Detailed History On thermal Power Plant Muzaffarghar

1. INTERNSHIP REPORT
Introduction:-
A power house is a place where power is being produced by any
source, while in thermal power house, electricity is being produced by
steam temperature and pressure. Thermal power station Muzaffargarh is
situated an approximate 2.5 km from Muzaffargarh city.
There are two phases in thermal power station Muzaffargarh
(1,2).There are three units in phase 1 named unit (1,2&3) respectively.
 Phase1 wasmadeby Russia(USSR)butlater modification andexpansion
of plant, unit 4 also introduced in the phase 1 by the co-operation of
Chinese government. Three Russian units have a capacity of 210 MW
each and one Chinese unit of 320 MW each.
 Phase 2 is completely build by Chinese government and have two
units(4&5) respectively. Both units have a capacity of 200 MW each.
Thermal power station:-
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 another
work 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 station 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.
T.P.S. Muzaffar Garh
Installed Capacity:-
This power station is a vital and major thermal power generating
installation connected with national grid system in Pakistan. This power

2. station was constructed in different phases having total capacity of 1350
MW. It has 6 unit(s). The first unit was commissioned in 1993 and the last
in 1995. Itis operated by Pakistan Electric Power Company (PEPCO). These
units made by RUSIA & CHINA.
It consists of:
 Three Russian units of 210 MW each
 Two Chinese units of 200 MW each
 One Chinese unit of 320 MW
Fuel:-
Dualfuel combustion provision (Gas and Furnaceoil) has been made
for all the machines. Furnace oil is transported through Railway Wagons
and Tank Lorries.
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 processes.

3. Hydel power plants convert the potential energy of water to
electrical poweras it flowsfromhigherto lowerelevations. The “traditional
thermal power plant” is the Rankine 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 or steam, is used to convert heat energy to
mechanical energy. The Rankine 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 Rankine cycle has been
refined considerably over the years and made more efficient by the
addition of more components like economizer, feed water heaters, super
heaters and re-heaters. The efficiency of the Rankine cycle has also been
improved by increasing the temperature and pressure of the cycle. The
laws of thermodynamics and considerations such as material limitations
have prevented any significant improvement since then. Power plants
commonly use heat rate to measure the efficiency of the cycle.
Phase-II (Units 5 & 6):-
Itconsists of two units of 210 MW each having equipment similar to
Phase-I. Turbines are placed longitudinally in main building. Outdoor
boilers exhaust of two units is connected to one stack. The power plant is
designed on theblock principle: boiler-turbine-generator-unittransformer.
The steam turbines which drivegenerators are of three stages condensing
type arranged transversely to the axis of turbine hall.
 Fuel & Oil Facilities
Fuel oil facilities are constructed for decanting, oil storage,
preparationand supplyoffuel to boiler nozzles.Italsoincludes HSDstorage
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 inducted draftcooling towers. Thewater is being cooled for each unit

4. in two cooling towers each consisting of eight fans. Two cooling towers
carry 27,500 Cu m/h circulating water for condensers of one unit.
 Startup Boiler
Onestartup boiler using diesel oil as fuelwith 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 30-meter high has
been constructed for it.
 Electrical Part
The electricity generated at 15.75 KV is broughtoutfrom Unit transformer
at 220 KV and fed to the National Grid via a switchyard. Power Plant
auxiliaries are fed at 6.6 KV.

