generator is increased and to decrease the frequency we lower down the steam flow
which decreases the speed and maintains the frequency. If load is suddenly increased rotor speed becomes
slower, to increase the speed, steam flow is increased.
Large steam turbines are all of the axial-flow type. They may use single flow, double flow or reversed flow
where blades are not shown). Double flow avoids excessively long blades and can reduce axial thrust.
Steam enters and leaves cylinder radially, so design must leave space for flow to turn to axial direction
with minimum losses. The limit of a single-cylinder turbine is about 100 MW. Multi-cylinder designs are
used in large plant, e.g. one high pressure (HP) turbine, one intermediate pressure (IP) turbine and two low
pressure (LP) turbines. IP and LP turbines are usually double flow. There are two basic types of turbine
according to mode of steam.
Fig. 4.1 Multi Stage Steam Turbine
4.2 Impulse Turbine:
It runs by Impulse of steam. Nozzle directs the steam on the curved blades, which causes them to rotate.
The blades are in the shape of buckets. The steam then strikes the rotating blades and performs work on
them, which in turn decreases the velocity (kinetic energy) of the steam. The energy to rotate an impulse
turbine is derived from the kinetic energy of the steam flowing through the nozzle. The steam then passes

39 | P a g e
through another set of stationary blades which turn it back to the original direction and increases the
velocity again though nozzle action. The potential energy is converted into kinetic energy when it passes
through the nozzle. The velocity of steam is reduced when it passes over the blades.
4.2.1 Velocity Compounding of Impulse Turbine:
The velocity compounded Impulse turbine was first proposed by C G Curtis to solve the problem of single
stage Impulse turbine for use of high pressure and temperature steam. The rings of moving blades are
separated by rings of fixed blades.
Fig. 4.2 Schematic Diagram of Velocity Compounded Impulse Turbine
The moving blades are keyed to the turbine shaft and the fixed blades are fixed to the casing. The high
pressure steam coming from the boiler is expanded in the nozzle first. The Nozzle converts the pressure
energy of the steam into kinetic energy. It is interesting to note that the total enthalpy drop and hence the
pressure drop occurs in the nozzle. Hence, the pressure thereafter remains constant.
This high velocity steam is directed on to the first set (ring) of moving blades. As the steam flows over the
blades, due the shape of the blades, it imparts some of its momentum to the blades and loses some velocity.
Only a part of the high kinetic energy is absorbed by these blades. The remainder is exhausted on to the
next ring of fixed blade. The function of the fixed blades is to redirect the steam leaving from the first ring
of moving blades to the second ring of moving blades. There is no change in the velocity of the steam as it
passes through the fixed blades. The steam then enters the next ring of moving blades; this process is
repeated until practically all the energy of the steam has been absorbed.
A schematic diagram of the Curtis stage impulse turbine, with two rings of moving blades one ring of fixed
blades is shown in figure below. The figure also shows the changes in the pressure and the absolute steam
velocity as it passes through the stages.

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Where?
Pi = pressure of steam at inlet
Vi = velocity of steam at inlet
Po = pressure of steam at outlet
Vo = velocity of steam at outlet
In the figure there are two rings of moving blades separated by a single of ring of fixed blades. As
discussed earlier the entire pressure drop occurs in the nozzle, and there are no subsequent pressure losses
in any of the following stages. Velocity drop occurs in the moving blades and not in fixed blades.
4.2.2 Pressure Compounding Of Impulse Turbine:
The pressure compounded Impulse turbine is also called as Rateau turbine, after its inventor. This is used
to solve the problem of high blade velocity in the single-stage impulse turbine. It consists of alternate rings
of nozzles and turbine blades.
Fig 4.3 Schematic Diagram of Pressure compounded Impulse Turbine
The nozzles are fitted to the casing and the blades are keyed to the turbine shaft. In this type of
compounding the steam is expanded in a number of stages, instead of just one (nozzle) in the velocity
compounding. It is done by the fixed blades which act as nozzles.
The steam expands equally in all rows of fixed blade. The steam coming from the boiler is fed to the first
set of fixed blades i.e. the nozzle ring. The steam is partially expanded in the nozzle ring. Hence, there is a
partial decrease in pressure of the incoming steam. This leads to an increase in the velocity of the steam.
Therefore the pressure decreases and velocity increases partially in the nozzle. This is then passed over the
set of moving blades. As the steam flows over the moving blades nearly all its velocity is absorbed.
However, the pressure remains constant during this process. After this it is passed into the nozzle ring and

