BOILER & CO-GENERATION

MAJOR CONTITUENTS

DM PLANTCOAL HANDLIING

PLANT

CO-GENERATION PLANT

ASH ANDLING PLANT

BOIILER

INTRODUCTION TO BOILER

ENCLOSED PRESSURE VESSEL

HEAT GENERATED BY COMBUSTION OF FUEL IS TRANSFERRED TO WATER TO BECOME STEAM

PROCESS: EVAPORATION

STEAM VOLUME INCREASES TO 1,600 TIMES FROM WATER AND PRODUCES TREMENDOUS FORCE

BOILER TO BE EXTREMELYDANGEROUS EQUIPMENT.CARE IS MUST TO AVOID

3What is a boiler?

COGENERATION PLANT VIEW

20 A

TA

11 A

TA

3.9

AT

A

11 A

TA

3.9

AT

A

CONDENSER

CONDENSER

5 BAR TO PROCESS

M

~

20 A

TA

~~

~

H.P.HTR

35 MW

6 MW

31.4 MW

5.6 MW

54 ATA COMMON HEADER

43 A

TA

HE

AD

ER

54 ATA COMMON HEADER

To Economiser

From BFP

B#4

150

TPH

Reynolds

Digestion 1, 3 & 4

B#3

140

TPH

B#2

80

TPH

B#1

80

TPH

~

Auxiliary Steam

4 BAR STEAM

6 MW

600/2

50

12 Bar

steam to

Dig-2

7 B

ar

Hdr

7 BAR TO PROCESS

250 PSI

from Hi-

Tech

COGENERATI

ON

PLANT•CO-GENERATION MEANS SIMULTANEOUSLY PRODUCTION OF POWER

& USEFUL THERMAL ENERGY FOR PROCESS FROM THE SAME

PRIMARY ENERGY SOURCE. AS PER MINISTRY OF POWER CO-

GENERATION IS DEFINED AS ONE WHICH SIMULTANEOUSLY

PRODUCES TWO OR MORE FORMS OF USEFUL ENERGY SUCH AS

ELECTRIC POWER AND STEAM, ELECTRIC POWER & SHAFT

(MECHANICAL) POWER ETC... IT ALSO DEFINES ANY FACILITY THAT

USES WASTE INDUSTRIAL HEAT FOR POWER GENERATION BY

SUPPLEMENTING HEAT, NOT MORE THAN 50%, FROM ANY FOSSIL

FUEL.

• AT HINDALCO WE ARE HAVING THE COGENERATION PLANT IN

WHICH WE USE THE STEAM FOR THE PROCESS REQUIREMENT AS

WELL AS POWER GENERATION

WHAT IS A BOILER

ANY CLOSED VESSEL EXCEEDING 22.75

LITRES IN CAPACITY WHICH IS USED

EXCLUSIVELY FOR GENERATING STEAM

UNDER PRESSURE INCLUDES ANY

MOUNTING AND OTHER FITTING

ATTACHED TO SUCH VESSEL WHICH IS

FULLY OR PARTIALLY UNDER PRESSURE

WHEN SHUTOFF

AUXILIARIES OF BOILER

FANS

INDUCED DRAFT

FAN

PRIMARY AIR FAN

FORCED DRAUGHT

FAN

ID FAN

• THE FUNCTION OF THIS FAN IS TO MAINTAIN THE DRAFT IN THE FURNACE AND CARAY OUT FLUE GAS OF THE FURNACE AND MAINTAIN THE NEGATIVE VALUE OF PRESSURE INSIDE THE FURNACE

PA FAN

• THE FUNCTION OF THIS FAN IS TO HEAT AND CARRY COAL FROM MILL TO THE FURNACE ( PULVERISHED COAL).

FD FAN

• THE FAN IS USED FOR THE PURPOSE OF SUPPLYING EXCESS AIR IN THE FURNACE FOR COMPLETE COMBUSTION OF COAL

AUXILIARIES OF BOILER

• The function of air preheater is to heat the incoming air from the Primary air fan which is supplied to the mills, Basically we are using this air as the medium for heating and conveying the Pulverized coal. The air preheater is located in the second pass of the Boiler and it gains its heat by the flue gases and gives the heat to the incoming air.

