Cfb Presn-ntpc11.07.06
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Presentation on CFBC Boilers
Welcome to Presentation on
CFBC Boilers
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers CFBC Development Journey •
Test Facility installed – 1991
•
Collaboration with LLB ( LEE ) – 1993
•
Technology transfer/Training of Engineers - 1996
•
First non –reheat boiler (175 t/h ) installed at BILT , Bhigwan - 1998
•
First Utility reheat boiler ( 2x125 MW ) installed at SLPP , Mangrol - 1999
•
Testing of Lignite – 2001
•
125 MW order received from RVUNL, Giral – 2003
•
75 MW order received from GEB, Kutch – 2004
•
2 x 135 t/h order received from M/s Gujarat Ambuja cement - 2004
•
2 x 250 MW order received from Neyveli Lignite Corporation – 2005
•
125 MW repeat order received from RVUNL, Giral – 2005
•
2 x 125 MW order received from NLC – Barsingsar firing Rajasthan Lignite– Oct 2005
•
2 x 125 MW repeat order received from SLPP – March 2006 Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers Basic Flow Diagram of CFBC Boiler
SECONDARY AIR
ID Fan
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers
Advantages of CFBC
Simplified Fuel Preparation and feeding (No Pulveriser) In-Situ SOx and NOx control Oil support for load below 30% and start up only Slag-Free Combustion. Dry ash powder only FSSS avoided. Burner Management for Start-Up Burner only Lower Temperature / Less Intense (no flame) Combustor Environment Suitable for using wide range of fuels in the same boiler Suitable for fuels which are difficult to burn High Carbon Burn-out (Very low carbon in ash)
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers
Why Fluid Bed Combustion ?
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers
SOx Control • Sulphur in fuel captured in combustor by addition of limestone • Ca/S Molar Ratio varies between 1.5 to 2.5 depending on the Limestone Quality • Expensive (FGD) add-on equipment avoided. Reliability improved
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers
SO2 Control Reactions • Straightforward method - Limestone addition along with fuel into combustor • Reactions S + O2
SO2
CaCO3
CaO + CO2
CaO + SO2 + 1/2 O2
(Calcination) CaSO4
(Sulphation)
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers
Limestone Requirement
Limestone Requirement
Temperature Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers
Formation of NOx and Control • NOx formation Thermal NOx - Nitrogen in Air Fuel NOx - Nitrogen in Fuel • Thermal NOx depends on Combustion temperature In FBC boilers, the Combustion temperature is around 850°C, hence Thermal NOx is negligible • Fuel NOx depends on excess air levels & Staging In addition to low excess air levels, the combustion air is staged. Hence Fuel NOx is also low Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers Advantages of FBHE
Spiess Valve
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers
Distinct Advantages of FBHE ❁
Elimination of heat transfer bundle / panel in combustor
❁
Very Low carbon in ash and Limestone consumption even at part load due to Optimum combustor temperature (about 850 Deg C )
❁
Better fuel flexibility due to provision for adjusting heat absorption
❁
Higher efficiency and reduced NOx emission even at part load due to constant excess air
❁
Unique RH temperature control option
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Comb. Temp.
Presentation on CFBC Boilers
Without FBHE
With FBHE
FBHE
Heat duty
Combustor Conv. Pass
Fuel Quality / Load
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers
SINARMAS 175 t/h CFBC Boiler • Fuel
Coal (Imported+Indian)
• Commissioned
March 1998
• Total hours logged
65,000
• Minimum load achieved (without Oil support)
20 % MCR
• Controllability Range (achieved) 30 to 100% • Generally in Continuous operation between planned annual stoppages Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers Arrangement (Elevation) of Bilt Graphics CFBC Boiler
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers
SLPP 2 x 125 MW CFBC BOILER Location Fuel
: :
Mangrol , Surat Dt , Gujarat Lignite ( 50 % M & 2.5 %S) HHV - 2500 to 5500
Total hours logged
:
65,000
SH Steam
:
390 T/H, 132 ATA, 540 0C
RH Steam
:
350 T/H, 32.5 ATA, 540 0C
Boiler Parameters
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers Arrangement (Plan) of SLPP CFBC Boiler
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers Arrangement (Elevation) of SLPP CFBC Boiler
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers View of 2 x 125 MWe SLPP
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers
SLPP -
Lignites Used
Fuel Fixed Carbon Volatile Matter Moisture Ash Sulphur* HHV
% % % % %
Design
Actual
14 - 40 25 - 44 10 - 50 7 - 48 0.36 – 2.5
18 - 33 21 - 26 41 - 48 4-8 0.3 - 2
kcal/kg 2500 -5500 2300 - 4775
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers
SLPP Performance Fuel Carbon Hydrogen Sulphur Nitrogen Oxygen (by diff.) Moisture Ash HHV
% % % % % % %
Design
Actual
43.30 3.14 1.20 (2.5) 0.81 8.53 24.00 19.02
30.75 3.48 1.18 0.43 7.61 42.44 14.10
kcal/kg 4250
Chlorine content in Lignite
Not identified
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
3090 0.3-0.4% FBC & HRSG
Presentation on CFBC Boilers
RVUNL – Giral 125 MW
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers
Comparison of SLPP – Giral (Boiler parameters ) Parameter
Unit
SLPP
Giral
Unit Rating MW Type of Circulation
125 Natural
125 Natural
SH/RH Flow SH/RH Pres. SH/RH Tem. FW Tem.
