A

TRAINING REPORT

ON

“Suratgarh Super Thermal Power Station”Submitted In partial fulfillment of the Requirements for Award of the

Degree of

BACHELOR OF TECHNOLOGY

IN

ELECTRICAL ENGINEERING

From Rajasthan Technical University

Session 2010-2014

Submitted To Submitted By

Mr. M. A. IQBAL AMIT AGARWAL(HOD of EE Dept.) (Electrical Engineering)

Mrs. KOMAL GOHIL(Seminar In charge)

DEPARTMENT OF ELECTRICAL ENGINEERINGMaharishi Arvind College ofEngineering and Research

Center Sirsi road

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CERTIFICATE

This is to certify that the project report entitled “Suratgarh Super Thermal Power

Station” submitted by Amit Agarwal Roll No. 10EMAEE005 to the Maharishi Arvind

College of Engg. & Research Centre, Jaipur in partial fulfillment for the award of the Degree of

Bachelor of Technology in Electrical Engineering is a bonafied record of the project work carried

out by him under my supervision during the year 2013-2014.

Mr. M.A.IQBAL Ms. KOMAL GOHIL(Head of the Department) (Seminar In charge)

Electrical Engineering Electrical Engineering

Prof. (Dr.) R.P.GUPTA

Principle of MACERC

Acknowledgement

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I wish to express my deep sense of gratitude to our H.O.D. of electrical Mr. M.A Iqbal for suggest and valuable guidance for S.T.P.S. It is my proud privilege to express my sense of

gratitude to Assistant engineers for providing me adequate facilities to undergotraining at S.T.P.S.

I am thankful to Mr. B.P. Gautam (SE), Mr. Udaybhan Singh Shekhawat (JEN) &Mr. Sandeep (JEN) for their valuable guidance and co-operation without which itwas not possible to get so much knowledge. I am also grateful to Mr. GhanshyamAgarwal (AEN) & Mr. Ramesh Sethi (AEN) their persistent help and for providingsome of the technical data.

I am equally obliged to all those Engineers Technical personneland operators at S.T.P.S. who gave me their valuable time and rendered practicalknowledge in my training period.

And at last I want to thank my colleagues. Without their help guidance andsuggestions it was not possible to produce this training report.

CONTENTSS.NO TOPIC Page no. REMARK

1. PREFACE

2. ACKNOWLEDGEMENT

3. ABOUT PLANT

4. PLANT FAMILIARIZATION

(i) TURBINE

(ii) BOILER

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(iii) E.S.P.

(iv) COALHANDLING PLANT

(v) ASH HANDLING PLANT

(vi) GENERATOR

(vii) CONDENSER

(viii) MILLING PLANT

(ix) SWITCHYARD

5. CONTROL AND

INSTRUMENTATION CIRCLE

SWAS PACKAGE

ATRS PACKAGE

DDC PACKAGE

FSSS PACKAGE

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PREFACE: -

A very important element in curriculum of an Engineering studentis the Practical Training.

I underwent practical training at "SURATGARH THERMAL POWERSTATION" from 07-06-2013 to 22-07-2013 This is a part of total 45 days trainingprogram incorporated in the curriculum of the Maharishi Arvind College of Engineering & Research Centre B.tech courses.

As I am a student of Electrical Engineering so the training at S.T.P.S. has beenparticularly beneficial for us. I saw the various procedures, processes andequipment used in production of electricity by thermal powers which were studiedin books and this has helped me in better understanding of power generation andconcepts of controlling of instrumentation power.

S.T.P.S. is a very large plant and it is very difficult to acquire complete knowledgeabout it in a short span. I have tried to get acquainted with overall plant functioning.

Amit Agarwal

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ABOUT PLANT: -

Rajasthan Rajya Vidhyut Utpadan Nigam Ltd.(RVUN) established undercompanies Act- 1956 by Government of Rajasthan on 19.7.2000 is engagedprimarily in the business of GENERATION OF ELECTRICITY.

At present the total installed capacity of various Thermal and Hydel PowerStations owned and run by RVUN is 2086.85.

The operation and maintenance of Rana Pratap Sagar(172 MW)

And jawahar Sagar (99MW) Hydel Power Stations (owned by RVUN beingshared project with MP State) is also carried out by RVUN.

With the commissioning of Unit #4 of 250MW at STPS it has become FIRSTSUPER THERMAL POWER STATION OF RAJASTAN.

W Unit #1 of STPS w as commissioned on coal firing on 4.10.1998 andcommercial operation of the unit was declared from 1.2.1999. The unit wasdedicated to the Nation by Hon'ble Chief Minister of Rajasthan Shri Ashok Gehloton 3.10.1999.

The foundation stone for Unit # 3 and 4STPS stage - II was laid by Hon'ble ChiefMinister of Rajasthan Shri Ashok Gehlot on 3.10.1999.

250MW Unit # 2 of STPS was commissioned on 28.3.2000 and was put oncommercial operation from 16.7.2000. It saved Rs.80 crores due to early start ofgeneration. The Unit was dedicated to the Nation by Hon'ble leader of Opposition,Lok Sabha Smt. Sonia Gandhi on 13.10.2000.

The foundation stone for 250MW Unit # 5 under STPS Stage-III was laid byHon'ble Union Minister of Power Shri Suresh P.Prabhu on 12.2.2001.

250Mw Unit # 3 of STPS was commissioned on oil 29.10.2001 and was put oncommercial from 15.1.2002. The unit was dedicated to the Nation by Hon'ble Dy.Leader of Opposition, lok Sabha Shri Shivraj V.Patil on 17.3.2002.

250MW Unit #4 of STPS was commissioned on oil 25.3.2002 and has been put oncommercial operation from 31.7.2002.

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LOCATION OF 1500MW SURATGARH SUPER THERMAL POWERSTATION (SSTPS)

The resinous project of Rajasthan, the Super Thermal Power Station, and Suratgarhis situated near village Thukrana about 27 km. from Suratgarh city in Sriganganardistrict. The site was considered an ideal location for setting up a thermal powerstation due to availability of land, water, transmission line and cheap labour.

A total land area of 5029 bighas been acquired for the power station and 12 km.long constructed from national highway no. 15 near Birdhwal railway station toplant site.

A private railway line of 17 km. has been constructed for coal supply from railwaystation to plant site along with private railway station at Birdhwal and at STPS site.The water availability is also good because the INDRA

GANDHI CANAL is 5 km. away from power plant. In the STPS

transportation facility is also very good.

Development consultant to the project. The civil work of the powerhouse buildingand township were awarded to m/s RSBCC Ltd. Jaipur a govt. of Rajasthanundertaking.

THERMAL POWER PLANT

A thermal power s t a t ion i s a power p lan t in which the p r ime moveri s s t eam dr iven .Wate r i s hea ted , tu rns in to s t eam and sp ins a s t eamturbine which either drives an electrical generator or does some other work,like ship propulsion. After itpasses through the turbine, the steam is condensed in acondenser and recycled now here it was heated; this is known as a Rankine cycle.The greatest variation in the design of thermal power stations is due to the differentfuel sources. Some prefer to use the term energy center because such facilitiesconvert forms of heat energy into electrical energy.

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GENERAL PLANT OVERVIEW

First of all coal zone and collection of coal comes in miles by the mean of CHP(Coal Handling Plant). CHP is the biggest site of coal like belt conveyors, bunkeror crusher house etc.

Belt conveyor is used to lift the coal, cleaning collection or hammering process inthe Bunker or Crasher House and Stacker &declaimer device is used to store orcollect the coal in coal yard.

The size of coal which enters the mill is about 25mm each. The ball and tube millis used in the power station. The coal, which was entering in the mill,grinds in themill up to the powdered form. This powdered form of coal sends to the boilerFurnace where this coal burns and generate heat.

Initially the liquid fuel (Diesel + Stream) is used to generate the heat. The air isalso used with coal in furnace for generating the flame heat. Water flow in tubewhich is mounted around a wall of boiler, this water comes on the drum aftercrossing the Economizer because the purpose of goes on aborting heat at constantpressure and is evident by rise in the temperature. A stage reaches where waterbegins to boil and there is no rise in temperature at this stage stream is formed.

Burnt coal converts in to ash some one of flue gasses because the temperature offlue gasses is very high so if we went to increase the efficiency of the system theseflue gasses flow in many stages like, Super heater, air preheater & Economizer.

After passing the flue gasses the temperature of steam, which was flows in superheater, is rises. When the flue gasses in the air preheater passes the temperatureincreases. At the last stage when the flue gasses flows in the Economizer thetemperature of water which can feed into boiler dream is also increase.

After passing few stages the flue gasses taken from boiler by IDM (IntermediateDraft Fan) and send to chimney through ESP (Electro Static Precipitator). TheElectro Static Precipitator which use electric force to remove the dust from the

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Boiler drum is situated at the top of the furnace throw the boiler tubes which aresituated in the furnace. The water is used to produce steam. First of all water comesin Economizer after this its temperature increases up to 307°c.

After this water goes in the boiler drum and heater, which are mounted on the topof the furnace, then the water flows in the tubes. These tubes are connected withthe flame in the furnace. Due to heating the water converted into the steam. Thissteam is collected in boiler drum. The temperature of the steam is about 538°c withthe help of super heater.

First of all steam flows threw HP (High Pressure) Turbine at a pressure of150kg/cm2 and there is expansion of steam in turbine at a temperature of 340°c andthe pressure of 340kg/cm2 and gives the mechanical work for this the rotor rotatesat some speed. This steam is again heated with the help of super heater and thisheated steam is send to IP (Intermediate Pressure) Turbine and the steam expand ata temperature of 200°c and pressure is 6kg/ cm2. This expended steam direct sendto LP (Low Pressure) Turbine and expansion of steam in this turbine is doubleflow.

