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7/17/2019 Boiler Efficiency cal.pptx
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Energy Conservation and EnergyAuditing of Thermal Power Plant
In accordance with Energy Conservation Act, 2001,the Thermal Power Generating Stations have beennotied as the !esignated Cons"mers #!Cs$ by thegovernment and accordingly it has become
mandatory to carry o"t energy a"dit on a reg"larbasis and re%ort the energy conservation meas"resado%ted to &"rea" o' Energy E(ciency #&EE$) CEAin coo%eration with GT* "nder Indo+German Energy%rogram has %re%ared initial g"idelines 'or energya"diting o' Power Plants to %rovide common basis'or s"ch energy a"dits) These sho"ld be "sed 'orim%roving the energy e(ciency o' %ower %lants inthe co"ntry)
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The inistry o' Power, Government o' India and GT*
#!e"tsche Gesellscha't '-r Technische *"sammenarbeit#GT*$ Gmb.$ signed an /im%lementation agreement
with res%ect to the Indo+German Energy Programme in
200)
The Indo German Energy Programme #IGE$ is
%er'orming research wor3 and %er'ormance assessment in
s"%%ort o' the im%lementation o' the Energy
Conservation Act 2001 in coo%eration with the inistry o'
Power and its stat"tory bodies &"rea" o' Energy
E(ciency #&EE$, and Central Electricity A"thority #CEA$)
The Indo German EnergyProgramme (IGEN)
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The overall aim o' this meas"re "nder Indo Germany
Energy %rogramme is to s"%%ort and %re%are %"blic
and %rivate %ower %lant o%erators 'or %er'ormance
re%orting as well as im%lementation o' nancially
attractive and technically viable im%rovements o' %ower
%lant net heat rate "nder the %rovisions o' the
Energy Conservation Act)
The %ro5ect is being e6ec"ted "nder two main s"b+
com%onents7
1) a%%ing St"dies o' thermal %ower generating
The Indo German EnergyProgramme (IGEN)
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The 'ollowing o"tcomes are e6%ected o' the %rogramme7
a) Assistance in the im%roved e(ciency o' thermal
%ower %lants
b) Establishment o' ma%%ed %ower %lants data ban3
c) Establishment o' Energy E(ciency cell at Power
Plants
d) Ca%acity b"ilding o' the %ower %lant %ro'essional on
%ower
%lant o%timi9ation
Outcome E!ected from IGEN
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Economic growth in India, being de%endent on %owersector, has necessitated an enormo"s growth in electricity
demand over the last three decades) In 1;<=, the totalgeneration ca%acity was 1>0 ?, in 1;;1 it grew to@000 ? and as on date #CEA re%ort 10th A"g"st 2011$the installed ca%acity has grown to 1,1,@@ ? o' whichthermal ca%acity being 11<0; ?) any "ltra mega
%ro5ects "sing s"%ercritical boilers are in vario"s stages o'erectionBcommissioning)The 'ollowing is the brea3 "% o' installed ca%acity as on10BB2011)
Coal ;;@0> ?Gas 1==0 ?!iesel 1200 ?Thermal total 11<0; ? #@ D o' total installed
ca%acity$"clear <=0 ? , .ydro >20 ?
