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Welcome to A presentation on

RAMAGUNDAM

A presentation on

A DMAIC Project on'Optimisation of Boiler Exit Flue

Gas Temperatures at Unit 7'Gas Temperatures at Unit-7

Venue: 7th National Quality Conclave

RAMAGUNDAM

Lostt

Singareni, WCL, Sriramsagar

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TYPICAL VALUES

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WINDBOX/SADC WINDBOX/SADC

COALfurnace

MILLS A,B,C,DE,

MILLS F,G,H,J,K

Sec. AirDivisional Panel Super

Heater

Platen Super Heater

Reheater

FW FW

PAH-A SAH-A SAH-B PAH-B

PA to MillsPA to Mills

Drum

LTSH

Economiser

Secondary AirP i i

ESP C ESP C ESP B ESP AESP Inlet Header

ESP Inlet Header

Primary air

Chimney

ID Fan B ID Fan A

Reduce the Reduce the

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OBJECTIVE OF THE PROJECT

average flue gas average flue gas

temperature at temperature at

Air Preheater Air Preheater

outlet in unitoutlet in unit--77

CONTROLCONTROLSTANDING INSTRUCTIONS

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ANALYSISANALYSIS

IMPROVEIMPROVE

ANALYSIS OF PAST/DOE DATA

RECOMMENDED SETTINGS

DEFINEDEFINE

MEASUREMEASURE

DEVELOPING BUSINESS CASEWITH POTENTIAL BENEFITS

HISTORICAL/LIVE DATA COLLECTION

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AVERAGE FGT IN JANAVERAGE FGT IN JAN 20112011 147 8147 8 OO CC

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AVERAGE FGT IN JANAVERAGE FGT IN JAN--20112011-- 147.8 147.8 OO CC(Unit Overhaul was done in August 2010 )(Unit Overhaul was done in August 2010 )

Design VALUES Design VALUES ((AT RATED CONDITIONSAT RATED CONDITIONS ))

125125 OO C ( at NCR) /128 C ( at NCR) /128 OO C ( at BMCR)C ( at BMCR)

Note : 21 Note : 21 OO C Reduction of FGT results in 1% improvement in C Reduction of FGT results in 1% improvement in Boiler EfficiencyBoiler Efficiency

LB USL

LB 120Target *

Process Data WithinOverall

Unit-7 Capability Analysis-Jan-11

RAMAGUNDAM

TargetUSL 135Sample Mean 147.759Sample N 2761StDev (Within) 0.631459StDev (O v erall) 9.69413

C p *C PL *C PU -6.74C pk -6.74

Pp *PPL *PPU -0.44Ppk -0.44C pm *

O v erall C apability

Potential (Within) C apability

172.5165.0157.5150.0142.5135.0127.5120.0

PPM < LB 0.00PPM > USL 886997.46PPM Total 886997.46

O bserv ed PerformancePPM < LB *PPM > USL 1000000.00PPM Total 1000000.00

Exp. Within PerformancePPM < LB *PPM > USL 905944.62PPM Total 905944.62

Exp. O v erall Performance

RAMAGUNDAM RAMAGUNDAM

Through Brainstorming the following were Through Brainstorming the following were identifiedidentified

Key performance input variables Key performance input variables –– 18 no.18 no.

Key performance output variables Key performance output variables --4 no4 no

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1.1. Coal FlowCoal Flow2.2. Primary Air FlowPrimary Air Flow3.3. Secondary Air FlowSecondary Air Flow4.4. Burner Tilt Position Cornerwise (Give Corner numbers)Burner Tilt Position Cornerwise (Give Corner numbers)

NTPC,RAMAGUNDAMRAMAGUNDAM

( )( )5.5. Each Mill Outlet temp ( which are in service)Each Mill Outlet temp ( which are in service)6.6. Wind Box DPWind Box DP7.7. APH soot blowing timingsAPH soot blowing timings8.8. Air pre Heater air inlet temp (APHAir pre Heater air inlet temp (APH--Wise)Wise)9.9. Air Pre Heater outlet Damper Position (APHAir Pre Heater outlet Damper Position (APH--wise)wise)10.10. Super Heater Spray (tph)Super Heater Spray (tph)11.11. Steam FlowSteam Flow