5. CHUCK
There are two main types of chuck used in lathe machine etc.
 3-Jaws chuck
3-Jaws chuck is used for cylindrical or circular workpieces. Itis auto
rotate, means everychuck(fitted at120 ̊ ) moves simultaneously to enclose
the workpiece as shown in the fig.
(3-Jaws Chuck)
 4-Jaws chuck
While in the case of 4-Jaws chuck, every jaw fits at an angle of 90 ̊,
it is not an auto-rotate chuck and every two jaws are fitted separately on
workpiece. 4-Jaws chuck is used for square or rectangular workpieces.
(4-Jaws Chuck)

6. Question: - Can electric current flow through pure water?
Answer: - Mineral water contains salts/minerals. Electric current flows
through mineral/salted water through minerals such as saline water.
While, that water which does not contain minerals is pure water and
electric current cannot flow through pure water due to absence of
minerals. Mineral water is conductor while pure water is insulator even
many hundreds or thousands of kilo volts are applied.
Atmosphericair pressureis 1 ata or 14.7lb/inch2
. The rated speed of
generator is 3000 rpm or 50 cycles per second.
Identification of Fuel Pipe and Steam Pipe:-
The simplest method is to measure the temperature. The pipe with
high temperature indicates that steam is flowing through it while fuel is
flowing in another pipe of low temperature. It is applied when plant is in
running.
Ifthe plant is notin running,then the pipe acrossonwith smallpipes
are attached, indicates, fuel is flowing in this pipe. {REASON} In winter
season, the atmospheric temperature is very low and fuel is freezed in this
pipe at this low atmospheric temperature. To melt this fuel, we use small
pipes of steam acros on the sides of fuel pipe.

7. There is no need to drained out the fuel when justafter the plant is
to be stopped. When the plant is to be stopped just after some time. We
drained out the steam so that when we start the plant again, this steam
will convertinto liquid form up to that time. When we will start our plant,
steam will produce first and then move in steam pipe and also that small
pipes which are attached to fuel pipe so that by steam, this freezed fuel
must come into running position.
Boiler:-
Boiler is an apparatusto producesteam. Thermalenergy released by
combustion of fuel used in boiler is used for many processes in industry. It
is the main partof any thermal powerplant. Itconvertsthefuel energyinto
steam energy. Itgenerates steam, so it may be named as steam generator.
If boiler/steam generator produces stream of 1-300 psi, then it is called as
boiler. If it produces steam of greater than 300 psi, it is termed as steam
generator.
 The type of boiler used in the TPS phase-II is ‘’water tube boiler’’.
Types of Boiler:-
It has many types based upon different parameters. There are two
main types of boiler (according to what flows in the tube).
1. Water-tube boiler:-
In water tube boilers, boiler water passes through thetubes while the
exhaust gases remain in the shell side passing over the tube surfaces.
Water-tube boilers are used where high steam pressure(as high as 3000
psi) is required because tubes can withstand high internal pressurethan in
the chamber shell. These are capable of high efficiencies and can generate
saturated or superheated steam with high pressure and high energy.
Water-tube boiler has useful practical applications than fire-tube boiler.

8. MERITS OF WATER TUBE BOILERS OVERFIRE TUBE BOILERS:-
1. Generation of steamis much quicker due to small ratio of water content
to steam content. This also helps in reaching the steaming temperature in
short time.
2. Its evaporative capacity is considerably larger and the steam pressure
range is also high-200 bar.
3. Heating surfacesaremoreeffective asthe hotgasestravel atright angles
to the direction of water flow.
4. The combustion efficiency is higher because complete combustion of
fuel is possible as the combustion space is much larger.
5. The thermal stresses in the boiler parts are less as different parts of the
boiler remain at uniform temperature due to quick circulation of water.
6. Theboiler can be easily transportedand erected as its different partscan
be separated.
7. Damage due to the bursting of water tube is less serious. Therefore,
water tube boilers are sometimes called safety boilers.

9. 8. All parts of the water tube boilers are easily accessible for cleaning,
inspecting and repairing.
9. The water tube boiler's furnace area can be easily altered to meet the
fuel requirements.
Demerits:-
1. It is less suitable for impure and sedimentary water, as a small deposit
of scale may causethe overheating and bursting of tube. Therefore, useof
pure feed water is essential.
2. They require careful attention. The maintenance costs are higher.
3. Failure in feed water supply even for short period is liable to make the
boiler over-heated.
2. Fire-tube boiler:-
In the case of fire-tube boiler, exhaust gases/fire passes through the
tubes while water remains in the shell side passing over the surfaces.
Advantages of fire tube boilers are as follows:-
1. Low cost
2. Fluctuations of steam demand can be met easily
3. It is compact in size.