Power "cenario in India
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Energy Conservation and EnergyAuditing of Thermal Power Plant
Im%roving the energy e(ciency in %ower %lants can be
achieved by 71$ Im%roving energy e(ciency in e6isting %lants)
2$ .igher si9e "nits
>$ Technology ado%tion
Since the ma5or %ower generation contrib"tion is 'romthermal sector, an average increase o' 1D in the thermal%ower %lant e(ciency wo"ld res"lt in7
a) Coal savings o' a%%ro6) 11 million tons %er ann"m
b) >D C82 red"ction %er ann"m
c) .igher %rod"ctivity 'rom the same reso"rce is e"ivalent to
ca%acity addition)
d) Fower generation cost %er wh)
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Hollowing systems in Thermal Power Stations are
covered 'or energy a"diting)1) Coal handling %lant2) &oiler>) Thermal Ins"lation
<) Ash handling@) ?ater %"m%ing) Hans=) T"rbine) Condenser cooling;) Com%ressor air system10)otors11)Air Conditioning12)Fighting
Energy Conservation and EnergyAuditing of Thermal Power Plant
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Energy Performance Assessment of the #oiler
Per'ormance o' the boiler, li3e e(ciency and eva%orationrate red"ces with time, d"e to %oor comb"stion, heattrans'er 'o"ling and %oor o%eration and maintenance)!eterioration o' '"el "ality and water "ality also leads to%oor %er'ormance o' boiler) E(ciency testing hel%s "s to ndhow 'ar the e(ciency has dri'ted away 'rom the best
e(ciency) Any observed abnormal deviations co"ld there'orebe investigated to %in %oint the %roblem area 'or necessarycorrective action) .ence it is necessary to nd o"t thec"rrent level o' e(ciency 'or %er'ormance eval"ation, whichis %rere"isite 'or energy conservation action in %ower %lant)
$ocus should %e
• To concentrate on avoida%le losses
• &uantify the losses
• Identify ways and means for reduction
• Im!lementation
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#oiler
The boiler o' a thermal %ower %lant is "sed at high%ress"re and tem%erat"re re"ired 'or the steamt"rbine that drives the electrical generator) Theboiler has '"rnace, steam dr"m, s"%erheater coils,reheaters coils, economi9er and air heaters)
The air and "e gas %ath e"i%ment incl"de 'orceddra"ght 'ans #H!$) Ind"ced dra't 'ans #I!$,air%reheaters #AP.$, '"rnace, y ash collectors#electrostatic %reci%itators, bag lters$ and the "e
gas stac3) &rie' schematic diagram o' a ty%ical coalred s"b critical boiler is given in the 'ollowingg"re)
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"C'EATIC IAG*A O$ #OI+E*
Water cycle
Fuel cycle
Air & flue gas cycle
Steam cycle
Ash/ rejects cycle
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#OI+E* "PECI$ICATION $O* ,-. / 0/11NIT
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HACT8:S AHHECTIG PE:H8:ACE 8HC8&4STI8
SURFACE CONTACT AREA OF FUEL WT! AR
AR"FUEL RATO
RETENTON T#E
CO#$USTON C!A#$ER TE#%ERATURETUR$ULANCE N CO#$USTON C!A#$ER
RE#OAL OF %RO'UCTS OF CO#$USTON
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CO#1"TION
TIE"1$$ICIENT *ETENTION TIE 1"T #E A++O/E $O* T'E
$1E+ TO "TA2 IN"IE T'E $1*NACE TO COP+ETECO#1"TION3TIE *E&1I*E4A5AI+A#+E EPEN" $1E+T2PE6&1A+IT26"I7E$1*NACE "I7E6 5E+OCIT26 *A1G'T
TEPE*AT1*E
E$$ECT" T'E*A+ I$$1"ION O$ *EACTINGO+EC1+E" 1E TO INC*EA"E 5E+OCIT2 O$O+EC1+E" /IT' INC*EA"E IN TEPE*AT1*EIN$+1ENCE T'E *ATE O$ *EACTION
$ACTO*" A$$ECTING TEPE*AT1*E'EAT A#"O*#E #2 $1*NACE'EAT A#"O*#E #2 *EACTANT" TO #*ING T'E TOIGNITION TEPE*AT1*E'EAT A#"O*#E #2 NIT*OGEN IN AI*
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CO#1"TION
• T1*#1+ANCE ( #EC!ANCAL A)TATON OF REACTANTS TO $RN) T!E#
NTO %!*SCAL CONTACT
( RE+URE#ENT S #ORE AT FNAL STA)E OF CO#$USTON
( LESSER T!E TUR$ULANCE #ORE CAR$ON LOSS
( 'E%EN'S• WN' $O, TO FURNACE 'FF-%R-N CORNER FRE'
$OLERS
• TERTAR* AR N WALL FRE' $OLERS
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#oiler E8ciency Test
O!erational E8ciency of the #oiler9 The boiler e(ciency trial has to be cond"cted to