390 / 350 132 / 30.5 540 / 540 235
405 / 336 132 / 34 540 / 540 237
t/h kg/cm2 Deg C Deg C
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers Lignite Analysis - Comparison SLPP Proximate Analysis (% by weight) Moisture Ash Volatile Matter Fixed Carbon (by diff.) HHV, kcal/kg Ultimate Analysis (% by weight) Carbon Hydrogen Sulphur Oxygen Nitrogen Moisture Ash
24 19.02 32.52 24.46 4240
Giral 10-50 7-48 25-44 14-40 2500-5500
43.3 3.14 1.2 (max 2.5) 8.55 0.81 24.0 19.02
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
40 15 20 25 3000 30.09 2.24 6.00 6.27 0.4 40.0 15.0 FBC & HRSG
Presentation on CFBC Boilers Limestone Analysis - Comparison
Analysis (% by weight) CaCO3 MgCO3 SiO2 Moisture Others
SLPP
Giral
85.23 1.18 8.65 2.05 2.89
96.8 1.2 1.15 0.28 0.57
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers
Giral – Design Evolution
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers
Giral CFBC Boiler Design - Evolution • About 50 feedbacks from the operational experience from SLPP and BILT Graphics • Learnings from 158 SARs from SLPP and Bilt Graphics incorporated • Discussions with Manufacturing and OP&C groups • Discussions with Erection Group PSWR
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers 250 MW CFBC Flow Schematic
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers COAL BUNKERS
CONVECTIVE PASS CYCLONES
SPECIAL COMBUSTOR
SEC. APH ( REGEN ) FBHE
250 MW CFBC Boiler Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers Gardanne 250 MW CFBC Plant
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers
General Arrangement of 250 MW CFBC boiler
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
on CFBC Boilers BHEL Presentation - LEE Foster wheeler
PYROPOWER (IJT)
LLB (BHEL)
870C
850C
TO BACKPASS
Fuel - Coal
TO BACKPASS
800-1000C
650-850C
CYCLONE
CYCLONE
COMBUSTORWING WALL
CL- 2-3% CL- < 1.5%
SH
SOx - 150-250
CFB COMBUSTOR
SOx - 100
CFB COMBUSTOR
SEAL POT
SPIESS VALVE
SECONDARY AIR
NOx - 50
NOx - 50-200 SECONDARY AIR
LOOP SEAL
700-900C
850C
FUEL
FUEL
FBHE
BHELAFBC
PRIMARY AIR
PRIMARY AIR
CL < 3.5%
Krupp Industrie DBW (KRUPP)
TBW
FBC
FBC
B&W (TBW )
SOx – 150-300
TO BACKPASS
NOx – 200-300 300-400C
IN FURNACE U-BEAMS
U-BEAMSEP.
