boiler design basics.pdf
TRANSCRIPT
An Introduction to BoilerDesign Basics
JC Foucher
Feb 10, 2003Feb 10, 2003
Date of last change Reference/Name of Presentation/SN 2
Boiler design basicsSummary
HistoryThermodynamics for beginnersBoiler designUtilily versus Industrial boilersBoiler Construction, Examples, and Troubles
Date of last change Reference/Name of Presentation/SN 3
Boiler design basicsSummary
HistoryThermodynamics for beginnersBoiler designUtilily versus Industrial boilersBoiler Construction, Examples, and Troubles
Date of last change Reference/Name of Presentation/SN 4
History : Steam as a resource
The most significant series of eventsshaping today’s world is the late 17thcentury industrial revolution.
However, the first steam reaction turbine,illutrated here, has been invented in 200 BCby Hero from Greece.
Steam Technology is an old invention itsfuture is still brilliant, based on the samefundamentals :
- GENERATE HEAT- TRANSFER THE HEAT to WATER- PRODUCE STEAM and- CONVERT TO ENERGY
Source : ALSTOM Indonesia Boiler Seminar, April 2002
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History :First Application of Steam Power
Steam Industries develop afterinventors designed safe andefficient steam devices useful toman activities : Alexandro Brancafrom Italy invented in the 16thcentury a device, illustrated here,which marked the beginning ofSteam Turbine Development.
It was used for milling wheat grainseffortlessly.
Source : ALSTOM Indonesia Boiler Seminar, April 2002
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Modern Use of Steam Power
Power GenerationIndustrial ProcessesSea and land transportationDistrict HeatingOther special uses
Source : ALSTOM Indonesia Boiler Seminar, April 2002
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A Typical Power Station
Source : ALSTOM Indonesia Boiler Seminar, April 2002
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Boiler design basicsSummary
HistoryThermodynamics for beginnersBoiler designUtilily versus Industrial boilersBoiler Construction, Examples, andTroubles
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Thermodynamics for beginners - 1
A vessel is filled with an amount of water( ) and warmed at constant pressureup to boilinga continuing supply of heat changeswater phase from liquid to gas (steam),the temperature remains constantresult : a steam at temp. Tp, pressurePp, volume Vp and energy stored asinternal heat or enthalpy Qpone m3 of water is transformed undersuch conditions into 1700 m3 of steam
Source : ALSTOM Indonesia Boiler Seminar, April 2002
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Thermodynamics for beginners - 2
A vessel is filled with the same water amount( ) and warmed at constant volume up toboilinga continuing supply of heat changes waterphase from liquid to gas (steam),result :
– steam temperature Tv >Tp,– pressure Pv > Pp,– Vv =Vp volume unchanged– energy stored as internal heat or enthalpy Qv > Qp
Source : ALSTOM Indonesia Boiler Seminar, April 2002
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Thermodynamics for beginners - 3
Steam generation is a phase change or water from liquidto gas, thanks to a continuous supply of heat,
the higher both pressure and temperature are, the higheris the energy stored in the steam,
the steam turbine purpose is to convert this thermalenergy into rotational mechanical energy
the purpose of the generator is to convert this rotationalmechanical energy into electric energy
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Thermodynamics for beginners - 4
From F to A to B– liquid water warm-up
B : evaporation beginsB to C :– mixture of water
(decreasing) andsteam (increasing)called saturatedsteam
From F to A to B– liquid water warm-up
B : evaporation beginsB to C :– mixture of water
(decreasing) andsteam (increasing)called saturatedsteam
The Water-Steam Cycle inside the boiler
Temp.
Entropy
A
B C
F
K
Source : J. Goalvoueden in Les Techniques de l ’Ingénieur, B 124
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C : evaporationcompleted, steamstill saturatedC to D– steam is
superheatedD– superheated
steam sent toturbine
C : evaporationcompleted, steamstill saturatedC to D– steam is
superheatedD– superheated
steam sent toturbine
Thermodynamics for beginners - 5
The Water-Steam Cycle inside the boiler (cont)
Temp.
Entropy
A
B C
D
F
K
Source : J. Goalvoueden in Les Techniques de l ’Ingénieur, B 124
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D to E– expansion in the
steam turbineE to F
– steam iscondensed andcooled in thecondenser
F– water available for
a new cycle
D to E– expansion in the
steam turbineE to F
– steam iscondensed andcooled in thecondenser
F– water available for
a new cycle
The Water-Steam Cycle outside the boiler
Thermodynamics for beginners - 6
Temp.
