NTPC Sippat 3X660 MW.pdf

8/13/2019 NTPC Sippat 3X660 MW.pdf

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POINTS OF DISCUSSION

SUB CRITICAL & SUPER CRITICAL BOILER

SIPAT BOILER DESIGN

BOILER DESIGN PARAMETERS

CHEMICAL TREATMENT SYSTEM

OPERATION FEED WATER SYSTEM

BOILER CONTROL

BOILER LIGHT UP

START UP CURVES


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To Reduce emission for each Kwh of electricity generated : Superior Environmental

1% rise in efficiency reduce the CO2 emission by 2-3%

The Most Economical way to enhance efficiency

To Achieve Fuel cost saving : Economical

Operating Flexibility

Reduces the Boiler size / MW

To Reduce Start-Up Time

WHY SUPER CRITICAL TECHNOLOGY


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Water when heated to sub critical pressure, Temperature increases until itstarts boiling

This temperature remain constant till all the water converted to steam

When all liquid converted to steam than again temperature starts rising.

Sub critical boiler typically have a mean ( Boiler Drum) to separate Steam And

Water

The mass of this boiler drum, which limits the rate at which the sub critical

boiler responds to the load changes

Too great a firing rate will result in high thermal stresses in the boiler drum

UNDERSTANDING SUB CRITICAL TECHNOLOGY


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Role of SG in Rankine Cycle

Perform Using Natural resources of energy .


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Circulation Vs Once Through


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No Religious Attitude


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540C 255 Ksc


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HPT

IPTLPTC

O

N

D

E

N

S

E

R

FEEDWATER

FRS

S

T

O

R

A

G

E

T

A

N

K

SEPARATOR

BWRP

MS LINE

HRH LINE

VERTICAL WW

ECO I/L

ECO

JUNCTION

HDR

ECO HGR

O/L HDR

FUR LOWER HDR

FUR ROOF

I/L HDR

DIV PANELS SH PLATEN

SH

FINAL

RH

FINAL SH

LTRH

ECONOMISER

290C, 302 KSC

411C,

277Ksc

411C,

275 Ksc

492C, 260 Ksc

540C, 255 Ksc

305C,

49Ksc

457C, 49 Ksc

568C, 47Ksc

GLPT


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SIPAT SUPER CRITICAL BOILER

BOILER DESIGN PARAMETER

DRUM LESS BOILER : START-UP SYSTEM

TYPE OF TUBE

Vertical

Spiral

SPIRAL WATER WALL TUBING

Advantage

Disadvantage over Vertical water wall


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Vertical Tube Furnace

To provide sufficient flow per tube, constant pressure furnaces

employ vertically oriented tubes.

Tubes are appropriately sized and arranged in multiple passes in

the lower furnace where the burners are located and the heat input

is high.

By passing the flow twice through the lower furnace periphery

(two passes), the mass flow per tube can be kept high enough to

ensure sufficient cooling.

In addition, the fluid is mixed between passes to reduce the upset

fluid temperature.


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Spiral Tube Furnace

The spiral design, on the other hand, utilizes fewer tubes to obtain

the desired flow per tube by wrapping them around the furnace to

create the enclosure.

This also has the benefit of passing all tubes through all heat

zones to maintain a nearly even fluid temperature at the outlet ofthe lower portion of the furnace.

Because the tubes are wrapped around the furnace to form the

enclosure, fabrication and erection are considerably morecomplicated and costly.