( h)( h)12.12. ReRe--Heater Spray (tph)Heater Spray (tph)13.13. FAD PositionFAD Position14.14. OFD positionOFD position15.15. Wall blowing Status (timings and no of blowers Operated)Wall blowing Status (timings and no of blowers Operated)16.16. LRSB Operation details (timings, date, number of blowers(groupLRSB Operation details (timings, date, number of blowers(group--wise wise

))))17.17. Mill Combination details (which mill, feeding rate each mill(tph))Mill Combination details (which mill, feeding rate each mill(tph))18.18. Load in MWLoad in MW

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FGT AT PAPHFGT AT PAPH--A OUTLETA OUTLET

FGT AT PAPHFGT AT PAPH--B OUTLETB OUTLET

FGT AT SAPHFGT AT SAPH--A OUTLETA OUTLET

FGT AT SAPHFGT AT SAPH--B OUTLETB OUTLET

Note: All the above four variables are combined to form a single output variable as Average Flue Gas Temperature at Air Pre-heater Outlet

RAMAGUNDAM

Mill CombinationMill Combination Average Mill Height ( Fire Ball Height)Average Mill Height ( Fire Ball Height) Wear Out of Combustion ComponentsWear Out of Combustion Components Performance of Feed Water HeatersPerformance of Feed Water Heaters

APH I t l C ditiAPH I t l C diti APH Internal ConditionAPH Internal Condition

f Sf S

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Process Information ServerProcess Information ServerControl Room DASControl Room DASPADOPADO

Note: No MSA was done as the source of data is most Note: No MSA was done as the source of data is most reliable.reliable.

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RAMAGUNDAM

ANALYZEANALYZE

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TOOLS USEDTOOLS USED

Normality TestMultiple Regression Analysis, Capability Analysis

Partial Least Square Regression AnalysisDESIGN OF EXPERIMENTS

99.99Mean 147 8

Unit-7 APHs Outlet FGTNormal

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Normality test

99

95

80

50

20Perc

ent

Mean 147.8StDev 9.693N 2761AD 24.097P-Value <0.005

190180170160150140130120110

20

5

1

0.01

AVE.FG TEMP AFTER APHs (DEG C)

Average data was retrieved every 15 minutes block wise during the month of january-2011, from PI Server.

MULTIPLE REGRESSION

RAMAGUNDAM

Results of Regression Analysis (Jan-2011): S = 2.18163 R-Sq = 93.5% R-Sq(adj) = 93.2%

Analysis of Variance

Source DF SS MS F PRegression 48 79204.2 1650.1 346.69 0.000Regression 48 79204.2 1650.1 346.69 0.000Residual Error 1159 5516.3 4.8Total 1207 84720.5

This means 93.2 % of the variation is explainedby the Predictors.

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Analysis : Result of MLRAnalysis : Result of MLR

Predictor Coef SE Coef T P VIFC 188 203 1 0 93 0 3 4

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Constant -188.5 203.1 -0.93 0.354FW TEMP AT ECO INLET -0.02803 0.01308 -2.14 0.032 9.913FW TEMP AT ECO OL LHS 1.28405 0.08315 15.44 0.000 23.671FW TEMP AT ECO OL RHS 0.32995 0.08727 3.78 0.000 32.563MS TEMP LHS -0.00972 0.01823 -0.53 0.594 1.427MS TEMP RHS -0.08661 0.01433 -6.05 0.000 3.258PAH-A FG OL DMAPER -0.28817 0.09190 -3.14 0.002 40.607SAH-A FG OL DAMPER -1.3339 0.9318 -1.43 0.153 19.199SAH-A OL DAMPER2 0.5145 0.2261 2.28 0.023 39.740PAH-B FG OL DAMPER 0.05151 0.08334 0.62 0.537 38.787SAH-B FG OL DAMPER 1.540 2.610 0.59 0.555 23.743