Entropy
A
B C
D
F
K
E
Source : J. Goalvoueden in Les Techniques de l ’Ingénieur, B 124
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Thermodynamics for beginners - 7
Temp.
Entropy
A
B C
D
F
K
E
Single Rankine Reheat Steam Cycle
Source : J. Goalvoueden in Les Techniques de l ’Ingénieur, B 124
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Thermodynamics for beginners - 8
Temp.
Entropy
A
BC
D
F
K
L
I
K D to I– expansion in the
HP steam turbineI to K– steam returns to
the boiler and isreheated
K to L– expansion in the
IP/LP steamturbine
D to I– expansion in the
HP steam turbineI to K– steam returns to
the boiler and isreheated
K to L– expansion in the
IP/LP steamturbine
Double Reheat Steam Cycle
Source : J. Goalvoueden in Les Techniques de l ’Ingénieur, B 124
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Flows and Heat Exchangein the Boiler
Source : Combustion, Fossil Power J.G. Singer 1991, ch 5 p 7 fig 2
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The Complete Water-Steam Cycle
Source : ALSTOM Indonesia Boiler Seminar, April 2002
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Boiler design basicsSummary
HistoryThermodynamics for beginnersBoiler designUtilily versus Industrial boilersBoiler Construction, Examples, andTroubles
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Boiler design basicsSummary
Boiler design– various boiler designs– type of operation– fuels, solid, liquid, gaseous– firing systems– steam water circulation
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Various Boiler Designs
Intended use industrial, power generation,
construction shop or field assembled
firing system grate, suspension, fluidized bed
boiler arrangement hanged or bottom supported
water circulation natural, controlled, forced
fuel solid, liquid, gas, waste heat
Based on :
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Boiler design basicsSummary
Boiler design– various boiler designs– type of operation– fuels, solid, liquid, gaseous– firing systems– steam water circulation
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Utility plants and boilers :three types of operation
Base load : 100% capacity 24/7/365– highest capacities (up to 1000 MWe), high efficiency– no load-follow requirement
Peak load– ultra-fast startup time, suitable for «golden hours»– competition with open cycle gas turbines– a few hundred hours per year– no high efficiency requirement
Intermediate load– in between, high load-follow capability
- customized design versus type of operation -- customized design versus type of operation -
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Boiler design basicsSummary
Boiler design– various boiler designs– type of operation– fuels, solid, liquid, gaseous– firing systems– steam water circulation
Note : this seminar is targeted to an area where use of coal is limited.Consequently, the information provided for coal firing is purposedly limited.
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Solid Fuels, Fossil
Coal (from 15 to 30 MJ/Kg)
Source : Combustion, Fossil Power J.G. Singer 1991, ch 2
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Solid Fuels, Non-Fossil
Coke– fused solid residue from chemical processes involving
coal or oilPetroleum coke (petcoke)
– petrochem byproduct (32-36 MJ/Kg, 3-6% sulfur)Wood (20 MJ/Kg)Bark (mainly from paper mills)Food processing wastesMunicipal and industrial refuses (7 to 15 MJ/Kg)
Source : Combustion, Fossil Power J.G. Singer 1991, ch 2
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Liquid Fuels
Crude petroleum– high amount of volatile compounds
Fuel oilFuel Oil GradeFuel Oil Grade
TypeType
ColorColorMJ/KgMJ/Kg
Sulfur content,%Sulfur content,%Atomizing tempAtomizing temp
FO n°1FO n°1
DistillateKéroseneDistillateKérosene
LightLight
46,446,4
0,10,1
AmbientAmbient
FO n°2FO n°2
DistillateDistillate
AmberAmber
45,545,5
0,4 - 0,70,4 - 0,7
AmbientAmbient
FO n°4FO n°4
Very LightResidual
Very LightResidual
BlackBlack
43,443,4
0,4 - 1,50,4 - 1,5
-4°C min-4°C min
FO n°5FO n°5
LightResidual
LightResidual
BlackBlack
43,443,4
2.02.0
50°C50°C
FO n°6FO n°6
ResidualResidual
BlackBlack
42,542,5
2.82.8
93°C93°C
1 lb/USgal x 119.8 = Kg/m31 BTU/Usgal x 278.72 = KJ/m3KJ/m3 / (volumic mass Kg/m3) =KJ/Kg- Oil fired boilers can be converted to crude firing -
Source : Combustion, Fossil Power J.G. Singer 1991, ch 2
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Gaseous Fuels
