Nahar Project Report Harry58

7/27/2019 Nahar Project Report Harry58

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MECHANICAL ENGINEERING DEPARTMENT

SHAHEED UDHAM SINGH COLLEGE OF ENGINEERING &

TECHNOLOGY, TANGORI

SIX MONTHS INDUSTRIAL TRAINING

AT

NAHAR INDUSTRIAL ENTERPRISES LTD.

SUBMITTED TO

PUNJAB TECHNICAL UNIVERSITY, JALANDHAR

IN THE PARTIAL FULFILLMENT OF THE REQUIREMENTS

FOR THE AWARD OF THE DEGREE OF BACHELORS OF

TECHNOLOGY IN

MECHANICAL ENGINEERING

FACULTY CO-ORDINATOR:

SUBMITTED BY:

ER.ROHIT RAMPAL

HARPREET SINGH


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BRANCH-ME/2009 BATCH

R

OLL NO- 90691163358

INTRODUCTION:

NAHAR is a subsidiary of Nahar group and was establish in

1983.The company is involved both, in manufacture and exportof cotton and woolen products.NAHAR SPINNING MILLS is a

subsidiary of Nahar group and was establish in 1983.The

company is involved both, in manufacture and export of cotton

and woolen products. Nahar Industrial Enterprises Ltd is a

vertically-integrated textile manufacturer, with operations

ranging from spinning, weaving & processing to finished

readymade garments. NIELs strategic objective is to capitalize

on the growth opportunities that it believes are availed in thedomestic and global textile industry .at the same time the

company recognizes the competitive nature of the industry,

especially with established pressure from Asia, and that to

maintain growth it must continue to improve production

process and reduce cost.

From 1949 when small hosiery factory was incorporated into a

public limited company, to the present day, constants upwardgrowth has symbolized the charter of a company called oswal

woolen mills limited.Oswald woolen mills , established in 1949

surges ahead to establish itself as a reputed industrial

conglomerate with a wide ranging portfolio from wool combing ,

spinning, kitting , fabric, hosiery garments etc.From starting out

with 800spindles today, from simple hosiery items to high value

added items like designer knitwear (Monte Carlo

&Canterbury) all these are no mean achievements and what


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made them possible in so short a time is nothing but a miracle

that combined brilliant market insight with diversification.

As the company progressively increased spindlier to 2000 in

the year 1960, it had already established a market for itself inthe areas of hosiery knitwear & textile fabrics like blankets and

shawls etc.

Very soon , it becomes the Indian exporter of woolen garments

to Russia and shortly after in 1972, the company set up its own

wool combing unit the first of several backward integration

measures .Soon began the in house processing for the woolen

division .With increasing capacity 7b demand for its processing

for the woolen division.With increasing capacity & demand for

its products, oswal woolen mills limits soon became a name e

to reckon with, both in the domestic & international markets

Research & developments also received focused attention &

international market. Research & developments also received

focused attention & today the company boats of north Indias

most sophisticated laboratory, approved by the international

wool secretariat (iws) & is even authorized to act as a quality

checking center for other manufacturers.

For the domestic market the company launched Monte Carlo,

the first truly international range of designer knitwear followed

b another prestigious brand Canterbury

Later on an ultra modern lambs wool & angora spinning plant

has been set up, of which more than 50% manufacturer is for

captive consumption .The balance meets the requirements ofother hosiery knitwear exporters in India. This in turn means

immense saving in foreign exchange for India.


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PROJECT REPORT

PROJECT : TO STUDY THE WORKING OF STEAM

POWER PLANT

Introduction

A steam power plant converts the energy of the fossil fuel (coal,

oil, gas) into mechanical/electrical energy. This is achieved by

raising the steam, in the boilers, expanding it through the

turbines and coupling the turbines to the generators which

convert mechanical energy to electrical energy as shown in fig.

Electrical Energy

Generator

Waste gases

Water

Fuel

Boil

er

T

u

r

b

i

n

e

~ Grid system


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Fig.1

Production of electrical energy by steam power plantThe following two purposes can be served by a steam power

plant.

To produce electric power.

To produce steam for industrial purposes besides producing

electric Power. The steam may be used for varying purposes in the

industries such as textiles, food manufacturer, paper mills,

sugar mills and refineries etc.