NTPC, RamgundamNTPC, Ramgundam

SAH B FG OL DAMPER 1.540 2.610 0.59 0.555 23.743BLI 0.033857 0.003968 8.53 0.000 70.241FW FLOW -0.003565 0.002560 -1.39 0.164 36.367TOTAL AIR -0.033538 0.003330 -10.07 0.000 34.286TOTAL FUEL -0.04104 0.01088 -3.77 0.000 26.289BT CORNER-1 FDBK 0.04183 0.01610 2.60 0.009 2.135BT CORNER-2 FDBK 0.23895 0.02453 9.74 0.000 13.552BT CORNER-3 FDBK -0.23302 0.04414 -5.28 0.000 31.201

Analysis : Result of MLRAnalysis : Result of MLR

Predictor Coef SE Coef T P VIFBT CORNER 4 FDBK 0 08246 0 05716 1 44 0 149 31 829

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BT CORNER-4 FDBK 0.08246 0.05716 1.44 0.149 31.829FURN WB DP-1 -0.04787 0.06216 -0.77 0.441 18.490FURN WB DP LHS 0.21911 0.06130 3.57 0.000 19.710AUX AIR DAMPER CONTROL 0.06351 0.02296 2.77 0.006 7.403U OFA POSITION 0.0733 0.1084 0.68 0.499 276.472LOWER OFA POSITION 0.0020 0.1090 0.02 0.986 276.872FAD -A 0.13286 0.02731 4.87 0.000 4.784FAD -B -0.05300 0.01928 -2.75 0.006 5.356FAD -C 0.1934 0.1110 1.74 0.082 2.583FAD -D 0.07092 0.02895 2.45 0.014 4.707FAD -E 0.07978 0.02862 2.79 0.005 3.544

NTPC, RamgundamNTPC, Ramgundam

FAD -F -0.03438 0.01569 -2.19 0.029 3.773FAD -G 0.00635 0.04108 0.15 0.877 9.274FAD H -0.020400 0.009823 -2.08 0.038 2.924FAD -J 0.00542 0.01177 0.46 0.645 5.914FAD -K 0.014036 0.009818 1.43 0.153 5.378MILL A (TPH) 0.02146 0.02064 1.04 0.299 6.946MILL B(TPH) 0.04156 0.01401 2.97 0.003 9.494

Analysis : Result of MLRAnalysis : Result of MLR

Predictor Coef SE Coef T P VIFMILL C (TPH) 0 04593 0 02313 1 99 0 047 1 816

RAMAGUNDAM

MILL C (TPH) -0.04593 0.02313 -1.99 0.047 1.816MILL D (TPH) -0.03589 0.01568 -2.29 0.022 10.143MILL E (TPH) 0.06877 0.02553 2.69 0.007 1.832MILL F (TPH) -0.03352 0.01438 -2.33 0.020 9.412MILL G (TPH) 0.04066 0.03197 1.27 0.204 10.529MILL H (TPH) 0.01426 0.01179 1.21 0.227 9.675MILL J (TPH) 0.02730 0.01337 2.04 0.041 18.297MILL K (TPH) 0.00993 0.01341 0.74 0.459 24.144SEC AIR FLOW (TPH) 0.012923 0.003175 4.07 0.000 11.781SH SPRAY L(TPH) -0.04677 0.01461 -3.20 0.001 7.407SH SPRAY R(TPH) -0.19350 0.01907 -10.15 0.000 4.608

NTPC, RamgundamNTPC, Ramgundam

RH SPRAY L(TPH) 0.06820 0.02577 2.65 0.008 2.923RH SPRAY R(TPH) -0.02590 0.01838 -1.41 0.159 4.001

VIF value more than 5 indicates multi-collinearity. This limits the application of Multiple Linear regression for our purpose.

The objective was to identify the The objective was to identify the ‘i d d t F t ’ hi h l i th‘i d d t F t ’ hi h l i th

DATA ANALYSIS

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‘independent Factors’ which explain the ‘independent Factors’ which explain the variation in the ‘dependent’ variable.variation in the ‘dependent’ variable.

Partial Least Square Regression (PLSR) was Partial Least Square Regression (PLSR) was used to identify those factors whichused to identify those factors whichused to identify those factors which used to identify those factors which explain the variation in FG Exit Tempexplain the variation in FG Exit Temp..

