of 42
/42
Dr. B. R. Ambedkar National Institute of Technology, Jalandhar Report on Summer Training [16 th June to 28 th July 2012]
| Date post: | 07-May-2015 |
| Category: |
Education |
| Author: | ranjeet-kumar |
| View: | 8,475 times |
| Download: | 3 times |
2. Ranjeet KumarIndustrial & ProductionEngineering09113039 [email protected] JalandharStudy of ElectricityGeneration ThroughSteam at PTPS 3. Power Consumption In India The energy sector holds the key in accelerating the economic growthof India. The energy demands for developing country like India keep oncontinuously growing. Energy is a driving force behind rapid economicgrowth of the country. India ranks tenth in the world in total energyconsumption. It is first requirement of energy to accelerate thedevelopment of the sector to meet its growth aspirations. The pattern of energy production put coal and oil again on top. Theseaccount for 65% of the entire generation. Renewable energy ranksbottom of the total production just before the Nuclear energy. Thedistribution of energy resource like hydro power is skewed towardsNorth-eastern states of the country as 70 % of the total hydro potentialis located in the Northern and North-eastern region.by [email protected] (N.I.T Jalandhar) 4. Figure of Power Consumption 5. Panki Thermal Power Station(PTPS),Kanpur[U.P] Panki Thermal Power Station is a Electricity Generation Station whereElectricity Generated through the steam operation on Turbine & Steam isGenerated by Coal Firing so it is a Typical Coal fired Electricity GenerationStation. It is Located about 16 Kms Away from Kanpur Railway Station ,was Startedwith two units(1st & 2nd) of 32 MW each.it was established in 1968. After Generating Power for about 28-29 years,2*32 MW units had completedtheir Rated Life So they were closed on 30th November 1995 & 18th April1997 respectively. So In 1976-77 ,Two Units (3rd & 4th of 2*110 MW each) Manufactured,Installed Bharat Heavy Electronics Ltd. These units were established in1976 & 1977 respectively. Unit 3rd & 4th have been derated to 105 MW each by the Central ElectricityAuthority(C.E.A) on 11th January 1990.So Presently there are two units (3rd & 4th of 105 MW each) working at PTPS. by [email protected] (N.I.TJalandhar) 6. About Steam Thermal Power Station Process:-A steam power plant is a power plant in which prime mover issteam driven. Water is heated ,turns into steam and spins asteam turbine(Impulse & reaction), which drives anelectrical generator. When the turbine turns, electricity isgenerated and given as output by the generator, which isthen supplied to the consumers through high-voltagepower lines.by [email protected] (N.I.T 7. Process Diagram at Steam Power Plantby [email protected] (N.I.T Jalandhar) 8. Fossil Fuel Power StationPreviously we discussed that steam is prime driven object in steampower plant so in the case we needed steam for power generation ;so thissteam is generated by boiling the water in boiler & this boiling is done byburning of Fuel.FOSSIL FUEL POWER STAION:-a fossil fuel power station is a power station that burns fossil fuels suchas coal ,natural gas or petroleum (oil) to produce electricity.Chemical EnergyHeat Energy MechanicalElectrical Fuel+oilFurnace Turbine Generatorby [email protected] (N.I.T Jalandhar) 9. Coal fired Steam Power Plant Coal Fired Power Station:-A coal Fired power station is that type of Fossil Fuel power station in which coal is used as a Fuel. In the Steam Power Plant There is a Separate Unit for Coal Handling System. There are basically Five main units of a thermal power plant:1. Coal Handling Plant (C.H.P)2. Water Treatment Plant (W.T.P)3. Boiler Maintenance Division (B.M.D)4. Turbine Maintenance Division (T.M.D)5. Generatorby [email protected] (N.I.T Jalandhar) 10. Coal Handling Plant-:COAL HANDLING & DELIVERING SYSTEM:-In a coal Based Thermal Power Plant , the initial process in the powergeneration is Coal Handling so in this article I will Discuss the overall ProcessCarried out a coal handling plant in a coal based thermal power generatingstation. The huge amount of coal is usually supplied through railways. A railwaysiding line is taken into the power station and the coal is delivered in thestorage yard. The coal is unloaded from the point of delivery by means ofwagon tippler. It is rack and pinion type. The coal is taken from the unloadingsite to dead storage by belt conveyors. The belt deliver the coal to 0 meterlevel & further moves to transfer point. The transfer points are used to transfercoal to the next belt. The belt elevates the coal to breaker house. It consists ofa rotary machine, which rotates the coal and separates the light dust from itthrough the action of gravity and transfer this dust to reject bin house throughbelt.by [email protected] (N.I.T Jalandhar) 11. Auxiliaries Of Coal Handling PlantThe belt further elevates the coal to the transfer point and it reaches the crusherthrough belt. In the crusher a high-speed 3-phase induction motor is used tocrush the coal to a size of 50mm so as to be suitable for milling system. Coal risesfrom crusher house and reaches the dead storage by passing through transferpoint.Equipment used in a coal handling plant1. Pull cord switchPull cord switch also known as Rope Operated Emergency Switch is used as safetyswitch to stop the conveyor belt in case of an emergency by pulling the Rope. Pullcord switch is mounted on the walkway side of the conveyor belt, Preferably atabout every 30 meters. when the rope is pulls from any side, the switch getsoperated. Unless and until the handle is reset manually position, the switch remainsin operated condition. NC contacts of all pull cord switches are wired in series andfurther connected to PLC. when any switch along the belt operates, the contactopens and conveyor is stopped.by [email protected] (N.I.T Jalandhar) 12. Figure of Pull cord switch & Belt weightierby [email protected] (N.I.T Jalandhar) 13. Auxiliaries Of Coal Handling Plant2. Vibrating feederThe coal stored in a huge hub is collected on the belt through vibrationscreated by the vibrating feeder.3. Flap gatesThese are used to channelize the route of coal through another belt in case theformer is broken or unhealthy. The flap gates open let the coal pass and ifclosed stop its movement.4. Magnetic separatorthese are used to separate the ferrous impurities from the coal.5. Metal detectorThese are detect the presence of any ferrous and non-ferrous metal in the coaland sends a signal to a relay which closes to seize the movement of belt untilthe metal is removed. It basically consists of a transmitter and a receiver.The transmitter consists of a high frequency oscillator, which produces a.by [email protected] (N.I.T Jalandhar) 14. Auxiliaries Of Coal Handling Plantoscillations of 1500 Hz at 15V. The receiver receives this frequency signal. Ifthere is any presence of metal in the coal. Then this frequency is disturbed anda tripping signal is send to relay to stop the conveyor belt6. Belt weightierIt is used to keep an account of the tension & support on the belt carrying coaland is moves accordingly to release tension on the belt.7. Reclaim hopperReclamation is a process of taking coal from the dead storage for preparationor further feeding to reclaim hoppers. This is accomplished by belt conveyorsby [email protected] (N.I.T Jalandhar) 15. Reclaim Hopperby [email protected] (N.I.T Jalandhar) 16. Steam Generation Process from CoalSTEAM GENERATION FROM COAL:-1. TipplersCoal from the coal wagons is unloaded in the coal handling plant. Thisunloading is done by the Tipplers. This coal is transported up to the raw coalbunkers with the help of conveyor belts.2.Coal CrushingAlthough coal can be burned in solid form on grates, it is more usual tobreak it up before feeding it to the combustion chamber. The treatmentdepends on the nature of the coal. Some coals lend themselves to beingground down to a very fine powder (called pulverized fuel (PF)) which isthen carried to the burners by a stream of air. Other coals are fed toimpact mills(Formally called Milling System) which use flails or hammers tobreak up the material before it is propelled to the burners by an air stream. Thetype of mill to be used on a particular plant will be determined by the processby [email protected] (N.I.T Jalandhar) 17. Preparation of Fuelengineers and it is the task of the control engineer to provide a system which isappropriate. To do this it is necessary to have some understanding of how therelevant type of mill operates.Various types of pulverized-fuel mill will be encountered, but two aremost commonly used:The Pressurized or vertical-spindle ball millhorizontal-tube millAT PTPS Vertical spindle ball mill is used.Vertical-spindle ball millsFigure shows the operating principle of a typical ball mill, such as theBabcock E mill. In this device, the coal that is discharged from thestorage hoppers is fed down a central chute onto a table where it is crushedby the crushing actions between the rollers and rotating tables rotating steelballs. Air is blown into the crushed coal and carries it, viaby [email protected] (N.I.T Jalandhar) 18. Preparation of Fueladjustable classifier blades, to the PFpipes that transport it to theburners. The air that carries the fineparticles of coal to the burners issupplied from a fan called a primary-air fan. This delivers air to the mill,whichtherefore operates under a pressurewhich is slightly positive with respectto the atmosphere outside. Becauseof this and because of its