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BOILER OPERATING PARAMETERFD FAN 2 NoS( AXIAL ) 11 kv / 1950 KW 228 mmwc

1732 T / Hr

PA FAN 2 Nos ( AXIAL) 11 KV / 3920 KW 884 mmwc

947 T / Hr

ID FAN 2 Nos ( AXIAL) 11 KV / 5820 KW 3020 T / Hr

TOTAL AIR 2535 T / Hr

SH OUT LET PRESSURE / TEMPERATURE /FLOW

256 Ksc / 540 C2225 T / Hr

RH OUTLET PRESSURE/ TEMPERATURE /

FLOW

46 Ksc / 568 C

1742 T / Hr

SEPARATOR OUT LET PRESSURE/

TEMPERATURE

277 Ksc / 412 C

ECONOMISER INLET 304 Ksc / 270 C

MILL OPERATION 7 / 10

COAL REQUIREMENT 471 T / Hr

SH / RH SPRAY 89 / 0.0 T / Hr

BOILER EFFICIENCY 87 %


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1. High erosion

potential forpulverizer andbackpass tube isexpected due tohigh ash content.

2. CombustibilityIndex is relativelylow butcombustioncharacteristic isgood owing tohigh volatilecontent.

Parameter Unit

Design

Coal

Worst

Coal

Best

Coal

Young Hung

#1,2(800MW)

Tangjin

#5,6(500MW)

High Heating Value kcal/kg 3,300 3,000 3,750 6,020 6,080

Total Moisture % 12.0 15.0 11.0 10.0 10.0

Volatile Matter % 21.0 20.0 24.0 23.20 26.53

Fixed Carbon % 24.0 20.0 29.0 52.89 49.26

ProximateAnalysis

Ash % 43.0 45.0 36.0 13.92 14.21

Fuel Ratio (FC/VM) - 1.14 1.00 1.21 2.28 1.86

Combustibility Index - 2,067 2,353 2,476 2,781 3,492

Carbon % 39.53 31.35 40.24 63.03 62.15

Hydrogen % 2.43 2.30 2.68 3.60 3.87

Nitrogen % 0.69 0.60 0.83 1.53 1.29

Oxygen % 6.64 5.35 8.65 7.20 7.80

Sulfur % 0.45 0.40 0.60 0.72 0.68

Ash % 43.00 45.00 36.00 13.92 14.21

UltimateAnalysis

Moisture % 12.00 15.00 11.00 10.00 10.00

Grindability HGI 50 47 52 45 48

ASTM Coal Classification -HiVol. CBituminous

HiVol. CBituminous

HiVol. CBituminous

Midium Vol.Bituminous

HiVol. CBituminous

Coal Analysis


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1. Lower

slagging

potential is

expected due

to low ash

fusion temp.

and low basic

/ acid ratio.

2. Lower fouling

potential is

expected due

to low Na2O

and CaO

content.

Parameter UnitDesign

CoalWorstCoal

BestCoal

Young Hung#1,2(800MW)

Tangjin#5,6(500MW)

SiO2 % 61.85 62.40 61.20 57.40 57.40

Al2O3 % 27.36 27.31 27.32 29.20 29.20

Fe2O3 % 5.18 4.96 5.40 4.40 4.40

CaO % 1.47 1.42 1.52 2.70 2.70

MgO % 1.00 1.03 0.97 0.90 0.90

Na2O % 0.08 0.08 0.08 0.30 0.30

K2O % 0.63 0.32 1.22 0.70 0.70

TiO2 % 1.84 1.88 1.80 1.30 1.30

P2O5 % 0.54 0.55 0.44 - -

SO3 % 0.05 0.05 0.05 - -

Ash

Analysis

Others % - - - 3.10 3.10

Initial Deformation oC 1150 1100 1250 1200 1200

Softeningo

C - - -Hemispheric oC 1400 1280 1400

Ash Fusion

Temp. (o

C)(Reducing

Atmos.) Flow oC 1400 1280 1400

Ash Content kg/Gcal 130.3 150.0 96.0 23.12 23.37

Basic / Acid B/A 0.09 0.09 0.10 1.63 1.63

Ash Analys is


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AIR AND FLUE GAS SYSTEM

AIR PATH : Similar as 500 MW Unit

FLUE GAS PATH:

No Of ESP Passes : 6 Pass

No Of Fields / Pass : 18

No Of Hopper / Pass : 36

Flue Gas Flow / Pass : 1058 T/ Hr

1-7 fields 70 KV.