Natural gasLiquefied Petroleum gas (LPG)Refinery and oil gas,Gas from steel processing : coke oven and blastfurnace gas
1 lb/USgal x 119.8 = Kg/m31 BTU/Usgal x 278.72 = KJ/m3KJ/m3 / (volumic mass Kg/m3) =KJ/Kg- Oil fired boilers can be converted to gas firing -
GasGas PropanePropane ButaneButane Natural GasNatural Gas LPGLPG
C3H8C3H8 C4H10C4H10 mixmix mixmix
MJ/KgMJ/Kg 5050 4646 4747 4545
Source : Combustion, Fossil Power J.G. Singer 1991, ch 2
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Fuels, Typical Problems
Degradation of fuel quality with timeExhaustion of fuel resource with time, leading tofuel switchingHigh quality fuel exported, low quality burneddomesticallyCost increase, leading to fuel switchingNOx generation propertiesSulfur content, inducing acid dew point corrosionParticulates content
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Boiler design basicsSummary
Boiler design– various boiler designs– type of operation– fuels, solid, liquid, gaseous– firing systems– steam water circulation
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Firing systems
Firing on a travelling grate– suitable to un-pulverized solid fuels
Suspended firing– suitable to pulverized coal, liquid and gaseous fuels
Fluidized bed combustion– suitable to coarse pulverized solid low grade fuels
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Firing solid fuelson a travelling grate
Solid crushed fuel
Drive shaft
Air Ash
Air Ash
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Suspension firing
Solid pulverized fuels– solid fuel ground to the
fineness of face powderLiquid fuelsGases
Solid pulverized fuels– solid fuel ground to the
fineness of face powderLiquid fuelsGases
Air + pulverizedfuel
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Fluidized Bed Combustion,principle
Ability to burn low-gradefuelsFuel flexibilityImmune to ash propertiesNOx limited productionIn-situ SOx capture
Ability to burn low-gradefuelsFuel flexibilityImmune to ash propertiesNOx limited productionIn-situ SOx capture
TubeBundle
FluidizedBed
Fluegas
Fuel & sorbent
Air
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Fluidized Bed Combustion,Types
BubblingFluidized Bed
gas
Fuel & sorbent
Air Ash
gas
CirculatingFluidized Bed
Fuel & sorbent
Air
Air Ash
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Boiler design basicsSummary
Boiler design– various boiler designs– type of operation– fuels, solid, liquid, gaseous– firing systems– steam water circulation
Date of last change Reference/Name of Presentation/SN 37
The Natural Circulation Boiler
No circulation pumpcirculation driven bydensity differencesbetween water andsteam/water mixturepressure increasedetrimental tocirculation : lowpressure boilers only
No circulation pumpcirculation driven bydensity differencesbetween water andsteam/water mixturepressure increasedetrimental tocirculation : lowpressure boilers only
Date of last change Reference/Name of Presentation/SN 38
Controlled Circulation boiler
circulation pumpallow higher pressurelevels and hence,capacitiesbetter load followcapabilitymore complexauxiliary consumptiondrum thicknessincrease
circulation pumpallow higher pressurelevels and hence,capacitiesbetter load followcapabilitymore complexauxiliary consumptiondrum thicknessincrease
Date of last change Reference/Name of Presentation/SN 39
Forced Circulation Boiler
No drumonce-through circulationfast start-up/shutdowninvented by Sulzer ofSwitzerland, now withinALSTOMthe « tower » type boiler
No drumonce-through circulationfast start-up/shutdowninvented by Sulzer ofSwitzerland, now withinALSTOMthe « tower » type boiler
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Evaporator Design
Goal : avoid anydeparture fromsafe nucleateboiling (DNB)as tube integrityis therefore atrisk
Goal : avoid anydeparture fromsafe nucleateboiling (DNB)as tube integrityis therefore atrisk
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Steam - Water Separation :The Drum
Primaryseparator
Secondaryseparator
Tertiary separators
Water/steammixture from
evaporator
Pure WaterDowncomers
Feedwaterinlet
Dry saturated steam towards superheaters
Water level
Source : Combustion, Fossil Power J.G. Singer 1991, ch 7 p 16 fig 7
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Boiler design basicsSummary
HistoryThermodynamics for beginnersBoiler designUtilily versus Industrial boilersBoiler Construction, , Examples,and Troubles
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Utility vs Industrial boilers
