JP2001041413A - Liquid fuel burning burner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid fuel burning burner capable of preventing a furnace inner wall from being corroded at high temperature. SOLUTION: The present burner includes a primary air flow passage 6 formed at the center of a burner body 102 and at least single or more annular air flow passages 6, 7 surrounding the primary air flow passage 6, and further a flame insulator 13 provided at the tip center of the primary air flow passage 6. There is mounted a burner gun 12, to which an atomizer 12a is attached, on the tip end of the flame insulator penetrating the center of the flame stabilizer 13. The burner is mounted on a corner of a boiler furnace or on a wall surface of the same wherein a liquid fuel and combustion air are injected tangentially with respect to an imaginary circle set in the boiler furnace to demonstrate swirling combustion. There is provided a side air injection hole 109b outside the air flow passages 6, 7 along a wall surface in the upper and lower left and right directions or in the direction of the entire periphery of the fire furnace inner wall surface. The fuel and air are blown in between a flame and the furnace inner wall surface from the side air injection hole 109b to raise oxygen concentration of the combustion gas in contact with the furnace inner wall surface.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid fuel-fired burner applied to a liquid fuel-fired boiler for generating steam for power generation or for factories.

[0002]

2. Description of the Related Art FIG. 10 is a system diagram showing an example of a boiler for explaining the prior art, FIG. 11 is a longitudinal sectional view of a conventional liquid fuel-fired burner (main burner), and FIG. FIG. As shown in FIGS. 10 to 12, the combustion air 20 is supplied to the burner wind box 1 by a forced air blower 17 (FDF).
In the meantime, the air is heated and exchanged with the flue gas 22a separately sent in the air heater 19 to be heated. Further, the combustion air 20 is supplied to a combustion exhaust gas 22 by a recirculating exhaust gas ventilator 24 (GRF).
A part of the recirculated exhaust gas 23 (GR) branched from a is mixed as the recirculated exhaust gas 25 for air mixing (GM),
The mixed combustion air 27 is obtained.

The GM-mixed combustion air 27 is divided into burner combustion air 28 and additional air 29 (AA) before being sent to the burner wind box 1. Burner combustion air 2
8 is sent to the burner wind box 1 and blown from the burner body 2 into the furnace interior 16a for combustion. The burner main body 2 is provided with a circular primary air flow path 6 at the center of the burner.
A burner gun 12 is mounted at the center of the primary air passage 6. An atomizer 12a is attached to the tip of the burner gun 12, and a flame stabilizer 13 is provided so as to surround the atomizer 12a.

A secondary air cylinder 4 is arranged in the burner body 2 so as to surround the primary air cylinder 3 forming the primary air flow path 6 therein. An air cylinder 5 is arranged. An annular secondary air flow path 7 is formed between the primary air cylinder 3 and the secondary air cylinder 4, and an annular tertiary air flow path 8 is provided between the secondary air cylinder 4 and the tertiary air cylinder 5. Are formed. A primary air damper 9, a secondary air damper 10, and a tertiary air damper 11 are provided at the inlets of the flow paths 6, 7, and 8, respectively, for adjusting air flow rates. The tip side of the burner body 2 is attached to the furnace body 16 by a burner attachment plate 2a fixed to the tip of the tertiary air cylinder 5 on the outermost periphery. The burner combustion air 28 sent into the burner wind box 1 is divided into a primary air 28a, a secondary air 28b and a tertiary air 28c.
After being sent into the primary air flow path 6, the secondary air flow path 7 and the tertiary air flow path 8, respectively, through the passages 10 and 11, the liquid is blown into the furnace 16a and separately blown into the furnace 16a. Used for fuel combustion. Note that reference numeral 26 in FIG.
Represents furnace bottom recirculated exhaust gas (BGR) blown into the bottom of the furnace 16a.

[0005] The liquid fuel 21 is pressure-fed to a burner gun 12 from a liquid fuel supply device (not shown) and is supplied to an atomizer 12a.
Is sprayed into the furnace 16a, and is ignited by an ignition source (not shown) to form a flame 31. The spread angle of the flame 31 depends on the fuel spray angle of the atomizer 12a and the secondary air 28b.
In the case of the burner performing the swirling combustion in the furnace 16a, the angle is approximately 70 ° to 90 ° (the ejection angle of 35 ° to 45 ° with respect to the burner axis).

