ntpc sippat 3x660 mw.pdf
TRANSCRIPT
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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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40
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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