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is again partially expanded. Then it is fed into the next set of moving blades, and this process is repeated
until the condenser pressure is reached. It is a three stage pressure compounded impulse turbine. Each
stage consists of one ring of fixed blades, which act as nozzles, and one ring of moving blades. As shown
in the figure pressure drop takes place in the nozzles and is distributed in many stages. The inlet steam
velocities to each stage of moving blades are essentially equal. It is because the velocity corresponds to the
lowering of the pressure.
4.3 Reaction Turbine:
It has no nozzle. Two rows of moveable blades are separated by one row of fixed blades. Fixed blades are
attached to the casing & act as nozzles. Blades are like the wings of a plane. A reaction stage has a higher
blade aerodynamic efficiency than an impulse stage, but tip leakage losses are higher because of the
pressure drop across the rotating stage. This is significant for short blades (HP) but becomes insignificant
for long blades (LP). Velocity of steam is increased when it passes through the fixed blades. Three steam
turbines are used in TPS Muzaffargarh with one shaft coupled. These turbines are working on the base of
Charles and boils law.
4.3.1 Pressure Compounding of Reaction Turbine:
As explained earlier a reaction turbine is one which there is pressure and velocity loss in the moving
blades. The moving blades have a converging steam nozzle. Hence when the steam passes over the fixed
blades, it expands with decrease in steam pressure and increase in kinetic energy.
Fig. 4.4 Schematic Diagram of Pressure Compounded Reaction Turbine
This type of turbine has a number of rings of moving blades attached to the rotor and an equal number of
fixed blades attached to the casing. In this type of turbine the pressure drops take place in a number of
stages. The steam passes over a series of alternate fixed and moving blades. The fixed blades act as nozzles
i.e. they change the direction of the steam and also expand it. Then steam is passed on the moving blades,
which further expand the steam and also absorb its velocity.

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4.4 Turbine Description:
4.4.1 Turbine Model:
K.210.130.8
K stands for condensed, 210 is MW, 130 is pressure in Kg/Cm2
while 8 is model number.
4.4.2 HP (High Pressure) Turbine:
First of all steam from boiler comes into the HP turbine. Steam in the HP turbine is called live steam or
main steam. Rotor blades diameter of this part of turbine is smallest of the other parts of the turbine .Inlet
steam temperature of the HP turbine is 545 °C and pressure is 130 Kg/cm2
. Outlet steam temperature of the
HP turbine is 332°C and pressure is 28.1 Kg/cm2
. HP turbine has total of 12 stages including one is
governing stage. The flow of steam is 640 ton/h.
4.4.3 IP (Intermediate Pressure) Turbine:
Steam comes into IP turbine from HP turbine via re-heaters. The steam inlet pressure in this section of
turbine is 26 Kg/cm2
and temperature is 540°C. This part has total of 11 pressure stages. The flow of steam
is 590 ton/h.
4.4.4 LP (Low Pressure) Turbine:
The outgoing steam of the IP turbine entered into the LP turbine. Steam from the LP turbine goes in to the
condenser. The steam inlet pressure of this section of turbine is 1.26 Kg/cm2
and the temperature is 3800
C
and out let temperature is 600
C.
4.5 Reheater:
Power plant furnaces may have a reheater section containing tubes heated by hot flue gases outside the
tubes. Exhaust steam from the high pressure turbine is passed through these heated tubes to collect more
energy before driving the intermediate and then low pressure turbines.
4.5.1 Reheat Cycle:
Fig.4.5 Reheat Cycle

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4.6 Live Steam Cycle:
Fig.4.6 Live Steam Cycle