This steam moves the blades of the all their turbines that as these blades rotates onthe same shaft, which are connected to the Generator. As the blade moves are therotor of the generator is also rotates at 3000 RPM at effective load. Thus rotationof the rotor occurs. The magnetic field results for the generation of electricity.

After this water feed into HPB (High Pressure Boiler) by the help of BFP (BoilerFeed Pump). For this the temperature of water is about 250°c. In the last stage thewater is feed into the Economizer. This cycle works regularly and it is same for allunits in this Super Thermal Power station.

COAL FOR STEAM STATION:-

In India, the principal sources of energy are coal amounting to over 95% of thetotal primary energy resources of the country. The coal reserves of obtaining in ourcountry are of the order of 130,000 Million Tones or even more and few reserve isbeing located. The main area where coal mines are located easterner regions Viz.Bihar, West Bengal, central region viz. Singrauli coal fields, Tamilnadu. Smallsource of coal are located in the entire country as well.

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CONSIDERATION FOR THE LOCATION OF THE LARGE

THERMAL PLANT:-

The important aspect to be borne in mind during site selection for a thermal powerplant availability of coal, ash disposal facility, space requirement, nature of land,water, transport facility labor, public problems, size of the plant. Largedevelopment in the thermal power generation calls for proper planning in choice ofsite, climatic condition, unit size, coal requirements and transport, transmissionsystem etc. It is normal practice to consider various alternative sites for locatingthermal plant and work out comparison to arrive at economically feasible location.The preparation of feasibility report for a thermal station requires study under twoheadings viz. area selection and site selection. The area selection study comprisesthe study of factor given below, which are required for the establishment of anyproduction oriented industry. Some of the also applicable when final choice of siteis made.

Supply of row materials, which is the case of thermal station are coal and water,are for extreme importance. Transport facilities to whole the raw materials viz.Coal in this case and the capital equipment. Transmission of the power produced tothe local centers. A labour force of size and quality required but this will not be ofever riding consideration. In our country the migration of labour from one place toanother does not pose very difficult problems. Climatic conditions has also playsan important role in area selection.

PLANT FAMILIARIZATION

TURBINESteam turbine is a rotating machine which CONVERTS HEAT ENERGY OFSTEAM TO MECHANICAL ENERGY.In India, steam turbines of different capacities, varying from 15 MW to 500MW, are employed in the field of thermal power generation.

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Steam turbine is a device which consist heat energy mechanical energy. In India,steam turbine of different capacity varying from 15-500MW, are employed in thefield of thermal power generation. The design material auxiliary system etc. Verywidely from each other depending on the capacity and manufacture of the sets.Therefore the discussion in the chapter will follows the general pattern applicableto almost all type of turbines, with reference to the specific features of 210 MWsteam turbine and 500 MW turbines which from the backbone of the power sectorin India, here is 250 MW turbines are used.

WORKING PRINCIPLES

The Thermal Power Plants with steam turbine uses Rankine cycle. Rankine cycle isa vapour power cycle having two basic characteristics:

1. The working fluid is a condensable vapour which is in liquid phase duringpart of the cycle and

2. The cycle consists of a succession of steady flow processes, with eachprocesses carried out in a separate component specially designed for the purpose.Each constitute an open system, and all the components are connected in series sothat as the fluid circulates through the power plant each fluid element passesthrough a cycle of mechanical and thermodynamic stages.The turbine is of tandem compound design with separate HP, IP and LP cylinder.The HP & IP turbines are of single flow type while LP turbine is of double flowtype; the turbine is condensing type with single reheat. It is basically engineered onreaction principle with throttle governing. The stages are arranged in HP, IP andLP turbines, driving alternating current full capacity Turbo generators.

When steam is allowed to expand through a narrow orifice. Reaction turbine isused in Suratgarh thermal power station. In this turbine in which some expansionof steam in fixed blade and some expansion in moving blade. It assumes kineticenergy at the expense of its enthalpy (heat energy). This kinetic energy of steam ischanged to mechanical energy through the reaction of steam against the blades.After this the rotor rotates with some speed.

SPECIFICATIONS:Type - tandem compound condensing ReactionRated output of turbine - 250 KWRated speed - 3000 RPMMain steam temperature - 537 CRated pressure - 150 kg/cm

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CONSTRUCTION, STEAM FLOWS:-

The steam turbine is a random compound machine with high pressure intermediatepressure and low-pressure parts and HP and LP parts are single flow cylinders andLP parts are double flow cylinder. Rigid couplings connect the individual turbine.The HP turbine has been constructed for throttle governing. The initial steam stopsand control valves. The line leading from the HP exhaust going to the re-heater isprovided with swing check valve, which prevent heat steam from the re-heaterflowing back into HP turbine.

The steam is coming from the re-heater is passed to the IP turbine via to combinedre-heater stop & control valves. Cross-around pipes connect the IP & LP cylinder.Blades are arranged at several points of turbine.

HIGH PRESSURE TURBINE

The outer causing of high pressure HP type turbine is of the barrel type and hasneither other as axial nor a radial flag. This prevents mass accumulation with highterminal stress. The almost perfect rotation symmetry permits maturate wallthickness of nearly equal strength at all section. The inner casing is axially splitand kinematically supported. As the pressure difference across the wall of innercasing is low, the horizontal flag and connection belt can be kept small. The barrel

type casing permits flexibility of operation in the form of short start-up time and ahigh rate of change of load at high initial steam condition. Inlet steam temperatureand pressure is 538°c and 150Kg/cm2. Rotation speed is 3000 rpm whose mediumis steam.

INTERMEDIATE PRESSURE TURBINEThe IP turbine is split axially and is of single shell design. The outer casingaccommodates a double flow inner casing. The steam coming from the reheater ispassed into the inner casing via admission branches which are symmetricallyarranged in the top and bottom halves of the outer casing.

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LOW PRESSURE TURBINE

The casing of the double flow IP turbine is of their three-shell design. The shell isaxial split and has rigid welded construction. The inner shell taking the first rowsof guide blades are attached cinematically in the middle. The turbine has an electrohydraulic governing system blacked up with a hydraulic governing. An electricsystem measures and control speed and output and operates the control valveshydraulic in conjunction with an electro hydraulic governing system permits run upcontrol of the turbine up to rated speed and keeps speed swings following suddenload shedding low. The liner output frequency characteristics can be very closelyset during operation.

The main purpose of governor is to maintain this desired speed of turbine duringfluctuations of load on the generator by varying steam input to the turbine.The governing system in addition to ensuring the falling load-speed characteristicsof the turbine also ensures the following functions:1. The run up the turbine from rest to rated speed and synchronizing with the grid.2. Meeting the system load variations in a predetermined manner, when running inparallel with other machines.3. Protecting the machine by reducing the load or shutting off completely inabnormal and emergency situations.

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TURBINE GOVERNING SYSTEM

The governing system also includes other devices to protect the turbine fromabnormal condition that may arise during operation.In STPS By-pass Governing is used.

BY-PASS GOVERNING

In this system, in general, the steam is supplied through a primary valve and isadequate to meet a major fraction of the maximum load which is called economicload loads less than this, the regulation is done by throttling steam through thisvalve. When the load on the turbine exceeds this economic load which can bedeveloped by the unthrttole full flow through the primary valve, a secondary valve,is opened and throttled steam is supplied downstream, bypassing the first stage andsome high-pressure stages. This steam joins the partially spent steam admittedthrough the primary valve, developing additional blade torque to meet theincreased load.

GOVERNING OF REHEAT TURBINE

In reheat turbines in cases of partial of full load ow off even after the HP controlvalves are fully closed the entrained steam in the reheaters and hot reheat line ismore than enough to speed up the turbine above over speed limits. Hence it isnecessary to provide stop valves and interceptor valves on hot reheat line before IPturbine. While the stop valve is operated controlled similar to HP control valve butat a higher speed range by a secondary of pre-emergency governor as it is called.The valve remains full open at rated speed and starts closing at about 3%overspeed and is fully closed at about 5% over speed.

BOILER

The boiler is the main part of any thermal power plant. It converts the fuel energyinto steam energy. The fuel may be furnace oil, diesel oil, natural gas or coal. Theboilers may be fired from the multiple fuels.The boiler installed in S.T.P.S. are made by M/s BHEL . Each of the boilers aresingle drum, tangential fired water tube naturally circulated over hanged, balanceddraft, dry bottom reheat type and is designed for pulverizing coal firing with amax. Continuous steam output of 375 tons/hour at 138 kg/cm2 pressure and 540degree cent. Temp. The thermal efficiency of each boiler at MCR is 86.8 %. Fourno. Of bowl mills have been installed for each boiler. Oil burners are provided for

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initial start up and stabilization of low load .Two E.S.P. (one for each boiler) isarranged to handle flue gases from the respective boilers. The gases from E.S.P.aredischarged through 180 meters high chimney. I.D. fan and a motor is provided nearthe chimney to induce the flue gases.Boiler is an equipment which is used to generate the steam. The steam gives amain role for generate for the electricity. Initially water entered the boiler at atemperature of 300°c and gives output temperature is 500°c of steam. For thispurpose Drum, Economizer, Pre heater, Super heater equipments are used. A pathof water which was comes in boiler as given below:-

Condensate water comes in the LPH (Low Pressure Heater) with the help tubes andwater goes in the Dearator. Dearator is a devise which is use to remove the oxygenpractical in water. Dearator water comes in the high pressure heater with the helpof boiler feed pump, after this water comes in Economizer and the temperature ofwater 360°c and last stage water comes in boiler drum after this water flows in thetubes and converts in steam.

