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BTL

NoUnit Trip date

Synchro

Date

BTL

AreaOutage hrs MU Lost

SD Oil

(kL)

Start Up

Oil (kL)

Outage

Cost

(crores)

1 226-04-2010

11:53

01-05-2010

05:15Mid RH 113.37 34.01 6.65 130 6.36

2 105-05-2010

03:01

06-05-2010

17:58

Bottom

ring header38.95 11.69 5 90 2.42

3 116-06-2010

02:42

22-06-2010

12:48LTSH 154.10 46.23 54.45 165 8.82

4 203-07-2010

07:13

06-07-2010

01:33

Econo -

miser66.33 19.9 11.5 149 4.12

5 1 16-07-201018:10 21-07-201004:23 LTSH 106.22 31.87 10 118.8 5.976 2

20-01-2011

22:48

23-01-2011

08:12LTSH 57.40 17.22 4 110.5 3.45

FIN YR TOTAL 536.37 160.91 91.60 763.30 31.14

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BTL

No

UnitTrip

date

Synchro

Date

BTL

Area

Outage

hrs

MU

Lost

SD

Oil

(kL)

Start

Up Oil

(kL)

Outage

Cost

(crores)

1 208-05-2011

23:26

13-05-2011

05:25LTSH 101.98 30.595 1.65 122 5.73

21

13-06-2011

13:17

16-06-2011

01:09

Water

Wall59.87 17.96 3.3 54.45 3.29

3 226-06-2011

20:41

01-07-2011

08:14

Water

Wall107.55 32.265 1.65 117.15 5.98

41

01-08-2011

17:09

05-08-2011

05:41 LTSH84.53 25.36 1.65 99

4.74

5 221-11-2011

23:19

25-11-2011

14:21LTSH 87.03 26.11 16.5 126 5.07

FIN YR TOTAL 440.97 132.2924.75 518.60 24.82

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BTL

NoUnit

Trip

date

Synchro

Date

BTL

Area

Outage

hrs

MU

Lost

SD Oil

(kL)

Start Up

Oil (kL)

OutageCost

(crores)

1 218-04-2012

23:51

22-04-2012

13:30Near IK 36 85.65 25.695 37.95 110.55 5.10

2 125-04-2012

10:29

27-04-2012

16:06 Water Wall 53.62 16.085 6.6 97 3.25

3 228-04-2012

21:30

03-05-2012

02:44LTSH 101.23 30.37 6.6 112.6 5.72

4 103-05-2012

12:43

06-05-2012

13:52LTSH 73.15 21.945 6.6 80.85 4.14

FIN YR TOTAL 313.65 94.09 57.75 401.00 18.21

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FIN YR NO OF BTL

TOTAL

OUTAGE

HRS

TOTAL OUTAGE

COST

2010 11 6 536.3731.14

CRORES

2011 12 5 440.97 24.82CRORES

2012 13

(Till Date) 4 313.65

18.21

CRORES

TOTAL 15 1290.9974.17

CRORES

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BTL

No

Unit Trip date Synchro Date BTL AreaOutage Cost

(crores)

Preceding Trip

date

SD Cause Outage hrsDay

Difference

1 226-04-2010

11:53

01-05-2010

05:15Mid RH 6.36

25-03-2010

23:03

Mid RH Tube

leakage136.92 32

2 105-05-2010

03:01

06-05-2010

17:58

Bottom

ring

header

2.4203-03-2010

19:13

Furnace Clinker

Formation216.58 62

3 116-06-2010

02:42

22-06-2010

12:48LTSH 8.82

03-06-2010

10:47

Replacement of

40116 Isolator

contactor

4.95 13

42

03-07-2010

07:13

06-07-2010

01:33

Economise

r4.12

13-05-2010

23:00

Furnace

pressure LL6.58

50

5 116-07-2010

18:10

21-07-2010

04:23LTSH 5.97

10-07-2010

13:28Coal Shortage 30.32 6

6 220-01-2011

22:48

23-01-2011

08:12LTSH 3.45

15-12-2010

13:38

DCS Power

Supply failure63.93 36

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BTL

NoUnit Trip date

Synchro

Date

BTL

Area

Outage

Cost

(crores)