10. Boiler properties:-
(i) Safety. The boiler should be safe under operating conditions.
(ii) Accessibility. The various parts of the boiler should be accessible for
repair and maintenance.
(iii) Capacity. Should be capable of supplying steam according to the
requirements.
(iv) Efficiency. Should be able to absorb a maximum amount of heat
produced due to burning of fuel in the furnace.
(v) Construction. It should be simple in construction.
(vi) Low cost. Its initial cost and maintenance cost should be low.
(vii) No Joints. The boiler should have no joints exposed to flames.
(viii)Quick starting. It should be capable of quick starting and loading.
Boiler performance:-
Evaporative capacity can be expressed in terms of:
a) kg of steam/hr
b) kg of hour/hr/m2
of heating surface
c) kg of steam/kg of fuel fired
𝑩𝒐𝒊𝒍𝒆𝒓 𝒆𝒇𝒇𝒊𝒄𝒊𝒆𝒏𝒄𝒚 = 𝟏 −
𝑻 𝟐
𝑻 𝟏
Here,
T1 is Inlet temperature
T2 is outlet temperature
Turbine:-
A turbine is a rotaryengine thatextracts energyfrom a fluid flow and
converts it into usefulwork. Thesimplestturbines have one moving part, a
rotor assembly, which is a shaft with blades attached. Moving fluid acts on
the blades, or the blades react to the flow, so that they rotate and impart
energy to the rotor. Early turbine examples are windmills and water
wheels.Itsmodern manifestationwasinvented SirCharles Parsonsin1884.
A windmill is the simplest kind of turbine.

11. (Turbine)
Impulse and Reaction Turbines:-
Turbines work in two different ways described as impulse and
reaction.
Impulse turbines:-
A Pelton water wheel is an example of an impulse turbine. Itspins as
oneor morehigh-pressurewaterjetsfireinto the bucketsaroundthe edge.
This one was originally used in a power plant. An impulse turbine like this
works when the incoming fluid hits the buckets and bounces back again.

12. The exact shape of the buckets and how the fluid hits them makes a
big difference to how much energy the turbine can capture.
In an impulse turbine, a fast-moving fluid is fired through a narrow
nozzle at the turbine blades to make them spin around. The blades of an
impulse turbine are usually bucket-shaped so they catch the fluid and
direct it off at an angle or sometimes even back the way it came (because
that gives the most efficient transfer of energy from the fluid to the
turbine). In an impulse turbine, the fluid is forced to hit the turbine at high
speed.
Water turbines are often based around an impulse turbine (though
some do work using reaction turbines). They're simple in design, easy to
build, and cheap to maintain, not least because they don't need to be
contained inside a pipe or housing (unlike reaction turbines).
Reaction Turbine:-
Water or steam flows past the angled blades, pushing them around
and turning the central shaft to which they're attached. The shaft spins a
generator that makes electricity. A reaction turbine like this is much more
like a propeller. The main difference is that there are more vanes in a
turbine.
In a reaction turbine, the blades sit in a much larger volume of fluid
and turn around as the fluid flows past them. A reaction turbine doesn't
change the direction of the fluid flow as drastically as an impulse turbine:

