264_Qi_Yang_Zhang_FHMT_2017.pdf

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Frontiers in Heat and Mass Transfer (FHMT), 8, 3 (2017)

DOI: 10.5098/hmt.8.3

Global Digital Central

ISSN: 2151-8629

NUMERICAL ANALYSIS OF NO

X PRODUCTION UNDER THE AIR

STAGED COMBUSTION

Xiangcun Qi

, Mo Yang

, Yuwen Zhang

a School of Energy and Power Engineering, University of Shanghai for Science and Technology, Shanghai, 200093

China

b Department of Mechanical & Aerospace Engineering, University of Missouri, Columbia, MO 65211, USA ABSTRACT

The

n of thermal NO and fuel type NO emission under the air staged combustion in a tower pulverized coal fired boiler that burners are

arranged in the front and the rear wall are investigated in this paper.

Effect

s of the distribution of oxygen in the main combustion zone on NO

then analyze qualitatively. The results show that when the SOFA ratio is 34.98%, NO

x yield is

t the minimum; thermal NO is not only related to

temperature, but also by the influence of oxygen distribution

. When oxygen is more and the temperature is high, it is conducive to the formation of

thermal NO

The formation of fuel NO and the amount of oxygen and CO have a positive

relation, and more oxygen is conducive to the formation

of thermal NO

When CO is more, indicating that the reducibility is good, it will

n of fuel NO

Based on the control of

the mount of SOFA, the distribution of oxygen in the main combustion zone must be on the rational allocation

; in the case of normal combustion, the

input of air could not be too much through the first layer burners.

Keywords: Air staged combustion; Numerical simulation; Thermal NO; Fuel NO

* Corresponding author. Email: yangm

usst.edu.cn

1. INTRODUCTION

e recent years, with the development of economy, people pay

more and more attention

s to energy conservation and emission

reduction

The NO

x is one of the main air pollutants,

d reducing

x emissions has become the main research target of many scholars

worldwide

. The most common method

e air staged combustion,

fuel staged combustion, low oxygen combustion, flue gas

recirculation, the addition of reducing agent and so on (Cen et al.,

2004). Air staged combustion is the most common method to reduce

the NO

for pulverized coal fired boiler

Many scholars have done a lot of researches on air staged

combustion in pulverized coal fired boiler

(

;

(

)

d Cheng et al.,

2015

)

The influence

s of overfire air on NO

x emission

, and researches show that OFA investment made the main

combustion zone be in fuel rich combustion

s is not conducive to

the formation of NO

x, and

makes the furnace exit NO

x emissions

reduction. Li et al.

(2015

) and Zhou et al.

(2011

) studied a 300MW

coal

-fired boiler and a 1000 MW

tangentially

fired

pulverized

coal

boiler of low NO

x combustion retrofit, which increase

s the SOFA

system, making air depth classification, can reduce the production of

. Li et al.

(2014

) and Sun et al. (2013) focused on the tangentially

fired boiler with low nitrogen transformation and analyzed the

furnace NO

x emission characteristics. Hong et al. (2012) focused on

an o

pposed

firing

boiler

supercritical

unit and analy

zed

emission

characteristics of CO and NO

l results showed that the SOFA can

effectively reduce the NO

x yield and the higher of air damper

opening degree, the smaller NO

x yield of furnace outlet.

Influences of different SOFA ratios on NO

x emission in a tower

pulverized coal fired boiler that burners are arranged in the front and

the rear wall are investigated in this paper.

n and influence

factor of thermal NO and fuel type NO emission

s are investigated

under

optimal operating conditions

The effect of the distribution of

oxygen in the main combustion zone on NO

d. It

provides a certain reference for the engineering to reduce the NO

emission by using the air staged combustion technology.

Fig.

1 Physical model and calculation model

14.960 m

11.455 m

18.465 m

25.015 m NO

x nozzles

12.3 m

DCB

13.8 m

48.5 m

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Frontiers in Heat and Mass Transfer (FHMT), 8, 3 (2017)

DOI: 10.5098/hmt.8.3

Global Digital Central

ISSN: 2151-8629

2. MATHEMATICAL AND PHYSICAL MODE

2.1 Object of

Study

The symmetric model is

y used to reduce the computational

complexity. There are a lot of papers

(Yang et al., 2014; Shen et al.,

2016) about nonlinear problems which prove the existence of

nonlinear

a. In order to improve the

y of the

simulation, the full scale model is used to calculate.