estimate o%erational e(ciency "nder as r"nconditions) The e(ciency eval"ation, by and large,'ollows the loss com%onents mentioned in there'erence standards 'or boiler testing at site "sing
indirect methods mentioned in &S <@7 1;= asamended on date and 4SA standard ASE #PTC+ <)1$Power Test Code 'or steam generators)
Indirect method is also called heat loss method) The
e(ciency can be arrived by s"btracting the heatloss 'ractions 'rom 100)
Pur!ose of Test 7 The !ur!ose of the test is
to calculate actual !erformance and e8ciency
of the %oiler and com!are it with design valuesor norms3 It is an indicator for trac:ing day to
il 8 i
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#oiler E8ciency#y ;boiler efciency ;is meant the meas"re o' ability o' a boiler or steamgenerator to trans'er the heat given , by the '"rnace to the water andsteam) It is dened as the heat added to the wor3ing "id e6%ressed as a
%ercentage o' heat in the '"el being b"rnt) &oiler loose heat beca"se it ise6tremely di(c"lt to recover all the heat)
&oiler e(ciency de%ends solely on the boilers ability to b"rn the '"el andtrans'er the res"lting heat to water and steam) The %ress"re andtem%erat"re o' steam %rod"ced does not have eJect on boiler e(ciency,tho"gh these %arameters have eJect on t"rbine cycle e(ciency) Generallys%ea3ing large boilers will have greater e(ciency d"e to im%roved designconstr"ction and better '"el b"rning arrangement)
A boiler, however, m"st be able to meet the 'ollowing design re"irements 7
1) &e able to %rod"ce steam at re"ired tem%erat"re and %ress"re over an arange o' load and ta3e in 'eed water at a tem%erat"re which varies with
t"rbine load)2) &e ca%able o' 'ollowing changes in demand 'or steam witho"t e6cessive
%ress"re swings which might li't the sa'ety valves or 'ail to meet the loadre"ired)
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There are two methods o' determining boiler e(ciency
1) !irect method2) Indirect or losses methodThe direct method 7 This method is straight 'orward
and consists o' meas"ring the heat s"%%lied to theboiler and heat added to the steam in the boiler in a
given time)E(ciency # 'or non reheat "nit$ #Enthal%y o' steam L Enthal%y o' 'eed water$M Steam
Hlow
#N"antity o' coal M CO$ ?S C%#T+To$ Q F Q #To L t$R 'M CO?S Steam ow rate C% S%ecic heat o'
steam T S) . Steam tem%erat"re To Sat"ration
#oiler E8ciency Calculationethods
il 8 i
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The tro"ble with this method is that several o' these"antities are di(c"lt to meas"re %artic"larly coal"antity, the steam "antity and CO o' coal) Theerror in meas"rement res"lts in an overalltolerance o' abo"t Q 1)@ D ) .owever this methodo' e(ciency determination is gaining %o%"larity o'
late and "sed more 're"ently beca"se o'sim%licity and advances being made inmeas"rement techni"es)
In indirect method, the e(ciency is calc"lated bydetermining the losses in the boiler)Hor this, chemical analysis o' the '"el and the "e gas
analysis are the basis o' calc"lation)
E(ciency 100 D + Fosses
#oiler E8ciencyethods
# il E8 i C l l i
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#oiler E8ciency Calculationethods Th"s i' losses are 3nown, the e(ciency can be
derived)
An im%ortant advantage o' this method is that theerrors in meas"rement do not ma3e signicantchanges in e(ciency)
Th"s i' boiler e(ciency is ;0 D an error o' 1D in directmethod will res"lt signicant changes in e(ciency)
;0Q 0); ;)1 to ;0);In indirect method, 1 D error in meas"rement o'losses will res"lt in
E(ciency 100 L #10Q0)1$ ;0 Q 0)1 ;); to ;0)1Clearly, the tolerance is narrow in losses method).owever beca"se o' advancement in instr"mentationand easiness the direct method is also becoming%o%"lar nowadays)
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+O""E" ENCO1NTE*E IN #OI+E*
• C8T:8FFA&FE
( C8&4STI&FE I AS. F8SS ( !: GAS F8SS
( C8 I HF4E GAS
( IFF :EECTS F8SS
( F8SSES !4E T8 P88: IS4FATI8• 4 C8T:8FFA&FE
( 8IST4:E I H4EF
( .!:8GE I H4EF
( AI: 8IST4:E ( SESI&FE .EAT I AS.
