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1
Internship Report
Of
Northern Power Generation Company Limited
Thermal Power Station Muzaffar Garh(Phase-11)
(Genco-III)
2
Introduction 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, like
ship propulsion. 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.
Commercial electric utility power stations are m9ost usually constructed
on a very large scale and designed for continuous operation. Electric power
plants typically use three phase or individual phase electrical generators
to produce alternating current (AC) electric power at a frequency of 50Hz
or 60Hz depending on its location on the world. Other large companies or
institutions may have their own usually smaller power plants to supply
heating or electricity to their facilities especially if heat or stem is created
anyway for other purposes.
3
Table of contents 1 Introduction 7 2 TPS Muzffar Garh 8 2.1 Installed capacity 8 2.2 Introduction to phase#1 8 2.3 Introduction to phase#2 9
3 Boiler 11 3.1 Water tube boiler 11 3.2 Boiler parameter 11 3.3 Main part of boiler 12 3.4 Boiler protection 16 4 Steam turbine 17
4.1 HP (High pressure) turbine 18 4.2 IP (Intermediate pressure) turbine 18 4.3 LP (Low pressure) turbine 18 4.4 Steam turbine specification 18 4.5 Turbine protection 19
5 FSSS 19 5.1 Decanting area 20 5.2 Fuel oil tanks 20 5.3 First lift pump 20 5.4 Main heaters 21 5.5 Second lift pump 21
6 The generator 22 6.1 Working principle 22 6.2 Main generator parameters 23 6.3 Cooling system of turbo-generator 24 6.4 Protections of generator 27 7 Cycles 29
7.1 Steam cycle 29 7.2 Fuel oil cycle 30 7.3 Air flow cycle 31 7.4 Condensate cycle 32 7.5 Feed water cycle 33
4
1. T.P.S Muzaffar Garh 1.1 Installed capacity
This power station is a vital and major thermal power generating
installation connected with national grid system in Pakistan. This
power station was constructed in different phases having total
capacity of 1370MW. It consists of:
Three Russian units of 210MW each
Two Chinese units of 210MW
One Chinese unit of 320MW
Fuel
Dual fuel combustion provision gas & furnace oil has been made for all
the machines. Furnace oil is transported through railway wagons and
tank Lorries.
Unit# Installed capacity
Working capacity
Constructed By
Construct-ion Date
Fuel Type
ST-1 210MW 170MW Russian Sep.1993 P. Gas, F. oil
ST-2 210MW 175MW Russian Mar.1994 P. Gas, F. oil
ST-3 210MW Shutdown Russian Feb.1995 P. Gas, F. oil
ST-4 320MW 280MW China Dec.1996 P. Gas, F. oil
ST-5 210MW Shutdown China Dec.1995 P. Gas, F. oil
ST-6 210MW Shortage of fuel oil
China Dec.1995 P. Gas, F. oil
Total
1370MW 625MW
Table 1.1 brief views of TPS units
5
2.2 Phase#1 (Unit 1, 2 & 3) This phase consist of three steam units each capable of generating
210MW electricity. The supplier started delivery of equipment to site
in January, 1989 and after pre-assembly of equipment at site,
erection started in July, 1990. Unit#1 was commissioned in
September, 1993 and unit#2 in March, 1994.
Main Building: It contains the turbine hall having a span of 45m and dearator bay,
12m wide. The stem turbines which drive generators are of three
stage condensing type arranged transversely to the axis of turbine
hall. The operational platform is at elevation 12.6m and a
maintenance bay at ground flour near unit#1. The power plant is
designed block principle: boiler-turbine-generator-unit transformer.
The flue gas exhaust section of two units is connected with a 200m
high stack, outer section of which is a 195m high concrete shell.
Combined Auxiliary Building: The building is connected with the main building and it houses
water treatment plant to produce 100t/h dematerialized water for
the replenishment of station losses. Hydrogen plant to provide
hydrogen for cooling of generator's r rotor, maintenance shops,
laboratories, and central control room.
Fuel & Oil Facilities: Fuel oil facilities are constructed for decanting, oil storage,
preparation and supply of fuel to boiler nozzles. It also includes
HSD storage as well as oil facilities for reception, storage,
purification and centralized delivery of turbine oil and insulating oil
to power plant.
Hydraulic Structures: The cooling water used in condensers is re-circulated in closed cycle
with indicated draft cooling towers, the water is being cooled for
each unit in two cooling towers each consisting of eight fans, two
6
cooling towers carry 27,500Cu m/h circulating water for condensers
of one unit.