The object of this paper is to study a B&WB

-1025/17.5

-M type

single chamber, single steam drum, front and back wall convection

combustion of pulverized coal boiler. This model of pulverized coal

boiler is shown in Figure

1. Burners are arranged in the front and the

rear wall of the boiler. The front wall is arranged with three layers of

burners (from bottom to top are B, D and C), and the rear wall is

arranged with two layers of burners (from bottom to top are A and E),

with each layer having 4 burners; the bottom 8 burners are DRB

4ZTM burners, and the other 12 are AirJetTM burners. The SOFA

nozzle

s are arranged in the most upper burner of front and back wall,

with each layer has 4 SOFA nozzles (8 only), and all SOFA nozzles

are in the same elevation.

2.2 Physical

Model and

Boundary

Condition

Three

-dimensional steady

state model is employed to simulate the

combustion and NO

x formation in pulverized coal fired boiler. Grid is

structured hexahedral mesh, and specific division as shown in Figure

2. After grid size independent test, the total number of grids is about

2.26 million.

The air distribution of the two burners used in the boiler is

shown in Figure 3, and pulverized coal is

d into the furnace

through the primary air. The analysis of the boiler operating

conditions is 270MW, and the excess air coefficient is 1.20. The

pulverized coal is put into the furnace through the first layer and the

second layer burners. Third burners only input secondary air. SOFA

is input by SOFA nozzles. This boiler coal is bituminous coal, which

the element analysis and industrial analysis are shown in

Table 1. All

the nozzles of the burner are set to

e the velocity inlet, the outlet of

the furnace is set as the pressure outlet, and the wall surface of the

furnace is provided with no slip boundary conditions, and the

temperature of the furnace wall is 700 K (according to the

experimental results).

Table 1

The industrial analysis and element analysis Industrial analysis /% Var FCar Aar Mar

Qnet(kJ/kg)

26.93 45.39 16.30 11.38 23160 Element analysis /% Cdaf Hdaf Odaf Ndaf Sdaf

81.33 5.00 11.42 1.30 0.95

2.3

Mathematical

Model

2.3.1 Flow and

Combustion

Model

According to the theory of combustion of pulverized coal in the

furnace, gas turbulent flow model is the realization k

ε (2 eqn) model.

Turbulent dispersion of coal particles uses discrete random walk

model, and devolatilization model is

e single

-rate. The char

combustion model is kinetics/diffusion

-limited, and the radiation heat

transfer is simulated by the P1 radiation model; turbulent flow

diffusion flame uses the Non

-Premixed combustion model

(Smoot

and Pratt, 1979

)

The pressure based solver is used to simulate the cold and hot

state of the boiler, and the patch button is used to initialize the

temperature field (2000K) for ignition. Firstly, the combustion in the

furnace is simulated, and the generation of NO

x is not considered.

Finally, the post processing method is used to calculate the NO

generation.

2.3.2 NO

Formation

Model

In the thermal power plant, the NO

x of the pulverized coal boiler is

mainly NO and NO

2. The content of NO is 95% (volume

concentration) of total NO

x. So the calculation mainly consider the

generation of NO, which can be converted into NO

x through

conversion relations. The generation of NO

x is based on the PDF

transport equation model. NO

x is divided into thermal NO

x, fuel NO

and prompt NO

. And prompt NO

x is less in pulverized coal boiler,

so it is neglected

Fig.

2 Grid division in the furnace

Fig.

3 Air distribution of burner

(b) AirJetTM

Center air

Pri

mary air

Internal secondary

air

External secondary air

(a) DRB

-4ZTM

Primary

air

Transition air

Internal secondary air

External secondary

air

Page 3 of 8

Frontiers in Heat and Mass Transfer (FHMT), 8, 3 (2017)

DOI: 10.5098/hmt.8.3

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ISSN: 2151-8629

Thermal NO

x is the oxidation product of

2 in air at high

temperature. And its formation process is a no branch chain reaction,

mainly affected by temperature, with its formation mechanism

represented by Zeldovich reactio

(Hill and Smoot, 2000

). Reaction 1

is the decomposition of nitrogen, due to the decomposition of the

required activation energy is relatively large, so the reaction must be

carried out at high temperature. The speed of the whole chain

reaction is mainly determined by the slowest reaction type 1.