otherconstructionalfeatures, this type of mill is properlycalled a vertical-spindle,pressurized ball mill. by [email protected] (N.I.TJalandhar) 19. Air supply systems for Ball millsAs stated above, the crushed coal in a pressurized ball mill is propelled tothe burners by a stream of warm air for proper drying & obtaining a particulartemperature of coal. Figure shows the arrangementfor doing this: cool air and heated air are mixed to achieve the desired temperature. Primary Air FAN System for Ball Mill 20. Fuel Burning3.Grate- It is the platform in Furnace upon which Fuel is Burnt & it is made ofCast Iron Bars.The Bars are so arranged that air may pass on to the Fuel forcombustion.The area of the grate on which the fire rests in a coal or wood firedboiler is called Grate surface.4. FurnacesIt is a chamber formed by the space above the grate & below the boiler shell,inwhich combustion takes place. It is also called a fire Box.This crushed coal is taken away to the furnace through coal pipes with the helpof hot and cold air mixture from P.A Fan. P.A Fan takes atmospheric air, a partof which is sent to Air pre-heaters for heating while a part goes directly to themill for temperature control. Atmospheric air from F.D Fan is heated in the airheaters and sent to the furnace as combustion air.F.D(Force draught) Fan:-Force Draught Fan is main auxiliary of Furnacewhich Provides Oxygen for Proper Combustioning of Fuel.It Takes SuctionFrom Environment. It is an Axial Flow Fan.by [email protected] (N.I.T 21. by [email protected] (N.I.T Jalandhar) 22. Oil Handling System-:Oil Handling Plant:-In Thermal Power Station Fuel Oil play a vital role.Oil burners besides initiallighting up are also used to provide effective ignition of the coal associated withP.F Burners and to stabilize the flame .The Burners can provide enough heat tocarry on boiling operation of the boilers for the initial starting period. It canProvide 10-15% of the maximum load. At Lean Period or when it is desired toRun the Boilers at OFF Load Condition oil Burners are used.Fuel oil used in Power Stations Are:-# Heavy Furnace Oil (H.F.O)# Light Diesel Oil (L.D.O)# High Speed Diesel Oil (H.S.D)# Low Sulphur High Stock Oil (L.S.H.S)At Panki Thermal Power Station L.D.O is used as Fuel Oilby [email protected] (N.I.T Jalandhar) 23. Water Treatment Plant (W.T.P)The Water Treatment plant is required at the water from canal cant be directly Used inBoiler for Thermal Electricity Generator water is converted into steam at High Pressure &It is allowed to force Turbine Rotated and the electricity is Generated. Therefore water isthe basic requirement to the thermal Power plant. Generally in the Thermal Power PlantIs Employed to Refine the Water.Necessity of Water Treatment:-Natural Water Contains Solid,Liquid & Gasseous Impurities and Therefore this water cantBe used for Generation of Steam in the Boiler ,The different Effect introduced due to useOf Unrated Water in the boiler.So the water impurities should be removed before its usedas a stream.The following procedure is used in WTP for minimizing the hardness &removing the impurities:-Flocculate Plant:-Here Alum is added is added to water to PrecipitateDust Particles In Water.Aluminium in Alumneutralizes Charge Dust Particle & this gives Resultto a heavy Complex Compound Which is settledby [email protected] (N.I.T 24. Auxiliaries of W.T.Pdown. Bleaching Powder & limestone along with chloride is also added in thisflocculation Tank to remove temporary hardness & chloride also removesBacteria & Organic matter. This is Called flocculate plant because ,all the mixing and processing isdone In flocculation plant where flocculation Mechanism is also happens.Sand Filter-These Stages of sand filter are putt across the flow so as to remove otherSuspended Particle, If any.Activated Carbon filter-This Filter is employed for removal of Bacteria and organic material. Hereanthracite(Coal) is uses for Filter.by [email protected] (N.I.T Jalandhar) 25. Auxiliaries of W.T.PCation Exchanger-At this stage ions are observed by ion exchnanger method,HCl and negativeresin are principle ingredient of this chemical filterAnion Exchanger:-Here Negative Ions are observed by Carefully Formulated by positive resin.Mixed Bed Exchanger:-Here Remaining a negative ion is removed that is extracted through resin.The D.M(De mineralized) water is now ready which has some properties-Conductivity-0.03 to 0.5 (micro/cm2)PH-6.5Hardness-NILby [email protected] (N.I.T Jalandhar) 26. Diagram of W.T.P at PTPS 27. Boiler Maintenance Division (B.M.D)Boiler:-Boiler is an apparatus to produce Steam. Thermal energy Released byCombustion of Fuel is Transferred to water ,Which Vaporizes and getsconverted water into steam at the desired temperature and