AIR PREHEATER

• The Economizer is the located in the second pass of the Boiler its function is to utilize the heat of flue gases coming out of the first pass of the Boiler which have done their work of producing steam from the Boiler. The economizer utilizes this heat of Flue gases which would otherwise be wasted to the atmosphere resulting in dry flue gas loss and reducing the efficiency of the Boiler.

ECONOMISER

AUXILIARIES OF BOILER

• The function of the mill is to grind the coal in the required size, like the size of coal required in the Pulverized fuel fired Boilers is of 75 microns so to achieve that size the mills are used. The mills used in the cogeneration plant are of Ball mill and Bowl mill type.

MILL

• The function of super heater is to superheat the Dry saturated steam coming from the drum and convert it into the superheated from so that chances of moisture is totally eliminated and the Enthalpy of steam is increased.

SUPERHEATERS

AUXILIARIES OF BOILER

• The function of the Electrostatic Precipitator is to collect the ash coming out of the Boiler and send it to the ash silo from where it is further utilized as per requirement. The ESP works on the principle of Corona where the Ash particles are charged by Direct Current and further collected at the collecting electrodes and than removed with the help of rappers and collected in the ash silos.

ESP

DETAILS OF BOILERS

12

BOILERS TYPE CAPACITY PR.

KG/CM2

TEMP. 0 C

YEAR OF

COMMISSI

ONING

MAKE

BOILER # 1 FRONT FIRING

(PF)80 (TPH) 52.5 450 1986 WIL PUNE

BOILER # 2 AFBC 80 (TPH) 52.5 450 1989BHEL,

TRICHI

BOILER # 3TANGENTIAL

FIRING (PF)140 (TPH) 111 535 1996

BHEL,

TRICHI

BOILER # 4TANGENTIAL

FIRING (PF)150 (TPH) 111 535 2004

BHEL,

TRICHI

STEAM GENERATION PER HOUR = 450 MT

STEAM RECEIVED FROM HI-TECH = 25-35 MT / HR

13

DM

water

Deaerat

or

BFP

Coal to

feeder

s by

Dozer

Coal

Convey

ors

Rotory

Coal

Feeder

s

Furnace

Coal

Transport

ing Line

Steam

Generati

on

Flue

Gas

to

ESP

PA

Fa

n

FD

Fa

n

Econo

miser

Water Circuit

Coal

YardCoal sizing circuit

for

-6mm size coal

Coal

Bunkers

ID Fan

Ash Recycling

feeder-2 No.

Steam to Power Plant /

Process

Exchange

of Heat

Energy

Feeder

Running

YES

Ash

Hopper

NOAsh

drain

Ash Recycling

feeder-2 No.

Process Flow of Boiler#2

FLUIDISED BED COMBUSTION BOILER

AFBC BOILER

15

•AFBC – ATMOSPHERIC FLUIDIZED BED

COMBUSTION

•DEFINITION

WHEN AIR OR GAS IS PASSED THROUGH AN

INERT BED OF SOLID PARTICLE SUCH AS SAND

OR CRUSHED REFRACTORY, THE AIR STARTS

BUBBLING THROUGH THE BED AND PARTICLE

ATTAIN A STATE OF HIGH TURBULENCE.

UNDER SUCH CONDITIONS, THE BED ASSUMES

THE APPEARANCE OF A FLUID AND EXHIBITS

THE PROPERTIES ASSOCIATED WITH A FLUID AND

HENCE THE NAME AFBC

FBC MECHANISM

16

IF THE BED MATERIAL IN FLUIDIZED

STATE IS HEATED TO THE IGNITION

TEMPERATURE OF THE FUEL AND

THE FUEL IS INJECTED CONTINUOUSLY

INTO THE BED, THE FUEL WILL BURN

RAPIDLY AND BED ATTAINS A

UNIFORM TEMPERATURE DUE TO

EFFECTIVE MIXING.

AFBC BOILER - ADVANTAGE

17

• FLEXIBLE IN THEIR ABILITY TO BURN A WIDE RANGE OF FUEL.

• DOES NOT REQUIRE OIL SUPPORT FOR START UP OR LOW LOAD

STABILIZATION.