Startup Boiler: One startup boiler using diesel oil as fuel with steam output of 50t/h
is provided to meet steam requirement for initial start of unit as
well as a backup of power plant auxiliaries. A separate stack of 30m
high has been constructed for it.
Electrical Part: The electricity generated at 15.75 KV is brought out from unit
transformer at 220 KV and feed to the national grid via a switch
yard. Power plant auxiliaries are fed at 6.6 KV.
2.3 Phase#2(Units#5 & 6): It consist of two units of 210MW each having equipment similar to
phase#1. Turbines are placed longitudinally in main building
outdoor boiler exhaust of two units is connected to one stack.
Overview: There are many different types of power plants including thermal
power plants and hydel power plants. Thermal power plants use fuel
such as gas, HSD, furnace oil or nuclear fuel to produce heat energy
that is converted to electrical energy through a series of intermediate
process. Hydel power plants convert the potential energy of water to
electrical power as it follows from higher to lower elevations.
The "traditional" thermal power plant is the Rankin cycle plant
named after the man who invented the cycle. A power plant cycle is
a series of processes in which a fluid generally water/steam, is used
to convert heat energy to mechanical energy. The Rankin cycle in its
simplest form consists of a boiler, a turbine, a condenser and a boiler
feed pump. Early plants had thermal efficiencies of approximately
25% to 30%. Only 25% to 30% of the heat energy in the fuel burned
in these plants was converted to electrical energy. The rest was lost
in various ways. The Rankin cycle has been refined considerably
over the years and made more efficient by the addition of
7
components like economizer, feed water heaters, super heaters and
re-heaters. The efficiency of Rankin cycle has also been improved by
increasing the pressure and temperature of the cycle. The laws of
thermodynamics and considerations such as material limitation
have prevented any significant improvement sense then. Power
plants commonly use heat rate of measure efficiency.
Fuel
Energy
Boiler Heat
Energy
Turbine Mechanica
l energy Generat
or
Electrical
energy
8
3. Boiler 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. The
types of boiler use in the T.P.S phase#2 is "water tube type"
3.1 Water Tube Boilers:
In water tube boilers, boiler water passes through the tubes while the
exhaust gasses remain in the shell side, passing over the tube surface,
since tubes can typically withstand higher internal pressure then the
large chamber shell in a fire tube, water tube boilers are used where
high steam pressure (as high as 3,000Psi) are required.
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.
3.2 Boiler Parameter:
Rated evaporating amount 680t/h
Reheat steam amount 575.8t/h Main steam pressure 140Kg/𝒄𝒎𝟐g Temperature 541°C Outlet pressure of reheat system 23.8 Kg/𝒄𝒎𝟐g
Outlet temperature of reheat system 541°C Inlet pressure of reheat system 25.8 Kg/𝒄𝒎𝟐g Inlet temperature of reheat system 310°C
Feed water temperature 251°C Boiler efficiency (Burn oil) 90.26% Boiler efficiency (Burn gas) 85% Exit gas temperature (Burn oil) 153°C Exit gas temperature (Burn gas) 136°C
Consumption of crude oil 48.2t/h Consumption of natural gas 59650 N𝒎𝟐/h
9
3.3 Main Parts of Boiler:
The boiler consists of following main parts:
1. Force Draft Fan (FDF)
2. Burners
3. Furnace
4. Up Rise Tube
5. Down Comer Tube
6. Water Tube
7. Super Heater
8. Gas Recirculation Fan (GRCF)
9. Re-Heater
10. Induced Draft Fan (IDF)
11. Air Pre-Heater
12. Chimney
13. Boiler Drum
14. Economizer
3.3.1 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.
The air from the FDF is then fed to the regenerative heaters.
The motor of FDF has following specification:
Type KK 800 11-8 Rated voltage 6.6KV Rated current 114/121.3A Rated speed 747rpm
Output 1000KW Connection of stator/rotor Y Insulation class F
10
Permissible rise 80K Ambient temperature 40°C No. of phases 3 Rated frequency 50Hz Power factor 0.81
Degree of protection IP54 Moment of inertia 310 𝑲𝒈𝒎𝟐 Weight 12020/13250 Kg
3.3.2 Induced Draft Fan (IDF):
ID fan sucks the flue gases from the boiler and exhaust through
chimney.