IMPROVED MEATHOD OF HEATING OF BOILER

The saving of latent heat of the steam by evaporation of water above criticalpressure of the steam. Heating of water can be made by mixing the superheatedsteam. The mixing phenomenon gives highest heat transfer coefficient. The overallheat transfer coefficient can be increase by increasing the water velocity inside thetube and increasing the gas velocity. Boiler furnaces have negative pressure orvacuum because the flam has not entered in outermost area of boiler. Coal nozzleliquid oil nozzle or air nozzle rise are provide at all corners in the boilers. Here iswater tube type boiler used for these tubes mounted on walls of boiler. Anelectrostatic precipitator is a large, industrial emission-control unit. It is designedto trap and remove dust particles from the exhaust gas stream of an industrialprocess. Precipitators are used in these industries-

• Power/Electric• Cement• Chemicals• Metals• Paper

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GENERAL CONSTRUCTION OR OPERATION

This boiler has divided by into these zones. In the zone first transfer is preheatedby radiation as the flam in the zone is diffused yellow flam, which radiates muchmore than the premixed blue flam. As the burnt gases upward and secondary air isadded.

The effect of radiation is reduced, becomes predominate as the flam changes fromdiffused to premix. The space marked by R+C receives heat by convention as wellas radiation provided suitable heat transfer surface is including into path. The heatinto zone 2 & 3 takes place mainly convention. Zone two is identifying as high

temperature and 3 as low temperature zone. Zone two is preferably for locatingsuperheated air. Air is preheated because we want to reduce the surface arearequirement. Zone three is used for economizer.

OPERATION

When the heated water comes in the drum and the flow in the heater which issituated in the bottom of boiler. Initially the liquid fuel is used to generate the heat.The air is also used with coal powder in the furnace of boiler for generate the flameheat. A stage reaches when water begins to boil without temperature change at thisstage steam is formed and according to density this steam goes in the drum andthen turbine.

MAJOR PARTS OF A BOILER

In thermal plant boiler consists of many parts as discussed below:-

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FURNACE

Furnace is the primary part of boiler where chemical energy available in fuel isconverted into thermal energy by combustion.

Dry bottom furnace is used at STPS boiler. In which selected coal of nonsloggingtype will be encountered in the furnace. Normally a maximum of 20% of the totalash may be collected as slag at bottom of furnace while the rest is carried awayalong with flue gases.

STEAM DRUM INTERNALS

Steam drum as storage tank which is used to store the steam and water. Thefunction of the steam drum internals is to separate water and steam from themixture generated in the furnace walls and to remove the desired solid content ofthe steam to below the acceptable limit.

SUPERHEATER

Super heater is main for raising the steam temperature above the saturationtemperature. The introduction of advanced steam cycle in modern boilers hasplaced in greater burden on reheated for the 165 bar boiler is approximately 50%.

SH (Super Heater) can be classified into convention and radiation type accordingto heat transfer process.

AIR PREHEATER

The air preheater is now essential boiler auxiliary, because hot air is necessary forrapid and efficient combustion and also for drying coal in the milling plant.

There are two main type of air preheater in use today: static recuperative plate ortube type and the rotatory regenerative type. Here in STPS rotator regenerativetype is used.

1. Heating element - Hot end, Hot intermediate, Cold endMaterials - Carbon & Corten steel2. Rotor main drive motor - 11 kW, 1450 rpm, 50 HzCoupling - Fluid coupling 11.5 fcu

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2. BearingGuide bearingSupport bearingThermostat3. Oil capacityGuide brg. HousingSupport Brg. Housing4. Steam Coil AirpreheaterNumber of steam Coil APHInstalled positionDesign PressureDesign Temperature

-Spherical roller bearing-Spherical roller thrust-Burling thermostat

-25 lt.-150 lt.

-2 Nos per boiler-Vertical-20 kg/cm2-2500C

Weight of One steam coil APH -1950 kg.

ECONOMIZER

The purpose of the economizer is to preheat the boiler feed water before it isintroduced into the steam drum and to recover some of the heat from the fluegases.

CONDENSER

The functions of condenser are:1. To provide lowest economic heat rejection temperature from the steam. Thussaving on steam required per unit of electricity.2. To convert exhaust steams to water for reuse this saving on feed waterrequirement.3. Deaeration of make-up water introduced in the condenser.4. To form a convenient point for introducing makes up water.

IN STPS RVUN SURFACE CONDESER is used.

SURFACE CONDENSER

This type is generally used for modern steam turbine installations. Condensation of

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exhaust steam takes place on the outer surface of the tubes, which are cooled bywater flowing inside them. The condenser essentially consists of a shell, which

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encloses the steam space. Tubes carrying cooling water pass through the steamspace. The tubes are supplied cooling water form inlet water box on one side anddischarged, after taking away heat form the steam, to the outlet water box on theother side. Instead of one inlet and one outlet water boxes, the may be two or morepair of separate inlet-outlet water boxes, each supplying cooling water to a separatebundle of tubes. This enables cleaning and maintenance of part of the tubes whileturbine can be kept running on a reduced load.

Description of condenserThe condenser group consists of two condensers, each connected with exhaust partof low pressure casing. A by-pass branch pipe has interconnected these woecondensers. The condenser has been designed to create vacuum at the exhaust ofsteam turbine and to provide pure condensate for reusing as feed water for theboilers. The tube layout of condenser has been arranged to ensure efficient heattransfer from steam to cooking water passing through the tubes, and at the sametime the resistance to flow of steam has been reduced to the barest minimum.350% capacity condensate pumping sets are installed for pumping the condensatefrom condenser to the deaerator4 through low-pressure heaters. Two pumps are fornormal operation and one works as stand by pump.

Materials for Condenser tubes

Selection of tube material mainly on the quality of cooling water and the cost.Coppers alloys are preferred as copper has very high heat transfer coefficient. Butas copper has very little mechanical strength; it has to be

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reinforced by alloyingwith other metals.Stainless steel tubes has also been used and has good corrosion resistance thoughheat transfer coefficient is quite lower ht an the copper alloy.

TECHNICAL DATA

Design C.W., temperature 33°c

Cold water temperature 8.31°c

Cold water flow quantity 35,000m3/hr.

No. of C.W. passes 2

No. of tubes 15,664

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REGENERATIVE FEED HEATING SYSTEMIf steam is bled from a turbine and is made to give up its latent and any superheat itmay possess, to a heater this system is called regenerative, because the fluid givesup heat, which would be otherwise wasted, to the fluid whilst in another state toraise its temperature. The highest theoretical temperature to which the feed watermay be raised in the heater is the saturation temperature of the bled steam. There isan optimum point at which the steam is bled form the turbine once a feedtemperature is selected, a tapping point near the stop valve produces no gain inefficiency as practically live steam is used for heating.

REGENERATIVE SYSTEM OF 250MW UNITThe regenerative system of the turbine consists of four low-pressure heaters, twogland coolers, one deaerator and three high-pressure heaters. The condense isdrawn by condensate pumps from the hot well of condenser and is pumped to thedeaerator through gland coolers and low pressure heaters where it is progressivelyheated up by the steam extracted from seals and bled points of the turbine. Thedrain of condensate steam on LP heaters No. 2,3 and 4 flows in cascade and isultimately pumped into the main condenasate line after heater No.2 or flows tocondenser. The feed water after being deaerated in the deraerator is drawn buy theboiler feed pump and pumped to boiler through high pressure heaters where it isheated up by the bled steam from the turbine. The drain of condensed steam of HPheaters flows in cascade and under normal load conditions flows to the deaerator.

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HP-LP BYPASS SYSTEMThis bypass system has been provided to allow the steam generator to build up,during start-up, matching steam parameter with the tribune. The steam generated isdumped into the condenser, thus avoiding loss of boiler water. This system enablesstarting of he unit of sliding parameters and also facilitates hot restarting of theunit.In the event of loss of load on the turbine, the bypass system disposes the steamproduced by; the boiler automatically to he condenser without affecting the boileroperation. The bypass system had two sections: HP & LP. The HP-Bypass systemdiverts the steam before main steam valve to he cold reheat CRH line. HP Bypasssystem also reduces the rated steam parameters of the incoming steam from thesuperheated to the steam condition expected in the CRH line (i.e. steam temp. andpressure after HP turbine exhaust).

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The LP Bypass diverts the incoming steam from hot reheat line before interceptingvalves to he condenser after reducing the HRH steam parameters to the conditionsapproximately to that of LP steam turbine exhaust steam.HP Bypass station is utilised for the following tasks:1. To establish flow at the outlet of superheated for raising boiler parametersduring starts up.2. To maintain or controls steam pressure at pre-set value in main steam line duringstart up.3. To warm up the steam lines.4. To control steam temperature down of HP bypass at the reset value

LP Bypass station is utilised for the following tasks:1. Control of steam pressure after reheater.2. Establish flow of steam from reheat lines to condenser by its opening,proportional to the opening of HP bypass valves.

DEAERATERCondensate from hot well is pumped to de aerator by condensate extraction pump.Functions of de aerator are: -1. Removal of dissolved air/oxygen in boiler water.2. Chemical dosing for maintaining quality of boiler water.3. Regenerative heating of feed water for increasing its temperature and efficiencyof plant.4. Storage of feed water in water/steam cycle.

BOOSTER PUMP

WORKING:

50 % tandem boiler feed pump sets are supplied to this contact, three pump sets foreach boiler. Two sets are run in parallel, supplying each boiler, with one pump set

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being on stand-by. Each pump set consists of a "FA1856" booster pump, directlydriven form one end of the shaft of an electric driving motor, and a "FK6D30'boiler feed pump driven from the opposite end of the motor shaft through avariable speed turbo-coupling. The drive is transmitted, in each case through aspacer type flexible coupling. The bearings in the booster pump and pressure stagepump and in the motor are lubricated from a forced lubricating oil systemincorporated in the turbo coupling. The booster pump is a single stage, horizontal,axial split casing type, having the suction and discharge branches on the casing

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bottom half, thus allowing the pump internals to be removed without disturbing thesuction and discharge pipe work of the alignment between the pump and the motor.The pump shaft is sealed at the drive end and the non-drive end by mechanicalseals which are flushed by a supply of clarified water.