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Components of modern steam power plant

A modern steam power plant comprises of the following components:

1. Boiler

a. Super heater

b. Re-heater

c. Economizer

d. Air pre-heater

2. Steam turbine

3. Generator

4. Condenser

5. Cooling tower

6. Circulating water pump

7. Boiler feed pump

8.Wagon tippler

9. Crusher house


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10. Coal mill

11. Induced draft fan

12. Ash precipitators

13. Boiler chimney

14. Forced draught fans

15. Water treatment plant

16. Control room

17. Switch yard.

Essential requirements of steam power station design

The essential requirements of steam power station design are:-

1. Reliability

2. Minimum capital cost3. Minimum operating and maintenance cost

4. Capacity to meet peak load effectively

5. Minimum losses of energy in transmission

6. Low cost of energy supplied to the consumers

7. Reserve capacity to meet future demands.


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Layout of a modern steam power plant

The layout of modern steam power plant comprises of the

following four circuits:

Coal and ash circuit

Air and gas circuit.

Feed water and steam flow circuit.

Cooling water circuit

To chimney

Flue gases

Air

Air Flue gases

Feed water

Main valve

Flue Superheated

gases steam Exhaust steam

Steam BFP HP heater

CE pump

Coal

storage

Super

heaterBoil

erAsh

storage

Coal

handlin

lant

Ash

handlin

lant

Economis

Air

prehea

Generato

Condens

T

u

r

b

i

ne~


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Feed water and steam flow circuit

In the water and steam circuit condensate leaving the condenser is first heated in

a closed feed water heater through extracted steam from the lowest pressure

extraction point of the turbine. It then passes through the deaerator and a few

more water heaters before going into the boiler through economizer.

In the boiler drum and tubes eater circulates due to the difference between the

density of water in the lower temperature and the higher temperature section of

the boiler. Wet steam from the drum is further heated up in the super heater

before being supplied to the prime mover. After expanding in high pressure

turbine steam is taken to the reheat boiler and brought to its original dryness or

superheat before being passed on to the low pressure turbine. From there it is

exhausted through the condenser into the got well. The condensate is heated on

the feed heaters using the steam trapped from different points of turbine.A part of steam and water is lost while passing through different components

and this is compensated by supplying additional feed water. This feed water

should be purified before hand, to avoid the scaling of the tubes of the boiler.

Cooling water circuit


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The cooling water supply to the condenser helps in maintaining a low pressure

in it. The water may be taken from a natural source such as River, Lake or sea

or the same water may be cooled and circulated over again. In the later case the

cooling arrangement is made through spray pond or cooling tower.

Design basis of steam power plant

Contents

Rice husk, Indian

coal, and Barmer

ligniteNet steaming capacity at MCR for bagasse firing.

Steam pressure at main steam stop valve.

Steam temperature at super heater outlet.

Steam temperature control range.

Boiler design pressure.

Feed water temperature at de-aerator outlet and

economizer inlet.

De-aerator operating pressure.

De-aerator design pressure.

De-aerator operating temperature.

De-aerator design temperature.

Dissolved oxygen in the outlet water (max).

Dissolved maximum dust contents in the flue gas leaving

Kg/hr

Kg/cm(g)

C

%

Kg/cm(g)

C

Kg/cm(a)

Kg/cm(a)

C

C

ppm

mg/Nm

55000

86

5155

60-100

103

170

1.75

3.5

115

150

0.001

115


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the dust collection system.

Heat losses and thermal efficiency (%)

Fuel name Rice husk Indian

coal

Barmer

coal

Woodchips+

rice husk

Losses:

Un-burnt carbon.

Dry gas.

Fuel moisture.

Air moisture.

Radiation.

Hydrogen moisture.

Unaccounted.

Total losses.

Manufacture margin.

Boiler thermal

efficiency.

4

4.42

2

0.14

0.45

5.37

0.4

16.78

0.72

82.5

4

4.28

1.57

0.14

0.45

3.37

0.5

14.31

0.68

85

3

5.04

4.05

0.17

0.45

5.21

0.5

18.42

0.58

81

4

5.19

2.83

0.17

0.45

6.49

0.4

19.53

0.47


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Gas temperature profile (C)

Primary SH I/L.

Primary SH O/L.

Economizer I/L.

Economizer

O/L.

Air pre-heater

I/L.

Air pre-heater

O/L.

792

511

507

236

236

140

801

500

499

229

229

140

810

523

513

238

238

140

794

522

512

240

240

140

Steam temperature profile (C)

Primary SH I/L.

Primary SH O/L.

Secondary SH

I/L.

Secondary SH

317

468

453

515

317

461

446

515

317

473

452

515

317

472

453

515


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economizer.