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Analysis of Variance for AV. FG TEMP BEF PAH-A(DEG C)

Source DF SS MS F P

RAMAGUNDAM

Source DF SS MS F PRegression 10 72934.4 7293.44 740.73 0.000Residual Error 1197 11786.1 9.85Total 1207 84720.5

Model Selection and Validation for AV. FG TEMP BEF PAH-A(DEG C)

Components X Variance Error R-Sq1 0.216269 21298.9 0.7485982 0.408405 15492.3 0.8171363 0.503300 13118.0 0.8451614 0.602220 12501.2 0.8524425 0.664218 12207.0 0.8559156 0.722221 12047.0 0.8578037 0.761089 11881.8 0.8597538 0.808531 11799.4 0.8607269 0.883109 11791.0 0.86082510 0.944084 11786.1 0.860883

PLS Coefficient Plot(response is AV. FG TEMP BEF PAH-A(DEG C))

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94.4 % of theVarianceExplained by the model

1.5

1.0

0.5

0 0effic

ient

s

10 components

454035302520151051

0.0

-0.5

-1.0

Predictors

Coe

RAMAGUNDAM

1. Average Mill Outlet Temperature2. Total Primary Air3. Total Secondary air4. Burner Tilt5. Wind Box DP6 SAPH A d P

These Nine

variables are

found to be6. SAPH-A gas damper Position7. SAPH-B gas damper Position8. FAD-D,E,F Position9. Coal Flow

found to be

explaining

the variation

in APHs FGT

A Statistical method was used to find out the A Statistical method was used to find out the

RAMAGUNDAM

Variables affecting the mostVariables affecting the most

Relative effect of each variableRelative effect of each variable

Interaction effect of certain variablesInteraction effect of certain variables

Optimum settings of the variablesOptimum settings of the variables

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DOEDOE--Randomized two level Plan for UnitRandomized two level Plan for Unit--77--Rdm (ResolutionRdm (Resolution--IV)IV)

RunOrderRunOrder

Total Total Primary Primary

AirAir

Total Total Secondary Secondary

AirAir

Mills Mills Outlet Outlet

TempTemp--AvAv

Burner Burner Tilt Tilt

PositionPosition

Wind Wind Box DP Box DP

L&RL&R

APHAPH--SecSec--AA--GDGD--

PositionPosition

APHAPH--SecSec--BB--GDGD--

PositionPosition

FADFAD--D,E D,E &F &F

PositionPosition11 700700 12251225 9090 2020 7070 6565 9090 1515

RAMAGUNDAM

22 700700 11501150 9090 4040 7070 9090 6565 151533 610610 11501150 9090 2020 100100 9090 9090 151544 610610 12251225 7575 4040 7070 9090 9090 151555 610610 12251225 9090 4040 100100 6565 6565 151566 610610 11501150 7575 2020 7070 6565 6565 151577 700700 11501150 7575 4040 100100 6565 9090 151588 610610 12251225 9090 2020 7070 9090 6565 303099 700700 12251225 7575 4040 7070 6565 6565 3030

1010 700700 12251225 9090 4040 100100 9090 9090 30301111 610610 11501150 7575 4040 100100 9090 6565 30301212 700700 11501150 7575 2020 7070 9090 9090 30301313 610610 12251225 7575 2020 100100 6565 9090 30301414 610610 11501150 9090 4040 7070 6565 9090 30301515 700700 12251225 7575 2020 100100 9090 6565 15151616 700700 11501150 9090 2020 100100 6565 6565 3030

General Regression Equation (With Coal Flow included)General Regression Equation (With Coal Flow included)

RAMAGUNDAM

g q ( )g q ( )