TECHNICAL DATA:Pump typeDirection of rotation(Viewed from drive end)Liquid pumpedSuction temp.Flow rateEfficiencyInput powerSpeed of pump

Components of Booster Pump:• Pump Casing• Rotating Assembly• Journal and Thrust bearing• Bearing Housing• Mechanical Seals• Motor / Pump Casing

BOILER FEED PUMP

WORKING:

The FK6D30 type Boiler Feed Pump is a six stage, horizontal centrifugalpump of barrel casing design. The pump internals are designed as cartridge whichcan be easily removed for maintenance without disturbing the suction anddischarge piping work or the alignment of the pump and the turbo coupling. Thepump shaft is sealed at the drive end and non-drive end by

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-FA1856-Anti - clockwise

- Boiler Feed Water-161.10C-490 m3/hr.-81 %-151 KW-1485 rpm

mechanical seals, eachseal being flushed by water in a closed circuit and which is circulated by the actionis cooled by, [assign through a seal cooler, one per pump, which is circulated withclarified cooling water. The rotating assembly is supported by plain white metallined journal bearings and axially located by a Glacier double tilting pad thrustbearing.

27

TECHNICAL DATA:Pump typeNo. of stagesDirection of rotation(Viewed form drive end)Suction temp.Design flowEfficiencySpeedInput powerDrive MotorManufacturerRatingSpeedElectrical supply

Components of Boiler Feed Pump

• Pump Casing• Discharge Cover• Suction Guide• Ring Section Assembly• Mechanical Seal• Journal and Thrust bearing• Bearing Housing• Hydraulic Balance• Flexible Coupling

The lubricating oil for the journal and thrust bearings, of the booster pump andboiler feed pumps and the drive motor will be supplied form the lubrication oilsystem associated with

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FK6D306Anti - clockwise

161.10C490 m3/hr.81 %5310 rpm3322 KW

B.H.E.L., Haridwar3550 KW1492 rpm6.6 kv, 3-ph, 50 Hz

the hydraulic coupling and should be as follows:

Condensate Extraction Pump

TECHNICAL SPECIFICATIONSTypeDirection of rotation viewedSuction temp.

29

EN 8 H 32Clock-wise46.10C

Sp. GravitySpeedPower absorbedEfficiency

0.99011485266 KW78%

WORKING:

The condensate Extraction Pumps are of the vertical, eight stage, Centrifugalcanister type, with the driving motor supported on a fabricated head piece and theeight inter connected pump stage are suspended below the head piece. The pumpdischarge branch and suction branch are formed on the head piece above floorlevel. The eight pump stages are contained within a fabricated canister, and eachstage casing is located by spigot and secured together with bolts, nuts and lockwasher. The canister is suspended and secure to a foundation ring with screws. Thehead piece is also secure to the canister with screws. Each pump directly driventhrough a flexible coupling by a 325 KW electric motor.

Components of Condensate Extraction Pumps:• Head piece• Foundation Ring• Canister• Stuffing Box Assembly• Thrust andjournal bearing assembly• Coupling• Driving motor

In SURATGARH THERMAL POWER PLANT, there are three fans:

1. F.D.FAN (Forced fan)2.1.D.FAN (Induced fan)3. P.A.FAN (Primary fan)

FORCED DRAFT FAN

In the Axial Reaction Fans (Type AP), the major part of (about 80 %) energytransferred is converted into static pressure in the impeller itself. The rest of theenergy is converted into static pressure in the diffuser. These fans are generallydriven at constant speed. The flow is controlled by varying the angle of incidenceof impeller blades. It therefore becomes possible by this process to achieve high

30

efficiencies even during part load operation. The blade pitching operation isperformed by mechanical linkages connected to a hydraulic servomotor which isflanged to the impeller.

TECHNICAL DATAApplicationNo. offMedium handledOrientationCapacityTemp. Of mediumSpeedCouplingDrive motor RatingSpeedFan WeightType of fan regulation

Forced Draft Fan2Atmospheric AirVertical Suction and Horizontal Delivery105.2 m3/Sec450C1480 rpmRigiflex coupling700 KW1480 rpm8 TonesBlade Pitch Control

When looking in flow direction, the fan consists of the following Components:

• Suction chamber• Fan Housing• Rotor Consisting go shaft, one impeller with adjustable blades with pitch

control mechanism.• Main bearings (Antifriction bearings)• Outlet Guide Vane housing with guide vanes• Diffuser

FAN ACCESSORIES

RIGIFLEX SHAFT COUPLING

The fan shaft is connected to the motor shaft by means of Rigiflex couplings.

OIL CIRCULATION SYSTEM

The oil system consists of an oil tank, two pumps(on Stand by), filters, coolers andnecessary fitting.

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DRIVE MOTORThese fans are driven by constant speed Synchronous Induction motors.

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SILENCERThese fans are provided with a silencer to attenuate. Airborne noise to acceptablelevel.

LUBRICATIONThe lubrication oil for the fan bearings ate supplied by the centralized oil pumpswhich supply oil for the hydraulic servo meter also.Recommend Oil:Servo Prime 68 of IOCTurbinal 68 of HPC

INDUCED DRAFT FAN

Radial fans manufactured are single stage, single/ double suction, simplysupported/overhung centrifugal machine which can be used to handle fresh air aswill as hot gases in power plant application. In this, the medium handled enters theimpeller axially and after passing through the impeller leaves radially. A large partof the energy transferred to the medium is converted into kinetic energy as themedium passes through the impeller. The spiral casing converts part of the kineticenergy in the medium to pressure energy. These fans are generally driven byconstant speed motors. The output of the fan is usually controlled by inlet dampersor inlet guide vanes or by varying the speed of the fan by suitable speed controldevice.

TECHNICAL DATAApplicationNo. offTypeMedium handledOrientation

CapacityTemp. of mediumSpeedCouplingDrive motor RatingSpeedFan Weight

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Induced Draft Fan3NDZV 33 SFlue Gas450 Top incl. Suction Bottom, horizontalDelivery250.5 m3/Sec1540C740 rpmHydraulic Coupling1750 KW740 rpm52.7 Tones

The major sub-assemblies of the fan are as follows:

• Impeller with shaft assembly• Bearings and thermometers• Suction chamber and spiral casing• Flow regulation devices• Shaft seals• Couplings

The fan is drive by an electric motor. The fan bearings are lubricated by means ofoil lubrication. The oil must not foam during operation. Foam removing agentscontaining silicon must not be utilized. The oil must have good anti-corrosionproperties.

PRIMARY AIR FAN

PA Fan is same as forced draft fan. Only the differences is that in this fan there aretwo stages AP fan(Axial Profiles fan), the two impellers are connected by means ofa link rod, with this we can operate both the impeller blades synchronously.

TECHNICAL DATA

Application Primary Air FanNo. off 3Type AP 2 17/12Medium Handled Atmospheric AirSpeed 1480 rpmRating 1400 KWFanwt. 10.8 tones

CONDENSATE EXTRACTION PUMPS

This is used to feed the condensate water into low-pressure heaters. This pump airof the vertical, eight stage, centrifugal types. In steps, three pumps are located withcondenser with each boiler. In running conditions to the pumps are used to increasethe efficiency of the boiler section of the plant.

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E.S.P.

E.S.P. is a highly efficient device for extraction of suspended particles andfly ash from the industrial flue gases.Performance of Electrostatic Precipitator (ESP) deteriorates over the years andthey are not able to meet the required emission standard. In the present paper wediscuss the performance of ESP's in a power plant, which is situated right in thecentre of a mega city. As the power plant is surrounded by densely populated areaof the city the other emission control methods like flu gas treatment with S03/NH#cannot be applied due to a further risk of pollution. Pulse charging methed has alsolimited scope of further enhancing the particulate collection efficiency of ESPS.The decision was taken to put additional unit of ESP along with existing unit ofESP. Performance Guarantee (PG) tests were carried out for the whole ESPsystems. Samples were collected from the inlet and outlet of the each ESP systems.The collection efficiencies were determined for individual and for the whole set ofESPs. The results indicate a significant deterioration of collection efficiency oldESP unit at the level of (90-93)% against designed value of more than 99%. Thenew ESP unit, which was put ahead of old ESP unit, was operating in the range of(93-96)% of collection efficiency. The over all Collection efficiency of the systemexceeded all the time more than 99.5%.

An electrostatic precipitator (ESP) is integral parts of coal based thermal powerplant to control particulate emissions. ESPs are being used at DVB IP stations inDelhi. Initially BHEL-make ESPs were being used for 60 MW boiler at unit-5 ofDVB IP stations. Over the years the performance of BHEL ESPs deteriorated andthey are not able to meet the required emission standards. As IP station is right inthe heart of city, the other emission control methods like flue gas treatment withS03/NH3 can not be applied due to a further risk of pollution. Pulse chargingmethod has also limited scope for improving the particulate collection efficiency ofESP. The decision was, therefore, taken to put additional units of ESP along withexisting ESPs supplied by BHEL. In order to meet the particulate emissionstandards, DVB IP station has acquired additional set of ESPs from Alstom PowerBoiler Ltd., Shahabad-585229. These ESPs are working in series with existingBHEL ESPs for 60 MW boiler at DVB IP station unit-5, Delhi. The flue gasescoming out from the boiler are allowed to flow through two passes namely A andB. A set of ESPs consisting of ALSTOM ESPs followed by BHEL ESPs are fixedin each of the pass. The clean flue gases from pass A and pass B are combined andthen passed through stack. The probing ports are available at the inlet and outlet ofAlstom ESP. The inlet ports for BHEL ESP are the outlet ports for the two

35

ALSTOM ESPs. However, the outlet probing ports for the A&B passes of BHELESPs are common after ID fan but before entry to stack.