Average steam velocity in

primary/secondary super-heater.

Average steam velocity in bed

super-heater.

44

Flow data (kg/hr)

Fuel name Rice

husk

Indian

coal

Barmer

lignite

Wood chips

(60 %) + rice

husk (40%)

Steam flow at MS line at

MCR.Attemperator spray water

flow.

Flue gas flow rate.

Fuel flow rate.

Combustion air flow.

55000

85080847

13742

69793

55000

85074349

11108

67981

55000

115080608

11574

72167

55000

110083802

12715

72770

Heat transfer area (IBR)

Drums.

Furnace front wall.

Furnace side wall.

N.A

123

426


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WORKING:

The 12.0 MW cogeneration power plants are located adjacent to the

proposed Denim plant in the new site, around 1.5 km back side of the

existing textile mill complex.

Under the present arrangement, the total power requirement of the textile

plant complex is being met by the existing 5.0 MW cogeneration plant in

addition to the available diesel generator set in the factory and from PSEB

grid, the total process steam requirement of around 25 TPH at 9 atm,

280C level for the existing textile plant in being met existing one no. of 40

TPH AFBC boiler and small capacity of fired boilers as stand by boilers,

after installation of the proposed cogeneration program, the total power for

the entitle textile mill complex will be met from the proposal one no. new

12.0 MW extraction cum condensing turbo generator set, one no. existing

5.0 MW extraction cum condensing turbo generator set and one no. 4.0

MW existing DG set. The process steam requirement of the existing textile

units will be met from the existing boilers and the process steam

requirement of around 12 TPH at 9 atm. Level for the proposed new

expansion of plant will be met from the proposed new 55 TPH AFBC

boiler and the new 12.0 MW condensing cum extraction turbine.


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As the new 12.0 MW cogeneration plant is planed adjacent to the proposed

denim mill plant, the power from the 12.0 MW cogeneration plant will be

fed to the existing common NIEL substation on the textile complex and

distributed to NIEL the entire textile mill complex from the substation.

The management has decided to go in boiler and turbo generator in the

proposed cogeneration plant. The co-generation program envisages a new

AFBC boiler and a single extraction single bleed cum condensing turbo

generator. Having considered the present co generation technology level,

both in India and abroad, the management has decided to adopt 87 atm and

515C cycles for the cogeneration project at their proposed co-generation

plant.

The plant and equipment for the co-generation program will consist of a

high pressure boiler, extraction cum condensing turbo generator, cooling

water system, water treatment system, condensate system, compressed air

system and electrical system consisting of switchgears, LT distribution

panels, transformer for meeting the in house power requirement, etc.

The power plant cycle will we provided with a deaerator serving the dual

purpose of deaerating the feed water as well as heating the feed water with

the extraction steam drawn through the uncontrolled extraction. The

deaerator will be operating at 3.0 atm, with a deaerated feed water

temperature at 115C. The feed water will be further heated to improve the

cycle efficiency in the HP heater that will be operating with the 9 atm

extraction steam and the condensate of the heating steam from the feed

water heater will be taken to the deaerator.


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The power generation in the cogeneration plant will be at 11 KV level. The

internal consumption requirement will be meeting by steeping down the

voltage level to 415 Volts.

Under the present arrangement, the total power requirement of the textile

plant complex is being meet by the existing 5.0 MW cogeneration plant in

addition to the available diesel Generator set in the factory and from PSEB

grid. After the cogeneration program, the entire power requirement for the

entire textile mill complex will be distributed from the existing common

substation available in the textile mill complex by operating the new 12

MW cogeneration turbo generator, existing 5MW cogeneration turbo

generator and 4 MV D.G set. Only the process steam requirement of

around 12.5 TPH at 9 atm level for the proposed new denim plant will be

meet from the 12 MW cogeneration and turbo generator.

The water requirement of the cogeneration plant is proposed to be meeting

from the bore wells proposed in the new cogeneration plant site. The

factory expects that there will not be any difficulty in meeting with the

water requirement of the cogeneration plant.

The proposed cogeneration plant will be working for a minimum of 330

days for a year, with rice husk as the main fuel and other biomass fuels as

standby fuels. However, provision will be made in the cogeneration plant

for firing other fuels like Indian coal and Barmer lignite.


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All steam calculations are done based on the plant operation of 24 hours

for a minimum of 330 days in a year.

The total process steam requirement for the plant is taken as 24.24 TPH

including the heating steam required for the deaerator and HP heater with

the following breakup.