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4.7 Parts of Turbine:
 Casing  Fixed Blade
 Moving Blade  Governing Valves
 HP Turbine  LP Turbine
 IP Turbine  Turbine Rotor
 General Bearing  Thrust Bearing
Table 4.1 Parts of Turbine
4.7.1 Turbine Casings:
A turbine casing (cylinder) is a high pressure vessel with its weight supported at each end on the horizontal
centerline. It is designed to withstand stresses in the transverse plane and to be stiff in the longitudinal
direction to maintain accurate clearances between the stationary and rotating parts. Casings are split along
the horizontal centerline to allow internal access and insertion of the rotor as a complete assembly. High
pressures necessitate very thick flanges and bolting.
The temperature of these changes more slowly than the rest of the casing during start-up so a flange
warming system is used. HP and IP casings are cast. LP casings can contain some fabrication. Casings are
tested to 150% of highest working pressure.
4.7.2 Turbine Rotors:
The shaft of each turbine rotor is a single, high quality alloy steel forging, machined to provide the
required contours and functioning parts. Each end contains an integral coupling, gland seal area and
bearing area. For HP and IP reaction turbines, axial grooves are machined into the rotor for the blades. For
impulse HP and IP turbines and for LP turbines, wheels are machined or shrink fitted onto the rotor with
the blades mounted in grooves in the wheels. Alloy steels are chosen to have good creep resistance and
high temperature and high fracture toughness.
The rotors of HP and IP turbines may have a center bore machined in the shaft to remove impurities
formed during the forging, and to allow access for ultrasonic inspection.
4.7.3 Journal Bearing:
Journal or plain bearings consist of a shaft or journal which rotates freely in a supporting metal sleeve or
shell. There are no rolling elements in these bearings. The bearing metal temperatures are measured by
thermocouples directly under. Oils are used in journal bearings when cooling is required or contaminants
or debris need to be flushed away from the bearing. High-speed journal bearings are always lubricated with
oil rather than grease.
4.7.4 Thrust Bearings:
The purpose of the turbine thrust bearing is to provide a positive axial location for the turbine rotors
relative to the cylinders. To achieve this, it must be able to withstand the unbalanced thrusts due to blade
reaction and steam pressure acting on unbalanced areas.

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It is normally located close to the areas where blade cylinder clearances are minimum and operating
temperatures are highest.
Fig.4.7 Thrust Bearing
4.8 Axial Shift:
The axial shift is the measure of axial displacement of the shaft within the thrust bearing. Axial shift is set
at zero when thrust is at the center of the axial clearance at the thrust pads. Axial shift towards generator is
positive and towards HP side is negative. Alarm and tripping is provided when the axial shift reading
exceeds the set value.
Axial Shift Displacement (Take0 Reference)
+Ve side 0.8mm alarm & 1.omm tripping
-Ve side 1.0mm alarm & 1.2 mm tripping
4.9 Barring Gear:
Barring gear (or “turning gear”) is the mechanism provided to rotate the turbine generator shaft at a very
low speed after unit stoppages. Once the unit is “tripped” (i.e., the steam inlet valve is closed), the turbine
coasts down towards standstill. When it stops completely, there is a tendency for the turbine shaft to
deflect or bend if allowed to remain in one position too long. This is because the heat inside the turbine
casing tends to concentrate in the top half of the casing, making the top half portion of the shaft hotter than
the bottom half. The shaft therefore could warp or bend by millionths of inches. This small shaft
deflection, only detectable by eccentricity meters, would be enough to cause damaging vibrations to the
entire steam turbine generator unit when it is restarted. The shaft is therefore automatically turned at low
speed (about one percent rated speed) by the barring gear until it has cooled sufficiently to permit a
complete stop.
4.10 Gland Sealing System:
The two functions of the turbine glands and seals are:
1. To prevent or reduce steam leakage between the rotating and stationary components of the turbines
if the steam pressure is higher than atmospheric.

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2. To prevent or reduce air ingress between the rotating and stationary components of the turbines if
the steam pressure is less than atmospheric. The last few stages in the low-pressure (LP) turbines
are normally under vacuum.
4.11 Blade Materials:
Blade material must have some or all of the following properties, depending on the position and role.
 Corrosion resistance (especially in the wet LP stage)
 Tensile strength (to resist centrifugal and bending stresses)
 Ductility (to accommodate stress peaks and stress concentrations)
 Impact strength (to resist water slugs)
 Material damping (to reduce vibration stresses)
 Creep resistance
12% Cr stain less steels are a widely used material. Their weakness is at very high temperatures (> 480C).
A typical high temperature steel is 12% Cr alloyed with molybdenum and vanadium (to 650C). Titanium
has some attractions but it is expensive and material damping is low. It has poor vibration characteristics.
Because of its high strength/weight ratio, titanium is used in lacing wire and for cover bands and
shrouding.
Over speed:
10% tolerance of rated speed (rated speed 3000 rpm)
4.12 Condenser:
The condenser condenses the steam from the exhaust of the turbine into liquid to allow it to be pumped. In
TPS Muzaffargarh surface type condenser is used. The surface condenser is a shell and tube heat
exchanger in which cooling water is circulated through the tubes. The exhaust steam from the low pressure
turbine enters the shell where it is cooled and converted to condensate e (water). The cooling water is
return to the cooling tower and condensate is collected in hot well.
Fig.4.8 Surface Condenser