( :A!IATI8 A! 4ACC84TE!
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Controllable Variables Affecting Boiler
Performance
• S"%er heater Steam 8"tlet Tem%erat"re• :eheater Steam 8"tlet Tem%erat"re
• Air .eater Fea3age
• S"%er heater s%ray
• :eheater S%ray• .igh Primary airows
• Coal ill :e5ect
• .igh Carbon Content in Hly Ash
• .igh Carbon Content in &ottom Ash
• H"rnace E6it Gas Tem%erat"re
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Controlla%le 5aria%les A=ecting#oiler Performance
• Economi9er E6it Gas Tem%erat"re
• Air heater E6it gas Tem%erat"re
• &oiler air in lea3age
• A"6iliary Power Cons"m%tion o' Hans, ills andSoot &lowers
• E6cess 86ygen in Hl"e Gas
• Cycle Fosses d"e to Fea3ing Oent and !rainOalves
• Soot &lowing 8%timi9ation• ill Air In Fea3age on S"ction ills
• Steam P"rity Problems
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A*EA"4E&1IPENTCONT*I#1TING TO 5A*IO1"
+O""E" IN A #OI+E*
• CO#1"TION IN $1*NACE
• AI*'EATE* PE*$O*ANCE
• I++ PE*$O*ANCE• $AN" PE*$O*ANCE
• /ATE* +O""E"
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T2PICA+ #OI+E* +O""E"
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$ACTO*" /'IC' E$$ECT #OI+E*E$$ICIENC2 (#oiler +osses)
U Foss d"e to the heat carried away by hot "egases)
#a$ !ry "e gas loss, and #b$ ?et "e gas loss#lossd"e to moist"re in '"el and d"e to moist"re 'ormed bycomb"stion o' .2 in '"el$U oist"re in comb"stion air lossU 4nb"rnt carbon lossL Carbon in ash lossU 4nb"rnt gas loss L !"e to incom%lete comb"stion o'
carbonU E6cess air loss)U :adiation loss and "nacco"nted losses)U &low+ down and lea3ages)
!ry Hl"e gas Fosses 7 This is the heat loss in in the drycom onent o' the ases, as these are dischar ed 'rom
# il +
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#oiler +osses
/et $lue Gas +oss 9
!"e to moist"re in '"el 7 oist"re that enters the comb"stion
chamber as %art o' '"elBair ca"ses a heat loss beca"se itm"st be heated 'rom its initial tem%erat"re to boiling %oint,then eva%orated and nally s"%erheated to leave boiler atthe same tem%erat"re as "e gases) #ass"me latent heat o'eva%oration as 22@= B g at atmos%heric %ress"re$)
*adiation and 1naccounted +osses 7 It incl"des heatcarried away in ash, heat loss in bottom ho%%er and sealwater, loss 'rom boiler casing to s"rro"nding, losses d"e to"nb"rnt volatile matter etc) :adiation loss de%ends on theeJectiveness o' the boiler casing ins"lation)
#low down and ma:e u! 7 Ca"se two 'old losses L &y wayo' heat loss with blow down and s"bse"ent heating o' ma3e"% water)
#oiler E8ciency Ty!ical Eam!le
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#oiler E8ciency Ty!ical Eam!leaintaining e(ciency 7 The best way to analy9e the %roblemo' maintaining e(ciency is to e6amine the ma5or losses ine(ciency, what eJects them, and what can be done to
control them)
A ty%ical heat balance 'or a %"lveri9ed coal red "tility boilerwo"ld be 7
!ry gas loss
@)1 DFoss d"e to hydrogen and moist"re in the '"el <)> D
Foss d"e to "nb"rned comb"stible 0)@0 D
Foss d"e to radiation 0)>0
DFoss d"e to moist"re in air 0)1>D
an"'act"rers margin and "nacco"nted loss 1)@0 D