Preceding Trip

dateSD Cause

Outage

hrs

Day

Difference

1 208-05-2011

23:26

13-05-2011

05:25LTSH 5.73

01-05-2011

00:54

Condenser

Tube Cleaning80.82 8

2 113-06-2011

13:17

16-06-2011

01:09

Water

Wall 3.29

22-05-2011

04:04

Low system

Demand24.079 22

23-05-2011

14:14

Drum level

sensor malfunction

6.417

2125-05-2011

21:59

1SB - 1PAB 6.6kV

Breaker Earth Fault

tripping

5.783 19

3

226-06-2011

20:41

01-07-2011

08:14

Water

Wall5.98

18-06-2011

19:04

DCS Communication

failure4.95 8

21-06-201110:45

415 V Busfailure

3 5

4 101-08-2011

17:09

05-08-2011

05:41LTSH 4.74

16-07-2011

20:05

Furnace pressure

LL6.583 16

5 221-11-2011

23:19

25-11-2011

14:21LTSH 5.07

27-10-2011

09:37Coal Shortage 144.4 26

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BTL

NoUnit

Trip

date

Synchro

Date

BTL

Area

Outage

Cost

(crores)

Preceding

Trip date

SD

Cause

Outage

hrs

Day

Difference

1 218-04-2012

23:51

22-04-2012

13:30

Near

IK 365.10

16-04-2012

09:58

FICF

pressure

low

3.23 3

2 125-04-2012

10:29

27-04-2012

16:06

Water

Wall3.25

10-03-2012

09:33

Exciter

Brush

failure

60.73 46

3 228-04-2012

21:30

03-05-2012

02:44LTSH 5.72

25-04-2012

15:54

Aux

power

failure

3.25 3

4 103-05-2012

12:43

06-05-2012

13:52LTSH 4.14

25-04-2012

10:29

BTL

Water

Wall

53.62 8

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MAKING BTL ZERO!!

REPLACEMENT OF WEAKENED TUBES / JOINTS AT

THE EARLIEST OPPORTUNITY, i.e. WHEN UNIT TRIPS

DUE TO SOME OTHER REASON

REGULAR MONITORING OF METAL TEMPERATURE

EXCURSION

REGULAR MONITORING OF METAL TEMPERATURE

AT LEAKAGE PRONE AREAS e.g. NEAR

SOOTBLOWERS

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THIS CALLS FOR AN ONLINE BOILER METAL

TEMPERATURE MONITORING SYSTEM THATWOULD ENABLE

24 X 7 BOILER TUBE METAL TEMPERATURE PROFILING

IDENTIFICATION OF TUBES ON THE VERGE OF

LEAKAGE.

ASLDs HELP ONLY AFTER THE TUBE LEAKAGE HAS

OCCURRED

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To lower fuel cost, we change coal sourcefrequently resulting in frequent changes in

fuel quality. Differences in fuel cause

combustion changes that affect slaggingand soot deposition in the furnace.

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The conventional sootblowing techniques relies

on employment of a large number of smaller

sootblowing systems, activated by the personaldiscretion of the control engineer rather than

activation based on measurements.

The problems associated with a fixed scheduleblowing system:

1) Excessive blowing wastes steam2) Insufficient blowing decreases efficiency

3) Unbalanced blowing may cause opacity

spikes.

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Fouling and slagging in the furnace as well as in the

convective heat exchanger zone leads to a reduction

in boiler efficiency and reduction in availability such

as:

1) Increase of furnace backend temperature

2) Increase of attemperation rate

3) Damages in the hopper area and the wet/dry

bottom ash system as a result of big slag formations

falling down from the furnace walls or/and

superheater.4) Unplanned boiler shut downs

5) Overcleaning damages tubes, affecting unit

availability

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FOULING IN FURNACE AREA

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ACCUMULATION OF COARSE ASH &

SLAG AT Bottom ash Hopper

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Therefore the solution is to blow appropriate

sections of the furnace as needed.

THIS CALLS FOR INTELLIGENT OR

SMART SOOTBLOWING SYSTEM

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SMART SOOTBLOWING LOGIC

source: EPRI

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BENEFITS OF SMART SOOTBLOWING

Reduction of tube erosion Reduction of usage of water

Reduction of attemperation spray rates

(extension of tube lifetime) Reduction of backend temperatures.