The emission level from the power plant depends on the stable operation of boilerand efficient functioning of ESPs. Performance Guarantee PG tests unit-5 of DVBIP station Delhi were to be carried out when the boiler got stabilized at about 60%load in the first week of March 2002. For carrying out dust loading tests at variousparts of ESP systems, the services of SIMA (Sophisticated Industrial MaterialsAnalytic) Labs Pvt. Ltd. Okhala Industrial Area, New Delhi- 110020 wereacquired. Simultaneous dust loading test were carried out in a given pass at theinlet of ALSTOM ESP, at the common junction of outlet/inlet of ALSTOM/BHELESPs and at final out let of ESP systems. The test were conducted in pass A and B.Two sets of readings were obtained at different times on each points. Besides themeasurements of dust concentration, other parameters like flue gas flow rates, fluegas temperatures, pressure drops etc. were also measured. A record of electricaloperating parameters of each field in ALSTOM and BHEL ESPs were kept besidesboiler side reading of unit 5.

(i) The stack monitoring parameters are listed in Tablel. The measured parametersare flue gas temperature (0C); inlet/outlet and final velocities in side the duct (m/s),flue gas volume flow rates (NM3/hr), and suspended

particulate matter, SPM, (mg/ NM3). In all 12 sets the measurements have beentaken at different points in the two passes A and B. The reading recorded havebeen depicted in figure. 1 enclosed.

(ii) The electrical parameters in each field of ALSTOM ESP have been recordedduring the investigation periods. Primary voltage (V) and current (A), secondaryvoltage (kV) and current (mA), spark rate per minute in all six fields (3 each inpass A and B) have been recorded at different times.

(iii) The operative electrical parameters in BHEL supplied ESPs, which followingthe ALSTOM make ESPs in each pass have also been recorded at differentintervals during investigations.

Based on the observations made during investigations the particulate collectionefficiency of ALSTOM ESPs and overall efficiencies of the system have beenevaluated and other observations have been made. The results are summarized asfollows:

(1) If one observes the volume flow rate of flue gas (QE/Hr) in table 1, the total

36

volume of gas flow on pass (A) +pass (B)is more than the final outlet flow. A

37

similar trend is observed through out the investigation. This shows leakage ofgases in the path between the outlet of ESPs and final out let. (Ref. in the figure 1).The gas flow rate vary between 178638 Nm3/hr (49.62 Nm3/sec) to 190774Nm3/hr (52.99 Nm3/sec). The leakage of gas varies in the range (6- 10)%. ft mightresult in higher reading of SPM (Solid Particulate Matter) per unit of volume thanthe actual, as the flue gas will leak leaving SPM behind. Pluging the leakage willresult in actual observed values.

(2) The operating parameters are as follows:

Gas flow rate -101.6 m3/s, Gas temperature - 130 0C

Specific consumption rate - 0.8 Tons/MW/hr.

Electrical load - 37 MW, Coal ash - 40%, Fly ash - 90%

- 29.13 gm/ m3 at 130 0C - 43.0 gm/NM3

. . . . 3 7 * 0 . 8 * 0 . 9 * 0 . 4 . _inlet dust concentration — -----------------------gm/m3

101.6*3600 b

Thus, this value matches well with those measured values of SPM (mg/ NM3) andshown in table 1 & figure 1.

(3) The observed values shown in table 1 has been used to calculate the collectionefficiencies of ESP systems. The dust collection efficiency has been calculatedusing following relations

i) Dust collection efficiency of ALSTOM ESP/BHEL ESP

Inlet dust loading at pass AorB- Outlet dust loading at pass A or B

Inlet dust loading at pass A or B

ii) Dust collection efficiency of overall system:

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Inlet dust loading at pass A- Final outlet

Inlet dust loading at pass A

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iii) Theoretical efficiency of ESP may be calculated by using Deusch- Andersonequation as follows:

where,

A = Total collection area of plates (m2)

Q = Gas flow rate (m3/s)

W = Average migration velocity of charged dust particles (m/s)

Collection efficiency=l-exp(- - w)

The dust collection efficiencies of ALSTOM ESPs and overall collectionefficiencies have been calculated using

expressions in l and 2 and are shown in Table A. As one can observe from table A,the collection efficiencies of ALSTOM supplied ESPs in pass A and pass B variesbetween (93.48-95.74) % with average 94.60 % . While the overall collectionefficiencies of the whole systems varies between (99.59-99.73) % with average99.63 %. The designed values of dust collection efficiency of ALSTOM suppliedESPs is 93 % at gas flow rate of 148 M3/s (94 Nm3./sec). As in present case theESP is operating at gas flow rate (—101.6 NM3/s), the efficiency is likely to beeffected if all other operating conditions remain same (equation at iii). Thecollection efficiencies of BHEL supplied ESPs varies between (90.60-93.86)%with average 93.23%.

The electrical parameters for all the ESPs have been noted.. There are five fieldsin each pass of ESP. The values of charge ratios have been kept constant. Thesevalues are 1:7 for 1st field, 1:11 for second field, 1:15 for third field, 1:17 forfourth field and 1:21 for fifth field. Only in the 1st field some back corona hasdeveloped as indicated by sparks. Otherwise most of the time, back corona hasbeen suppressed as no sparks have been observed in other field. Secondaryvoltages in the five fields vary from 35 kV in first field to —22 kV in last field.Similarly secondary current in first field (— 65 mA) are higher than in last field (—14 mA). Normal practice is however to set lower current in initial field and highercurrents in final fields.

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The variation of electrical parameter of ESP supplied by ALSTOM has been noted.As may be observed quite high secondary voltages high (>50 kV) have beenmaintained in all three field and both pass of ESP. No sparks have been observedduring the operation, which shows the absence of back corona. As the voltagemaintained are high, a higher migration velocity is expected resulting in highercollection efficiency.

Plant load varies from 30 MW to 39 MW during the observation period. The gastemperature are almost constant; 136 0C in pass A and 130 0C in pass B. Temp.difference of 4-8 0C between airheater outlet to ESP inlet gives an impression ofconsiderable air infiltration which dilutes the flue gases coming from boiler.Mechanical Draught is produced by Forced Draught (FD) and Induced Draught(ID) fans. FD fan, which is installed at the inlet of air preheater consumes lesspower and operates at near constant current rating (21 Amp and 23 Amp for pass Aand B respectively). The ID fans are located near the stack, they handle hotcombustion gases and their power requirem constant rating of 48 Amp in bothpasses. The gas flow even at lower Boiler load is more than 100% Boiler loadwhich may overload ID fans resulting sometime puffing effect in the furnace. Theopacity reading is also shown in figure, however, because of their positioning andcalibration problems; these may not be relied upon.

Particle size analysis has been carried for the fly ash samples collected at the inletand outlet of pass-A of the ESP systems. The particle Size are thus been measuredat the inlet and outlet of ALSTOM ESP in pass-A. A GALAI-CIS-1 computerizedInspection system ( Laser based particle size analyzer) has been used for particlesize measurements.

Table 2 and Table 3 show volume distribution of particles in different ranges at theinlet and outlet of ESP respectively. As can be observed from Table2 that around56% of particles are having sizes less than 10 micron , a total of 44% are in largerrange (18.41% in 10-20 micron, 13.31% in 20-30 micron, 10.93% in 30-4- micronand 0.49% in 40-50 micron range). At the outlet of ESP on the other hand, asshown in table7 the fraction of particles up to size of 10 micron goes up to 93%and only 7% are in the range of 10-20% micron range .The sample size was toosmall at the final out let for taking any meaningful size distribution measurements.However the fraction of smaller size particle (<10 micron) should still be more.

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WORKING PRINCIPLE

E.S.P can handle large volume of gases from which solid particles are to beremoved Advantages of E.S.P. are High collection efficiency Low resistancepath for gas flow Treatment of large volumes at high temp.Ability of cope withcorrosive atm.An E.S.P. can be defined as a device which utilized electric forces toseparate suspended particles from flue gases WORKING STEPS : Ionization ofgases and charging of dust particles Migration of dust particles. Deposition ofcharge particles on collector surface. Removal of paE.S.P. consist of two sets ofelectrodes, one in the form of thin wire, called discharge or emitting electrode inthe form of plates. The emitting electrodes are placed in the center or midwaybetween two plates and are connected to-ve polarity of H.V. D.C. source of orderof 37 KV collecting electrodes are connected to + ve polarity. The voltage gradientbetween electrodes creates "CORONA DISCHARGEIonizing the gasmolecules. The dust particles present in flue gases acquire -ve charge anddeposited on collecting electrodes. The deposited particles are removed byknocking the electrode by a process called "RAPPING'DONE BY "RAPPINGMOTORS".

COOLING TOWERS

Cooling towers are heat removal devices used to transfer process waste heat to theatmosphere. Cooling towers may either use the evaporation of water to removeprocess heat and cool the working fluid to near the wet-bulb air temperature or relysolely on air to cool the working fluid to near the dry-bulb air temperature.Common applications include cooling the circulating water used in oil refineries,chemical plants, power stations.

COOLING WATER PUMP

The motor of the CWP has following specification;Type Y1600-16/2150Out Put Power 1600KWStator Voltage 6.6KVSpeed 372rpmFrequency 50HzStator Rated Current 182AStator Connection 2Y

42

Ambient Temperature 50C

43

InsulationWeight

Class B17500Kg

1400S25-116000m3/H370rpm1600KW35000kg25m8.5m

TypeCapacitySpeedPowerWeightHeadNP SHR

CW PUMP

Type is single stage double suction centrifugal pump

The Over-all collection efficiencies for particulate have been improved by puttingtwo ESPs in series. Further improvement is possible on adopting following steps.

♦ Plugging of leakage in the boiler / ESP system upto stack. This will minimiseinfiltration as well as make ID fans operation suitable to create adequate suction inthe furnace.

♦ Operating the boiler at stable load with minimum fluctuation.

♦ Increasing current level of collecting electrodes of BHEL ESPs with lowercurrent in initial fields and higher current in final field.