• BY ADDING OF LIMESTONE IN THE BED STRINGENT SOX EMISSION

CONTROL IS POSSIBLE WITHOUT EXPENSING DOWN STREAM SCRUBBER

EQUIPMENT

• AUXILIARY POWER CONSUMPTION IS LOW.

• BETTER LOAD RESPONSE AND CAN BE VARIED FROM 20% TO 100% OF

NCR.

• LESS INITIAL COST.

• EASY IN OPERATION.

• C & I REQUIREMENT FOR FBC ARE MINIMAL. NO BMS REQUIRED

AFBC BOILER - DISADVANTAGE

18

• SUITABLE FOR LOW AND MEDIUM CAPACITY ONLY.

• MORE MAINTENANCE COST DUE TO HIGH

EROSION OF TUBES.

• LOWER EFFICIENCY.

• MORE EFFORTS REQUIRED WHEN IT IS INITIALLY

START UP WITH CHARCOAL.

FUEL FEEDING SYSTEM

19

•Fuel is evenly distributed by judicious location of feed points for burning

most of the volatiles and carbon within the bed and to avoid localized fuel

concentration

Comp-1Comp-2Comp-3Comp-4

Coal feed pointsRecycle ash feed

pointsDistributor plates

AIR DISTRIBUTION

20

•PROPER AIR DISTRIBUTOR IS REQUIRED TO ENSURE UNIFORM

DISTRIBUTION OF AIR ACROSS BED CROSS SECTION

Comp-1Comp-2Comp-3Comp-4

Nozzles are provided across the bed for proper air distribution

BED TEMPERATURE & HEIGHT

21

•BED TEMPERATURE: - FBC NORMALLY

OPERATES AT A TEMPERATURE RANGE

750-950º C FOR COAL

• BED HEIGHT: - DETERMINED BY THE NEED TO

SUBMERGE HEAT EXCHANGER TUBES AND IN CASE OF

HIGH SULPHUR COAL THE VOLUME REQUIREMENT FOR

EFFECTIVE SULPHUR CAPTURE

FOR MOST OF THE INDIAN FUELS A SHALLOW BED LESS

THAN 1000 MM IS ADEQUATE.

BED TEMPERATURE & HEIGHT

22

Water

Heade

r

Air from FD Fan

Coal Transporting

Line

Primar

y Air

Bed material

in Fluidization

state

BLOCK DIAGRAM OF AFBC BOILER

24

TECHNICAL DATA

25

SN PARAMETER UNIT CAPACITY

1 Heating Surface M² 3426.9

2 Steam Flow TPH 80

3 Steam Pressure Kg/Cm

²52.5

4 Steam Temperature Deg C 450±5

5 Feed Water Temp. Deg C 105

6 Fluidized Air Temp Deg C 130

7 Boiler Efficiency % 82±1.5

Coal Size: -(-) 6 mm to Furnace with maximum 20% fines

26

Boiler Flue gas

Steam Output

Efficiency = 100 – (1+2+3+4+5+6+7+8)

(by In Direct Method)

Air

Fuel Input, 100%

1. Dry Flue gas loss

2. H2 loss

3. Moisture in fuel

4. Moisture in air

5. CO loss

7. Fly ash loss

6. Surface loss

8. Bottom ash loss

WHAT ARE THE LOSSES THAT OCCUR

IN A BOILER?

27

INTERMITTENT

BLOWDOWN

• THE INTERMITTENT BLOWN DOWN IS GIVENBY MANUALLY OPERATING A VALVE FITTEDTO DISCHARGE PIPE AT THE LOWEST POINTOF BOILER SHELL TO REDUCE PARAMETERS(TDS OR CONDUCTIVITY, PH, SILICA ETC)WITHIN PRESCRIBED LIMITS SO THATSTEAM QUALITY IS NOT LIKELY TO BEAFFECTED

• TDS LEVEL KEEPS VARYING

• FLUCTUATIONS OF THE WATER LEVEL INTHE BOILER.

• SUBSTANTIAL AMOUNT OF HEAT ENERGY ISLOST WITH INTERMITTENT BLOW DOWN.

28

•WHEN WATER EVAPORATES

•DISSOLVED SOLIDS GETS

CONCENTRATED

•SOLIDS PRECIPITATES

•COATING OF TUBES

•REDUCES THE HEAT TRANSFER

RATE

Why Boiler Blow Down ?