8verall e(ciency )0@
# il E8 i
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#oiler E8ciency
onitoring E8ciency 7 Contin"o"s monitoring o' "e
tem%erat"re and "e gas o6ygen content by reg"larly
calibrated recorder or indicator and by %eriodic chec3s oncomb"stibles in the re'"se will indicate i' original e(cienciesare being maintained) I' conditions vary 'rom the established%er'ormance base, corrective ad5"stments or maintenanceste%s sho"ld be ta3en)
.igh e6it+gas tem%erat"res and high dra't losses with normale6cess air indicates dirty heat absorbing s"r'aces and need'or soot blowing)
.igh e6cess air normally increases e6it gas tem%erat"res and
dra't losses and indicate the need 'or ad5"stment to the '"el+air ratio) The high e6cess air may, however, be ca"sed bye6cessive casing lea3s, cooling air, or air heater lea3s)
.igh comb"stible in the re'"se indicates a need 'orad5"stments or maintenance o' '"el %re%aration and b"rninge"i%ment)
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&oiler e(ciency varies with ty%e o' '"el)
8il B Coal being best and lowest with gas)
Coal %ro%erties directly aJect the e(ciency
o' the boiler oist"re in coal decreases boiler e(ciency)
E(ciency o' boiler will change i' the '"elred is not as %er the design #.igh HGET in
Tatas "nit @ boiler is d"e to high moist"reand high volatile matters in coal$)
#oilerE8ciency
#oiler +osses
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#oiler +osses
"TAC0 +O""
.eat carried away by "e gases or stac3 loss is the ma5or ca"se 'or the red"ction
o' boiler e(ciency)It is calc"lated as,
Stac3 Foss X Hl"e gas ow Y s%ecic heat o' "e gas 6 #"e gas e6it tem%erat"reL ambient tem%erat"re$
HACT8:S 8 ?.IC. STAC F8SS IS !EPE!ET
U S"l%her content o' '"el) #determines allowable "e gastem%erat"re at :AP. o"tlet$
U Ho"ling o' the '"rnace or air %re+ heater)
U E6cess air)
U Fea3ages into the '"rnace)
U .igh &"rner tilt)
U .igher level elevations in service)
U A"6iliary dam%er %ositions)
#oiler +osses
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'EAT CA**IE A/A2 #2 OI"T1*E
.eat absorbed by the moist"re in "e gases constit"tes a
loss beca"se, water va%o"r is not condensed in the boilerand th"s s"bstantial amo"nt o' latent heat #A%%ro6))@<0cal B 3g at atmos%heric %ress"re$ is lost)
There are two so"rces o' moist"re in "e gases vi9)
U oist"re in '"el)U Comb"stion %rod"ct o' hydrogen content in '"el)
S84:CE 8H 8IST4:E I HF4E GASES
U oist"re in '"els s"ch as coal and gas)
U H"els containing high hydrogen S"ch as nat"ral gasgenerate Farge amo"nt o' water va%o"r ?henb"rned) 2.2 Q 82 2.28
i)e ) 1 3g o' hydrogen, when b"rnt, %rod"ces ;3g o' water
va%o"r )
#oiler +osses
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INCOP+ETE CO#1"TION
Incom%lete comb"stion means %artial b"rning o' '"el)Part o' the '"el may remain "nb"rned or carbon in '"elmay b"rn %artially to 'orm carbon mono6ide)
Ca"ses o' incom%lete comb"stion are7U Inade"ate air)U Im%ro%er distrib"tion o' air)U H"el not %ro%erly %"lveri9ed or
atomi9ed)U Fow '"rnace tem%erat"res)U oist"re in '"el)U Fow secondary air tem%erat"res)