1. Process requirement 12.5 TPH

2. Deaerator steam requirement 4.58 TPH

3. HP heater 6.06 TPH

4. Ejector and gland sealing requirement 1.1 TPH

The process steam requirement at the consumption points for the proposed

denim mill is consider as 8 atm at process plant inlet terminal point and for

deaeration is 3.0 atm. Accordingly the turbine extraction pressure is

selected as 9 atm at terminal point. The process requirement and for the

requirement of ejector and gland sealing system and HP heater of boiler.

The exhaust steam from the turbine will be condensed in the condenser and

used as the boiler feed water.

The boiler being proposed for the cogeneration plant shall be with the

steam parameter of 87 atm and 515C at the boiler outlet. The boiler

proposed is of modern design with membrane furnace wall, atmospheric

fluidized boiler suitable for outdoor installation with electrostatic

precipitators for dust collection. The boiler will have facility to have

uninterrupted flow of rice husk and other biomass fuels enabled by twin


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bunker system located in the side of the boiler. The new boiler and

cogeneration ill have DCS based control system for operation.

Fuel will be stored in the storage yard and feed into the boiler bunker

system through conveyors. There will be a ash handling system to handled

all the ash generated in the boiler in dry form and transported to the nearby

area in own specified land for land filling in low lying area and will also be

tried for the other industries for using the same in cement manufacturing

brices manufacturing of possible. The ash handling system will be insured

that the denim plant near and clean. The proposed boiler will have the

electrostatic precipitator as the dust collection system for reducing the

outlet flue gases dust concentration level of 115 mg/Nm.

The proposed boiler will operate with balance draft conditions with the

help of forced and induced draft fans. There will be deaerator which

deaerates the feed water and supply the feed water to the feed water pumps

at about 115C and this feed water will be further heated in the high

pressure HP heater to improve the cycle efficiency.

With the outlet steam parameters of the boiler at 87kgf/cm and 515C the

main steam line from the boiler is connected to the turbo generator and

supply steam to the pressure reducing and de-superheating station.

The cogeneration steam envisages extraction cum condensing turbo

generator of 12 MW nominal capacities, operating with the steam inlet


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parameters of 84 atm and 510C. The turbo generator will be installed with

all necessary auxiliary plants and system required for efficient operation of

co-generation plant.

The steam turbo generator will generate power at 11 KV. The quantum

power required for meeting the entire NIEL textile mills complex

requirement as well as the co-generation plant in house requirement meet

by the new turbo generator in addition to the existing TG, DG sets and

PSEB power and stand by for NIEL.

The plant and equipments for the co-generation plant will consist of the

following auxiliary equipments.

There will be raw storage water tank and from the raw water storage tank

the raw water will be pumped to the water treatment plant through

centrifugal pumps.

The water treatment plant will treat the raw water to the required quality

level of boiler feed water.

There will be a three cell cooling tower which pumps for condensing the

exhaust steam from the turbine. The condensate will be circulated to the

boiler as feed water through the condensate extraction pumps and

deaerator.


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Boiler

A boiler is a closed vessel in which water or other fluid is heated under

pressure. The fluid is then circulated out of the boiler for use in various

processes or heating applications.

Construction of boilers is mainly limited to copper, steel, stainless steel, and

cast iron. In live steam toys,brass is often used.

The source of heat for a boiler is combustion of any of several fuels, such as

wood, coal, oil, ornatural gas. Electric boilers use resistance orimmersion type

heating elements. Nuclear fission is also used as a heat source for generating

steam. Heat recovery steam generators (HRSGs) use the heat rejected from

other processes such as gas turbines

Boiler fitting and Mountings

1. Safety valves

An important boiler fitting is the safety valve. Its function is to protect the boiler

shell from over pressure and subsequent explosion.