Av. FG Temp Aft APHs Av. FG Temp Aft APHs = 367.991 = 367.991 -- 0.646082 Coal Flow 0.646082 Coal Flow --1.30724 Av. Mill O/L temp + 0.101233 P. Air Flow + 1.30724 Av. Mill O/L temp + 0.101233 P. Air Flow + 0.0579856 S. Air Flow +0.0579856 S. Air Flow + 0.00286993 F. WB DP 0.00286993 F. WB DP -- 0.378581 0.378581 Burner Tilt % (calculated) + 0.000431769 SAPH_A GD POS + Burner Tilt % (calculated) + 0.000431769 SAPH_A GD POS + 0 0196207 SAPH B GD POS + 0 0162723 FAD0 0196207 SAPH B GD POS + 0 0162723 FAD--DD0.0196207 SAPH_B GD POS + 0.0162723 FAD0.0196207 SAPH_B GD POS + 0.0162723 FAD--DD

Coefficients

Term Coef SE Coef T P VIF

RAMAGUNDAM

Constant 367.991 33.1322 11.1068 0.000Coal Flow -0.646 0.1002 -6.4480 0.000 2.83463P. Air Flow 0.101 0.0145 6.9696 0.000 2.88370S. Air Flow 0.058 0.0072 8.0254 0.000 1.42337F. WB DP 0.003 0.0293 0.0981 0.922 1.09665Burner Tilt % (calculated) -0.379 0.0690 -5.4849 0.000 1.18030Av. Mill O/L temp -1.307 0.0557 -23.4625 0.000 1.07640SAPH_A GD POS 0.000 0.0240 0.0180 0.986 1.05573SAPH_B GD POS 0.020 0.0235 0.8333 0.410 1.01454FAD-D 0.016 0.0283 0.5749 0.569 1.07696

Summary of Model

S = 2.83424 R-Sq = 95.54% R-Sq(adj) = 94.49%PRESS = 476.167 R-Sq(pred) = 93.05%

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Analysis of Variance

Source DF Seq SS Adj SS Adj MS F PRegression 9 6541.71 6541.71 726.86 90.485 0.000000Coal Flow 1 1122.04 333.98 333.98 41.576 0.000000P. Air Flow 1 252.10 390.20 390.20 48.575 0.000000S. Air Flow 1 486.29 517.37 517.37 64.406 0.000000F. WB DP 1 57.78 0.08 0.08 0.010 0.922363Burner Tilt % (calculated) 1 190.28 241.66 241.66 30.084 0.000003Av. Mill O/L temp 1 4425.11 4422.03 4422.03 550.489 0.000000pSAPH_A GD POS 1 0.02 0.00 0.00 0.000 0.985752SAPH_B GD POS 1 5.43 5.58 5.58 0.694 0.409883FAD-D 1 2.66 2.66 2.66 0.331 0.568719

Error 38 305.25 305.25 8.03Total 47 6846.96

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PLS Regression: Av. FG Temp versus Coal Flow, P. Air Flow, S. Air Flow, ...

RAMAGUNDAM

Analysis of Variance for Av. FG Temp Aft APHs

Source DF SS MS F PRegression 8 6300.05 787.506 56.16 0.000Residual Error 39 546.91 14.023Total 47 6846.96

Model Selection and Validation for Av. FG Temp Aft APHs

C t X V i E R SComponents X Variance Error R-Sq1 0.22263 1730.98 0.7471902 0.40773 728.77 0.8935623 0.50477 587.60 0.9141804 0.59605 557.10 0.9186365 0.64461 547.11 0.9200956 0.76266 546.92 0.9201237 0.87466 546.91 0.9201238 1.00000 546.91 0.920123

PLS Coefficient Plot(response is Av. FG Temp Aft APHs)

8 components

RAMAGUNDAM

0.0

-0.2

-0.4

-0.6

-0.8Coef

ficie

nts

87654321

-1.0

-1.2

-1.4

Predictors

C

Analysis: Result of DOEAnalysis: Result of DOE

Model term Sum of squares

% contri-bution

Sl no

RAMAGUNDAM

1 PA Flow 66.898 2.942 SA flow 105.164 4.623 WB_DP 0.07123 0.014 Burner tilt 34.0668 1.55 Mill outlet temp 1844.91 80.956 SAPH_A 12.9722 0.577 SAPH_B 1.32397 0.06

squares bution

Since Contribution to sum of squares is negligible, factors

3, 6,7,8 are removed from the

ANOVA table.