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/'2 INCOP+ETE CO#1"TION I" A +O""
U 4nb"rned '"el is obvio"sly a loss beca"se it releases noenergy, b"t is %aid 'or)U Partially b"rned carbon releases m"ch less energy thanwhen b"rnt '"lly)
2C Q 82 2C8 Q <,<00 &T4)C Q 82 C82 Q 1<,00 &T4)
As is evident %artial b"rning o' carbon generates carbon
mono6ide, a to6ic gas and releases m"ch less heat andth"s constit"tes a h" e loss)
# il +
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#oiler +osses
+oss due to ecess air 9
N"antity o' air s"%%lied over and above the minim"mre"ired amo"nt o' theoretically determined air#stoichometric$ is called e6cess air) Certain "antity o'e6cess air needs to be s"%%lied, beca"se it is%ractically not %ossible 'or every molec"le o' '"el tocome in contact with every molec"le o' o6ygens"%%lied in the limited time the mi6t"re remains inboiler with no e6cess air, res"lting in im%ro%ercomb"stion and conse"ent losses)
.owever, too m"ch e6cess air increases the amo"nt o'"e gases) Since, the tem%erat"re o' e6it gastem%erat"re is nearly constant , increase in "e gasow means increase in stac3 loss)
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+O"" 1E TO 'IG' E>CE"" O>2GEN
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INC*EA"E O$ E>CE"" O>2GEN ?. - , @ B
-.
,.
@.
.
B.
.
( O
N E
T O
* 2
+ O " " 4
) A 2
I N
* s 3
T '
O 1 "
A N )
"
+O"" 1E TO 'IG' E>CE"" O>2GEN
-? INC*EA"E IN E>CE"" O>2GEN /I++ +EA TO AN ANN1A++O"" O$
+O"" 1E TO 'IG' $3G3 TEP3AT A3'3
7/17/2019 Boiler Efficiency cal.pptx
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INC*EA"E IN A3'3 O1T+ET TEP .C
. B -. -B ,.
(
O N I T O
* 2
+
O " "
P E *
) A
2 I N
* s
3 T ' O 1 "
A N ) "
O1T+ET
INC*EA"E IN
$3G3TEP3 AT
A3'3 O1T+ET
#2 -..C
/I++ +EA TOAN ANN1A+
+O"" O$
*s3-C*O*E
$O* A ,-. /1NIT
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B
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-B
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7/17/2019 Boiler Efficiency cal.pptx
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#oiler Performance onitoring
Flue Gas Exit Temperature (FGET)
Reasons
?ater wall , s"%erheater Z :eheater s"r'aces
slagging Ho"ling in air %reheater Fow coal mill o"tlet tem%erat"re .igh moist"re and volatile matter in coal Fow Coal caloric val"e
Air lea3 in '"rnace .igh e6cess air
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7/17/2019 Boiler Efficiency cal.pptx
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#oiler Performance onitoring
Excess air & Air flo (Actionable)
E6cess air set %oint changed with load changes)
Carbon in ash monitored daily) Secondary air dam%ers, H"el air dam%ers Z a"6 air dam%ers are
chec3ed at reg"lar intervals) Act"al 82 in "e gas is com%ared with chemists readings) 82 %robes are calibrated at reg"lar intervals) !"ct lea3ages are identied and attended as soon as %ossible)
7/17/2019 Boiler Efficiency cal.pptx
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!R" F#$E GA% #%%
'EAT CA**IE A/A2#2 *2 $+1E GA" "' D /CP(TG F TA) 0cal4 0gf
/'E*E
/ /EIG'T O$ *2 $+1E GA" 0gm4 0gf
CP "PECI$IC 'EAT O$ *2 $+1E GA" 0cal4 0gm.