N O N NO 

  (1) 22

O N NO O 

  (2) 33 kk

OH N NO H 

 

(3)

The fuel NO

x reaction is relatively complex, using the De Soete

mode

(Soete, 1975)

, and its formation is divided into two parts, the

oxidation of volatile N and the oxidation of char N, as shown in

Figure

4. The intermediate product of volatile N to NO is HCN and

i. Char N is directly oxidized to NO

x. And a part of NO

x can be

reduced into N

3. RESULTS AND

3.1 Effect of SOFA on NO

The analysis of the boiler operating conditions is 270MW, and the

total air volume and total amount of coal remain unchanged.

Conditions of six different ratios of SOFA are numerically simulated

by adjusting the air ratio.

Analyze NO

x yield under different SOFA

ratios

(NO

x yield under 6% oxygen content). NO

x distribution is

shown in

Figure 5. 0 10 20 30 40 0

100

150

200

250

300 NOx /mgm-3

High /m

26.02%

30.95%

33.48%

34.98%

36.02%

38.48%

Fig.

5 The NO

x distribution of different SOFA condition

It can be seen from the figure that the air staged combustion is

beneficial to reduce the NO

x production in the main combustion zone.

Only in the vicinity of the burner NO

x production is slightly higher,

the other region is in a better reducing atmosphere, is not conducive

to the production of NO

. And the yield of NO

x and SOFA ratios

have a great relationship. It is not true that the more SOFA ratio, the

better air staged combustion, and the less NO

x emissions. This is due

to the input of SOFA through nozzles which have destroyed the

reductive environment, and supply a large amount of air for coal

combustion, and NO

x production begin to increase. If it doesn

’

reasonably control the output of this area NO

x, even if the main fuel

area NO

x production is very low, still makes the furnace outlet NO

production is very large. Considering the change of the whole furnace

production of NO

x can be seen that with SOFA from less to more, the

x production of furnace outlet decreased first and then increased.

For the boiler in 270MW load, when the SOFA ratio is 34.98%, the

yield of NO

x is minimum. So select the optimal working conditions

as the research object, through the study of the distribution of NO

analysis of the generation mechanism of NO

3.2 Distribution of

Thermal NO

Figure 6 is the distribution of temperature and thermal NO in the

longitudinal section of the furnace (z=6.9). It can be clearly seen that

the distribution of thermal NO is similar to temperature. In the high

temperature region of the furnace, it is conducive to the generation of

thermal NO. In the lower temperature zone, the thermal NO

production is also less, just according with the formation mechanism

of the thermal type NO.

And it can be seen from the figure, in addition to the high

temperature region in the main combustion zone will produce a large

amount of thermal NO, in the burnout zone because of SOFA input,

making unburned coal combustion in the region area, the temperature

increased, it is accompanied by generation of a part of thermal NO.

In order to further analyze the law of thermal NO, this paper

also takes the section average value of thermal NO generation rate,

temperature, oxygen and CO along the height of furnace, as shown in figure 7 and 8.

From the change curve of the section average of thermal NO it

can be seen that its change trend is very similar with oxygen, and

from Zeldovich mechanism, it is found that the formation of thermal NO is not only related to temperature, but also influenced by oxygen.

Char

Fig.

Formation mechanism of fuel NO

Volatile N

Char N

HCN

、NHi

Fig.

6 The distribution of temperature (K) and thermal NO

(

μL/L) in the longitudinal section of the furnace (z=6.9)

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Frontiers in Heat and Mass Transfer (FHMT), 8, 3 (2017)

DOI: 10.5098/hmt.8.3

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ISSN: 2151-8629

In the main combustion zone, the formation rate of thermal NO

has been decreased two times. Because the air staged combustion to

make this area as a whole is in negative oxygen combustion. The

oxygen content is relatively high in the vicinity of burners, and in

other areas oxygen content is very low. Therefore, the thermal NO

decreased with the decrease of the oxygen content of two times. It

can be seen that in the high temperature region, the formation of

thermal NO is also affected by oxygen. When the oxygen is sufficient,

thermal NO can be produced in a large amount; when the oxygen is

insufficient, even if the temperature is appropriate, there will not be

thermal NO formation. 0 10 20 30 40

0.0

4.0x10-8 8.0x10-8 1.2x10-7 1.6x10-7 2.0x10-7 Thermal NO Rate Temperature

High /m Thermal NO Rate /kgmolm-3s-1

1100

1200

1300

1400

1500

1600 Temperature /K

Fig.