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This extracts the greatest amount of energy from the steam to maximize the power output of the turbine.
The steam, at this low pressure (vacuum) condenses at 65°C. The condenser operates under high vacuum
which occurs due to the condensing of the steam. (This causes a huge volume decrease in that the water,
when converted to steam expands by 1,800 times. When condensing, it therefore occupies a volume 1,800
times LESS as water). The water formed is pumped back to the Boilers for re-use. The Cooling towers
don't cool this water as its treated water specifically used for steam generation. A separate Cooling Water
System is used for the surface condensers and other heat exchange (cooling) systems throughout the Power
Station. It's this water that is cooled by the towers and is also recycled from the tower collecting basin to
the Cooling Water distribution pumps.
4.13 Condensate Pump:
Condensate pump receive condensate from the hot well and transfer to steam air ejector. Pressure of
condensate rises in condensate pump up to 15 kg/cm2
. The total number of condensate pumps 3.
4.14 Steam Air Ejector:
A device that removes air and other gases from steam condensers through the suction action of a
steam jet. Steam air ejector is used to rise the temperature of condensate. Condensate water
flows through the tubes and steam around the tubes.
4.15 Gland Steam Condenser:
Bleed off stem from turbine bottom goes to gland steam condenser. Gland steam condenser also accepts
leak off steam from main steam stop valves and control valves. The stem in gland steam condenser is
condensed by cooling water and transferred to main condenser.
4.16 L.P Heaters:
L.P Heaters are used to increase the temperature of condensate. Temperature of condensate is increased by
steam bleedings. Bleedings are extracted from different stages of turbine as described below:
Stage No. Heater No:
25 of (L.P Turbine) L.P Heater 1
23 of (I.P Turbine) L.P Heater 2
Table 4.2 L.P Heater Bleedings

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4.17 Condensate Cycle Diagram:
Fig.4.9 Condensate Cycle

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4.18 Dearator:
A deaerator is a device that is widely used for the removal of oxygen and other dissolved gases from
the feed water to steam-generating boilers. In particular, dissolved oxygen in boiler feed waters will cause
serious corrosion damage in steam systems by attaching to the walls of metal piping and other metallic
equipment and forming oxides (rust). Dissolved carbon dioxide combines with water to form carbonic
acid that causes further corrosion. Most deaerators are designed to remove oxygen down to levels of
7 ppb by weight (0.005 cm³/L) or less as well as essentially eliminating carbon dioxide.
Fig.4.10 Dearator
4.19 Boiler Feed Water Tank:
It is an essential part of boiler operations. The feed water is put in to the steam drum from a feed pump. In
the steam drum the feed water is then turned into steam from the heat. After the steam is used it is then
dumped to the main condenser. From the condenser it is then pumped to the deaerated feed tank. From this
tank it then goes back to the steam drum to complete its cycle. The feed water is never open to the
atmosphere.
4.20 Feed Water Pump:
A boiler feed water pump is a specific type of pump used to pump feed water into a steam boiler. Feed
water pump is high pressure centrifugal pump having 11 stages. Inlet pressure of water is 8kg/cm2
and out
let pressure is up to 190kg/cm2
.