13. it simply spins as the fluid pushes through and past its blades. Wind
turbines are perhaps the most familiar examples of reaction turbines.
Steam Turbine:-
A Steam Turbineis a mechanical device that extracts thermalenergy
frompressurized steam, and converts itinto usefulmechanicalwork. Ithas
replaced the reciprocating piston steam engine because of its greater
thermal efficiency and higher power-to-weight ratio. Because the turbine
generates rotary motion, it is particularly suited to be used to move
electrical generator.
As its name suggests, a steam turbine is powered by the energy in
hot, gaseous steam—and works like a cross between a wind turbine and a
water turbine. Like a wind turbine, it has spinning blades that turn when
steam blows past them; like a water turbine, the blades fit snugly inside a
sealed outer container so the steam is constrainedand forcedpastthem at
speed.
Steam turbines use high-pressure steam to turn electricity
generatorsatincredibly high speeds,sothey rotatemuch fasterthan either
wind or water turbines. (A typical power plant steam turbine rotates at
1800–3600 rpm—about 100–200 times faster than the blades spin on a
typical wind turbine, which needs to use a gearbox to drive a generator
quickly enough to make electricity.)

14. Just like in a steam engine, the steam expands and cools as it flows
past a steam turbine's blades, giving up as much as possibleof the energy
it originally contained. But, unlike in a steam engine, the flow of the steam
turns the blades continually: there's no push-pull action or waiting for a
piston to return to position in the cylinder because steam is pushing the
blades around all the time. A steam turbine is also much more compact
than a steam engine: spinning blades allow steam to expand and drive a
machinein a much smaller spacethan a piston-cylinder-crankarrangement
would need. That's one reason why steam turbines were quickly adopted
for powering ships, where space was very limited.
If the load is suddenly increased, rpm increased, frequency also
increased. To maintain this frequency, we decrease the steam flow which
decreases the speed and maintain the frequency. If the load is suddenly
decreased, rpm decreased, frequency also decreased. To maintain this
frequency, we increase the steam flow which increases the speed and
maintain the frequency.Therearemanytypesof steam turbinebasedupon
different parameters.
Types of turbine based upon steam pressure:-
1. Low pressure (L.P) turbine
2. Medium pressure (I.P) turbine
3. High pressure (H.P) turbine

15. Question: How we identify which is H.P turbine or L.P turbine
Answer: The turbine whoserotor blade diameter is small. Steam flows in
the small diameter rotor blade produces high pressure steam, named as
high pressure turbine, while, the turbine whose rotor blade diameter is
large. Steam flows in the large diameter rotor bladeproduces low pressure
steam, named as low pressure turbine.
There arethree high pressureturbines in TPS phase-II. High pressure
turbine# 1 has less temperature than other both high pressure turbines.
High pressure turbine# 2 has small less temperature than high pressure
turbine# 3 but greater than that of high pressure turbine#1
Boiler produces steam. This steam enters into Derheater whereflue
gases from steam is extracted. Then in the boiler drum, downcomer and
uprise is occurred. Then steam comes into the H.P turbine. Then steam
comes into the I.P turbine from H.P turbine via reheaters. Then steam
comes into the L.P turbine from I.P turbine.
Air Preheater:-
An air preheater (APH) is a general term used to describe any device
designed to heat air before another process (for example, combustion in a
boiler) with the primary objective of increasing the thermal efficiency of
the process. They may be used alone or to replace a recuperative heat
system or to replace a steam coil.

16. In particular, this article describes the combustion air preheaters
used in large boilers found in thermal power stations producing electric
power from e.g. fossil fuels, biomass or waste.
The purpose of the air preheater is to recover the 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 flue
gases are also conveyed to the flue gas stack (or chimney) at a lower
temperature, allowing simplified design of the conveyancesystem and the
flue gas stack. It also allows control over the temperature of gases leaving
the stack (to meet emissions regulations, for example)
Itrecovers the heat of flue gases coming from economizer. Itis used
to preheat the air before entering the furnace. Air preheater may be of
three types: -
1. Plate type
2. Tubular type
3. Regenerative type
Economizer
Economizer is a mechanical device which is used to capture the
waste heat from boiler stack gases (flue gas) and transfer it to the boiler
feedwater. This raises the temperature of the boiler feedwater, lowering
the needed energy input, in turn reducing the firing rates needed for the
rated boiler output.
A common application of economizers in steam power plants is to
capture the wasteheat from boiler stack gases (flue gas) and transfer it to
the boiler feedwater. This raises the temperature of the boiler feedwater,
lowering the needed energy input, in turn reducing the firing rates needed
for the rated boiler output.
The function of the economizer is as its name implies, to
“economize” or saveon cooling costs.Obviously,it costsmoney to operate
the compressor. If the compressor can be shut down and the system still
provide adequate cooling, energy savings can be realized.
Heat internal to the building such as people, lights, computers, copy
machines, motors and other machines causes the temperature inside a
structure to increase. Heat soaked up by the building structure may also
continue to heat the building long after the temperature outside the