8&9 field 90 KV


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RHS WIND BOX

BACK PASS

FURNACE

M

M

M

M

M

M M

M

M M

M

M M

M

M M

M

M

M

M

PAPH # A

SAPH # A

PAPH # B

SAPH # B

M AIR MOTOR

M AIR MOTOR

M AIR MOTOR

M AIR MOTOR

M

HOT PRIMARY AIR DUCT

HOT PRIMARY AIR DUCT

TO PULVERISER SYSTEM

TO PULVERISER SYSTEM

M

M

M

M

M

M

M

DIVISIONALPANEL

PLATENCOILS

FINALREHEATER

FINALSUPERHEATER

LTRH

ECONOMISER

LHS WIND BOX

PA FAN # A

FD FAN # A

FD FAN # B

PA FAN # B

AIR PATH


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FUEL OIL SYSTEM

Type Of Oil : LDO / HFO

Boiler Load Attainable With All Oil Burner In Service : 30 %

Oil Consumption / Burner : 2123 Kg / Hr

Capacity Of HFO / Coal : 42.1 %

Capacity Of LDO / Coal : 52.5 %

HFO Temperature : 192 C

All Data Are At 30 % BMCR


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DESIGN BASIS FOR SAFETY VALVES :

1. Minimum Discharge Capacities.

Safety valves on Separator and SH Combined capacity 105%BMCR

(excluding power operated impulse safety valve)

Safety valves on RH system Combined capacity 105% of Reheat

flow at BMCR

(excluding power operated impulse safety valve)

Power operated impulse safety valve 40%BMCR at super-heater outlet

60% of Reheat flow at BMCR at RH

outlet

2. Blow down 4% (max.)b


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BOILER FILL WATER REQUIREMENT

Main Feed Water Pipe ( FW Shut Off Valve to ECO I/L HDR) 28.8 m3

Economizer 253.2 m3

Furnace ( Eco Check Valve to Separator Link) 41.5 m3

Separators & Link 13.8 m3


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All Volatile

Treatment

OxygenatedWater

Treatment

DOSING POINTS


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DOSING POINTS

AVT Dosing Auto Control


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AVT Dosing Auto Control

OWT Dosing Auto Control


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OWT Dosing Auto Control


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FUR ROOF I/L HDR U # 1


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BACK PASS ECO I/L HDR

BACK PASS ECO O/L HDR

1 2 1 2 1 2 1 2

BRP

TO DRAIN HDR

FROM FEED WATER

BLR FILL PUMP

N2 FILL LINE

VENT HDR

DRAIN HDR

DRAIN HDR

VENT HDR

VENT HDR

N2 FILL LINE

SAMPLE COOLER SAMPLE COOLER

N2 FILL LINE

VENT HDR

VENT HDR

ECO MIXING LINKECO JUNCTION HDR

FUR BOTTOM RING HDR

FUR INTERMITTENT HDR

FUR WW HDR

SEPRATOR #1 SEPRATOR #2

STORAGE TANK

MIXING PIECE

FLASH TANK

WR ZR

WATER LINE

N2 FILLING LINE

VENT LINE

DRAIN LINE

SAMPLE COOLER LINE

WATER CIRCULATION SYSTEM

FEED WATER SYSTEM


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MODES OF OPERATION

1. BOILER FILLING

2. CLEAN UP CYCLE

3. WET MODE OPERATION (LOAD < 30 % )

4. DRY MODE OPERATION (LOAD > 30 %)

5. DRY TO WET MODE OPERATION ( WHEN START UP SYSTEM NOT AVAILABLE)

FEED WATER SYSTEM

BOILER FILLING LOGIC


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If the water system of the boiler is empty (economizer, furnace walls, separators),

then the system is filled with approximately 10% TMCR ( 223 T/Hr) feed water flow.