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4.20.1 Parts of Feed Water Pump:
4.20.1.1 Impeller and Diffuser:
A centrifugal pump is of very simple design. The only moving part is an impeller attached to a shaft that is
driven by the motor. The two main parts of the pump are the impeller and diffuser. The impeller can be
made of bronze, stainless steel, cast iron, polycarbonate, and a variety of other materials. A diffuser or
volute houses the impeller and captures the water off the impeller.
Fig.4.11 Boiler Feed Water Pump Impeller Diffuser
Water enters the eye of the impeller and is thrown out by centrifugal force. As water leaves the eye of the
impeller a low pressure area is created causing more liquid to flow toward the inlet because of atmospheric
pressure and centrifugal force. Velocity is developed as the liquid flows through the impeller while it is
turning at high speeds on the shaft. The liquid velocity is collected by the diffuser or volute and converted
to pressure by specially designed passageways that direct the flow to discharge into the piping system; or,
on to another impeller stage for further increasing of pressure.
The head or pressure that a pump will develop is in direct relation to the impeller diameter, the number of
impellers, the eye or inlet opening size, and how much velocity is developed from the speed of the shaft
rotation. Capacity is determined by the exit width of the impeller. All of these factors affect the
horsepower size of the motor to be used; the more water to be pumped or pressure to be developed, the
more energy is needed. A centrifugal pump is not positive acting. As the depth to water increases, it
pumps less and less water. Also, when it pumps against increasing pressure it pumps less water. For these
reasons it is important to select a centrifugal pump that is designed to do a particular pumping job. For
higher pressures or greater lifts, two or more impellers are commonly used; or, a jet ejector is added to
assist the impellers in raising the pressure.

51 | P a g e
(a) (b)
Fig.4.12 (a) Diffuser (b) Impeller
4.20.1.2 Hydraulic Coupling:
A fluid coupling or hydraulic coupling is a hydrodynamic device used to transmit rotating mechanical
power. It has been used in automobile transmissions as an alternative to a mechanical clutch. It also has
widespread application in marine and industrial machine drives, where variable speed operation and
controlled start-up without shock loading of the power transmission system is essential.
Fig.4.13 Hydraulic Coupling

52 | P a g e
4.20.1.3 Balance Disk:
In any centrifugal pump, each impeller tends to produces some amount of thrust because of different
pressures and different geometries on the two sides of the impeller. In a high pressure multi-stage pump
(such as BFW) the number of impellers is high, thus the net thrust would be large unless something is done
to balance it out. The two main ways to reduce the net thrust are to oppose the impellers or to use a
balance disk. For axial split pumps, it is usually most economical to oppose the impellers. About half of
the stages are oriented with the suction pointing toward the coupling and the rest are oriented with the
suction toward the thrust bearing. The thrust of the stages pointed in opposite directions tend to cancel
out. The net thrust that the thrust bearing must take is much smaller than it would be if they all pointed in
the same direction. But axial split cases tend to have an upper pressure limit. At very high pressures,
barrel pumps are used since they can handle the very high pressures better. With a barrel pump, it is much
more difficult to find a good way to direct the flow path through a set of opposed impellers. So instead,
they point all the impellers in the same direction and use a balance disk or drum on the end. The balance
disk is just after the last stage so it has full discharge pressure on one side. A line is routed from the other
side of the balance disk back to the suction. The size of the drum is made so that it provides almost as
much net thrust as all the impellers combined. Area time’s pressure difference between suction and
discharge equals thrust force. Since there is a very high pressure differential across the balance disk/drum,
it is critical that the clearances are correct or else excessive flow will be diverted back to suction and the
thrust balancing force will be lost. In other words, if the balance drum fails, a thrust bearing failure is
likely to follow.
4.20.1.4 Mechanical Seal:
A mechanical seal is a device that helps join systems or mechanisms together by preventing leakage (e.g.
in a plumbing system), containing pressure, or excluding contamination. The effectiveness of a seal is
dependent on adhesion in the case of sealants and compression in the case of gaskets.
Fig.4.14 Mechanical Seal

53 | P a g e
4.21 H.P Heaters:
H.P Heaters are placed between feed water pump and economizer. These are used to increase the
temperature of feed water. Bleedings are extracted from different stages of turbine as described below:
Stage No. Heater No:
15 of (I.P Turbine) H.P Heater 5
12 of (H.P Turbine) H.P Heater 6
09 of (H.P Turbine) H.P Heater 7
Table 4.3 H.P Heater Bleedings
4.22 Feed Water Cycle:
Fig.4.15 Feed Water Cycle