PULVERIZED FIRE BOILER SKETCH

PULVERIZED FUEL BOILER

30Tangential firing

Coal is pulverised to a fine powder, so that less than 2% is +300microns, and 70-75% is below 75 microns.

Coal is blown with part of the combustion air into the boiler plantthrough a series of burner nozzles.

• Combustion takes place attemperatures from 1300-1700°C

• Particle residence time in theboiler is typically 2-5 seconds

• One of the most popular systemfor firing pulverized coal is thetangential firing using fourburners corner to corner tocreate a fire ball at the center ofthe furnace.

ADVANTAGES

ITS ABILITY TO BURN ALL RANKS OF COAL FROMANTHRACITIC TO LIGNITE, AND IT PERMITSCOMBINATION FIRING (I.E., CAN USE COAL, OILAND GAS IN SAME BURNER). BECAUSE OFTHESE ADVANTAGES, THERE IS WIDESPREADUSE OF PULVERIZED COAL FURNACES.

DISADVANTAGES

HIGH POWER DEMAND FOR PULVERIZING

REQUIRES MORE MAINTENANCE, FLY ASHEROSION AND POLLUTION COMPLICATE UNITOPERATION.

31

Pulverized Fuel Boiler

32

PULVERIZED

FUEL

FIRING

FUELS SYSTEM IN PF BOILER#1

33

BALL MILL:-

• IT IS FRONT WALL FIRED PULVERIZED FUEL BOILER HAVING

FOUR BURNERS ON FRONT WALL.

• BOILER NO. 1 IS PULVERIZED FUEL BOILERS.

• OIL GUNS IS PROVIDED FOR START UP AND SUPPORT AT TWO

LEVELS.

• MINUS 20 MM SIZE COAL IS FED TO THE MILL THROUGH THE

TWO NUMBER VOLUMETRIC COAL FEEDERS.

AS THE MILL ROTATES, THE COAL IN THE MILL IS PULVERISED

BY THE CRUSHING AND GRINDING ACTION OF CASCADING

STEEL BALLS. PREHEATED AIR WHICH COMES FROM PRIMARY

AIR FAN, AND FUEL MIXTURE, AFTER PASSING THROUGH THE

CLASSIFIERS, ENTERS THE COAL CONDUITS AND PASSES ON

TO THE BURNERS. THE OUTPUT OF THE MILL SYSTEM FOR A

BALL MILL OF PF BOILER#1

34

FUELS SYSTEM IN PF BOILER#3 &

4

35

BOILER NO. 3 & 4 IS TANGENTIAL FIRED

PULVERIZED FUEL BOILER HAVING FOUR

ELEVATION BURNERS.

IN EACH ELEVATION FOUR COAL BURNER ARE

AVAILABLE.

FOUR NUMBER BOWL MILLS ARE THERE TO CRUSH

THE 20 MM SIZE COAL. OUT OF THESE FOUR MILLS,

THREE MILLS SHOULD BE IN SERVICE FOR FULL

STEAM LOAD.

BOWL AND ROLLERS ARRANGEMENTS ARE THERE

TO CRUSH THE 20-MM SIZE COAL INSIDE THE MILL.

HOT AIR FROM AIR PREHEATERS SUCKED BY THE

EXHAUSTER OF RUNNING BOWL MILL CARRIES

QUALITY OF COAL

36

Coal Feed Size

BOILER #1, 3 & 4: 100% (-) 20 MM TO MILL

70% (-) 200 MESH TO

FURNACE

BOILER#2 : (-) 6 MM WITH 20% FINES TO

FURNACE

MOISTUREVOLATILE

MATTERASH

FIXED

CARBON

CALORIFIC

VALUE

10%-16% 21%-26% 35%-38% 25%-30%2900-3500

KCAL/KG

Proximate Analysis

Values

37

. REDUCE STACK TEMPERATURE22O C REDUCTION IN FLUE GAS TEMPERATURE INCREASES BOILER

EFFICIENCY BY 1%

. COMBUSTION AIR PREHEATING

. FEED WATER PREHEATING USING

ECONOMIZER6OC RAISE IN FEED WATER TEMPERATURE, BY ECONOMISER/CONDENSATE

RECOVERY, CORRESPONDS TO A 1% SAVING IN FUEL CONSUMPTION

IN ORDER TO IMPROVE THERMAL EFFICIENCY BY 1%, THE COMBUSTION AIR

TEMP. MUST BE RAISED BY 20 DEG C.