When the level in the separator reaches set-point, the WR valve will begin to open.

When the WR valve reaches >30% open for approximately one minute, then

increase feed water flow set-point to 30% TMCR ( approx 660 T/Hr).

As the flow increases, WR valve will reach full open and ZR valve will begin toopen.

The water system is considered full when:

The separator water level remains stable for two(2) minutes

and The WR valve is fully opened and ZR valve is >15% open for two(2)

minutes

After com plet ion o f Fi ll ing, the feed water f low is again adju sted to 10 % TMCR for

Clean up cycle op erat ion

BOILER FILLING LOGIC

BOILER INITIAL WATER LEVEL CONTROL (UG VALVE)


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The boiler circulating pump is started following the start of a feed water

pump and the final clean-up cycle.

This pump circulates feed water from the evaporator outlet back to the

economizer inlet.

Located at the outlet of this pump is the UG valve which controls

economizer inlet flow during the start-up phase of operation.

Demand for this recirculation, control valve is established based on

measured economizer inlet flow compared to a minimum boiler flow set

point.

BOILER INITIAL WATER LEVEL CONTROL (UG VALVE)


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Boiler Clean-up

When the feedwater quality at the outlet of deaerator and separator is not

within the specified limits, a feedwater clean-up recirculation via the boiler is

necessary.

During this time, constant feedwater flow of 10% TMCR ( 223 T/Hr) or more

is maintained.

Water flows through the economizer and evaporator, and discharges the

boiler through the WR valve to the flash tank and via connecting pipe to the

condenser.

From the condenser, the water flows through the condensate polishing

plant, which is in service to remove impurities ( Like Iron & its Oxide, Silica,

Sodium and its salts ), then returns to the feed water tank.

The recirculation is continued until the water quality is within the specified

limits.


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FEED WATER QUALITY PARAMETER FOR START UP

MODE OF OPERATION


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MODE OF OPERATION

WET MODE :

Initial Operation Of Boiler Light Up. When Economizer Flow is maintained by

BCP.

Boiler Will Operate till 30 % TMCR on Wet Mode.

DRY MODE :

At 30 % TMCR Separator water level will become disappear and Boiler

Operation mode will change to Dry

BCP Will shut at this load

Warm Up system for Boiler Start Up System will get armed

Boiler will turn to once through Boiler

ECO Water flow will be controlled by Feed Water Pump in service

SYSTEM DESCRIPTION ( WET MODE OPERATION)


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1. Flow Control Valve ( 30 % Control Valve )

Ensures minimum pressure fluctuation in Feed Water Header

It measures Flow at BFP Booster Pump Discharge and compare it with a calculated flowfrom its downstream pressure via a function and maintains the difference 0

2. 100 % Flow Valve To Boiler

Remains Closed

3. BFP Recirculation Valve

It Measures Flow at BFP Booster Pump Discharge

Ensures minimum Flow through BFP Booster Pump

Closes when Flow through BFP Booster Pump discharge > 2.1 Cum

Open When Flow through BFP Booster Pump Discharge < 1.05 Cum

( Minimum Flow will be determined by BFP Speed via BFP Set limitation Curve)

4. BFP Scoop

It measures value from Storage tank level Transmitter

Maintain Separator Storage Tank Level

SYSTEM DESCRIPTION ( WET MODE OPERATION)


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SYSTEM DESCRIPTION ( DRY MODE OPERATION)


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SYSTEM DESCRIPTION ( DRY MODE OPERATION)

1. Following System will be isolated during Dry Mode Operation

FCV ( 30 % )

Start Up System Of Boiler

WR / ZR Valve

Storage Tank

BRP

BRP Recirculation System

BFP Recirculation Valve

2. Following System will be in service

UG Valve ( Full Open)

100 % FW Valve ( Full Open)