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CHAPTER 5
COOLING TOWER SECTION
5.1 Cooling Tower:
Cooling towers are a special type of heat exchanger that allows water and air to come in contact with each
other to lower the temperature of the hot water. During this process, small volumes of water evaporate,
lowering the temperature of the water that's being circulated throughout the cooling tower. In a short
summary, a cooling tower cools down water that gets over heated by industrial equipment and processes.
Fig.5.1 Cooling Tower
For Unit (1,2,3)
Total Cooling Tower 6 Total Fan 48
For Each Unit 2 For Each Tower 8
5.2 Working:
The hot water is usually caused by air conditioning condensers or other industrial processes. That water is
pumped through pipes directly into the cooling tower. Cooling tower nozzles are used to spray the water
onto to the "fill media", which slows the water flow down and exposes the maximum amount of water
surface area possible for the best air-water contact. The water is exposed to air as it flows throughout the
cooling tower. The air is being pulled by a motor-driven electric "cooling tower fan".
When the air and water come together, a small volume of water evaporates, creating an action of cooling.
The colder water gets pumped back to the process/equipment that absorbs heat or the condenser.

55 | P a g e
5.3 Types of Cooling Tower:
5.3.1 Crossflow CoolingTowers:
In Crossflow cooling towers the water vertically flows through the fill media while the air horizontally
flows across the falling water. That's why they call it "cross flow" because the air and water cross paths or
flows. Because of the crossing of flows, the air doesn't need to pass through the distribution system. This
permits the use of hot water flow via gravity and distribution basins on the top of the tower right above the
fill media. The basins are a standard of Crossflow cooling towers and are applied on all units.
Fig.5.2 Cross Flow Cooling Tower
5.3.2 Counter Flow CoolingTowers:
In counter flow cooling towers, the air vertically flows upwards, counter to the water flow in the fill media.
Due to the air flowing vertically, it's not possible to use the basin's gravity-flow like in Crossflow towers.
As a substitute, these towers use pressurized spray systems, usually pipe-type, to spray the water on top of
the fill media. The pipes and cooling tower nozzles are usually spread farther apart so they will not restrict
any air flow.
Fig.5.3 Counter Flow Cooling Tower

56 | P a g e
5.3.3 Forced Draft Cooling Towers:
In this system, fan is located near the bottom and on the side. This fan forces the air from bottom to top.
An eliminator is used to prevent loss of water droplets along with the forced air.
Fig.5.3 Force Draft Cooling Tower
5.3.4 Induced Draft:
A mechanical draft cooling tower with a fan at the discharge which pulls air through tower. The fan
induces hot moist air out the discharge. This produces low entering and high exiting air velocities,
reducing the possibility of recirculation in which discharged air flows back into the air intake.
Fig.5.4 Induce Draft Cooling Tower

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5.3.5 Natural Draft:
Utilize buoyancy via a tall chimney. Warm, moist air naturally rises due to the density differential
compared to the dry, cooler outside air. Warm moist air is less dense than drier air at the same pressure.
This moist air buoyancy produces an upwards current of air through the tower.
Fig.5.5 Natural Draft Cooling Tower
5.4 Cooling Tower Fill Types:
5.4.1 Fill:
It has been seen that most cooling towers are equipped with fills, either made up of plastic or wood. The
fill employed for easy transfer of heat by maximizing water and air contact.
5.4.2 Film Fill:
Cooling tower consists of thin, closely placed plastic surfaces over which the water spreads forming a thin
film in contact with air. The surface may be flat, corrugated etc.
Fig.5.6 Film Fill Design

58 | P a g e
5.4.3 Splash Fill:
Cooling Tower consists of layers of horizontal splash bars into which the water spreads and breaks into
small droplets. Since the water falls over successive layers the fill surface also get wet. In most of the
cases, plastic splash fill provides better heat transfer as compared to the wood splash fill.
Fig.5.7 Splash Fill Design
5.5 Circulating Water Pump:
This is the pump to send cooling water to the condenser. It receives water from for bay. Before sending
water to the condenser water is passed through a screen filter to remove impurities .circulating water pump
is centrifugal pump having vertical shaft.
5.5.1 C.W.P Motor Specifications:
Type Y1600-12/2150
Rated Current 182A
Rated Speed 372 RPM
Rated Power 1600KW
Rated Frequency 50Hz
Capacity 16000m3
/H
Power Factor .9
Table 5.1 C.W.Pump Motor Specifications
The motor of pump is oil cooled and air cooled .Stator winding connection is Y. the rated frequency is 50
Hz and no. phases are 3. Water from the circulating water pump is passed through these pipes it consist of
ideal flow gate valve during start of pump this valve remain open until non return valve is not fully open.