WATER TREATMENT

INTRODUCTION

The natural water contains solid, liquid and gaseous impurities and therefore, thiswater cannot be used for the generation of steam in the boilers. The impuritiespresent in the water should be removed before its use in steam generation. Thenecessity for reducing the corrosive nature & quantity of dissolved and suspendedsolids in feed water has become increasingly important with the advent for highpressure, critical & supercritical boilers.

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IMPURITIES IN WATERThe impurities present in the feed water are classified as given below -1. Undissolved and suspended solid materials

• Turbidity and Sediment• Sodium and Potassium Salts• Chlorides• Iron• Manganese & Silica

2. Dissolved Salts and Minerals• Calcium and Magnesium Slats

3. Dissolved Gases• Oxygen• Carbon Dioxide

4. Other Materials• Free Mineral Acid•Oi l

RAW WATER AND IMPURITIES

SOURCES

The various sources of water can be broadly classifies as:a) Rain waterb) Surface water (Rivers, Streams, Ponds, Lakes)c) Ground water ( Springs, Shallow wells and Deep Wells)

IMPURITIESThe major impurities of water can be classified in three main groups are:Non- ionic and Undissolved.These are mainly turbidity, slat,mud, dirt and other suspended matter

• .Ionic and Dissolved

• Gaseous Impurities : Carbon Dioxide and Oxygen

REMOVAL OF IMPURITIES

Our major concern is industrial water treatment, whereby, water used directly orindirectly in an industrial process is made suitable for that particular application.The use of water in boilers fro steam generation is an obvious industrial use.

45

Depending on the process, varying degrees of purity of treated water are required.For example, a textile processing unit will require soft and clear water for processuse: a chemical plant or electronic components manufacturing unit will require

46

ultra-pure water containing total dissolved impurities not exceeding 0.5mg/litre orless.

COALHANDLING PLANT

Any of various ways in which coal is grouped. Most classifications are based onthe results of chemical analyses and physical tests, but some are more empirical innature. Coal classifications are important because they provide valuableinformation to commercial users (e.g., for power generation and cokemanufacturing) and to researchers studying the origin of coal.

SPEED REDUCER

Speed Reducers feature wash down coating.

January 10, 2005 - Suited for speed reducers, Stainless Bost-Kleen™ utilizesBisphenol-F type epoxy, which offers chemical, pressure, and thermal resistance toprevent wear and cracking caused by caustic chemicals and high-pressure washdowns as well as scratches that may occur from contact during installation andoperation. Coating is USDA and FDA accepted, BISCC certified, and available onall speed reducers.

The coal handling portion of a power plant can encompass every piece ofequipment from rail, truck, or barge unloading to the conveyors, crushers, andstorage bins. The equipment generally operates intermittently for a set number ofhours each day and does not consume a significant amount of energy. Anestimated, typical power requirement as a fraction of total gross power plant outputis 0.07%. Improvements to the process efficiency are limited primarily to themotors and drives. As the drives deteriorate in function and performance, they canbe replaced with more energy-efficient motors. Additionally, VFDs are alreadyused for certain applications within the coal handling equipment, but for reasonsother than efficiency at low turndown. Specifically, VFDs are used to reduceexcess strains on equipment, such as belts and conveyors during startup, and theirapplication for reducing energy demands at turndown is not significantly

47

applicable due to the intermittent operation of the coal handling equipment.Although VFDs provide more precise control of the operating equipment, which

48

can be considered an efficiency improvement, the reduction in overall plant heatrate is not substantial.

Coal pulverizers are used to provide fine coal particles for pneumatic transport intothe boiler for combustion. Fine coal particles improve the combustion efficiency ofa boiler. The improvement in combustion reduces the amount of coal that must betransported and burned in the boiler and thereby reduces fuel cost and the plantheat rate. Improvements to pulverizer designs have enabled more finely groundcoal and a lower primary air pressure drop through the pulverizer.Ref. 49 Suchimprovements can also be incorporated on older existing units, but may result in aloss in mass throughput. This reduction in throughput is generally greater than thefuel use savings from enhanced coal fineness, thereby reducing the capacity of thepulverizer. If a plant has excess pulverizer capacity, such improvements can beimplemented. If the facility is switching fuels, then such upgrades are probablywarranted. But, based on historical projects, this area of improvement has notyielded significant reductions in plant heat rate unless the machinery was severelydegraded. The costs associated with such projects are significant.

The ash handling system presents some opportunities to switch from a water-sluicing bottom ash system to a dry drag chain system, which can save some powerand water for the plant. But, in general, ash handling equipment is another area ofmaterial handling that does not present much opportunity to economically reduceauxiliary power requirements. An average of the power consumed by ash handlingequipment as a percentage of total gross plant power consumption is 0.1%. Theequipment operates intermittently, similar to the coal handling equipment and,therefore, is not considered a prime area of investment for plant heat rate reduction.

ASH HANDLING PLANT

This plant is used to handles the dust or ash particle that was given by the flu gasesor also in furnace. The methods used for the removal of ash or dust from gases aremany but, for power station application, in STPS. The electrostatic precipitator,which uses electrical forces to remove the dust from the gas steam. In ESP our

49

different steps the process of precipitation:-

50

• Ionization of gases and charging of dust particles.• Migration of the particle to the collector.• Deposition of the charge particles on the collecting surface.• Dislodging of the particles from the collecting surface.

For the purpose of generates the electrical force of there the transfer or

rectifier are consists at the top of ESP.

Ash slurry in boiler is 3KM away from plant with the help of pump house.

In each unit 28 hoppers or fields are consists for the purpose of collection of coal.

GENERATOR

Generator is the electrical end of turbo generator set. It is a cylindrical polesynchronous generator. It is generally known as a piece of equipment that actuallyconverts the mechanical energy of turbine into electricity. The generation ofelectricity is based on the principle of electromagnetic induction.

A generator consists of the following main components and associated

system:-

(1) . Stator

(2) . Rotor

(3) . Excitation system

(4) . Cooling system(5). Sealing system

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STATOR

The stator is the component that embodies the armature core and armaturewinding. It is totally enclosed gas tight fabricated structure. It is the single heaviestload in the whole turbo generator. The major part of this load is stator core. Thestator comprises of an inner frame and outer frame. The outer frame is a rigidfabricated structure of welded steel plates. Within this shell is fixed cage ofgirderbuil circular and axial ribs. The ribs divides the yoke into, compartmentsthrow which hydrogen/air flow into radial ducts in the stator core and circulatesthrow the gas coolers housed in the frame. The inner cage is usually fixed to theyoke by an arrangement of springs to dampen the double frequency vibrationinherent in 2-pole generator. The details of the stator have been shown in the figureon the next page. In large generators (500MW etc.), the frame is constructed as twoseparate parts. The fabricated inner cage is inserted in the outer frame after thestator has been assembled and the winding completed.

STATOR CORE

The stator is built up from a large no of vanished insulated punching or thinsections of thin (generally 0.35 mm to 0.5 mm) steel plates. The use of cooledrolled grain-oriented, loss less steel iron which the punching are made cancontribute to reduction in the weight of stator core for two main reasons.

(1) . There is an increase in core stacking factor which improvement in lamination,cold rolling and in core building techniques.

(2) . The advantage can be taken of the high magnetic permeance of grainorientedsteel to work the stator core at comparatively high magnetic saturation without fearof excessive iron loss or too heavy a demand for excitation ampere-turns from thegenerator rotor.

The slot ventilation holes etc. are punched out in one operation in the stampingsand as such the stampings are rather complicated or accounts of holes and the slotsthat have to be produced. The core stampings are assembled in an inner leavedmanner on core bars. The core consists of several pockets separated by steel spacerfor radial cooling of the core by hydrogen. To ensure a tight and monolithic core,pressing of the punching is done in several stages and completely built, the core us

52

help in pressed condition by mean of heavy non magnetic steel press rings whichare bolted to the end of core bars as additional support is provided to the teeth

53

portion by means of non magnetic fingers held between the core and the press ring.The press rings are tempered on the face toward the core, so that an even pressureis exerted over the end surface of the core when core bars are tighten. Copperscreens provided between the end packets and press rings reduce the end zoneheating.

In order to isolate the stator body and thus foundation from magnetic vibrations ofthe stator core. The core bars are designed to provide elastic suspension of core inthe stator.

STATOR WINDING & INSULATION

Stator core carries the armature winding where the voltage is generated due toelectromagnetic induction. Each stator conductor must be capable of carrying therated current without overheating and the insulation must be sufficient to preventleakage current flowing between earth and phase.

The stator has a three phase double layer short core type bar winding having twoparallel paths. Each coil side consists of glass insulated solid and hollow conductorwith cooling water passing through the latter in case of water cooled conductorsbeing used in higher capacity units. Water is fed to and fro the winding throwTeflon tubes.

The stator winding conductors, both solid and hollow, are transposed about

a non magnetic duct, which provide the flow path for the coolant gas in case of H2cooled generator. In liquid cooled windings the transposed conductors arerectangular tubes. The transposition can be done in no. of ways but mostcommonly used method of transposition is Roebel arrangement.

The rotor is cast chromium, nickel, molybdenum and vanadium steel ingot and it isfurther forget and machined. The rotor forging is then planed and milled to formthe teeth. Very often a hole is bored throw the center of the axially from one end tothe other for inspection. Slots are then machined for winding and ventilation.

54

ROTOR

ROTOR WINDING & RETAINING RINGS

The rotor carries the field windings. Silver bearing copper (containing 0.03 to 0.1% silver) is used for the winding with mica as the insulation between conductors.A mechanically strong insulator such as micanite is used for lining the slots. Laterdesigns of windings for circulation of the cooling gases throw the actualconductors. When rotating at high speed, centrifugal force tries to lift the windingout of the slots and duralumin wedges contain them.

The end turns outside the slots are covered by non magnetic steel retaining endrings are secured to a turned recess in the rotor body. By shrinking or screwing andsupport at the other end by fitting the rotor body.