The motor of ID fan has following specifications:
Type KK 800 11-6
Rated voltage 6.6KV Rated current 20A Rated speed 991rpm Rated power 2000KW Connection of stator winding 2Y Insulation class F
Permissible rise 80K Ambient temperature 40°C No. of phases 3 Rated frequency 50Hz Degree of protection IP54 Moment of inertia 410 𝑲𝒈𝒎𝟐
Weight 15970 Kg
3.3.3 Gas recirculation fan (GRCF):
The motor of GRCF has following specification.
11
Type KK 400 11-4 Rated voltage 6.6KV Rated current 34A Rated speed 1491rpm Rated power 315KW
Connection of stator winding Y Insulation class F Permissible rise 70K Ambient temperature 50°C No. of phases 3 Rated frequency 50Hz
Degree of protection IP54 Moment of inertia 11.7 𝑲𝒈𝒎𝟐 Weight 3200 Kg
3.3.4 Cooling Towers:
Cooling towers are heat removal devices used to transform process
waste heat to the atmosphere. Cooling tower may either use the
evaporation of water to remove process heat and cool the working
fluid to near the wet-bulb air temperature or relay solely on air to
cool the working fluid to dry –bulb air temperature. Common
application includes cooling the circulating water used in oil refiner,
chemical plants and power station.
3.3.5 Circulating water pump motor: The motor of the CWP has following specification:
Type Y1600-12/2150 Stator voltage 6.6KV
Rated current 182A Rated speed 372rpm Rated power 1600KW Connection of stator winding 2Y
12
Insulation class B Ambient temperature 50°C No. of phases 3 Rated frequency 50Hz Weight 17500Kg
3.3.6 CW Pump: Type is single stage double suction centrifugal pump.
Type 1400S25-1 Capacity 16000𝒎𝟑/h
Speed 370rpm Power 1600KW Weight 35000Kg Head 25m
NP SHR 8.5m
3.3.7 Air Pre-Heater:
The purpose of the air pre-heater is to recover heat from the boiler
flue gas which increases the thermal efficiency of the boiler by
reducing the useful heat lost in the flue gas. As a consequence the fuel
gases are also sent to the fuel gas stack (or chimney) at a lower
temperature, allowing simplified design of the ducting and the flue
gas stack. It also allows control over the temperature of gases
leaving the stack.
3.3.8 Economizer:
Flue gases from large boilers are typically 450-650°F. Stack
economizer recover some of this heat for pre-heating water. The
water is most often used for boiler make-up water are some other
need that coincides with boiler operation. Stack economizers should
13
be considered as an efficiency measure when large amounts of make-
up water are used (i.e. not all condensate is return to the boiler or
large amount of live steam are used in the process so there is no
condensate to return) or there is a simultaneous need for large
quantity of hot water for some other use. The savings potential is
based on existing stack temperature, the volume of make-up water
needed and the hours of operation.
3.4 Boiler Protection: Fuel protection
Gas pressure protection
Diesel oil protection
Furnace oil protection
FD fan trip
ID fan trip
Regenerative air pre-heating trip
Drum level high
Drum level low
Re-Heat steam pressure drop
Furnace pressure low
Furnace flame out
Natural gas pressure high
14
4. Steam Turbine Turbine is used to convert the heat energy into mechanical energy.
Turbine used in T.P.S Muzaffar Garh 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.
Steam turbine has three parts.
1. HP turbine
2. IP turbine
3. LP turbine
(To re-heater) (From HP Super-heater) (From re-heater)
Generator
Condenser
15
4.1 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 540 °C and pressure is 130bar.
Outlet steam temperature of the HP turbine is 290°C and pressure is
15bar. HP turbine has total of 12 stages including one is governing
stage.
4.2 IP (Intermediate Pressure) Turbine:
Steam comes into IP turbine from HP turbine via re-heaters. The steam
pressure in this section of turbine is 14bar and temperature is 540°C.
This part has total of 10 pressure stages.
4.3 LP (Low Pressure) Turbine:
The outgoing steam of the IP turbine entered into the LP turbine.
Steam from the LP turbine goes into the condenser.