NTPC, RamgundamNTPC, Ramgundam

8 FAD-D 0.42901 0.021 x 5 52.6667 2.321 x 8 89.1388 3.92Error 71.67929 3.15SStotal 2279.32 100.06

Analysis: ANOVA TableAnalysis: ANOVA Table

RAMAGUNDAM

ANOVA table

PA Flow 66.898 1 66.898 6.96244 5.11736 0.026973679 Significant Low

SA flow 105.164 1 105.164 10.945 5.11736 0.009108243 Significant Low

Burner tilt 34.0668 1 34.0668 3.54552 5.11736 0.092369638 NOT SIGNIFICANT

Mill outlet temp 1844.91 1 1844.91 192.01 5.11736 0.000000224 Significant High

1X5 / 2X7 52 6667 1 52 6667 5 48131 5 11736 0 043932387 Significant

Source of variation

SS

Interaction

Preferred settings

df MS Fcalc Ftab p-Value

Main Effects

1X5 / 2X7 52.6667 1 52.6667 5.48131 5.11736 0.043932387 Significant

1X8 / 2X4 / 3X5 89.1388 1 89.1388 9.27716 5.11736 0.013885968 SignificantError 86.4757 9 9.60841Total 2279.32 15

Interaction effects

02/05/2012

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RAMAGUNDAM

Variables influencing mostVariables influencing most

Average Mill Outlet TemperatureAverage Mill Outlet TemperatureTotal Secondary Air FlowTotal Secondary Air FlowTotal Primary Air FlowTotal Primary Air FlowCoal FlowCoal Flow

Variables showing interaction effectsVariables showing interaction effects

RAMAGUNDAM

Variables showing interaction effectsVariables showing interaction effects

Wind box DPWind box DPSAPHSAPH--A gas damper positionA gas damper positionSAPHSAPH B gas damper positionB gas damper positionSAPHSAPH--B gas damper positionB gas damper positionFADFAD--D,E,F positionD,E,F positionBurner tiltBurner tilt

Final recommended settings after DOEFinal recommended settings after DOE

Average Mill Outlet Temperature At Around 90 DegAverage Mill Outlet Temperature At Around 90 Deg

RAMAGUNDAM

Total Secondary Air At Around 1100 TPH Total Secondary Air At Around 1100 TPH

Primary Air At Around 660 TPH (Min)Primary Air At Around 660 TPH (Min)

Burner Tilt At 45 % (Slightly Above Horizontal)Burner Tilt At 45 % (Slightly Above Horizontal)

Wind Box DP At Practical Minimum Between 70 And 100 MMWCWind Box DP At Practical Minimum Between 70 And 100 MMWC

SAPH A& B Gas Dampers At Practical Maximum Between 65% To SAPH A& B Gas Dampers At Practical Maximum Between 65% To 100%100%100%100%

Keep FADKeep FAD--D At Practical Maximum Position Between 15 And 40 D At Practical Maximum Position Between 15 And 40 %.%.

15 Minute Average Values during Implementation of recommendation 15 Minute Average Values during Implementation of recommendation MinimumMinimum MaximumMaximum AverageAverage

Coal FlowCoal Flow 329.33329.33 400.08400.08 358.70358.70

Implementation of Recommendations ( 382 Hrs from 02-11-2011 to 25-11-2011)

RAMAGUNDAM

P Air FlowP Air Flow 645.90645.90 744.44744.44 671.48671.48S Air FlowS Air Flow 1070.051070.05 1129.981129.98 1106.081106.08Av. Mill O/L TempAv. Mill O/L Temp 86.0086.00 91.7291.72 88.6888.68Actual AV FGT APH O/LActual AV FGT APH O/L 116.34116.34 143.97143.97 129.29129.29

