Transcript Document

LOW-COST TECHNOLOGICAL METHODS
TO SIGNIFICANTLY REDUCE NOx
FOR COAL-FIRED BOILERS
Felix Serant, Evgeny Russkikh SibCOTES
Anatoly Smyshlyaev - EC ZIOMAR
POWER-GEN EUROPE
June 2007
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ENERGY OF HEAT • ENERGY OF LIFE • ENERGY OF SOLUTIONS
CONTENTS
Problem of nitrogen oxides formation and the concept
of horizontally-and-vertically staged combustion
Results of the application of horizontally-and-vertically
staged combustion systems
Results of the application of horizontally-and-vertically
staged combustion systems with OFA (with coal and
gas reduction stages)
Main conclusions
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ENERGY OF HEAT • ENERGY OF LIFE • ENERGY OF SOLUTIONS
NITROGEN OXIDES FORMATION
NOx concentration, mg/Nm3
Capital costs:
90-140 $/kW
Capital costs:
10-30 $/kW
up to
Capital costs:
4-10 $/kW
FURNACE
TECHNOLOGIES
3
SNCR
SCR
Temperature range for the
application of different
methods
ENERGY OF HEAT • ENERGY OF LIFE • ENERGY OF SOLUTIONS
CONCEPT FOR NOx ABATEMENT
Lower percentage of
primary air
Active recirculation of
high-temperature furnace
gases
Longer resident time
within the reducing zone
for coal particles
NOх emission reduction
Intensive mixing of
burning pulverized coal
with secondary air
Lower temperature level
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ENERGY OF HEAT • ENERGY OF LIFE • ENERGY OF SOLUTIONS
TWO-STAGE COMBUSTION SYSTEM AT TOM-USINSKAYA
POWER PLANT, RUSSIA
Sec.conv.s/h
Boiler front
Sec.pl.s/h
Trans.zone
ECO
Tubular a/h-3
Tubular a/h-2
Tubular a/h-3
MODEL RESEARCH
1 - PC burners
2 – Oil burners
3 – Secondary air ports
4 – OFA ports
Symbol
Bituminous coal
Wr, %
11.5
Ar, %
21
Nr, %
2.1
Sr, %
0.3
Q, kJ/kg
20072
Vdaf, %
40.0
RESULTS RECEIVED
AT TOM-USINSKAYA POWER PLANT, RUSSIA
Excess air:
On burners b = 0.74-0.80
Downstream superheater s/h
= 1.25
Unburned carbon: 0.4-0.7%
Content of СО ≤ 30-50
mg/Nm3
Stable output of liquid slag
NОx,
mg/Nm3
650
700
600
500
400
300
200
100
0
380
330
Before reconstruction
After reconstruction
MODEL RESEARCH
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ENERGY OF HEAT • ENERGY OF LIFE • ENERGY OF SOLUTIONS
Boiler front
Boiler front
Boiler front
TWO-STAGE COMBUSTION SYSTEM AT POWER PLANT
EKIBASTUZSKAYA GRES-2, KAZAKHSTAN (Unit-2)
Symbol
Bituminous coal
Wr, %
7
800
Ar, %
40-49
700
Nr, %
1.5
Sr, %
0.4-0.7
Q, kJ/kg
18000-23900
Vdaf, %
27.0
mg/Nm3 NOx = 500-650 mg/Nm3 (O2=6%).
600
MODEL RESEARCH
500
400
0,5
7
0,6
0,7
0,8
0,9
1 D/D0
ENERGY OF HEAT • ENERGY OF LIFE • ENERGY OF SOLUTIONS
TWO-STAGE COMBUSTION SYSTEM AT POWER PLANT
EKIBASTUZSKAYA GRES-2, KAZAKHSTAN
ECO
Zone for bank
repl.in backpass
Content of NOx ≤ 650mg/Nm3
(planned value)
ECO
Sec.conv.s/h-1
Sec.conv.s/h-1
Sec.conv.s/h-2
Conv.s/h
Sec.conv.s/h-2
Conv.s/h
Header for ammonia
water input
Header for ammonia
water input
Platen s/h-2
Platen s/h-2
Platen s/h-1
Platen s/h-1
Expansion joint
Expansion joint
Symbol
MODEL RESEARCH
Rail road
8
Motor car road
Bituminous coal
Wr, %
7
Ar, %
40-49
Nr, %
1.5
Sr, %
0.4-0.7
Q, kJ/kg
18000-23900
Vdaf, %
27.0
ENERGY OF HEAT • ENERGY OF LIFE • ENERGY OF SOLUTIONS
Conv.s/h-1
Boiler front
Boiler front
THREE-STAGE COMBUSTION ON BOILER OP-210
AT SCAWINA POWER PLANT, POLAND
Platen s/h
ECO-2
2-nd zone
(reduction)
ECO-1
Boiler front
Boiler front
3-rd zone
(reburning)
Conv.