4.4 Steam Turbine Specification:
Maximum load 210MW Live steam pressure 132bar Live steam temperature 538°C
Rated speed 3000rpm HP cycle exhaust temperature 310°C HP cycle exhaust pressure 24bar Re-Heat steam temperature 538°C Re-Heat steam pressure 14bar
16
4.5 Turbine Protection: Lube oil pressure (low & high)
Vacuum drop
Live steam temperature drop
Axial shift displacement
Gas cooling pump tripping
HP heater level high
All FWP trip high vibration tripping
Trip unit by switch/emergency
5. Furnace Safeguard
Supervisory System (FSSS): The FSSS station consists of the following parts:
Decanting area
Fuel oil tank
First lift pump
Main heater
Second lift pump
Diesel pumps
Recirculation pumps
Recirculation heater
Filters
Control room
5.1 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:
17
o Oil tankers
o 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.
02 pumps are used to fill the main storage tanks from the oil tankers
decanting area. One of them is active (on load) and other is standby.
5.2 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 other tanks 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 20,000𝒎𝟑 hence each
can store 2,00,00,000 litter. There are two diesel oil storage tanks each
having capacity of 1000ton.
5.3 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:
Connection Star Power 55KW
Power factor 0.9
18
Efficiency 90% Voltage 230/400V Speed 2950rpm Current 177/102A
5.4 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 270°C
Pressure 11-13bar
5.5 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 105-120°C.
The specification of second lift pump motor is as:
3 phase 50Hz induction motor:
Power 250KW
Voltage 6.6KV
Speed 2950rpm
Current 252A
19
6. The Generator The generator is a device which converts the mechanical energy into
electrical energy.
6.1 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".
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 commutator which converts the AC into DC. The
following three things are necessary for generation of electrical energy.
Magnetic field
Conductor
Relative motion between conductor and magnetic field
In the small generator the magnetic field is being produced in the stator
and the electromotive force is produced in the rotor through Faraday's law
of electromagnetic induction. The electromagnetic are used in the generator
to produce the magnetic field. 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
20
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
6.2 Main Generator Parameter:
6.2.1 Pilot Exciter:
Type Tfy-46-500 Rated voltage 93/161V Rated current 286/165A
Rated speed 3000rpm Rated power factor 0.875 Phase 3 Rated frequency 50Hz Armature connection ∆/𝒀 Specification OEA.513.039
Manufacturing date 1993-3-1 Rated capacity 46KVA
6.2.2 Alternating Exciter:
Type T1-1165-4 Rated voltage 431V Rated current 1562A
Rated speed 3000rpm Rated power factor 0.91 Phase 3 Rated frequency 100Hz Armature connection 𝒀 Specification OEA.513.039
Manufacturing date 1993-8-24 Rated capacity 1165KVA
21
6.2.3 Turbine Generator Water Hydrogen Cooled:
Type QFSN-210-2 Rated capacity 246MVA Rated output 210MW Rated voltage 15.75KV Rated current 9056A
Rated speed 3000rpm Rated frequency 50Hz Phase 3 Connection of stator winding 2-Y Insulation class F Power factor 0.85
Excitation voltage 289V Excitation current 18.67A Maximum inlet water temperature for stator winding 50°C Maximum inlet cooling hydrogen 50°C Water flow for stator winding 35m2/h Rate H2 pressure 0.3MPa
Specification OEA.512.137 Manufacturing date 1993-2
6.3 Cooling System of Turbo 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 second.
Stator cooling
Rotor cooling
22
6.3.1 Stator Cooling:
The stator of the turbo generator is cooled by distillated or 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 cooling system of the thirstier converts the water is passed through the
hollow conductor of stator winding for its cooling.
The demi water is necessary for the cooling of the stator winding because
raw water is not a pure insulator which may cause the flow of leakage
current when passed through stator winding.
The demi water plant removes the impurities and minerals of the raw
water and make it good insulator whose resistivity is taken at a minimum
level of 200K𝛀.cm. The demi water that process through the stator winding
absorbs the heat of stator winding makes it cool and becomes hot itself.
The demi water then passes through heat exchanger (coolers) where its
temperature is decreased by the circulating water coming from the cooling
towers. This demi water is also passed through the mechanical and
magnetic filters before passing through stator winding and thirstier
converts.
6.3.2 Water Parameters in Heat Exchangers: Rated temperature of cooled water at inlet 32°C
Minimum temperature of cold water 15°C
Number of gas heat exchangers 02
Rated water flow in on heat exchanger 150m3/h 6.3.3 Rotor Cooling:
The rotor cooling is done by H2 gas. Hydrogen is used for the following
purposes:
Its heat exchange capability is much better than other gases.
It is very lighter than other gases so do not overload the rotor.
Its preparation is very easy and cheap.