ENERGY CONSERVATION

OPPORTUNITIES IN BOILER

. INCOMPLETE COMBUSTION

38

Energy Conservation Opportunities in

Boiler

. CONTROL EXCESS AIR

For every 1% reduction in excess air ,0.6% rise in efficiency.

. RADIATION AND CONVECTION HEAT

LOSS

. AUTOMATIC BLOWDOWN CONTROL

. REDUCTION OF SCALING AND

SOOT LOSSES

. REDUCTION OF BOILER STEAM

PRESSURE

Performance of a Boiler

hg -the enthalpy of saturated steam in kcal/kg of steam

hf -the enthalpy of feed water in kcal/kg of water

Boiler Efficiency: Direct Method

Boiler efficiency () =Heat output

Heat inputx 100 Q sx (hg – hf)

Q x GCVx 100=

PARAMETERS TO BE MONITORED:

- QUANTITY OF STEAM GENERATED PER HOUR (QS) IN KG/HR

- QUANTITY OF FUEL USED PER HOUR (Q) IN KG/HR

- THE WORKING PRESSURE (IN KG/CM2(G)) AND SUPERHEAT

TEMPERATURE (OC), IF ANY

- THE TEMPERATURE OF FEED WATER (OC)

- TYPE OF FUEL AND GROSS CALORIFIC VALUE OF THE FUEL

(GCV) IN KCAL/KG OF FUEL

DM PLANT

THE WATER TO BE FEED IN BOILER FOR STEAM GENERATION MUST BE DEMINERALISED AS PER SHOULD NOT CONTAIN ANY DISSOLVED SOLID SUCH AS SILICA OR CHLORIDES AND CARBONATES WHICH RESULTS IN SLUDEFE FORMATION AND SCALE FORMATION IN THE BOILER RESULTING IN LOW EFFICIENCY OF BOILER ,LOW RATE OF STEAM GENERATION AND WASTAGE AND MORE CONSUMPTION OF FUEL ACCOMPANING WITH CORROSION OF INER BODY SURFACE OR CAN SAY METAL OF BOILER BODY .

SO FOR THIS PURPOSE WATER HAS TO BE TREATED FIRST AND SHOULD MAINTAIN TDS(TOTAL DISSOLVED SAOLID)AS LOW AS POSSIBLE BY PROPER TREATMENT .

DM PLANT

PUMP

PUMP

AIR BLOWER

PUMP FLOW CHART OF D. M. PLANT

CW

TANK

DYNA-

-SAND

FILTE

R

M G F

A C F

S A C DEGASSED

WATER

TANK

S B A

COLD DM

TANK

F W

TANK

DEMINERALIZATION OF WATER

• THE PROCESS OF DEMINERALIZATION RESULTS IN REMOVAL

OF MINERALS FROM WATER,.

CLEAR WATER IS RECEIVED FROM CLEAR WATER TANK AND THE

MONITORING OF PH (9.7-10.2) AND CONDUCTIVITY (BELOW 150

MICRO SIEMENS/CM) ON DAILY BASIS IS MADE.

DYNA SAND

FILTER• SINGLE FILTER OF SAND SIZE 0.9 MM .ITS BASIC FUNCTION IS

TURBIDITY REMOVAL, INLET TURBIDITY TO THE FILTER IS 200PPM

AND OUTLET TURBIDITY IS LESS THAN 5 PPM ,ALUM DOSING IS

ALSO

DONE IN THIS FILTER.

MULTI GRATE FILTER

•THIS IS USED FOR THE REMOVAL OF TURBIDITY THE INLET

TURBIDITY

IS 40 PPM AND OUTLET TURBIDITY LESS THAN 5 PPM AT

PRESENT

WE ARE GETTING (0-1) NTU.

ACTIVATED

CARBON

FILTER•THIS IS USED TO ABSORB EXCESS CHLORINE, REMOVAL OF

ORGANIC MATTER AND OIL & GREASE IF ANY. AND CHARCOAL

IS

USED AS ACTIVATED CARBON IN THE ACTIVATED CARBON

FILTER.