The section average value of thermal NO rate, temperature 0 10 20 30 40 0246 O2 CO

High /m O2 /% 0369

15 CO /%

Fig.

The section average value of

2 and CO

At the height of 18.5 m, which is near the third layer burners,

the oxygen content increases, but the heat type NO generation rate of

the area is not increased from figure 7. From figure 8 it can be seen

that the amount of CO in this area is very high, and form a strong

reducing state, which makes some thermodynamic NO is reduced,

and is not conducive to the oxidation of N. Therefore, the region's

thermal NO generation rate is very small.

At about the height of 25m, which is near the SOFA nozzle,

because the cooling effect of SOFA, temperature decreased firstly,

then with the unburned pulverized coal burning in sufficient oxygen,

the temperature increased rapidly. But the change curve of the

thermal NO generation rate was obviously increased at the lowest

temperature. From figure 8 it can be seen that its change trend is very

similar with oxygen. The three reaction of Zeldovich mechanism is

used to analyze, because the temperature of the main combustion

zone is relatively high, the reaction 1 is normally carried out, and the

nitrogen is decomposed to generate a part of N atoms. But because of

the relatively high amount of CO in the main combustion zone, the

whole is in a reduced state, which is not conducive to the reaction of

2 and 3. So there is a large amount of N atoms to be remained in the

main combustion zone. Due to the addition of SOFA, the oxygen

content increased, CO decreased, and N atoms was oxidized to

generate a large amount of NO by the reaction of 2 and 3 (reaction 2

and 3 don’t need high temperature). The change trend of the thermal

NO generation rate increases with the increase of oxygen in this

region, and it seems that the relationship with temperature is not very

big. In the vicinity of the Arch Nose, the thermal NO formation rate

also had a small fluctuation. Because the bending angle makes the

temperature of the partial area is higher.

Under the condition of the boiler, the temperature in the furnace

is not very high (below 1500

C), which is not conducive to the

formation of thermal NO

x. So the thermal NO

x production in this

boiler is relatively small, only about 12% of the total NO

x yield.

3.3 Distribution of

Fuel NO

3.3.1 Distribution of Volatile NO

From the formation mechanism of fuel NO

x in figure 4, fuel NO is

divided into two parts, the oxidation of volatile N and the oxidation

of char N, as shown in

figure

4. In this paper, try to simulate the

formation of these parts separately, so as to analyze the distribution

of NO in a qualitative way. Among them, with the precipitation of

volatile, volatile

N was quickly oxidized into NO. The whole process

mainly occurs near the burners in the main combustion zone, as

shown in

Figure 9.

Fig.

9 The distribution of volatile NO

From the volatile NO distribution of the cross section

s of the

first layer and the second layer of the burner

s can be seen, these two

distribution

s are significantly different. The first layer is DRB

-4ZTM

burner

s. From inside to outside there are 4 channels, which are

respectively primary air, transition air, internal secondary air and

external secondary air. Pulverized coal with primary air enters the

furnace. Volatile evaporates in the outside of the primary air, and the

volatile N is also immediately oxidized to NO. So in the center area

volatile NO is little and in the outer region a large amount of volatile

NO will be product. The second layer is the AirJetTM burners. From

inside to outside there are 4 channels, which is respectively center air,

primary air, internal secondary air

, and external secondary air.

layer burner

(b) Cross section of the first

layer burner

(a) Longitudinal section of furnace (Z=5.4375)

Page 5 of 8

Frontiers in Heat and Mass Transfer (FHMT), 8, 3 (2017)

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Volatile evaporates in the outside of the primary air with a large

amount of volatile NO formation. So it can be seen from the figure C,

volatile NO mainly generated in the region of center air and

secondary air. Yield is less in the region of primary air.