Many different types of safety valves are fitted to steam boiler plant, but they

must all meet the following criteria:
http://en.wikipedia.org/wiki/Pressure_vesselhttp://en.wikipedia.org/wiki/Waterhttp://en.wikipedia.org/wiki/Fluidhttp://en.wikipedia.org/wiki/Pressurehttp://en.wikipedia.org/wiki/Copperhttp://en.wikipedia.org/wiki/Steelhttp://en.wikipedia.org/wiki/Stainless_steelhttp://en.wikipedia.org/wiki/Cast_ironhttp://en.wikipedia.org/wiki/Live_steamhttp://en.wikipedia.org/wiki/Brasshttp://en.wikipedia.org/wiki/Combustionhttp://en.wikipedia.org/wiki/Fuelhttp://en.wikipedia.org/wiki/Woodhttp://en.wikipedia.org/wiki/Coalhttp://en.wikipedia.org/wiki/Petroleumhttp://en.wikipedia.org/wiki/Natural_gashttp://en.wikipedia.org/wiki/Electrical_resistancehttp://en.wikipedia.org/w/index.php?title=Immersion_boiler&action=edithttp://en.wikipedia.org/wiki/Nuclear_fissionhttp://en.wikipedia.org/wiki/Steamhttp://en.wikipedia.org/wiki/Heat_recovery_steam_generatorhttp://en.wikipedia.org/wiki/Gas_turbinehttp://en.wikipedia.org/wiki/Waterhttp://en.wikipedia.org/wiki/Fluidhttp://en.wikipedia.org/wiki/Pressurehttp://en.wikipedia.org/wiki/Copperhttp://en.wikipedia.org/wiki/Steelhttp://en.wikipedia.org/wiki/Stainless_steelhttp://en.wikipedia.org/wiki/Cast_ironhttp://en.wikipedia.org/wiki/Live_steamhttp://en.wikipedia.org/wiki/Brasshttp://en.wikipedia.org/wiki/Combustionhttp://en.wikipedia.org/wiki/Fuelhttp://en.wikipedia.org/wiki/Woodhttp://en.wikipedia.org/wiki/Coalhttp://en.wikipedia.org/wiki/Petroleumhttp://en.wikipedia.org/wiki/Natural_gashttp://en.wikipedia.org/wiki/Electrical_resistancehttp://en.wikipedia.org/w/index.php?title=Immersion_boiler&action=edithttp://en.wikipedia.org/wiki/Nuclear_fissionhttp://en.wikipedia.org/wiki/Steamhttp://en.wikipedia.org/wiki/Heat_recovery_steam_generatorhttp://en.wikipedia.org/wiki/Gas_turbinehttp://en.wikipedia.org/wiki/Pressure_vessel


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The total discharge capacity of the safety valve(s) must be at least equal to the

'from and at 100C' capacity of the boiler. If the 'from and at' evaporation is

used to size the safety valve, the safety valve capacity will always be higher

than the actual maximum evaporative boiler capacity.

2. Boiler stop valves

A steam boiler must be fitted with a stop valve (also known as a crown valve)

which isolates the steam boiler and its pressure from the process or plant. It is

generally an angle pattern globe valve of the screw-down variety. Figure shows

a typical stop valve of this type.

Fig.4

In the past, these valves have often been manufactured from cast iron, with steel

and bronze being used for higher pressure applications. The stop valve is not


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designed as a throttling valve, and should be fully open or closed. It should

always be opened slowly to prevent any sudden rise in downstream pressure and

associated waterhammer, and to help restrict the fall in boiler pressure and any

possibleassociated_priming.

3. Feedwater check valves

The feedwater check valve is installed in the boiler feedwater line between the

feedpump and boiler. A boiler feed stop valve is fitted at the boiler shell.

The check valve includes a spring equivalent to the head of water in the

elevated feedtank when there is no pressure in the boiler. This prevents the

boiler being flooded by the static head from the boiler feedtank.

Fig.5


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4. Boiler check valve

Under normal steaming conditions the check valve operates in a conventional

manner to stop return flow from the boiler entering the feedline when the

feedpump is not running. When the feedpump is running, its pressure

overcomes the spring to feed the boiler as normal. Because a good seal is

required, and the temperatures involved are relatively low (usually less than

100C) a check valve with a EPDM (Ethylene Propylene) soft seat is generally

the best option.


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Fig.7

9. Gauge glasses and fittings

All steam boilers are fitted with at least one water level indicator, but those with

a rating of 100 kW or more should be fitted with two indicators. The indicators

are usually referred to as gauge glasses complying with BS 3463.

A gauge glass shows the current level of water in the boiler, regardless of the

boiler's operating conditions. Gauge glasses should be installed so that their

lowest reading will show the water level at 50 mm above the point where

overheating will occur. They should also be fitted with a protector around them,

but this should not hinder visibility of the water level.