Except size, no basic design difference betweenboth : a boiler is quite always (1) a combination of afurnace where the combustion occurs, and,downstream, a series of heat exchangers wherethe combustion heat is transferred to the water andsteam
Utility boilers, whose final purpose is electricitygeneration, must provide high reliable service, andshow good efficiency
1 - Except HRSGs
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Utility vs Industrial boilers (+)
Industrial boilers (whose final purpose is notelectricity generation) must often show a greatflexibility to meet quick load swings
Both uses are mixed in combined heat-and-power stations such as desalination plants, pulp& paper, petrochemical, steel processing, foodindustries
1 - Except HRSGs
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Shop vs site boiler construction
Shop construction– integrated package with preassembled auxiliaries– shipping routes from shop to site must be carefully
investigated– all construction by shop staff– option limited to small boiler
Site construction– shop-assembled components easy to ship– significant amount of work by local staff– option required for large utility boilers– strong site construction supervision
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Typical boiler specification
Boiler– Information related to the water and steam generating
equipment and unit designationFurnace– Dimensions / Total Volume
Superheater and reheater design– mono/multistage, layout, pendant/panel/platen
Air Heater– regenerative bi/tri sectors, cold end plate material
Economizer– tube type, finned or plain,
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Typical boiler specification (+)
Fuel specificationCombustion system– fuel preparation and handling, burners type
Operating Conditions– Controll point, lowest load ensuring normal steam temp– Maximum Continuous Rating (MCR)– Guaranteed load, base for overall unit efficiency
guarantee
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Typical boiler specification (++)
Boiler Capacity– steam flow rate at MCR– control load : steam temp achieved and controlled
Boiler Efficiency– Efficiency of xx% means that xx% of the heat supplied
by the fuel is transferred to the water / steam mixture,and 100 - xx% is lost
– 100% efficiency is not achievable in a cost effective way
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Boiler design basicsSummary
HistoryThermodynamics for beginnersBoiler designUtilily versus Industrial boilersBoiler Construction, Examples, and Troubles
Date of last change Reference/Name of Presentation/SN 50
Small / Medium size Boilers
Bottom supportedCan be shopconstructed (packageboilers)All heat furnace andheat exchangers rest ongroundthermal expansionlateral and upwardsrestrainedsensitive to earthquakes
Date of last change Reference/Name of Presentation/SN 51
Small / Medium size BoilersThe ALSTOM« D » Package Boiler
– compact– small capacity– 100% shop assembled– shipped on train or barges– fast erection
Date of last change Reference/Name of Presentation/SN 52
Small / Medium size Boilers
The ALSTOM/CE« D » type VPpackage boiler
– compact size– small capacity– 100% shop
assembled– shipped on train or
barges– fast erection
Date of last change Reference/Name of Presentation/SN 53
Small / Medium size Boilers
The ALSTOM/CE« VU60 » D typepackage boilerup to 270 t/hr(approx 90 MWepower)
Date of last change Reference/Name of Presentation/SN 54
Large size Boilers
Large Utility boilersTop supported/hangedAll heat furnace andheat exchangershanged from the topAllow easy thermalexpansion both lateraland downwardsresistant to earthquakesfootprint minimized
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GermanyNiederaussem K1012 MWe (gross)ligniteonce-through forcedcirculation supercriticaloperation: 2002Fuel: ligniteSteam 274 bar, 580°C/600°C94.4 % efficiency
Large size Boilers
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ligniteCirculatingFluidized Bedoperation: 2002Steam 184 bar,541°CBechtel
Large size Boilers
USARed Hills 2 x 250 MWe
- Largest lignite-fired CFB in the world -- Largest lignite-fired CFB in the world -
Date of last change Reference/Name of Presentation/SN 57
Shoaiba, 3 x 350MWe in Saudi ArabiaOil-fired2 pass - subcriticalControlled CirculationOperation: 2002Fuel: Oil & gasSteam 182 bar,540°C/540°C
Menu Sub
Large size Boilers
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EgyptSuez 3 & 4 (and Aboukir)2 x 325 MWeOil or gas-fireddrum boiler, 2 coupledpass ControlledCirculationOperation: 1987Fuel: Oil & gasSteam 181 bar,541°C/541°C