Platen / Final Super-heater spray control

Start Up System Warming Lines

Separator Storage Tank Wet Leg Level Control

SYSTEM OPERATION ( DRY MODE OPERATION)


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( )

1. START UP SYSTEM

In Dry Mode Start Up System Of Boiler will become isolated

Warming System for Boiler Start Up system will be charged

Separator Storage Tank level will be monitored by Separator storage tank wet leg level

control valve ( 3 Mtr)

2. TRANSITION PHASE :- Changeover of FW Control valve (30 % to 100 % Control )

100 % FW Flow valve will wide open

During the transition phase system pressure fluctuates

The system pressure fluctuation will be controlled by 30 % FW Valve. After stabilization of

system 30 % CV Will become Full Close

3. FEED WATER CONTROL

It will be controlled in three steps

Feed Water demand to maintain Unit Load

Maintain Separator O/L Temperature

Maintain acceptable Platen Spray Control Range


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FEED WATER DEMAND ( DRY MODE OPERATION)


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2. FEED BACK DEMAND

Work With two controller in cascade mode

FIRST CONTROLLER

One Controller acts on Load dependent average platen spray differential

temperature

Its Output represents the desired heat transfer / steam generation to maintain

the desired steam parameters and Flue gas parameters entering the Platen

section

SECOND CONTROLLER

Second Controller acts on the load dependent Separator Outlet Temperature

adjusted by Platen spray differential temperature

This controller adjust the feed water in response to firing disturbances toachieve the separator O/L Temperature

THE RESULTING DEMAND FROM THE COMBINED FEEDFORWARD AND FEEDBACK

DEMANDSIGNAL DETERMINED THE SETPOINT TO THE FEED WATER MASTER CONTROL

SETPOINT

( )


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BLR PATH ( WHEN WET MODE)

Separator - Backpass Wall & Extended Wall - SH Division - Platen SH - Final SH -HP By-pass - Cold R/H Line - Primary R/H (Lower Temp R/H) - Final R/H - LP By-pass - Condenser

BLR Path (When Dry Mode)

Primary Eco - Secondary Eco - Ring HDR - Spiral W/W - W/W Intermediate HDR -Vertical W/W - Separator - Backpass Wall & Extended Wall - SH Division - PlatenSH - Final SH - HP TBN - Cold R/H Line - Primary R/H (Lower Temp R/H)- Final R/H- IP and LP TBN - Condenser

WATER & STEAM PATH


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406 451 440 486 480 540

DSH1 DSH2

15% 3%

PLATEN SH FINAL SHDIV SH


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BOILER LOAD CONDITION


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Constant Pressure Control

Above 90% TMCR The MS Pressure remains constant at rated pressure

The Load is controlled by throttling the steam flow

Below 30% TMCR the MS Pressure remains constant at minimum

Pressure

Sliding Pressure Control

Boiler Operate at Sliding pressure between 30% and 90% TMCR

The Steam Pressure And Flow rate is controlled by the load directly

CONSTANT PRESSURE VS SLIDING PRESSURE


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Valve throttling losses occur because the boiler operates at constant pressure while theturbine doesn't.

The most obvious way to avoid throttling losses therefore is to stop operating the boiler atconstant pressure!

Instead, try to match the stop valve pressure to that existing inside the turbine at any givenload.

Since the turbine internal pressure varies linearly with load, this means that the boilerpressure must vary with load similarly.

This is called .sliding pressure operation..

If the boiler pressure is matched to the pressure inside the turbine, then there are no valvethrottling losses to worry about!

While sliding pressure is beneficial for the turbine, it can cause difficulties for the boiler.

ADVERSE AFFECT

As the pressure falls, the boiling temperature (boiling point) changes. The boiler is dividedinto zones in which the fluid is expected to be entirely water, mixed steam / water or drysteam. A change in the boiling point can change the conditions in each zone.