STRONG ACID CATION

•THE STRONG ACID CATION RESIN EXCHANGES ALL CATION IN

WATER, THE CATION ASSOCIATED WITH ALKALINITY OR THOSE

COMBINED AS NEUTRAL SALTS ALL ARE REMOVED BY SAC RESIN.

I T HAS A GREATER AFFINITY FOR DIVALENT ION THAN THE

MONOVALENT ION AS A RESULT SELECTIVITY OF CA AND MG IS

MORE THAN FOR NA CONSEQUENTLY THE FRONT PORTIONS OF THE

RESIN BED ARE PREDOMINANT WITH CA & MG, WHILE NA GOES

TO THE TAIL SECTION OF THE RESIN BED AND SO THE NA ION SLIP

OUT OF CATION EXCHANGER DUE TO REGENERATIVE EFFECT OF

FREE

MINERAL ACID

DEGASSER

•IT IS USED FOR CARBON DIOXIDE REMOVAL . CARBONIC ACID

GENERATED IN SAC UNIT IS DECOMPOSED IN WATER+ CARBON

DIOXIDE AND IT ESCAPES OUT FROM THE TOP OF DEGASSER BY

DEGASSER BLOWER , MAXIMUM 6 PPM OF CO2 IS ALLOWED

AFTER DEGASSER UNIT.

STRONG BASE

ANION•SBA RESIN HAS GREATER AFFINITY FOR

IONIC SPECIES, SULFATE AND CHLORIDE THAN FOR THE MOLECULAR

CARBON DIOXIDE AND SILICA AND HIGHER SELECTIVITY FOR

SULFATE ION THAN CHLORIDE ION. AGAIN THERE IS DISTRIBUTION

OF CONTAMINANTS OVER THE RESIN BED WITH FRONT LAYER HIGH

IN SULFATE FOLLOWED BY CHLORIDE AND CARBON DIOXIDE AND

THE SILICA AT TAIL END OF THE BED.

MIXED BED

•THE MIXED BED DEMINERALIZATION PROCESS

CONSISTS OF SAC AND SBA RESIN INTIMATELY MIXED TO

BRING ABOUT THE DEMINERALIZATION OF WATER, IN EFFECT IT IS

MULTIPLE AND RANDOM TWO BED DEMINERALIZATION PAIRS

RESULTING IN VERY HIGH QUALITY OF DM WATER . HERE THE

LEAKAGE OF IONS CAUSED BY THE REGENERATING EFFECT OF

FMA OR OF NAOH FORMED IN THE EXCHANGING PROCESS IS

ABSENT ,THIS IS BECAUSE FMA GENERATED BY SAC RESIN IS

EXCHANGED BY NEIGHBORING SBA RESIN LIKE WISE NAOH

GENERATED BY SBA RESIN IS EXCHANGED BY ADJACENT SAC

RESIN .CATION RESIN IS HEAVIER THAN THE SBA RESIN SO

CATION FORMS THE DOWN LAYER . THE PARAMETERS AT THE

OUTPUT ARE PH-6 TO7,CONDUCTIVITY 2 MICRO SIEMENS/CM,

SILICA 0.02MG/LTR.

COAL

HANDLING

PLANT

coal yard

_

2

0

m

m

_

_

2

o

_

2

o

BOILER # 1 & 2 BUNKER FLOOR

Bunker

Boiler # 1

Bunker

Boiler # 2

Bunker

Boiler # 3

Tripper

Tripper Conveyor

BOILER # 3 BUNKER FLOOR

Tripper

Trolley Tripper Conveyor

Conveyor No. 64

Reciprocating Feeder 1or 2

Reclain Conveyor

BC - 11831

To Old Circuit #1,#3 To Old Circuit # 2

Vibro Feeder Vibro Feeder

Impactor '+ / -' 6

mm'

Vibrating Screen

Impactor

-20mm Vibro Feeder

Vibrating Screen

'- 6 mm'

Coal

'+6 mm' Coal

'+20 mm' Coal

'Bucket E

levato

r

Daybin Conveyor

BC - 33830

Conveyor - 70

Conveyor - 69

Conveyor - 65

Cross Conveyor

NEW COAL CIRCUIT - FLOW CHART (COAL PLANT)