Gauge glasses are prone to damage from a number of sources, such as corrosion

from the chemicals in boiler water, and erosion during blow down, particularly


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at the steam end. Any sign of corrosion or erosion indicates that a new glass is

required. When testing the gauge glass steam connection, the water cock should

be closed. When testing the gauge glass water connections, the steam cock pipe

should be closed

10. Air vents and vacuum breakers

When a boiler is started from cold, the steam space is full of air. This air has no

heat value, and will adversely affect steam plant performance due to its effect of

blanketing heat exchange surfaces. The air can also give rise to corrosion in the

condensate system, if not removed adequately. The air may be purged from the

steam space using a simple cock; normally this would be left open until a

pressure of about 0.5 bar is showing on the pressure gauge. An alternative to the

cock is a balanced pressure air vent which not only relieves the boiler operator

of the task of manually purging air (and hence ensures that it is actually done), it

is also much more accurate and will vent gases which may accumulate in the

boiler. Typical air vents are shown in Figure When a boiler is taken off-line, the

steam in the steam space condenses and leaves a vacuum. This vacuum causes


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reached in the steam space, the vacuum breaker opens to allow condensate to

drain down to the steam trap.

Fig.9

In general, it is not desirable to introduce air into the steam space, since it acts

as a barrier to heat transfer and reduces the effective steam temperature . This

becomes a problem on larger heat exchangers, where it is not advisable to use a

vacuum breaker to overcome stall. Furthermore, if the condensate is lifted after

the steam trap, for example, into a raised condensate return main, the vacuum

breaker cannot assist drainage. In both these cases, it is necessary to use an

active method of condensate removal such as a pump-trap

Separators

'Wet' steam is a major concern in a steam system as it can cause process and

maintenance problems, including lower productivity, erosion and corrosion.


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Fig.10

Deaerator

Oxygen is the main cause of corrosion in hotwell tanks, feedlines, feedpumps

and boilers. If carbon dioxide is also present then the pH will be low, the water

will tend to be acidic, and the rate of corrosion will be increased. Typically the

corrosion is of the pitting type where, although the metal loss may not be great,

deep penetration andperforation can occur in a short period.


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of steam. This gives a high surface area to mass ratio and allows rapid heat

transfer from the steam to the water, which quickly attains steam saturation

temperature. This releases the dissolved gases, which are then carried with the

excess steam to be vented to atmosphere. (This mixture of gases and steam is at

a lower than saturation temperature and the vent will operate thermostatically).

The deaerated water then falls to the storage section of the vessel.

A blanket of steam is maintained above the stored water to ensure that gases are

not re-absorbed.

Water distribution

The incoming water must be broken down into small drops to maximise the

water surface area to mass ratio. This is essential to raising the water

temperature, and releasing the gases during the very short residence period in

the deaerator dome (or head).

Breaking the water up into small drops can be achieved using one of themethods employed inside the dome's steam environment.


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Deaerator water inlet options

Fig.11


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The major difficulties that may be encountered with a pressurised deaerator, and

their possible causes.


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Fig.13

Turbine

Introduction and Summary

heat is a byproduct of power generation, steam turbines normally generate

electricity as a byproduct of heat (steam) generation. A steam turbine is captive

to a separate heat source and does not directly convert fuel to electric energy.

The energy is transferred from the boiler to the turbine through high pressure

steam that in turn powers the turbine and generator. This separation of functions

enables steam turbines to operate with an enormous variety of fuels, from

natural gas to solid waste, including all types of coal, wood, wood waste, and

agricultural byproducts (sugar cane bagasse, fruit pits, and rice hulls). In CHP

applications, steam at lower pressure is extracted from the steam turbine and

used directly or is converted to other forms of thermal energy. Steam turbines

offer a wide array of designs and complexity to Steam turbines are one of the


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most versatile and oldest prime mover technologies still in general production.

Power generation using steam turbines has been in use for about 100 years,

when they replaced reciprocating steam engines due to their higher efficiencies

and lower costs. Conventional steam turbine power plants generate most of the

electricity produced in the United States. The capacity of steam turbines can

range from 50 kW to several hundred MWs for large utility power plants. Steam

turbines are widely used for combined heat and power (CHP) applications.

Unlike gas turbine and reciprocating engine CHP systems where match the

desired application

And/or performance specifications. Steam turbines for utility service may have

several pressure casings and elaborate design features, all designed to maximize

the efficiency of the power plant.

For industrial applications, steam turbines are generally of simpler single casing

design and less complicated for reliability and cost reasons. CHP can be adapted

to both utility and industrial steam turbine designs.