The heat transfer coefficient in each zone depends upon the pressure. As the pressurefalls, the heat transfer coefficient reduces. This means that the steam may not reach thecorrect temperature. Also, if heat is not carried away by the steam, the boiler tubes will runhotter and may suffer damage.

CHALLANGES


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The heat transfer coefficient also depends upon the velocity of the steam in the boilertubes.

Any change in pressure causes a change in steam density and so alters the steamvelocities and heat transfer rate in each zone.

Pressure and temperature cause the boiler tubes to expand. If conditions change, thetubes will move. The tube supports must be capable of accommodating this movement.

The expansion movements must not lead to adverse stresses.

The ability to use sliding pressure operation is determined by the boiler

Boilers can be designed to accommodate sliding pressure.

When it is used, coal fired boilers in the 500 to 1000 MW class normally restrict slidingpressure to a limited load range, typically 70% to 100% load, to minimize the designchallenge. Below this range, the boiler is operated at a fixed pressure.

This achieves an acceptable result because large units are normally operated at high loadfor economic reasons.

In contrast, when sliding pressure is used in combined cycle plant, the steam pressure isvaried over a wider load range, typically 50% to 100% load or more


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ADVANTAGES


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Temperature changes occur in the boiler and in the turbine during load changes.These can cause thermal stresses in thick walled components.

These are especially high in the turbine during constant-pressure operation. Theytherefore limit the maximum load transient for the unit.

By contrast, in sliding pressure operation, the temperature changes are in theevaporator section. However, the resulting thermal stresses are not limiting in theOnce through boiler due to its thermo elastic design.

I n f ixed pressure operation , temperature change in the turbine when load

changes, while in sliding-pressure operation ,they change in the boil er


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The enthalpy increase in the boiler for preheating, evaporation and superheating

changes with pressure.

However, pressure is proportional to output in sliding pressure operation

In a uniformly heated tube, the transitions from preheat to evaporation and from

evaporation to superheat shift automatically with load such that the main steam

temperature always remains constant.

Sliding Pressure


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At loads over 25% of rated load, the water fed by a feed-water pump flows through

the high pressure feed-water heater, economizer ,furnace water wall, steam-water

separator, rear-wall tubes at the ceiling, and super heaters, The super heaters steam

produced is supplied to the turbine.

At rated and relatively high loads the boiler is operated as a purely once through

type. At partial loads, however, the boiler is operated by sliding the pressure as a

function of load.

0

5

10

15

20

25

0 25 50 75 100

Turbine load (%)

TurbineinletpressureMpa 24.1 Mpa

9.0 Mpa

g


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+1

0

-1

-2

-3

-4

20 40 60 80 100

EfficiencyCha

nge%

Boiler Load %

Variable Pressure

CONSTANT PRESSURE Vs VARIABLE PRESSURE BOILER CHARACTERSTIC

Benefits Of Sliding Pressure Operation ( S P O)


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Benefits Of Sliding Pressure Operation ( S.P.O)

Able to maintain constant first stage turbine temperature

Reducing the thermal stresses on the component : Low Maintenance & HigherAvailability

No additional pressure loss between boiler and turbine.

low Boiler Pr. at low loads.

WHY NOT S.P.O. IN NATURAL/CONTROL CIRCULATION BOILERS

Circulation Problem: instabilities in circulation system due to steam formation indown comers.

Drum Level Control: water surface in drum disturbed.