s/h-2,3
1-st zone
(burning)
Tubular a/h
Symbol
Bituminous coal
Wr, %
10.2-14.0
Ar, %
16.9-27.7
Nr, %
1.0
Sr, %
0.7
Q, kJ/kg
18000-23900
Vdaf, %
42.0
Tubular a/h
Tubular a/h
MODEL RESEARCH
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ENERGY OF HEAT • ENERGY OF LIFE • ENERGY OF SOLUTIONS
COAL HANDLING SYSTEM AND HIGH-DENSITY
PRESSURE FEED
Flue gases for drying from ID fan for
recirculation gases
MODEL RESEARCH
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Hot air after tubular air
pre-heater
1. Raw coal bunker (2 pcs.)
2. Raw coal feeder (2 pcs.)
3. Mill MR-19 (2 pcs.)
4. Separator (2 pcs.)
5. Cyclone (2 pcs.)
6. Pulverizing fan (2 pcs.)
7. PC bin (1 pcs.)
8. PC feeder (10 pcs.)
9. PC pipeline (8 pcs.)
10. PC pipeline (4 pcs.)
11. Main burners, 1-st tier (4
pcs.)
12. Main burners, 2-nd tier, (4
pcs.)
13. Discharge burners,
reducing stage, (4 pcs.)
14. OFA ports (4 pcs.)
15. Hot air to main burners
16. Hot air to OFA ports
17. Turbo-air-blower
18. Drying agent
recirculation line
19. Recirculation gases to
reducing stage burners
20. Input of discharge drying
agent to reducing stage
burners
ENERGY OF HEAT • ENERGY OF LIFE • ENERGY OF SOLUTIONS
RESULTS RECEIVED ON BOILER OP-210 WITH REBURNING
Excess air
downstream superheater
s/h = 1.16-1.25
NОx,
mg/Nm3
Unburned carbon: 1.0%
650
700
700
600
500
330
400
Content of CO = 20-50
mg/Nm3
300
200
100
Required values for NOx
emissions are provided within
the entire operation range:
0.7-1.0 Drated
11
0
Before reconstruction
After reconstruction
The cost of the reconstruction was
about $ 10 per 1 kW of the rated
power unit capacity
ENERGY OF HEAT • ENERGY OF LIFE • ENERGY OF SOLUTIONS
RESULTS OF STAGE COMBUSTION SYSTEMS APPLICATION
1200
NОx,
mg/nm3
1200
Bituminous coal
Lignite
920
900
1000
700
800
650
650
600
600
550
600
380
450
420
400
330
350
300
400
200
0
Ekibastuzskaya
Tom-Usinskaya
MODEL RESEARCH
GRES-2
(Kazakhstan)
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GRES (Russia)
Novosibirsk CHP- Belovskaya GRES
5 (Russia)
(Russia)
Tuncbilek Power
Plant (Turkey)
Scawina Power
Plant (Poland)
Gacko Power Plant
(Bosnia)
Novoirkutskaya
CHP (Russia)
Neivelly Power
Plant (India)
ENERGY OF HEAT • ENERGY OF LIFE • ENERGY OF SOLUTIONS
THREE-STAGE COMBUSTION WITH GAS REBURNING ON BOILER
TPE-214 AT NOVOSIBIRSKAYA CHP-5 POWER PLANT, RUSSIA
56200
1-tier burners
Gas-fired burners
OFA level
Air
Bituminous coal
Wr, %
12
Ar, %
13
%
2
Sr, %
0.4
Q, kJ/kg
22880
4
28400
3
6
23830
Nr,
32670
18300
0,1Q
2
1
zone I
Symbol
zone II
5
Air
zone III

9
0,9Q
14700
Vdaf,
%
40.0
1 – 1-tier
burners;
2 – 2-tier burners; 3 – gas reburn burners; 4 – OFA
MODEL
RESEARCH
ports; 5 - control gate-valves on secondary air input ; 6 – Venturi
tubes; 7 – natural gas flow-meter; 8 – Venturi tube at recycle gas
feeding to ports of reducing stage; 9 – secondary air ports.
Natural Gas
7
8
IDF-gas
recirculation
Flue gases after ID Fans
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ENERGY OF HEAT • ENERGY OF LIFE • ENERGY OF SOLUTIONS
RESULTS RECEIVED ON BOILER TPE-214 WITH REBURNING
q4 ,
%
2
2
1
1
0
h
gr
boiler
520
560
600
640
680
94
1
%
93
2
92
91
NОx,
520
560
500
3
mg/nm
600
640
680
1
2
400
300
520
MODEL RESEARCH
560
600
640
1 – two-stage combustion; 2 – three-stage combustion
14
680
Дпр, ,t/h
т/ч
Dboiler
ENERGY OF HEAT • ENERGY OF LIFE • ENERGY OF SOLUTIONS
CONCLUSIONS
Low-cost technological methods - first, and most efficient way to reduce NOx
Developed concept of horizontally-and-vertically staged combustion was applied on
many boilers firing a wide range of fuels, and it ensures 30-50% NOx reduction
Technology of horizontally-and-vertically staged combustion is a low-cost measure,
at the same time, it is highly efficient
Vast experience accumulated by Russian power engineers in design and application of
furnace and burner arrangements and fuel handling systems can be used worldwide
to ensure efficient NOx abatement
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THANK YOU FOR YOUR
ATTENTION!
www.cotes.ru
e-mail: [email protected]
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ENERGY OF HEAT • ENERGY OF LIFE • ENERGY OF SOLUTIONS