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As non-return valve fully open this valve will be closed. Vent valve is used to remove bubbles and air from
pipe line this is low pressure and high discharge flow pump.
Fig.5.9 Cooling Water Pipes

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CHAPTER 6
CHEMICAL WATER TREATMENT AND PLANT HEAT RATE
6.1 Chemical Water Treatment:
There are two ways of chemical water treatment
6.1.1 External Treatment:
External treatment is the reduction or removal of impurities from water outside the boiler. In general,
external treatment is used when the amount of one or more of the feed water impurities is too high to be
tolerated by the boiler system in question.
6.1.2 Internal Treatment:
Internal treatment is the conditioning of impurities within the boiler system. The reactions occur either in
the feed lines or in the boiler proper. Internal treatment may be used alone or in conjunction with external
treatment. Its purpose is to properly react with feed water hardness, condition sludge, scavenge oxygen and
prevent boiler water foaming.
6.2 Water Purification System:
For the making of steam and for the cooling of generators only the pure H2O water is used
because, impure particles in this water causes
1- Vibrations in the turbines and damage its blades.
2- Corrosion inside the pipes.
3- Electrical conductivity between the generator windings.
To purify the water from makeup tank there is a water treatment plant, where this water passes through
different stages to remove its impurities. The block diagram of this plant is given below. The raw water in
this plant passes from 6 different stages which are:
1. Mechanical Filters
2. 1stStage of Cation Filter
3. De-Gassifier
4. Anion Filter
5. 2nd Stage of Anion Filter
6. Mixed Bed Filter
6.2.1 Mechanical Filters:
First of all, raw water enters in these filters. Four filters are installed for this purpose, in which two of them
are functional while other two are for stand-by use. Each tank has the capacity of 45T/h.
6.2.2 Cation Filter # 1:
Clarify water passed through cation bed exchanger –ve charge disappear is called cation. To removing the
cation salts like ( Ca+2, Mg+2, Na+1 ),this water passes through cation filter, where it interacts with
hydrogen ions H+. These hydrogen ions replace the other cations from their salts and removed in this
stage.

61 | P a g e
6.2.3 De-Gassifier:
De- gassifier or de- carbonizes are used to remove CO2 gas from the water. For this purpose there are two
main chambers where water is showering from the top and air is entered form the bottom by fans. This air
interacts with the carbon ions in water and makes CO2 gas, which moves out from the top side of chamber.
And the water collected in the storage tank, located below the chamber.
6.2.4 Anion Filter:
Calorify water is passed through anion bed exchanger +ve charge disappear. Water is sent to anion filter
form decarbonized water tank, using pumps. There are four filters in which one is used and other are for
backup. Each filter has capacity of 90T/h. Na OH is introduced in water to remove silica and other anions.
6.2.5 Cation Filter # 2:
If any amount of cations remain in water even after cation filter, these filters remove those
cations. 98% pure H2SO4 is added in this filter to provide more H+ ions.
6.2.6 Mixed Bed Filter:
This is the last stage of water treatment procedure. It has the capability to remove both cations and anions
from water. They have a very good efficiency.
6.2.7 Demineralized Water Tank:
After passing through the filters, water is sent to the demi water storage tank. This water has no hardness
and all other minerals values in tolerable ranges. Three tanks are available, each with the capacity to store
2000 metric ton water. This water is supplied through pumps to the makeup connection after hot well to
fulfill the demand of unit.
Fig.6.1 Water Treatment Plant Diagram