3.3.2 Distribution of Char NO

Fig. 10 The distribution of char NO (Z=5.4375) 0 10 20 30 40

0.0

5.0x10-6

1.0x10-5 Char NO Rate DPM Burnout

High /m Char NO Rate /kgmolm-3s-1

0.0

2.0x10-5

4.0x10-5 DPM Burnout /kgs-1

Fig. 11 The section average value of char NO rate and char

combustion rate

Figure

s 10 and 11 show the distribution of char NO in the furnace

(Z=5.4375 m), and the section average value of char NO formation

rate and char combustion rate along the furnace height.

From the figure it can be clearly seen that a large amount of the

char NO generated in the hopper area, the main combustion zone and

burnout zone. And the law of its production is almost identical with

the combustion of coke. The combustion process of coke is

accompanied with the production of char NO. Due to the air staged,

the formation rate of NO was higher near the first and two layer

burners in the main combustion zone. Then due to the insufficient

oxygen and more CO, reducing state is better, resulting in a reduction

of the rate of char NO, and some NO is reduced.

From figure 11 it can be seen that in the burnout zone because of

the SOFA input, unburned char began to burn fully, it is also

accompanied by the generation of a large amount of char NO. So

oxygen has a great influence on the formation of char NO.

3.3.3 Production

Law of

Fuel NO

From the formation mechanism of fuel NO

x in figure 4, during the

actual generation of fuel NO, the volatile NO and char NO are

mutually influenced, especially the intermediate product HCN and

NHi when the volatile N is converted to NO, which has a great

influence on the reduction of the char NO. The above methods can

only be qualitative analysis of the distribution of the law, and can

reflect the real law of fuel NO

It is still necessary to overall analysis

of the various factors affecting the fuel NO

. 0 10 20 30 40

-1.50x10-6 0.00

1.50x10-6 3.00x10-6 4.50x10-6 6.00x10-6 7.50x10-6 Fuel NO Rate O2

High /m Fuel NO Rate /kgmolm-3s-1 02468 O2 /%

Fig. 12 The section average value of fuel NO rate and O

2 0 10 20 30 40 0

120

150 Fuel NO

High /m Fuel NO /L/L 0369

12 CO/%

Fig. 13 The section average value of fuel NO and CO

Figure 12 and 13 are the distribution of

2 and CO and fuel NO

in each section of the furnace. It can be seen that the combustion is

weak in hopper area duo to less oxygen, and a large amount of CO is

generate

d, and fuel NO production is very small. The formation rate

of the fuel NO is even negative, which shows that the NO diffused

from the main combustion zone is reduced here.

Around the first layer and the second layer of the burners in the

main combustion zone, due to the input of coal and adequate oxygen, the volatile is volatilized and rapid combustion, while some char is

burned. So a large amount of volatile NO and char NO generated, the

total fuel NO generation rate is very large. Between these two layers

of burners, the amount of oxygen is consumed, which is not

conducive to the formation of NO. And the amount of CO is more, so

the reduction is strong, and the generated NO is reduced. The yield of

fuel NO is decreased, and the production rate of fuel NO in some

areas is negative.

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Frontiers in Heat and Mass Transfer (FHMT), 8, 3 (2017)

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In the vicinity of the third layer burner, only a small amount of

oxygen is put into furnace, and no coal. Although the oxygen content

increased, but the amount of CO is still very high, is not conducive to

the formation of NO. Therefore, the production of fuel NO is very

small in this vicinity

In the burnout zone, due to the inputs of SOFA,

the oxygen

content increased rapidly, CO was rapidly oxidized, so the amount of

CO decreased rapidly. In the main combustion zone due to lack of

oxygen, pulverized coal combustion is not fully, which can be fully

burned in the burned zone, and accompanied by a small amount of

volatile NO and a lot of char NO

3.4 The

Effect of the

Distribution of

Oxygen in the

Main

Combustion

Zone on NO

Table 2 Air distribution parameters and NO

x output of furnace outlet

Case 1 Case 2 Case 3

The ratio of primary air

21.54 21.54 21.54

The ratio of SOFA

34.98 34.98 34.98

The secondary air ratio of the first layer

18.22 20.00 16.50

The secondary air ratio of the second layer

18.74 16.96 20.46

The secondary air ratio of the third layer /% 6.52 6.52 6.52

x output of furnace outlet /mg·Nm

3 215.23 231.56 217.78

Keep the total air volume, total amount of coal and primary air are

the same. When the SOFA ratio is 34.98%, by adjusting the

secondary air ratio of the first and second layer of burners, analyse

the effect of the distribution of oxygen in the main combustion zone

on the thermal NO

x and fuel NO

x. Specific distribution of air and

x output of furnace outlet are shown in

Table 2: 0 10 20 30 40

1100

1200

1300

1400

1500

1600 Temperature /K

High /m

Case 1

Case 2

Case 3

Fig.