pressure.It is about52 meter from the ground level.About its Design The boiler is a rectangularfurnace about 50 ft (15 m) on aside and 130 ft (40 m) tall. Its walls are made ofa web of high pressure steel tubes about 2.3 inches(60 mm) in diameter. Pulverized coal is air-blown into the furnace from fuelnozzles at the four corners and it rapidly burns, Forminga large fireball at the center. The thermal radiation of the fireball heats the waterthat circulates through the boiler tubes near the boiler perimeter. The watercirculation rate in the boiler is three to four times the throughput and is typicallydriven by pumps. As the water in the boiler circulates it absorbs heat andchanges into steam at 7000F (3700C)and 3,200psi (22.1MPa). It is separatedfrom the water inside a drum at the top of the furnace. The saturated steam isintroduced into superheat pendant. by [email protected] (N.I.T 28. B.M.D & Its Supporting Auxiliariestubes that hang in the hottest part of the combustion gases as they exit thefurnace. Here the steam is superheated to 1,000F (540 C) to prepare it for theturbine. The steam generating boiler has to produce steam at thehigh purity, pressure and temperature required for the steam turbinethat drives the electrical generator. The generator includes theeconomizer,The Boiler ShellSettingGrateThe furnace with its steam generating tubesNecessary safety valves are located at suitable points to avoidexcessive boiler pressure. The air and flue gas path equipment include:Forced draft (FD) fanAir preheater(APH)by [email protected] (N.I.T Jalandhar) 29. B.M.D & Its Supporting Auxiliaries boiler furnace induced draft (ID) fan Fly ash collectors (electrostatic precipitator or bag house) and The flue gas stack.The Steam produced is used for Producing Mechanical work by expanding it in steam engine or steam turbine.According the Process Boiler is of two type-1.Water Tube Boiler-In water Tube boilers,Water cIrculates through the tubes and hot products of Combustion Flow over These tubes.2.Fire Tube Boiler In this fire flows in the tubes & tubes is surrounded by water,Fire tube boilers have low Initial cost in compare to Water Tube Boiler.At PTPS Water Tube Boilers Are Used. Boilers are also called Steam Generatorby [email protected] (N.I.T Jalandhar) 30. Boiler 31. B.M.D & Its Supporting AuxiliariesBoiler Shell or Boiler Drum:-The Shell or drum Consist of one or moreSteel Plates bent Into Cylinderical Form land Riveted or welded together.Theshell end are closed with the end plates.Its second or down plate made morethicker than upper because all load applied on this.It is the main drum whichReceived D.M Water from Boiler Feed Pump Passing through High PressureHeater & Economizer at a operating Pressure of 183kg/cm2 From BoilerDrum.The Water Runs through the tubes.These Tubes are known as downcomers.Setting- The Primary Function of setting is to continue Heat to the Boiler bythe Passes of gases taking From FD Fan .It is made from Brickwork.Grate- It is the platform in Furnace upon which Fuel is Burnt & it is made ofCast Iron Bars.The Bars are so arranged that air may pass on to the Fuel forcombustion.The area of the grate on which the fire rests in a coal or wood firedboiler is called Grate surface.Furnaces-It is a chamber formed by the space above the grate & below theby [email protected] (N.I.T Jalandhar) 32. External View of Boiler at PTPSboiler shell,in which combustion takes place. It is also called a fire Box.by [email protected] (N.I.T Jalandhar) 33. B.M.D & Its Supporting AuxiliariesMountings-The Items Such as Stop Valve ,Safety valve, Water level Gauges,Fusible Plug,Blow off cock ,Pressure Gauges,Water level Indicator etc. are themountings and a boiler cant work safely without these.Path away Accessories or Integral Part of Boilers:-Economizer:-Economizer is an important boiler accessory.The work ofEconomizer is preheating of Feed water of boiler and to less Fuel consumptionFurnace. Preheating of feed Water is done by Flue Gases which is comes fromafter burning of Fuel in the Combustion Chamber. The Temperature of FeedWater at inlet of economizer is in Range of 160-1800C And after Leaving it,It becomes 2100C.It is located in Rear Side of Boiler.Rotating Air Pre Heater:- The Purpose of Air Preheater is to Recover heatof the Flue Gases Which is at a Considerably High as PA Fans Temperature. ItRotates at the Speed of 176 rpm. The Heat of the flue gases is absorbed byHeating Surface of air pre heaters and then transfer to the cool air comingFrom P.A Fans.by [email protected] (N.I.T Jalandhar) 34. B.M.D & Its Supporting Auxiliaries LPH(Low Pressure Heater):-it takes Extraction from Turbine & gives theseExtraction to Condensate Water Cycle for PreHeating of this water.It isSituated at 4meter