MILLING PLANT

Coal handling plant deals with the under loading of the coal racks, crushing of coalat different stages to stack the crusher coal at the stock pile to feed the crushed coalto the coal bunkers either directly from the rack or stockpile stacked coal throughdeclaimer.

Coal handling plant is an important consistent of a plant. It provides crushed coalto the bunker from where it is feed to the mill in the coal mill; it gets transformedinto the form of water. Coal wagons are unloaded at the wagon tippler. Here, itgets crushed to 200mm size in the ruler crusher. This is the primary stage crushingof the coal. This coal is feed to the rotatory breaker throw conveyers' belt system.In the rotary barker the size of the coal is reduced up to 100 mm. the secondarystage of crushing this coal. This coal is either stacked at the stockpiles made for the

storage of coal or it is feed directly to the third stage. In the third stage is feedeither from the stacked coal at the stockpile or directly from the rotary barker.While conveying coal to the third stage crusher, as ILMS (In Line MagneticSeparator} comes into the way. Here iron materials pieces etc. get separated.

55

The coal is feed to third stage crusher where it is crushed into size of 10 mm. thiscoal feed to the bunkers from where it is feed to the coal mills. To unload the coalwagons or to crush coal and to stack it and to feed it to coal bunkers. Variousequipments and conveyers are installed in coal handling plant.

Some of the important equipments are listed below:-

• Wagon tippler• Roll crusher• In Line Magnetic Separator• Vibrating Feeder• Apron Feeder• Rotary Breaker• Ring Granulator• Grizzly Feeder

A brief description and working of above equipments is explained below:-

WAGON TRIPPLERWagon tippler unloads wagons. The sides are charged to provide at the wagontippler. The main types of tippler auxiliaries are as

1. Rorary Wagon Tippler - Gravity & Hydraulic Clamping

2. Side Discharge Wagon Tippler - Gravity & Hydraulic Clamping

3. Wagon Pusher

4. Side Arm Charger

5. Wagon Shunting Device

ROLL CRUSHER

Roll Crushers are compression type crushers, and were once widely used inmining. They have, within the last 10 or so years, fallen into dis-favor among

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mining and processing companies. The probable reason is because

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the large mines require very large crushed product output with minimal cost,makesthe roll crusher uncompetitive. The roll crushers are not nearly as productive ascone crushers, with respect to volume, and they do have a little higher maintenanceassociated with them. Roll crushers do, however, give a very close product sizedistribution, and if the ore is not too abrasive, they do not have high maintenancecosts.

IN LINE MAGNETIC SEPARATOR

Type 'A' magnetic separators utilize a number of closely spaced north & southmagnetic "poles" to create a powerful magnetic field capture and retain small tomedium sized tramp metal contaminants. Type 'A' magnet circuits are ideallysuited for applications such as final inspection of high quality consumer foodproduct. Type 'A' magnets are available in a wide range of models each havingmany standard sizes to meet your specific magnetic application and budgetrequirements.

VIBRATING FEEDER

Vibrating feeders are in operation worldwide and can be found in mining andquarry operations, as well as aggregate, chemical, and industrial processes. Someof the more common feeder applications are in coal mining.

APRON FEEDER

TENGL Apron feeders are engineered for heavy duty operation and for primaryand subsequent application stages. These custom-built machines are designed tosuit individual requirement of capacity, size and material handled.

ROTARY BREAKER

A Rotary coal breaker is designed to receive run-of-mine coal. The coal breakerprovides both positive control to the top size and libration of rock from coal.

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RING GRANULATOR

It is a third stage crusher, called ring granulator. This crusher crushes thesecondary crushed into 25 mm coal size. It is driven by HT motor {655 KW}. Thismotor is of the highest rating squirrel cage induction motor in coal handling plant.The crushed coal is then feed to the bunkers throw conveyers belt.

GRIZZLY FEEDER

A mill is a device in which a drum is considered which one rotates on some speedand present ball are also rotates. From this the coal is pulvorised or grained in theform of powder.

Power plant boiler fuel demand is transmitted as a coal feeder speed demand to acoal pulverizer control. A speed controller operates the feeder in accordance withthe speed demand, and a position controller for a hot coal transport air damperpositions the hot air damper to hold the mill outlet

temperature to a set point value and to increase or decrease damper position inaccordance with a feed forward signal representing the feeding speed demand. Aposition controller for a cold air damper regulates the total primary air flow to avalue needed for safe and smooth transport of the

pulverized coal to the boiler burners, and it accordingly acts as a process trim onthe feed forward control applied by the hot damper controller.

The advantage of a ball mill may be summarized as:-

1. High output possible up to 50 tones per hour.

2. No maintains over a long period.

3. High availability.

4. This keeps primary air power requirement to minimum.

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On the other hand it has some disadvantages also as listed below:-

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1. High power consumption.

2. Some problem with control of coal level with in the mill.

TECHNICAL DATA:-

Application

System type

Eff. Dia. of shell

Eff. Length of shell

Shell (rpm)

Total weight of balls

No. of lines

Main motor reducer gain

ratio

Bearing type

Coupling type

Lubricant oil temp.

Main motor rating

Auxiliary motor rating

MAIN PARTS OF MILL:-

• Coal Feeder• Coal Classifier• Speed Reducer• Valve or Damper

Ball tube mill

Pressurized direct

firing

4.7 m

7.2 m

15 RPM

80 tones/period

600 each mill

12.5:1

ball and roller

bearing

Fluid coupling

40oc

2400

KW

1500

KW

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SWITCHYARD

A switchyard provides a connection point for transmission lines of the samevoltage. The proposed Eastern Terminal switchyard requires approximately 4hectares of land, However, Western Power is looking for an area of approximately20 hectares to ensure that the switchyard can be adequately screened and toaccommodate a terminal substation, in case future major development in thehillsarea trigger the need for increased power.

Current electricity forecasts indicate that it is extremely unlikely that theswitchyard would be developed into a substation. Significant increases in powerdemand from major industrial development in areas to the east of the EasternTerminal switchyard site would need to occur for the switchyard to be developedinto a substation. Based on current State and Local Government planning, there isno foreseeable need to develop the site beyond the 4 hectares switchyard.

HIGH TENSION SWITCH-GEAR

OPERATING MECHANISM FOR HIGH TENSION ELECTRIC SWITCH-GEAR:-

Operating mechanism for high tension electric switch gear comprising hydrauliccylinder means for reciprocating a rack, a pinion engaged with the rack for rotationthereby, and a three bar toggle linkage connected between said pinion and therotary stack of the switch for operating the switch; said mechanism beingcharacterized by its economy, compactness, foolproof operation, safety featuresand power.

ISOLATORS

• Elegant Design• Low watt loss• Switch disconnections, for manual operation.• Connection: 25 sq mm box type terminal on both side for cables.• Available in SP, DP, TP, and FP• Mounting: Clip on DIN 35 mm rail.• Can be mounted easily in any of the regular distribution boards.

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CONTROL AND INSTRUMENTATION CIRCLE

SWAS PACKAGE

Steam and Water Analysis System (SWAS) shall be furnished for continuousmonitoring and control of water and steam purity in the plant cycle and at otherimportant points as specified in this specification.

The sampling system shall obtain samples from steam and water system, whichshall be adequately conditioned and fed to analyzers for continuous analysis andprovide parallel facility for grab sampling as specified.

The analyzer outputs shall be used for providing -

a) Continuous monitoring of various parameters using indicator with anisolated analog outputs of 4-20mA, DC for each parameter for monitoring in plantmonitoring system.

b) RS-485 / Profibus output for diagnostics

c) Alarm for all significant parameters measurements, which exceed theirpermissible limits including those of sample conditioning system in the form ofpotential free contacts. The visual annunciation will be taken care of in maincontrol room. The alarm outputs should be terminated on the terminal blocksprovided in the junction box within the analyzer panel.

The offered system shall be complete with sample conditioning devices andmonitoring instruments (for temperature, pressure, flow & sample) and analyzersas well as all required accessories to provide a complete and integrated samplingand analysis system as per the intent and requirements of this specification. Sampleline diagrams shall be used to implement the design at system level. Vendor should

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be able to demonstrate the type test of sample conditioning system in his factory.As analyzer is the most important ingredient of SWAS, vendor should be able toprovide proofs of collaboration with internationally recognized analyzermanufacturer from Europe or USA. Vendor to also furnish performance lettersfrom reputed power companies like NTPC/BHEL. Non-compliance to any of thesecriteria automatically disqualifies the vendor.

All piping, tubing, fittings and other sample wetted parts in the sampling andanalyzing system shall be of type 316 stainless steel, except for those within theanalyzers, which will be as furnished by the manufacturer.

All SWAS system components and accessories shall be from the latest provenproduct range of qualified manufacturers. The SWAS package including analyzersshould be supplied by one approved systems vendor, who can supply the completeequipment. The vendor should have in-house capabilities to manufacture thepackage, such as TIG welding, NDT procedures, Hydrostatic testing upto 600 Bar,facilities for assembly & testing etc. The welding inside the SWAS panels shouldbe done by welders approved for high pressure welding. The welders should be1BR / ASTM approved.

Vendor to be able to provide proven track record in"Coa l based the rmal powerstations". For this, vendor must provide a list of SWAS supplies that are madeunder his own brand and also manufactured in his own manufacturing plant. Thesesupplies should have been made to Thermal Power Stations, which should be goodenough to qualify him as an experienced vendor for SWAS. Vendor should havesupplied such SWAS packages to minimum 10 Thermal power plants OR 20Combined Cycle power plants Non compliance to this criteria automaticallydisqualifies the vendor.

All sample piping from primary root valves on process fluid lines/equipment tobulk head of SWAS panel will be arranged by the buyer. The cooling water &necessary electrical supply upto the SWAS package will be arranged by the buyer.

SAMPLE CONDITIONING SYSTEM

Sample conditioning system shall be designed and constructed to receive andcondition all samples (listed in the enclosed Sample Stream Specification) asrequired by the respective analyzers connected to the sample streams.