SUPERHEATERS
TO BACKPASS CYCLONE
300-400C
ECO
DIVISION WALL
650-790C BED MATERIAL BIN
FlyAsh reinjection 150C
CFB COMBUSTOR
SH1
CL - 3-4%
SH2
SOx - 150-300
SECONDARY AIR
CL - 3-4%
SECONDARY AIR
NOx - 150-300
FUEL
SIPHON SEAL
700-900C
FUEL
SOx - 150-300
700-870C PRIMARY AIR
NOx - 150-300 PRIMARY AIR
FBC SOx, Limited NOx – in TIRUCHIRAPALLI ppm Bharat Heavy Electricals
FBC
FBC FBC & HRSG
Presentation on CFBC Boilers
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Welcome to Presentation on
CFBC Boilers
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers CFBC Development Journey •
Test Facility installed – 1991
•
Collaboration with LLB ( LEE ) – 1993
•
Technology transfer/Training of Engineers - 1996
•
First non –reheat boiler (175 t/h ) installed at BILT , Bhigwan - 1998
•
First Utility reheat boiler ( 2x125 MW ) installed at SLPP , Mangrol - 1999
•
Testing of Lignite – 2001
•
125 MW order received from RVUNL, Giral – 2003
•
75 MW order received from GEB, Kutch – 2004
•
2 x 135 t/h order received from M/s Gujarat Ambuja cement - 2004
•
2 x 250 MW order received from Neyveli Lignite Corporation – 2005
•
125 MW repeat order received from RVUNL, Giral – 2005
•
2 x 125 MW order received from NLC – Barsingsar firing Rajasthan Lignite– Oct 2005
•
2 x 125 MW repeat order received from SLPP – March 2006 Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers Basic Flow Diagram of CFBC Boiler
SECONDARY AIR
ID Fan
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers
Advantages of CFBC
Simplified Fuel Preparation and feeding (No Pulveriser) In-Situ SOx and NOx control Oil support for load below 30% and start up only Slag-Free Combustion. Dry ash powder only FSSS avoided. Burner Management for Start-Up Burner only Lower Temperature / Less Intense (no flame) Combustor Environment Suitable for using wide range of fuels in the same boiler Suitable for fuels which are difficult to burn High Carbon Burn-out (Very low carbon in ash)
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers
Why Fluid Bed Combustion ?
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers
SOx Control • Sulphur in fuel captured in combustor by addition of limestone • Ca/S Molar Ratio varies between 1.5 to 2.5 depending on the Limestone Quality • Expensive (FGD) add-on equipment avoided. Reliability improved
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers
SO2 Control Reactions • Straightforward method - Limestone addition along with fuel into combustor • Reactions S + O2
SO2
CaCO3
CaO + CO2
CaO + SO2 + 1/2 O2
(Calcination) CaSO4
(Sulphation)
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers
Limestone Requirement
Limestone Requirement
Temperature Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers
Formation of NOx and Control • NOx formation Thermal NOx - Nitrogen in Air Fuel NOx - Nitrogen in Fuel • Thermal NOx depends on Combustion temperature In FBC boilers, the Combustion temperature is around 850°C, hence Thermal NOx is negligible • Fuel NOx depends on excess air levels & Staging In addition to low excess air levels, the combustion air is staged. Hence Fuel NOx is also low Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers Advantages of FBHE
Spiess Valve
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers
Distinct Advantages of FBHE ❁
Elimination of heat transfer bundle / panel in combustor
❁
Very Low carbon in ash and Limestone consumption even at part load due to Optimum combustor temperature (about 850 Deg C )
❁
Better fuel flexibility due to provision for adjusting heat absorption
❁
Higher efficiency and reduced NOx emission even at part load due to constant excess air
❁
Unique RH temperature control option
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Comb. Temp.
Presentation on CFBC Boilers
Without FBHE
With FBHE
FBHE
Heat duty
Combustor Conv. Pass
Fuel Quality / Load
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers
SINARMAS 175 t/h CFBC Boiler • Fuel
Coal (Imported+Indian)
• Commissioned
March 1998
• Total hours logged
65,000
• Minimum load achieved (without Oil support)
20 % MCR
• Controllability Range (achieved) 30 to 100% • Generally in Continuous operation between planned annual stoppages Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers Arrangement (Elevation) of Bilt Graphics CFBC Boiler
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers
SLPP 2 x 125 MW CFBC BOILER Location Fuel
: :
Mangrol , Surat Dt , Gujarat Lignite ( 50 % M & 2.5 %S) HHV - 2500 to 5500
Total hours logged
:
65,000
SH Steam
:
390 T/H, 132 ATA, 540 0C
RH Steam
:
350 T/H, 32.5 ATA, 540 0C
Boiler Parameters
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers Arrangement (Plan) of SLPP CFBC Boiler
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers Arrangement (Elevation) of SLPP CFBC Boiler
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers View of 2 x 125 MWe SLPP
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers
SLPP -
Lignites Used
Fuel Fixed Carbon Volatile Matter Moisture Ash Sulphur* HHV
% % % % %
Design
Actual
14 - 40 25 - 44 10 - 50 7 - 48 0.36 – 2.5
18 - 33 21 - 26 41 - 48 4-8 0.3 - 2
kcal/kg 2500 -5500 2300 - 4775
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers
SLPP Performance Fuel Carbon Hydrogen Sulphur Nitrogen Oxygen (by diff.) Moisture Ash HHV
% % % % % % %
Design
Actual
43.30 3.14 1.20 (2.5) 0.81 8.53 24.00 19.02
30.75 3.48 1.18 0.43 7.61 42.44 14.10
kcal/kg 4250
Chlorine content in Lignite
Not identified
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
3090 0.3-0.4% FBC & HRSG
Presentation on CFBC Boilers
RVUNL – Giral 125 MW
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers
Comparison of SLPP – Giral (Boiler parameters ) Parameter
Unit
SLPP
Giral
Unit Rating MW Type of Circulation
125 Natural
125 Natural
SH/RH Flow SH/RH Pres. SH/RH Tem. FW Tem.