4 The section average value of temperature 0 10 20 30 40

0.0

5.0x10-8 1.0x10-7 1.5x10-7 2.0x10-7 2.5x10-7 Thermal NO Rate /kgmolm-3s-1

High /m

Case 1

Case 2

Case 3

Fig.

5 The section average value of thermal NO rat

Figure 14 is

the section average value of temperature with the

furnace height under these three conditions. It can be seen from the

figure, as compared with the other two conditions

, case

3 input more

secondary air through the second layer burner

s, and case 3 has a

relatively high temperature in the main combustion zone and burnout

zone, so the thermal NO yield is relatively high. It can be seen clearly

from the generation rate of thermal NO in

figure 15, and the thermal

NO rate in working condition 3 is relatively large

r. But the thermal

NO is relatively small for total NO yield, and the temperature

difference between these three conditions is not very large, the

thermal NO rate is also in the same order of magnitude, so the three

conditions of the heat type NO production is not large. Therefore,

there is only a little of difference of thermal NO production among

these three kinds of operating. The thermal NO can only be used as

reference, and the decisive factor is the fuel NO.

And from the distribution of oxygen in figure 16 can be seen

that, under the air staged combustion only near the burner oxygen is

Page 7 of 8

Frontiers in Heat and Mass Transfer (FHMT), 8, 3 (2017)

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Comprehensive analysis of the fuel type NO formation factors

and reduction factors, it is not difficult to get out, case 2 due to the

worst

reducibility, so that the furnace outlet NO

x production is

relatively more. In order to reduce NO

x emissions at furnace exit, the

distribution of oxygen in the main combustion zone must be

reasonable based on the control of the SOFA ratio. The first layer of

the air flow can

t be too much, in order to enable the main

combustion zone form a good

reducibility, reducing the NO

production. 5 10 15 20 25 30 35

0.0

2.0x10-6

4.0x10-6

6.0x10-6 Fuel NO Rate /kg×mol×m-3×s-1

High /m

Case 1 Case 2 Case 3

Fig.

8 The section average value of fuel NO rat

4. CONCLUSION

The

n of thermal NO and fuel type NO emission under the

air staged combustion in a tower pulverized coal fired boiler

. Based on the detailed analysis, the following conclusions

can be drawn:

(1) Air staged combustion is beneficial to reduce the NO

x output

of the main combustion zone, so as to reduce the NO

emission from the furnace outlet. There is an optimal value of

SOFA ratio, and the yield of NO

x under this condition is the

minimum.

(2) Thermal NO can only be produced at high temperature, and it

is affected by oxygen. When the oxygen is sufficient under

high temperature, thermal NO can be produced in a large

amount; when the oxygen is insufficient, even if the

temperature is appropriate, there will not be thermal NO

formation.

(3) The volatile matter of NO is mainly near the burners in the

main combustion zone. If air supply mode of burner is

different, the distribution of volatile NO is also slightly

different.

(4) The oxidation of char N is closely related to oxygen, and is

affected by CO. The more oxygen, the more char NO

production. When the amount of CO is more, some char NO

will be reduced.

(5) A large amount of fuel NO will be generated near the burners

in the main combustion zone. But the main combustion zone

is in the negative oxygen combustion, a lot of generated NO is

reduced. In the burnout zone due to unburned pulverized coal

burning again, a large amount of fuel NO will be produced.

(6) In order to reduce NO

x emissions at furnace exit, the

distribution of oxygen in the main combustion zone must be

reasonable based on the control of the SOFA ratio. The first

layer of the air flow can

ot be too

h, in order to enable the

main combustion zone form a good reducibility, reducing the

x production.

ACKNOWLEDGEMENTS

This work was financially supported by National Natural Science

Foundation of China (No. 51476103), Public welfare scientific

research projects of Shanghai Municipal Bureau of Quality and

Technical Supervision (No. 2012

-41), Innovation Program of

Shanghai Municipal Education Commission (No. 14ZZ134) and

Shanghai Pujiang Program (No. 14PJ1407000).

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