17. building has dropped. There are times when the temperature outside a
building is lower than the temperature inside.
Whenever the cooling system is calling for cooling and the
temperature outside is cool enough it is economical to shut off the
compressor and bring in cool outsideair to satisfy the cooling needs of the
building. Such is the function of an air economizer system.
There is one drawback to this type of control system. Even though
the thermostat acknowledges that the outside air temperature is low
enough to cool the building, the outside air may be too humid to provide
adequate comfort for the building occupants. The occupants will feel cool
but clammy. The solution is an economizer that adds a second control
which works in harmony with the outdoor thermostat and measures the
outdoor air humidity. Such a control is called an “enthalpy” control. The
term “enthalpy” means, total heat. The enthalpy control measures both
sensibleand latent heat in the air and only allows outsideair to be used for
cooling if the air is both cool anddry enoughto satisfythespaceconditions.
Ifthe indoor thermostatcalls forcooling and the outside air enthalpy (total
heat) is low enough then the economizer brings in this cooler and less
humid air and usesit forcooling instead of operating thecompressor.Using
the outsideair for cooling is less expensive than operating the compressor
to providecooling. So an enthalpy control is a control which checks to see
if both the temperature (sensible heat) and the humidity (latent heat) are

18. low enough to be used for cooling. This combination provides for the
greatest comfort at the least cost.
Not all economizers use enthalpy controls. Some just check the
outside air temperature and do not check the outside air humidity. Those
controls do not providethe same levels of comfortas enthalpy controlled
economizers. Economizers can save a great deal of energy.
They can also waste energy if they aren not operating properly or
are improperly adjusted. For example, if the outside air dampers are not
closing properly when the outside air temperature is high, then hot air is
unnecessarily entering the building and causing the air conditioning
compressor to operate longer and under higher loads thus consuming a
great deal more energy than necessary.
cost of one or two months of energy wasted.
Many economizers are not functioning at all or are out of service
because they are not well understood by some service technicians. Many
service technicians simply disable them. It is essential that economizers
are working properly and saving energy rather than increasing costs.
Air economizers are available for residential and commercial
systems and can be retrofitted to most systems as energy conserving
devices. Most packaged light commercial systems (rooftop systems) have
an economizer add-on package as an option which can be installed when
the system is new or may added to the system later.
Economizer Maintenance:-
The following items should be checked at least annually to ensure
the air economizer is operating properly:
• Setting & operation of the outdoor thermostat or enthalpy control.
• Condition of the outdoor thermostat or enthalpy control.
• Proper setting and operation of the economizer mixed air thermostat.
• Proper damper operation and lubrication.
 Minimum damper position adjustment.
• Correct operation of the system when a call for cooling comes from the
 thermostat.
• Function and condition of the economizer damper motor.
• Condition of the wiring and electrical terminations.

19. Since the enthalpy controlis located in the outdoor air air-stream and is
a relatively sensitivecontrol, it is not uncommonto haveto replaceit every
few years depending upon the location of the equipment and the weather
extremes in the area. Thecostofa replacementcontrolis usuallyrecovered
quickly through the energy saved. Economizer service should be a part of
the scheduledmaintenance performedat leaston a yearly basis.Justasour
automobiles need regular serviceso do residential and commercialheating
& cooling systems. Like automobiles, the frequency of service depends
upon howit is operated, how often & long it operatesand the environment
where it operates.