Drum : (most critical thick walled component) under highest thermal stresses


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The Basis of Boiler Start-up Mode

Mode Basis Restart Hot Warm Cold

Stopped time 2Hr Within 6~12Hr 56Hr Within 96Hr Above

SH Outlet Temp 465 above 300 above 100 above 100 belowSeparator Tank pr 120200/ 30120/ 30/ below 0/

Starting Time

Startup Mode Light off TBNRolling(minutes) Light off Full Load(minutes)

Cold 120 420 Except Rotor and Chest Warming Time

Warm 90 180 "

Hot - -

Restart 30 90

STARTING TIME

PURGE CONDITIONS


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PURGE CONDITIONS

No Boiler Trip Condition Exists

All System Power Supply Available

Unit Air Flow > 30 % BMCR

Nozzle Tilt Horizontal and Air Flow < 40 %

Both PA Fans Off

The Following Condition Exist At Oil Firing System

The HOTV / LOTV Should Be Closed

All Oil Nozzle Valve Closed

The Following Condition Exists at Coal Firing System

All Pulverisers are Off

All Feeders are Off

All Hot Air Gates Of Pulverisers are closed

All Flame Scanner on all elevation shows no Flame

Aux Air Damper At All Elevation should be modulating

After Purging B oi ler Light Up act iv i tes are same as in 500 MW plant

MFT CONDITIONS Both ID Fans Off


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Both FD Fans Off

Unit Air Flow < 30 % TMCR

All Feed Water Pumps Are Off For More Than 40 Sec

2 / 3 Pressure Transmitter indicate the furnace pressure High / Low for more than 8 sec ( 150

mmwc / -180 mmwc))

2 / 3 Pressure Transmitter indicate the furnace pressure High High / Low - Low ( 250 mmwc

/ - 250 mmwc)

Loss Of Re-heater Protection

EPB Pressed

All SAPH Off

Economizer Inlet Flow Low For More Than 10 Sec (223 T/Hr)

Furnace Vertical Wall Temperature High For more than 3 Sec (479 C)

SH Pressure High On Both Side (314 KSc)

SH Temperature High For More Than 20 Sec ( 590 C)

RH O/L Temperature High For More Than 20 Sec ( 590 C)

Separator Level Low-Low During Wet Mode ( 1.1 M)

Separator Level High-High During Wet Mode ( 17.7 M)

MFT Relay Tripped


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y pp

Loss Of Fuel Trip : It Arms when any oil burner proven.

it occurs when all of the following satisfied

All Feeders Are Off

HOTV Not Open or all HONV Closed

LOTV Not Open or all LONV Closed

Unit Flame Failure Trip : It Arms when any Feeder Proves

it occurs whenall 11 scanner elevation indicates flame failure as listed below ( Example is

for only elevation A) Feeder A & Feeder B is Off with in 2 Sec Time Delay

following condition satisfied

Any oil valve not closed on AB Elevation

3 /4 valves not proven on AB Elevation

Less Than 2 / 4 Scanner Shows Flame

Both Of The Following Condition Satisfied

Less Than 2 / 4 Scanner Flame Shows Flame

2 / 4 Oil Valves not open at AB Elevation


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SYSTEM / EQUIPMENT REQUIRED FOR BOILER LIGHT UP


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FURNACE READINESS

PRESSURE PARTS

SCANNER AIR FAN

BOTTOM ASH HOPPER READINESS

FUEL FIRING SYSTEM

START UP SYSTEM

SEC AIR PATH READINESS

FD FAN

SAPH

WIND BOX / SADC

FLUE GAS SYSTEM

ESP PASS A , B

ID FAN

SYSTEM / EQUIPMENT REQUIRED FOR BOILER LIGHT UP


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CONDENSATE SYSTEM

CONDENSER

CEP

CPU

FEED WATER SYSTEM

D/A

MDBFP # A

VACCUME SYSTEM

SEAL STEAM SYSTEM

TURBINE ON BARRING


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Evaporatorheat absorption


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Reduced number of evaporator wall tubes.

Ensures minimum water wall flow.

SPIRAL WALL ARRAMGEMENT AT BURNER BLOCK AREA :


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Support System for Evaporator Wall


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Spiral wall Horizontal and vertical buck stay with tension strip

Vertical wall Horizontal buck stay


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Documents

NTPC Sippat 3X660 MW.pdf