Large size Boilers
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Large size Boilers
SH
SH
RHRH
RH
EC0
Vaporizer
Heat Exchangers Arrangement
Date of last change Reference/Name of Presentation/SN 60
Large size boilerGlossary, top
Pressure-partsupport steel Hanger rods
Rearpasssteam-cooledroof
Finishing(High temp)Superheateror reheater
Buckstays
ConvectionSuperheateror reheater
Structuralsteel framing
Furnacesteam-cooledroof
Drum U bolts
Riser tubesSteam drum
Superheaterpanels
Superheateror reheater
platensRadiant wall
reheater
Reheaterinlet header
Source : Combustion, Fossil Power J.G. Singer 1991, ch 7 p 21 fig 11
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Large size boilerGlossary, middle
ConvectionSuperheateror reheater
Radiant wallreheater
Reheaterinlet header
Economiser
Furnace rearwallEconomiserinletWindboxEconomiserash hoppers
Ljungstrom®RegenerativeAir heater
Furnaceside wallFurnace
front wall
Downcomers
Burners
Boiler watercirculating
pumpSource : Combustion, Fossil Power J.G. Singer 1991, ch 7 p 21 fig 11
Date of last change Reference/Name of Presentation/SN 62
Large size boilerGlossary, bottom
Ljungstrom®RegenerativeAir heater
Boiler watercirculating
pump
Forceddraft fans
Primaryair fans
Bottom-ashhopper
Lower waterwallring header
Source : Combustion, Fossil Power J.G. Singer 1991, ch 7 p 21 fig 11
Date of last change Reference/Name of Presentation/SN 63
Boiler Construction : furnace
Tube wall
Tube wall (membrane)Insulation
lagging
Corner closure plate
HorizontalBuckstayPourable
Insulation
Insulationpins
Galvanizedhex mesh
Ribbedouter casing
Mineralliner fibredoublelayer
Date of last change Reference/Name of Presentation/SN 64
Boiler Construction :Combustion Area
Two firing types– tangential firing
– Front/wall firing
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Boiler Furnace : T / front firing
Tangential firing
Burners are located in the furnace anglesNo individual flames but a rotating fireball
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Boiler furnace : T / front firing
Burners are located onone furnace wall or twofacing walls.
Flames stay individual
Front firing
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Tangential and wall firedVU 60 industrial boilers
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Combustion System Issues
Incomplete/bad combustion : yellow flame, blacksmokeLack of combustion air, insufficient excess airFlame too long (front firing)Flame too close from the wall (T firing)Flame instability at low loadsPoor fuel oil pulverizationSuperheater / reheater burned on gas firingEmissions of NOx, SOx and particulates
Date of last change Reference/Name of Presentation/SN 70
Boiler Tube issues
Tube cleanlinessTube corrosion by combustionbyproductsTube overheatingTube pittingHydrogen-induced tubeembrittlementTube ductile gouging
Date of last change Reference/Name of Presentation/SN 71
Heat Transfer and Tube Cleanliness
• Loss in the tube wall only
• Loss in the tube wall• Loss in external deposits
• Loss in internal deposits
Energy Loss, clean tube
Energy Loss, fouled tube
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Heat Transfer and Tube Cleanliness
Date of last change Reference/Name of Presentation/SN 73
Remove externaldeposits
by sootblowing
Avoid internal deposits bywater treatment; remove
by acid cleaning
Heat Transfer and Tube Cleanliness
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Corrosion of Heat Exchangersby Combustion Byproducts
High temperature corrosion in superheaters andreheaters– promoted by sodium and vanadium compounds– sensitive if metal temp. above 600°C
Medium temp. Corrosion in evaporators– fixed through combustion system adjustment
Low temp. Corrosion in cold areas– promoted by sulfur, which turns into sulfuric acid
below dew point : keep temperature above 150°C
Date of last change Reference/Name of Presentation/SN 75
Tube failures - Overheating
Cross section of a tube exposedto short time overheatingCause : often DNB excursion
Long time overheating failure
Short time overheating failure
Long time overheating failure
Date of last change Reference/Name of Presentation/SN 76
Tube failures - Pitting
Electromechanical corrosion
Fix : appropriate water chemistry
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Tube failures - Others
Ductile gouging :irregular wastage of the tubemeteal beneath a porous deposit
Fix : appropriate water chemistry