C TG GA" TEPE*AT1*E AT AI* 'EATE* O1T+ET .C TA A#IENT TEPE*AT1*E .C
COP1TATION O$ #OI+E* +O""E"
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COP1TATION O$ #OI+E* +O""E"
' !r flue gas loss*
+,ere C-BA . - of carbon in bottom as,
C-FA / - of carbon in fl as,
Bas, . Bottom as, 0unatiit in 1g
Fas, . Fl as, 0uantit in 1g
FGT . flue gas temperature at AP2 outlet in 3
C
ABT . Ambient temperature in C
Cp4 specific ,eat of fuel in 5cal61g C 4 378
COP1TATION O$ #OI+E* +O""E"
7/17/2019 Boiler Efficiency cal.pptx
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COP1TATION O$ #OI+E* +O""E"
7 #oss 9ue to unburnt carbon in as,*
[ ])%()%(,
/
,
BAsh BAC FAsh FAC GCV fuel of GCV
kg kcal incarbonof valueCalorific
Lashincarbonunburnt todue Loss uca
∗+∗∗
=
[ ]GCV
ABT FGT M
L fuel inmoisturetodue Loss mf
100584)(45.0(, ∗+−∗∗=
8 #oss 9ue to moisture in fuel*
: #oss 9ue to ,9rogen in fuel*
[ ]GCV
ABT FGT H
L fuel inhydrogentodue Loss hf
100584)(45.0(
9, 2
∗+−∗∗∗
=
Where !. ( g 0f !
. i1 2 g 0f fuel
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COP1TATION O$ #OI+E* +O""E"
; #oss 9ue to moisture in air*
GCV ABT FGT humidity AAS Lair inmoistureintodue Loss ma
100)(45.0, ∗−∗∗∗=
Where AAS3Actual mass 0f air su44lie5
!umi5ity 3 humi5ity 0f air i1 g/g 0f 5ry air
GCO
100@=<<
DC8DC8
CDC8F,6idecarbonmonotod"eFoss
2co
∗∗
+
∗=
GCO100@=<<2AhB3ginncons"m%tio'"el10%%minC8
F,mono6idecarbontod"eFoss
co
∗∗∗∗∗= −
< #oss 9ue to C in flue gas*
7/17/2019 Boiler Efficiency cal.pptx
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T2PICA+ #OI+E* 'EAT #A+ANCE
B=#ER
$0iler Efficie1cy 6!eat i1 Steam7
!eat l0ss 5ue t0 5ry flue gas
Dry Flue Gas Loss!eat l0ss 5ue t0 8et flue gas
!eat l0ss 5ue t0 m0isture i1 fuel
!eat l0ss 5ue t0 u19ur1ts i1 resi5ue
!eat l0ss 5ue t0 m0isture i1 air
!eat l0ss 5ue t0 ra5iati01 & 0ther
u1acc0u1te5 l0ss
;;-
:7-
'-
38-
'-
'-
>?-
'33-!eatfr0m
Fuel
E>P+O*ATION O$ E$$ICIENC2 IP*O5EENT
7/17/2019 Boiler Efficiency cal.pptx
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OPPO*T1NITIE"
$0ilers:Steam and water %arameters # ow, %ress"re and
tem%erat"re $
Air and gas %arameters # ow, %ress"re andtem%erat"re $
&"rners o%eration Primary and secondary air ratios and tem%erat"res Air inltration in to boilersAir inltration to "e gases 4nb"rnt loss red"ction
Comb"stion control L boiler e6cess air, 82eas"rement
inacc"racy !ry "e gas loss
Ins"lation
E>P+O*ATION O$ E$$ICIENC2
7/17/2019 Boiler Efficiency cal.pptx
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IP*O5EENT OPPO*T1NITIE"Coal "ality and %er'ormance o' coal mills S"%er heater and reheater %er'ormance S"%er heater tem%erat"re, slagging o' '"rnace waterwalls and t"bes Ho"ling on the %endant and hori9ontal convectiont"bes, soot blowers %er'ormance
&oiler control systems Fimitation on Per'ormance o' associated e"i%ments#%"m%s, 'ans, heaters, soot blowers, mills, etc$ aJectingboiler loading and e(ciency Foading on I!, H! and PA 'ans 8%eration o' dam%ers Binlet g"ide vanes B s%eedcontrollers o' 'ans Ho"ling o' boiler heating s"r'aces Installation o' energy saving retrots