Sample line to analyzer elements shall incorporate an anti-siphon design to preventpossibility of running dry because of a broken or plugged sample line

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SAMPE ISOLATION VALVES &BLOWDOWN VALVES

A) For High pressure & High Temperature Lines before primary sample cooling:All sample isolation valves & blowdown valves for sample pressures of 40Kg/Cm2 &/or above 200 Deg.C. above must be "Globe type with back seatarrangement", integral stellited seat and welded body/bonnet design. These Valvesmust be IBR approved & selected as per Valves Pressure Class- ANSI B16.34-1996, Material must be suitable to withstand this high pressure and hightemperature. Preformed pure graphite rings should be used as gland packingmaterial (graphoil ropes are not acceptable). The plug & spindle should be singlepiece & of non-rotating type. The plug should be guided throughout its travel. Thespindle should be roller burnished to ensure leakage free performance. For blowdown service, valve should be provided with control cone such that the throttlingarea gets separated from seating area, thus enhancing the life of the seat. Needlevalves / Instrument valves are not acceptable. Dilution of these specifications willdisqualify the vendor.

B) For Low pressure & Low Temperature Lines before secondary cooling:

For Low Pressure (i.e. below 40 Kg/Cm2) and temperature application. Needlevalves are acceptable suitable for these application. Material for these valve mustbe SS316.

SAMPLE COOLER (BOTH PRIMARY AND SECONDARY SAMPLECOOLERS)

All samples having a temperature in excess of 45° C shall be cooled by use ofsample cooler. The design of all sample coolers that handle live steam shall bevalidated by external authority in manufacturer's country.The sample cooler shalluse general service water (softened water) as cooling water. This cooling water istapped from general service water whose temperature may vary from 20 DegC to36 DegC. Cooling water pressure differential available for SWAS will beminimum 1.5 bars.

SAMPLE FILTERS

Sample particulars removal shall be accomplished by passing all samples throughfilters with type 316 stainless steel body. The filter design should allow theremoval of filter element without dis-assembling the Filter from the line. The filterelement shall be capable of retaining particles of 40 micron and larger. The filtershould be located before the pressure regulator.

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The filters in the secondary system shall be having blowdown arrangement for easeof cleaning of the filter element.

SPECIFICATIONS

Conductivity Analyzer

Description Specifications Vendor Response

Conductivity Sensor

Principle Resistive conductivitymeasurement

Measuring Ranges/ CellConstants

0 .0 -200 .0 pS/cm(k=0.01)

0- 2000pS/cm(k=0.1)

0.00 - 20.00 mS/cm (k=1)Relative accuracy ± 1% of full scale reading

(±2 % >500 mS/cm)

Temperature Sensor

Temperature -10.0 to + 125.0 °C (14.0 to257.0 °F)

Resolution 0 .1 °C/°F

Relative Accuracy ±0 .5 °C(± 1 .0 °F)

Sensor PT100

Temperature Compensation Auto / manual (reference at25 °C)

Set Point ControllerFunctions

Function (switchable) limit control

P/PI control (pulselength/pulse frequency)

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Integral time 0 to 999.9 minutes

Adjustable period withpulse length controller

0.5 to 20 sec.

Adjustable period withpulse frequency controller

60 to 120 pulses/min

Pickup / Dropout delay 0 to 2000 seconds

Wash cycle (If required-optional)

0.1 to 199.9 hours

Wash duration (If required-optional)

1 to 1999 seconds

Switching conductivityhysteresis

0 to 10 % of full scale

Contact outputs, controller 1 SPDT, 3 SPST relays

Switching voltage max. 250 VAC

Switching current max. 3A

Switching power max. 600 VA

Alarm Functions

Function (switchable) Latching / pulse

Pickup delay 0 to 2000 seconds

Switching voltage Max. 250 VAC

Switching current Max. 3A

Switching power Max. 600 VA

Display

LCD UV coat, backlit 14segments display withsymbols for statusinformation

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Backlight On/Off selectable with fourlevel of brightness control

ElectromagneticCompliance (EMC)Specifications

Emitted Interference EN 61326

Immunity to Interference EN 61326

Environmental Conditions

Ambient temperatureoperating range

0 to 40 °C

Maximum Relativehumidity

80% up to 31°C decreasinglinearly to 50% at 40°C

Power Supply

Input 80 to 250 VAC/DC 50/60Hz Approx. 10VA

Main Fuse 250 mA anti-surge, S504BUSSMANN

Pollution Degree 2

Transient Overvoltagecategory

II

Electrical Data andConnections

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Signal Output Two 0/4 to 20 mA outputsfor conductivity andtemperature, galvanicallyisolated.

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Digital communication Profibus DP

Load Max. 600 Q

Conductivity input Screw terminal

Connection terminal 5-pin, 9-pin, and 19-pinterminal blocks

Enclosure

Dimensions 175 x 96 x 96 mm (6.89 x3.78 x 3.78 inch)

Weight 700 g

Material ABS

Insulation IP 54 (front) / IP 40(housing)

I Cell And TransmittersDescription Specifications Vendor Response

pH Sensor

pH Range 2.00 to 12.00 pH

Resolution & Accuracy 0.01 pH & ± 0.01 pH

mV Range 0 to 100% or -1000 to 1000mV

Resolution & Accuracy 0.1% or 1 mV / ± 1 mV

Temperature -9.9 to 125 oC (15.0 to257.0 oF)

Resolution & Accuracy 0 .1 &±0.5 o C(± 1 .0 o F)

Sensor Pt 100

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Temperature Compensation Automatic (± 10 oC / ± 18oF offset adjustment) /

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Manual

Set-point And ControllerFunctions

Function Limit / ProportionalControl / ProportionalIntegral

(Pulse Length or PulseFrequency)

Integral time 999.9 minutes

Pickup / Dropout Delay 0 to 1999 seconds

Wash Cycle (If required-optional)

0.1 to 199.9 hours

Wash Duration (If required-optional)

1 to 1999 seconds

Switching pH Hysteresis 0.1 to 1 pH

Switching ORP Hysteresis 1 to 10 .0%/10 to 100 mV

Contact Outputs, Controller 1 SPDT; 3 SPST relays

SwitchingV oltage/Current/Power

Max 250 VAC / Max 3A /Max 600 VA

Alarm Functions

Function (switchable) Latching / pulse

Pickup delay 0 to 1999 seconds

SwitchingV oltage/Current/Power

Max 250 VAC / Max 3A /Max 600 VA

Display

LCD UV coat, backlit 14segments display with

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symbols for statusinformation

Backlight On/Off selection with fourlevel of brightness control

Emissions According to EN 50081-1

Susceptibility According to EN 50082-1

Environmental Conditions

Ambient Temp. OperatingRange

-10 to 50 oC (14 to 122 oF)

Rel. Humidity 10 to 95% (non-condensing)

Electrical Data AndConnections

Power requirements 80 to 250 V AC/DC

Frequency 48 to 62 Hz

Signal output Two /4 to 20 mA outputsfor pH/mv and temperature, galvanically isolated

Digital communication Profibus DP

Load Max.600 Q

pH / ORP Input BNC (1012 Impedance)

Connection terminal (1 x 3-pin; 1 x 9-pin & 1 x19-pin terminal blocks)

Main fuse 250 mA, anti-surge

Enclosure

Dimensions (W xHxD) 175 x 96 x 96 mm PanelMount

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Weight 7OOg (unit); 95Og (boxed)

Material ABS

Insulation IP 54 (front) , IP 4O(housing)

ATRS [Automatic Turbine Run Up System ]

INTRODUCTION

All control function related to turbine are realized by Microprocessor basedPROCONTROL ATRS System. This is based on user friendly programminglanguagePlO. The system is divided in three sub groups: -

1. SGC-OilOil pumps(AOP,EOP,JOP) interlocks, automatic & protn. Operationare realized in this group.

2. SGC-Conden. & Evac . : - CEP's & vacuum pump operation.

3. SGC-Turbine :- For automatic synchronization of machine to the grid.Procontrol requires serial data exchange confined to the electronic room(panels),process computer(monitoring) and control room.

HARDWAREThe data transmission is performed with two level serial bus system-Local Bus : - Local bus interconnects all input, output, and processing electronicmodules, which is part of station. Each local bus work independently from anyother local bus or Intra-Plant.

Intra - Plant Bus : - This bus interconnects its related local buses via coaxialcables. And through which Monitoring computer and diagnostic station connected.The local bus can be grouped together in the same panel or distributed in differentpanels. Each massage is cyclically transmitted over the local as well as intraplantbuses and transmission freq. Is selectable and can be every lO ms.

PROCONTROL has following basic type of electronic modules: -

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Individual Control modules : - These implemented to control, supervise, monitor,protect individual valves, pumps, fans etc. Modules equipped with amicroprocessor, built-in l/o and dedicated control entity to control element. Aserial l/o interface to the local bus to receive process signals required for interlaces& permissive logoc. Hardwired interface is also provided to control room. Modulesare- AS45, AS46, AS47.

Programmable Processor :- This modules used for automation and superimposedon the individual control modules and allows to build control, protection andalarms. Module is-PR05.

Input/Output modules :- Various modules for input/output capabilities andconnected to local bus. These modules can handle single, double throw contacts,thermocouple, RTD's, milliamp signals etc. or to provide milliamp, voltage,electronic contact output signals.

LOGIC: -SN1 Lub oil Pr V. Low

TURBINE

PROTACTIONSERVICE2.1kg/cm2

ALARM TRIP(2 out of Pr. Swth. Oprt.)

2 Cond vacuum V. Low -0.8-0.7kg/cm2 (2 out of 3 vac. Swth. Oprt.)

3 HPT Exhst Stm Tmp V. Hi 480-510

4 Axial Shift V. Hi +/-0.5mm. +/- 1.0mm (2 out of 3 Senser optd.)

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(2 out of 3 T/C Tmp. Rises)