Hydrogen-inducedtube burst : occursbeneath a relativelydense deposit
Fix : appropriate waterchemistry
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Boiler Construction : Drum
Water/steammixture from
evaporator
Dry saturated steam towards superheatersFeedwater
Date of last change Reference/Name of Presentation/SN 79
Troubles associated to drums
Loss of level gaugeswater level controllers out of servicecorrosionmoisture carry-over in the steamsafety valves leakingleaks of roll-expanded evaporatortubesplugging of evaporator tubes
Date of last change Reference/Name of Presentation/SN 80
Boiler Auxiliary : Ljungstrom®Regenerative Air Heater
Hot flue gasfrom boiler
Cold flue gasto stack Cold Air
Hot Air toBurners
Date of last change Reference/Name of Presentation/SN 81
Ljungstrom® RegenerativeAir Heater, Glossary
Source : Combustion, Fossil Power J.G. Singer 1991, ch 14 p 29 fig 27
Heat transferElements
Sootblowers
Hot End
Intermediate
Cold EndAxial seals
RotorRotor Housing
Pin rack
Radial sealsHot flue gasfrom boiler
Cold flue gasto chimney
Hot Airto burners
Cold air
Date of last change Reference/Name of Presentation/SN 82
Ljungstrom® RegenerativeAir Heater Issues
Leakages due to damaged axial orcircumferential sealsCold end baskets damaged by acid corrosion,Poor sootblowing, triggering firesStandby pneumatic or DC motor not working orabsentBroken / missing pins on the pin rack
- Heavy impact on boiler efficiency -- Heavy impact on boiler efficiency -
Date of last change Reference/Name of Presentation/SN 83
Boiler auxiliary : Sootblowers
Source : Combustion, Fossil Power J.G. Singer 1991, ch 14 p 39 fig 34
Date of last change Reference/Name of Presentation/SN 84
Sootblowers Issues
Locked, unable to travel in the furnaceAuxiliary steam not availableInsufficient number of sootblowersWear and tear of the steam nozzlesetc.
Date of last change Reference/Name of Presentation/SN 85
Boiler Auxiliary : fans
Inlet (Suction)
Inlet (Suction)
Discharge
Inletvanes
Source : Combustion, Fossil Power J.G. Singer 1991, ch 14 p 8 fig 5
Date of last change Reference/Name of Presentation/SN 86
Boiler Auxiliary : fans
Source : Combustion, Fossil Power J.G. Singer 1991, ch 14 p 8 fig 6
Date of last change Reference/Name of Presentation/SN 87
Boiler Auxiliary :Circulation Pump
Pump-EndBearing Housing
Stator WindingsStator laminations
Heat-ExchangerInlet Connection
Cover-EndJournal BearingThrust Disc andAuxiliary Impeller
Heat-ExchangerOutlet Connection
Impeller
Pump-EndJournal Bearing
Rotor
Motor Casing
Thrust Bearing
Terminal Gland
ElectricalTerminal Box
Filter
Inlet (Suction)
Reverse Thrust Bearing
DischargeDischarge
Source : Combustion, Fossil Power J.G. Singer 1991, ch 14 p 43 fig 37
Date of last change Reference/Name of Presentation/SN 88
Boiler Operation Improvement :Training
Source : Combustion, Fossil PowerJ.G. Singer 1991, ch 21 p 32
Date of last change Reference/Name of Presentation/SN 89
Safe Operation of Large Boilers
Protection against pressure surges– safety relief valves on drum, reheaters and
superheatersLack of water in the drum– automatic trip if level comes too low to avoid operation
of boiler without waterProtection against explosions in furnaces– boilers on-off safeties : burner management system– flame scanners
Environmental issues
Date of last change Reference/Name of Presentation/SN 90
Power Generation Glossary
Capacity Factor– energy generated by the unit during the reference period
divided by the energy that could have been generatedhad the unit run at its full rating over the entire period
Net Plant Heat Rate [ NPHR ]– the fuel-heat input required to generate one KWhr of
energy delivered to the grid
Auxiliary Power Charges– in-house power requirement of the installation (pumps,
fans, motors, etc.)
Date of last change Reference/Name of Presentation/SN 91
Power Generation Glossary (+)
Gross Plant Heat Rate– net plant heat rate plus the fuel-heat input needed to
cover the auxiliary power chargesReplacement Power Cost– the cost of purchasing the replacement energy if the
concerned installation is not operating, due to ascheduled or forced outage
Black Start Capability– in-house auxiliary generating station (diesel, generally)
to cover the auxiliary power charges necessary to startthe plant
Date of last change Reference/Name of Presentation/SN 92
A introduction to Boiler DesignBasics
Thank you for your attention
Boiler DesignBasics
Introduced !
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