level on Turbine Side. HPH(High Pressure Heater):- Its work same as LPH to Preheat of Feedwater by bleeding of Turbine. Dearator:-Work of Dearator is to Dearate of Water means to RemoveDissolve Gases from DM water & to Give Proper Suction To Boiler FeedPump.It is Situated at 27meter level in Boiler side. Boiler Feed Pump:-Its work is to take suction from dearator and give it toBoiler Drum on High Pressure(183Kg/cm2).Cycle of Dearator to boiler drumis called Feed Water Cycle.It is situated at 0 meter level on Turbine side. F.D(Force draught) Fan:-Force Draught Fan is main auxiliary of Furnacewhich Provides Oxygen for Proper Combustioning of Fuel. It Takes SuctionFrom Environment. It is an Axial Flow Fan.by [email protected] (N.I.T Jalandhar) 35. B.M.D & Its Supporting AuxiliariesID fan(Induced Draft Fan):-basically pulls out flue gas from the furnace ofboiler. It is located between dust precipitators(ESPs) and Chimney. Obviously ithandles hot air/dust. Whereas, FD fan(Forced Draft Fan)supplies the requiredair into the furnace for combustion of fuel. It handles air at normal temperature.The capacity/power rating of ID fan will be more than that of FD fan.Chimney:-When Coal burns in Furnace then Produce Smoke, Flew Gaseswhich content NO,SO2,CO,C etc. that ash is send in to Electro Staticprecipitation and ash comes out with water but some Ash is sucked by I.D fanwhich send into chimney with the smoke so the some which is passing throughChimney is Black.Super Heater:-The Function of a super heater is to Increase the Temperatureof Steam above Its Saturation point.The Super heater is very importantaccessory of a Boiler & used in both in Fire Tube & Water Tube Boiler.by [email protected] (N.I.T Jalandhar) 36. Turbine Maintenance Division(T.M.D) Steam TurbineSteam turbines are used in all of our major coal fired power stations todrive the generators or alternators, which produce electricity. The turbines themselves are driven by steam generated in Boilers or Steam Generators as they are sometimes called.Energy in the steam after it leaves the boiler isconverted into rotational energy as it passes through the turbine. The turbine normally consists of several stages with each stage consisting of a stationary blade (or nozzle) and a rotating blade. Stationary blades convert the potentialenergy of the steam (temperature and pressure) into kinetic energy (velocity)And direct the flow onto the rotating blades. The rotating blades convert the kinetic energy into forces, caused by pressure drop, which results in the rotation of the turbine shaft. The turbine shaft is connected to a generator, whichproduces the electrical energy. The rotational speed is 3000 rpm for by [email protected] (N.I.T 37. T.M.DIn a typical larger power stations, the steam turbines are split into threeseparate stages, the first being the High Pressure (HP), the second theIntermediate Pressure (IP) and the third the Low Pressure (LP) stage, wherehigh, intermediate and low describe the pressure of the steam. After the steamhas passed through the HP stage, it is returned to the boiler to be re-heatedto its original temperature although the pressure remains greatly reduced. Thereheated steam then passes through the IP stage and finally to the LP stage ofthe turbine. A distinction is made between "impulse" and "reaction turbinedesigns based on the relative pressure drop across the stage. There are twomeasures for pressure drop, the pressure ratio and the percent reaction.Pressure ratio is the pressure at the stage exit divided by the pressure at thestage entrance. Reaction is the percentage is entropic enthalpy drop across therotating blade or bucket compared to the total stage enthalpy drop. Somemanufacturers utilize percent pressure drop across stage to define reaction.by [email protected] (N.I.T Jalandhar) 38. Steam PropertiesAt High Pressure (H.P) Turbine:-Entrance Pressure-5350C-5400CEntrance Temperature-130Kg/cm2Exit Pressure - 26Kg/cm2Exit Temperature-3400CAt Intermediate Pressure(I.P) Turbine:-Entrance Pressure-24Kg/cm2Entrance Temperature-5350CExit Pressure-1.02 Kg/cm2Exit Temperature-1400Cby [email protected] (N.I.T Jalandhar) 39. Steam Turbineby [email protected] (N.I.T Jalandhar) 40. GeneratorGenerator:-An electric Generator is a machine which converts Mechanical Energy (orPower) into Electrical Energy. This Energy Conversion is based on the principleof the production of dynamically induced e.m.f is Produced in it according tofaradays law, Whenever a conductor is moving in a magnetic Field then it cutsMagnetic Flux and there were an E.M.F(Electro magnetic Force) Produced,which is Called Induced E.M.F.e=N*d/dtby [email protected] (N.I.T Jalandhar) 41. Overall Process 42. Thank You !by [email protected] (N.I.T Jalandhar)