390 / 350 132 / 30.5 540 / 540 235
405 / 336 132 / 34 540 / 540 237
t/h kg/cm2 Deg C Deg C
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers Lignite Analysis - Comparison SLPP Proximate Analysis (% by weight) Moisture Ash Volatile Matter Fixed Carbon (by diff.) HHV, kcal/kg Ultimate Analysis (% by weight) Carbon Hydrogen Sulphur Oxygen Nitrogen Moisture Ash
24 19.02 32.52 24.46 4240
Giral 10-50 7-48 25-44 14-40 2500-5500
43.3 3.14 1.2 (max 2.5) 8.55 0.81 24.0 19.02
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
40 15 20 25 3000 30.09 2.24 6.00 6.27 0.4 40.0 15.0 FBC & HRSG
Presentation on CFBC Boilers Limestone Analysis - Comparison
Analysis (% by weight) CaCO3 MgCO3 SiO2 Moisture Others
SLPP
Giral
85.23 1.18 8.65 2.05 2.89
96.8 1.2 1.15 0.28 0.57
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers
Giral – Design Evolution
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers
Giral CFBC Boiler Design - Evolution • About 50 feedbacks from the operational experience from SLPP and BILT Graphics • Learnings from 158 SARs from SLPP and Bilt Graphics incorporated • Discussions with Manufacturing and OP&C groups • Discussions with Erection Group PSWR
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers 250 MW CFBC Flow Schematic
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers COAL BUNKERS
CONVECTIVE PASS CYCLONES
SPECIAL COMBUSTOR
SEC. APH ( REGEN ) FBHE
250 MW CFBC Boiler Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers Gardanne 250 MW CFBC Plant
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
Presentation on CFBC Boilers
General Arrangement of 250 MW CFBC boiler
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
on CFBC Boilers BHEL Presentation - LEE Foster wheeler
PYROPOWER (IJT)
LLB (BHEL)
870C
850C
TO BACKPASS
Fuel - Coal
TO BACKPASS
800-1000C
650-850C
CYCLONE
CYCLONE
COMBUSTORWING WALL
CL- 2-3% CL- < 1.5%
SH
SOx - 150-250
CFB COMBUSTOR
SOx - 100
CFB COMBUSTOR
SEAL POT
SPIESS VALVE
SECONDARY AIR
NOx - 50
NOx - 50-200 SECONDARY AIR
LOOP SEAL
700-900C
850C
FUEL
FUEL
FBHE
BHELAFBC
PRIMARY AIR
PRIMARY AIR
CL < 3.5%
Krupp Industrie DBW (KRUPP)
TBW
FBC
FBC
B&W (TBW )
SOx – 150-300
TO BACKPASS
NOx – 200-300 300-400C
IN FURNACE U-BEAMS
U-BEAMSEP.
SUPERHEATERS
TO BACKPASS CYCLONE
300-400C
ECO
DIVISION WALL
650-790C BED MATERIAL BIN
FlyAsh reinjection 150C
CFB COMBUSTOR
SH1
CL - 3-4%
SH2
SOx - 150-300
SECONDARY AIR
CL - 3-4%
SECONDARY AIR
NOx - 150-300
FUEL
SIPHON SEAL
700-900C
FUEL
SOx - 150-300
700-870C PRIMARY AIR
NOx - 150-300 PRIMARY AIR
FBC SOx, Limited NOx – in TIRUCHIRAPALLI ppm Bharat Heavy Electricals
FBC
FBC FBC & HRSG
Presentation on CFBC Boilers
Bharat Heavy Electricals Limited TIRUCHIRAPALLI
FBC & HRSG
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