Turbine

Turbine out put

(At generator terminals)


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Live steam

- Pressure 84.0 atm

- Temperature 515 C

- Flow 56.8 T/h

Exhaust to condenser

- Pressure 0.10 atm

- Power output 12000KW

Extraction steam

- Pressure 9.0 atm

- Temperature 262 C

- Flow 18.8 T/h

Bleed steam

- Pressure 2.92 atm

- Temperature 179 C

- Flow 4.7 T/h

Turbine special instrumentation

Over speed


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Manufacturer Woodward, USA

Probe type Magnetic Pick up type, 5430933

No. of pieces 2

Linearity range 100 Hz-32 Hz

Air gap-min 1 mm

Speed

Manufacturer Guardian

Probe type Magnetic Pick up model

No. of pieces 3

Linearity range 100 Hz-32 Hz

Air gap-min 1 mm

Axial rotor position in the thrust bearing

Manufacturer Predictech

Probe type TM0180-A05-B05-C12-D05

No. of pieces 1

Probe tip dia. 8.0 mm

Air gap-min 2 mm

Sensor length 120 mm

Bearing vibration (absolute)

Manufacturer Predictech

Probe type TM0180-A05-B05-C12-D05


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Fig.14

Surface condenser

Surface condenser is the commonly used term for a water cooled shell and tubeheat exchanger installed on the exhaust steam from a steam turbine in thermal

power stations. These condensers are heat exchangers which convert steam

from its gaseous to its liquid state at a pressure below atmospheric pressure.

Where cooling water is in short supply, an air-cooled condenser is often used.

An air-cooled condenser is however significantly more expensive and cannot

achieve as low a steam turbine exhaust pressure as a surface condenser.
http://en.wikipedia.org/wiki/Shell_and_tube_heat_exchangerhttp://en.wikipedia.org/wiki/Shell_and_tube_heat_exchangerhttp://en.wikipedia.org/wiki/Steamhttp://en.wikipedia.org/wiki/Steam_turbinehttp://en.wikipedia.org/wiki/Thermal_power_stationhttp://en.wikipedia.org/wiki/Thermal_power_stationhttp://en.wikipedia.org/wiki/Heat_exchangershttp://en.wikipedia.org/wiki/Atmospheric_pressurehttp://en.wikipedia.org/wiki/Shell_and_tube_heat_exchangerhttp://en.wikipedia.org/wiki/Shell_and_tube_heat_exchangerhttp://en.wikipedia.org/wiki/Steamhttp://en.wikipedia.org/wiki/Steam_turbinehttp://en.wikipedia.org/wiki/Thermal_power_stationhttp://en.wikipedia.org/wiki/Thermal_power_stationhttp://en.wikipedia.org/wiki/Heat_exchangershttp://en.wikipedia.org/wiki/Atmospheric_pressure


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Surface condensers are also used in applications and industries other than the

condensing of steam turbine exhaust in power plants.

Purpose

In thermal power plants, the primary purpose of a surface condenser is to

condense the exhaust steam from a steam turbine to obtain maximum efficiency

and also to convert the turbine exhaust steam into pure water (referred to as

steam condensate) so that it may be reused in the steam generatororboileras

boiler feed water.

The steam turbine itself is a device to convert the heat in steam to mechanical

power. The difference between the heat of steam per unit weight at the inlet to

the turbine and the heat of steam per unit weight at the outlet to the turbine

represents the heat which is converted to mechanical power. Therefore, the

more the conversion of heat perpound or kilogram of steam to mechanical

power in the turbine, the better is its efficiency. By condensing the exhaust

steam of a turbine at a pressure below atmospheric pressure, the steam pressure

drop between the inlet and exhaust of the turbine is increased, which increases

the amount heat available for conversion to mechanical power. Most of the heat

liberated due to condensation of the exhaust steam is carried away by the

cooling medium (water or air) used by the surface condenser.

The adjacent diagram depicts a typical water-cooled surface condenser as used

in power stations to condense the exhaust steam from a steam turbine driving an

electrical generator as well in other applications. There are many fabrication
http://en.wikipedia.org/wiki/Condensationhttp://en.wikipedia.org/wiki/Efficiencyhttp://en.wikipedia.org/wiki/Steam_generatorhttp://en.wikipedia.org/wiki/Boilerhttp://en.wikipedia.org/wiki/Heathttp://en.wikipedia.org/wiki/Power_(physics)http://en.wikipedia.org/wiki/Pound_(mass)http://en.wikipedia.org/wiki/Kilogramhttp://en.wikipedia.org/wiki/Condensationhttp://en.wikipedia.org/wiki/Steam_turbinehttp://en.wikipedia.org/wiki/Electrical_generatorhttp://en.wikipedia.org/wiki/Condensationhttp://en.wikipedia.org/wiki/Efficiencyhttp://en.wikipedia.org/wiki/Steam_generatorhttp://en.wikipedia.org/wiki/Boilerhttp://en.wikipedia.org/wiki/Heathttp://en.wikipedia.org/wiki/Power_(physics)http://en.wikipedia.org/wiki/Pound_(mass)http://en.wikipedia.org/wiki/Kilogramhttp://en.wikipedia.org/wiki/Condensationhttp://en.wikipedia.org/wiki/Steam_turbinehttp://en.wikipedia.org/wiki/Electrical_generator