Triveni / P.K.Sharma/ Sheet 1

'- 20 mm' Coal

COAL PLANT OPERATION

•COAL IS UNLOADING FROM WAGON TIPPLER IN TWO SIZES I E: -

01. +25 MM AND –75 MM (ABOVE 25MM AND BELOW 75 MM)

02. –25 MM AND + 75MM (BELOW 25MM AND ABOVE 75MM)

• AFTER UNLOADING OF COAL WE FED THE DIFFERENT SIZE COAL

IN DIFFERENT BOILERS. WE HAVE FOUR BOILERS. THREE ARE PF

AND ONE IS FBC. IN PF BOILER WE HAVE USE THE COAL BELOW

THE 20MM. IN FBC BOILER WE HAVE USE THE COAL BELOW THE

6MM.FOR, WHICH VARIOUS EQUIPMENTS HAVE BEEN INSTALLED

IN COAL PLANT AREA.•TO FEED THE COAL IN PF BOILERS (B#1,3 &4) PUSH THE COAL BY

DOZERS IN ROTORY FEEDERS GRIZZLY SITUATED IN COAL YARDS.

COAL IS COMING FROM RECLAIM CONVEYER TO CONVEYER#64,

THEN VIBRATING SCREEN HAVING SIZE OF 20MM THROUGH VIBRO

FEEDER. LESS THAT 20 MM COAL HAVE FALLEN THROUGH SCREEN

DIRECTLY TO CONVEYER#70 AND OVERSIZE COAL GOING TO

CONVEYER#70 THROUGH COAL IMPACTOR HAVING CAPACITY 120

TPH. FINALLY COAL IS GOING TO THE BUNKERS OF BOILER#1,3&4

THROUGH COMVEYER#70, DAYBIN CONVEYER AND TRIPPER

CONVEYER.

•TO FEED THE COAL IN FBC BOILER (B#2) PUSH THE COAL BY

DOZERS IN ROTARY FEEDERS GRIZZLY SITUATED IN COAL

YARDS. COAL IS COMING FROM RECLAIM CONVEYER TO

CONVEYER#64, VIBRO FEEDER THEN COAL IMPACTOR

(240TPH) TO TWO NUMBERS VIBRATING SCREENS HAVING

CAPACITY OF 120 TPH EACH THROUGH TWO VIBRO FEEDERS.

COAL HAS FALLEN THROUGH SCREEN DIRECTLY TO

CONVEYER#69(SIZE LESS THAT 6MM) AND OVERSIZE COAL

(ABOVE 6MM) GOING TO CONVEYER#64 THROUGH BUCKET

ELEVATOR HAVING CAPACITY 65 TPH FOR RECRUSHING IN

COAL IMPACTOR WITH FRESH COAL. CLOSE COAL CIRCUIT IS

RUNNING DURING COAL FEEDING IN B#2. FINALLY COAL IS

GOING TO THE BUNKERS THROUGH COMVEYER#70, DAYBIN

CONVEYER AND TRIPPER CONVEYER.

CHP

FLOW CHART

FLOW DIAGRAM FOR COAL HANDLING PLANT

Through Feeder Through Feeder

YES

NO NO

Wagon Tippler (Crushed to less than 100 mm

size)

Newton In Motion Weighbridge for Weigment of wagons

C

a

o

l

f

r

o

m

C

o

l

l

i

e

r

i

e

s

S

i

z

e

:

-

L

e

s

s

t

h

a

n

5

0

0

m

m

100mm to 75mm and

less than 25mm size coal

collected in & out side the

coal shed for Boiler#1 &

3

75mm to 25mm size

coal collected in

side the coal shed

for Boiler#2

Reclaim Conveyor

Conveyor#64

Vibro Feeder (W)

For Boiler#1 & 3(51)

Vibro Feeder (E)

For Boiler#2(48)

Boiler#1 & 3 Coal

Impactor (100

-

2

0

m

m

s

i

z

e

Boiler#2 Coal Impactor

(240 MT/HR)

-

8

m

m

s

i

z

e

B

U

C

K

E

T

E

L

E

V

A

T

B

u

n

k

e

r

s

t

o

f

i

l

l

Conv#

65

Vibro fdr#49 Vibro fdr#50

51