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6.3 What is Heat Rate?
Heat Rate is the common measure of system efficiency in a steam power plant. It is defined as "the energy
input to a system, typically in Btu/kWh, divided by the electricity generated, in kW." Mathematically:
Efficiency is "a ratio of the useful energy output by the system to the energy input to the system."
Mathematically:
As you can see, heat rate is simply the inverse of efficiency. With that in mind, if you increase plant
efficiency, which is good, then you would lower heat rate. What this means is that the lower the heat rate,
the better your plant is running and, therefore, the more competitive it is. As you can see by the equations,
efficiency has no units, but heat rate does. That is because with heat rate, you typically are measuring the
chemical energy input and the electrical energy output, and this will leave you with the units of BTU/kWh.
6.4 Plant Heat Rate:
Plant heat rate is a measure of the combined performance of the steam turbine cycle, and any other
associated auxiliaries. This may include more than one steam turbine. Heat rate can be further divided to
compare units at the same plant, where you might compare Power Block 1 to Power Block 2. You may
even use heat rate to compare to other generating units at different sites. Caution must be taken when
comparing different types of generating stations, as their chemical energy input may be quite different
from yours.
Chemical Energy of Fuel = Total Fuel Used (scf/hr) x Higher Heating Value
(HHV)(BTU/scf)
The power generated is simply the gross or net generation in kW.
If gross generation is used, then the resultant heat rate is the gross unit heat rate.
If net generation is used, then the resultant heat rate is net unit heat rate.
By substituting from the previous equations we get:
Unit analysis is very important. At many sites, fuel flow is measured in lbm/hr, and HHV is given in scf/hr.
It is very important to make sure that you match units when doing these problems.
6.5 Why is Heat Rate Important?
Heat rate and thermal performance improvement are integral parts of any serious effort for cost
containment in an electric generating station. As the electric power industry expands deregulation and
competition, cost containment and the ability to provide energy at the lowest possible cost become

63 | P a g e
important issues. The power producer must provide a lower-cost energy product than the competition and
yet still remain profitable in the long term. Fuel-cost reduction and increased reliability and availability
through efficiency improvement are key methods of improving profitability.
In many generating stations, fuel expenditure is as high as 90% of the total operations budget. As a result,
a 1% reduction in fuel usage achieved through heat rate improvements has a significant, positive impact on
profitability. For a 500 MW combined cycle unit, the annual fuel savings could easily exceed $1,500,000
by simply improving heat rate by 200 units. Heat rate improvement requires the support of personnel at all
levels, in addition to support from both station and corporate management. By monitoring and acting on
many of the items identified here and decreasing the amount of controllable losses, plant heat rate can be
improved to an optimum level and maintained at that optimum level. Controllable losses, often called
operator controllable losses, are defined as "those heat rate losses that can be directly impacted (either
positively or negatively) by the actions of the operator." In many cases, the actual "control" is handled by
the control system, but often, operator intervention can impact the magnitude of the loss.

64 | P a g e
CHAPTER 7
GENERATOR AND TRANSFORMER
7.1 The Generator:
The generator is a device which converts the mechanical energy into electrical energy.
7.1.1 Working Principle:
The working principle of generator is based on the Faraday's law of electromagnetic induction, which
states that:
"The electromotive force is always produced in conductor which is placed in the magnetic field when there
is a relative motion between conductor and the magnetic field".
Fig.7.1 Generator Working Principle
At a power plant, a GENERATOR is used to make electricity. Inside a generator, a magnet called a
ROTOR spins inside coils of copper wire called a STATOR. And TURBINES are used to spin the rotor
inside the generator. If the output electrical energy is AC, it is called alternator. If the output electrical
energy is DC, it is called DC generator. In fact there is no difference between alternator and Dc generator
except the way the output is obtained from the generator. In alternator the AC supply is produced in the
armature and supply is obtained through slip rings where as in the DC generator are generated AC supply
is obtained from the armature through the spilt rings or commutater which converts the AC into DC. The
following three things are necessary for generation of electrical energy.

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 Magnetic field
 Conductor
 Relative motion between conductor and magnetic field
In this power house the large Generator are used. In the large generator the magnetic field is produced by
the electromagnetic in the rotor and the electromagnetic force is produced in the stator. The output is taken
from the rotor, the rotor must have high insulation due to high voltage induction and it must have heavy
insulation which may increase the size of rotor, and require more power for the prime mover to rotate to
this heavy rotor.
7.1.2 Generator Parameter:
Table 7.1 Generator Parameter
7.1.3 Cooling System of Generator:
The first question arises here is that why we need cooling of the generator? As the current flows in the
stator and rotor of the generator is very high so it increases the temperature of the stator and rotor winding.
As the result the resistance of the stator and rotor windings increases which increase the power losses and
may cause the insulation breakdown. Two types of cooling are used in the turbo generator of TPS phase 1.
• Stator cooling
• Rotor cooling
7.1.3.1 Stator Cooling:
The stator of the turbo generator is cooled by demineralized water. For this purpose a special plant is
installed which prepares the demineralized water for the stator cooling. This demi water is also used for

Internship Report GENCO III TPS Muzaffergarh By Arshad Abbas

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