Av. FGT at APH O/LAv. FGT at APH O/L (When Coal Flow is Maximum)(When Coal Flow is Maximum) 124.95124.95Av FGT at APH O/LAv FGT at APH O/L (When Coal Flow is Minimum)(When Coal Flow is Minimum) 139 38139 38Av. FGT at APH O/LAv. FGT at APH O/L (When Coal Flow is Minimum)(When Coal Flow is Minimum) 139.38139.38Av. FGT at APH O/LAv. FGT at APH O/L (When Av Mill O/l Temp is Maximum)(When Av Mill O/l Temp is Maximum) 120.5120.5Av. FGT at APH O/LAv. FGT at APH O/L (When Av Mill O/l Temp is Minimum)(When Av Mill O/l Temp is Minimum) 123.5123.5Decrease in FGT in Deg C at APH O/L per every Ton increase in coal Decrease in FGT in Deg C at APH O/L per every Ton increase in coal FlowFlow 0.2040.204Decrease in FGT at APH O/L per every Degree increase in Av Mill O/L Decrease in FGT at APH O/L per every Degree increase in Av Mill O/L Temp Temp 0.5300.530

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LSL Target USLProcess Data Within

Unit-7 APHs FGT Capability after Implementation-Nov-11(using 95.0% confidence)

RAMAGUNDAM

LSL 120Target 130USL 135Sample Mean 128.742Sample N 1529StDev (Within) 0.466578StDev (O v erall) 6.53012

Process Data

Z.Bench *Z.LSL 18.74Z.USL 13.41C pk 4.47Upper C L 4.60

Z.Bench 0.65Z.LSL 1.34Z USL 0 96

O v erall C apability

Potential (Within) C apability

WithinOverall

145140135130125120115

Upper C L 0.34C pm 0.25

Z.USL 0.96Ppk 0.32

PPM < LSL 102681.49PPM > USL 162851.54PPM Total 265533.03

O bserv ed PerformancePPM < LSL 0.00PPM > USL 0.00PPM Total 0.00

Exp. Within PerformancePPM < LSL 90336.40PPM > USL 168939.85PPM Total 259276.26

Exp. O v erall Performance

BeforeBeforeAfter

RAMAGUNDAM

BeforeBefore

Limitations For Continuous OperationLimitations For Continuous Operation

RAMAGUNDAM

Fire in Mill rejects at 90Deg C Fire in Mill rejects at 90Deg C ––for certain types for certain types of Coals of Coals (Coal with high Sulfur/Iron content)(Coal with high Sulfur/Iron content)

Maintaining Recommended air flow becomes Maintaining Recommended air flow becomes difficult because of Clinkering problems difficult because of Clinkering problems

Burner Tilt is essentially required to Maintain Burner Tilt is essentially required to Maintain rated steam parametersrated steam parameters

RAMAGUNDAM

Trial run carried out with recommended settings and with Trial run carried out with recommended settings and with settings settings awayaway from recommended values for a short duration from recommended values for a short duration of 6 Hours for reconfirming the results of 6 Hours for reconfirming the results

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Absolute reduction in Av FGT after APHs= 18 deg CAbsolute reduction in Av FGT after APHs= 18 deg C

Tangible Gains achievedRAMAGUNDAM

Reduction due to Coal Quality variation = 9.5 Deg C Reduction due to Coal Quality variation = 9.5 Deg C

Net FGT reduction achieved = 8.5 Deg C Net FGT reduction achieved = 8.5 Deg C

Computed gain in Heat Rate: 9.7 K.Cal / KWHComputed gain in Heat Rate: 9.7 K.Cal / KWH

RAMAGUNDAM

Sustenance PlansSustenance Plans

11 Standing Instructions to theStanding Instructions to the1.1. Standing Instructions to the Standing Instructions to the operator to maintain the operator to maintain the recommended settings recommended settings

2.2. Sharing of the knowledge with all Sharing of the knowledge with all concernedconcerned

3.3. Monitoring through ORT meetingsMonitoring through ORT meetings

Intangible GainsIntangible Gains

d l S l ld l S l l

RAMAGUNDAM

Learned a Versatile Statistical tool Learned a Versatile Statistical tool which will be very useful in a Power which will be very useful in a Power Plant operationsPlant operations

02/05/2012

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RAMAGUNDAM

Just by changing operating practices, it is Just by changing operating practices, it is

possible to achieve a substantial possible to achieve a substantial

reduction of 8.5 reduction of 8.5 00 c in FGT at APHS c in FGT at APHS

outlet in unitoutlet in unit 77outlet, in unitoutlet, in unit--77..

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