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Cooling Tower

Fig.15

Cooling tower

Cooling towers are evaporative coolers used for cooling water or other working

medium to near the ambient wet-bulb air temperature. Cooling towers use

evaporation of water to reject heat from processes such as cooling the

circulating water used in oil refineries, chemical plants, power plants and

building cooling, for example. The towers vary in size from small roof-top units

to very large hyperboloid structures that can be up to 200 metres tall and 100

metres in diameter, or rectangular structures that can be over 40 metres tall and
http://en.wikipedia.org/wiki/Evaporative_coolerhttp://en.wikipedia.org/wiki/Wet-bulb_temperaturehttp://en.wikipedia.org/wiki/Oil_refinerieshttp://en.wikipedia.org/wiki/Chemical_planthttp://en.wikipedia.org/wiki/Power_plantshttp://en.wikipedia.org/wiki/Hyperboloid_structurehttp://en.wikipedia.org/wiki/Evaporative_coolerhttp://en.wikipedia.org/wiki/Wet-bulb_temperaturehttp://en.wikipedia.org/wiki/Oil_refinerieshttp://en.wikipedia.org/wiki/Chemical_planthttp://en.wikipedia.org/wiki/Power_plantshttp://en.wikipedia.org/wiki/Hyperboloid_structure


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Categorization by air-to-water flow

Crossflow

Crossflow is a design in which the air flow is directed perpendicular to the

water flow (see diagram below). Air flow enters one or more vertical faces of

the cooling tower to meet the fill material. Water flows (perpendicular to the

air) through the fill by gravity. The air continues through the fill and thus past

the water flow into an open plenum area. A distribution or hot water basin

consisting of a deep pan with holes or nozzles in the bottom is utilized in a

crossflow tower. Gravity distributes the water through the nozzles uniformlyacross the fill material

Fig.16

Counterflow


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In a counterflow design the air flow is directly opposite of the water flow (see

diagram below). Air flow first enters an open area beneath the fill media and is

then drawn up vertically. The water is sprayed through pressurized nozzles and

flows downward through the fill, opposite to the air flow.

Fig.17


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The salt & pepper collector/selector, and repelling balloon experiments serve to

illustrate the basis of an electrostatic precipitator. In these experiments a type of

electrostatic collector and electrostatic selector are created. This same principle

is used to keep the environment clean today. A description of a more elaborate

demonstration of how an electrostatic precipitator works using a Van de Graff

generator may be found at

The flue gas laden with fly ash is sent through pipes having negatively chargedplates which give the particles a negative charge. The particles are then routed

past positively charged plates, or grounded plates, which attract the now

negatively-charged ash particles. The particles stick to the positive plates until

they are collected. The air that leaves the plates is then clean from harmful

pollutants. Just as the spoon picked the salt and pepper up from the surface they

were on, the electrostatic precipitator extracts the pollutants out of the air.


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BIBLIOGRAPHY

http://www.google.com

http://www.gmail.com

http://www.owmnahar.com

http://www.wikipedia.com
http://www.google.com/http://www.gmail.com/http://www.owmnahar.com/http://www.wikipedia.com/http://www.google.com/http://www.gmail.com/http://www.owmnahar.com/http://www.wikipedia.com/


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INDEX

INTRODUCTION

BOILER

SAFETY VALVE

BOILER STOP VALVE

FEED WATER CHECK VALVE

BOILER CHECK VALVE

BOILER WATER QUANTITY CONTROL

TDS CONTROL

BOTTOM BLOW DOWN

PRESSURE GAUGE

GAUGE GLASS AND FITTING

AIR VENTS & VACUUM BREAKERS

VACUUM BREAKERS

DEAERATOR

WATER DISTRIBUTOR

DESIGN DATA

TURBINE

INTRODUCTION SUMMARY

CONDESOR

COOLING TOWER

BIBLIOGRAPHY


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