23
Hydrogen gas is filled in the generator and maintained at a pressure of
4Kg/cm2. It takes all the heat of the rotor and cools the rotor winding and
gets warmed it. For the cooling of the gas there are four gas cooler inside
the generator on each corner. Circulating water of the cooling tower is used
in the gas cooler for hydrogen cooling.
Hydrogen gas is explosive if it is combined with oxygen under pressure so
too avoid any leakage of gas and entrance of air inside the generator the
rotor assembly is sealed by the seal oil whose pressure is at least
0.7Kg/cm2 more than hydrogen gas inside the generator.
When the generator is turned off for a long time for maintenance purpose
hydrogen is released from the generator in the air using special method.
Method involves that firstly fill the generator with CO2 which release the
hydrogen in the air and then in the end air is filled in the generator and
CO2 is released in the air. This method is adopted because if hydrogen is
released using air instead of CO2 then it can cause explosion due to oxygen
in the air which will meet hydrogen under pressure in the generator. After
maintenance hydrogen gas is refilled in the generator using the reverse
process as described above.
6.3.4 Water Parameters in Gas Cooler: Rated temperature of cold water at inlet 32°C
Minimum temperature of cold water 15°C
Maximum water pressure 3Kg/cm2
Number of gas cooler 04
Rated water flow in on gas cooler 76.5m3/h
6.4 Protections of Generator:
The following protections are installed for the protection of the generator
in TPS.
a. Longitudinal Differential Current Protection:
24
This system is intended to protect against multiphase short circuit in
generator stator winding and its leads including against double earth
fault, one of which being the generator.
b. Lateral Differential Current Protection:
This system is intended to protect against turn-to-turn short circuit of one
phase in the generator stator winding.
c. Earth Fault Protection of Stator Winding:
This system is intended to reveal and disconnect one phase earth fault of
generator stator winding.
d. Differential Protection of the Unit:
This system is intended to backup longitudinal differential protection of
generator.
e. Negative Sequence Current Protection:
This system is intended to prevent damage of generator increase of
overloading by negative sequence current caused by asymmetric load or
external asymmetric short circuit and abnormal operating condition of
power grid.
f. Over Current Protection Against Overloading of
Generator:
This system is intended for signaling at symmetric overloading of
generator stator.
g. External Symmetrical Short Circuit Protection:
This system is intended to protect the generator against external
symmetric short circuit.
h. Protection Against Asynchronous mode, when excitation
loss:
25
This system is intended to protect against asynchronous mode. One of the
elements of resistance block relay for protection of the unit against
external symmetrical short circuit used.
i. Protection of Generator Rotor Against Overloading:
This system is intended to protect against overloading under emergency
condition as well as increase of failure of generator excitation system
which cause long term flow of current of abnormal value along the rotor
winding.
j. Earth Fault Protection In One Point of excitation Circuit:
This system is intended to protect the generator incase of earth fault at one
point of excitation circuit.
k. Protection Against Voltage Increase At Generator At Ideal
Operation:
This system is intended to prevent in admissible increase in voltage at
turbo-generator and transformer of unit during ideal operation of the unit
incase of failure of excitation system.
l. Zero Sequence Current Protection:
This system is intended to backup protection at one phase short circuit in
220KV network. It is also used to backup unit protection when short
circuit at the 220KV side of the unit.
m. Differential Protection of the Exciter:
This system is intended to protect against all kind of short circuit in the
exciter winding and on its leads.
n. Over Current Protection of Exciter Against External Short
Circuit:
This system is intended to protect against over current in the external
system of the exciter.
26
7. CYCLES 7.1 Steam Cycle:
27
7.2 Fuel Oil Cycle:
Exhaust
(Chimney) ID Fan Air Pre-
Heater Flue Gases
Furnace
Oil Tanks
Oil
Heaters
Gate & Quick
Closing Valves Burners
(Boiler)
Fuel Oil Cycle
28
7.3 Air Flow Cycle:
Flue Gases Fresh Air
Economizer
G.R.C
Fans
Furnace
A.P.H
Calorifire
ID Fan
FD Fan
Stock
Environment
29
7.4 Condensate Water Cycle:
Dearator
Cond. Storage Tank
Cond. Pump
Makeup Water
DA Pump
Hot well
Condenser
LP
Heater A
LP
Heater B
30
From LP Heater
Dearator
7.5 Feed Water Cycle:
To Economizer
P-8 P-14 BFP C
BFP B
BFP A
Make up water
HP
Heater A
HP
Heater B
31