When the primary air 28a is blown into the furnace 16a from the primary air flow path 6, the flame 31 is formed on the back of the flame stabilizer 13 provided at the outlet of the primary air flow path 6. The ignition point is stabilized by the circulating flow. Primary air 28a
Is consumed for combustion near the ignition point of the flame 31, and the secondary air 28 b and the tertiary air 28 c are consumed for combustion in the combustion zone of the burner body 2 while diffusing and mixing with the entire flame 31. Normally, the burner combustion air 28 is supplied in an amount smaller than the theoretical combustion air amount relative to the amount of the liquid fuel 21 separately supplied, and a reducing atmosphere is formed in the combustion zone below the AA port 15 from the burner body 2. , Liquid fuel 2
1 reduces nitrogen oxides (hereinafter abbreviated as NOx) in the combustion gas 22 generated by the combustion. In addition, liquid fuel 2
Combustibles remain in the combustion gas 22 generated by the combustion of No. 1 due to lack of air.

On the other hand, the AA 29 diverted from the GM-mixed combustion air 27 upstream of the burner wind box 1 is
Is blown into the furnace 16a to be used for combustion of the remaining combustibles in the combustion gas 22 to complete the combustion. After the combustion gas 22 that has completed combustion is sent to the evaporating tube group 30 to heat the steam, the combustion gas 22 is drawn as the combustion exhaust gas 22 through the air heater 19 and the like by the induction ventilator 18 (IDF) and discharged out of the boiler.

FIG. 13 is a plan sectional view at the center height of the burner main body 2 for explaining an example of swirling combustion when the burner main body 2 is provided at a corner portion of the furnace main body 16. In FIG. 13, the burner body 2 provided at each corner blows the liquid fuel 21 and the burner combustion air 28 in a tangential direction with respect to an imaginary circle 32 set at the center of the furnace 16a to form a flame 31. Let it. The formed flames 31 interfere with each other, swirl and burn while forming a flame vortex, and ascend in the furnace 16a. The burner combustion air 28 blown from the burner body 2 is blown at a high flow rate in order to enhance the diffusion effect with the liquid fuel 21. The flow of the burner combustion air 28 blown at a high flow velocity generates a negative pressure between the walls of the furnace 16a, and the flame 31 is drawn toward the wall of the furnace 16a (a kind of Coanda effect). As a result, the wall surface of the furnace interior 16a near the burner main body 2 is exposed to the high-temperature reducing combustion gas.

It is generally known that when the oxygen concentration is low and hydrogen sulfide (H2S) is generated by incomplete combustion, it reacts with iron at a high temperature to form sulfide (sulfide corrosion).
The wall surface of the furnace 16a is made of a steel pipe. If the reduction combustion is continued in this state, the wall surface near the burner main body 2 always has a risk of high-temperature corrosion.

[0010]

As described above, a reducing atmosphere is formed in the combustion zone of the burner main body 2 as a measure for reducing NOx of the swirling combustion type boiler, and NOx generated by the combustion of the liquid fuel 21 is reduced, and the additional atmosphere is reduced. A combustion method in which combustion is completed by blowing air 29 (AA) is employed. However, in the conventional liquid fuel-fired burner, it is inevitable that high-temperature combustion gas is exposed to the furnace inner wall composed of steel pipes, and hydrogen sulfide and the like are generated in the high-temperature gas during combustion performed in the high-temperature reducing atmosphere zone. Thus, there is a problem that the furnace inner wall surface is damaged by high-temperature corrosion.

The present invention has been made in view of the above-mentioned problems of the prior art, and has as its object to provide a liquid fuel-fired burner capable of preventing high-temperature corrosion of the furnace inner wall.

[0012]

According to the present invention, a primary air flow path is formed at the center of a burner body, and at least a single air flow path surrounds the primary air flow path. An annular air flow path is formed, and further, a flame stabilizer and a burner gun penetrating the flame stabilizer are provided at the center end of the primary air flow path, and the flame stabilizer is mounted on a corner or wall of a boiler furnace, Inject fuel and combustion air tangentially to the virtual circle set in the boiler furnace,
In a liquid fuel-fired burner that performs swirling combustion, outside the air passage, a side air injection port that blows side air along the wall surface in the vertical and horizontal directions or the entire circumferential direction of the furnace inner wall surface is provided with respect to the burner axis. It is characterized by being provided at an ejection angle of 45 ° to 75 °. Here, the burner main body is provided with a side air flow path for introducing side air to the side air ejection port, or the burner combustion air is branched to a side air intake of the side air flow path. To be introduced.

As described above, the flame of the burner main body provided at, for example, four corners in the furnace is formed to spread toward the furnace inner wall surface by swirling combustion, so that the furnace inner wall surface is exposed to high-temperature combustion gas. Easy to be. In addition, since the combustion zone of the burner body is in a reducing atmosphere and lacks air, high-temperature corrosion may occur. Therefore, in the present invention, side air (for example, air for branching burner combustion) is introduced into the side air intake port, and the side air passes through the side air flow path from the side air injection port to the flame and the furnace inner wall surface. The oxygen concentration of the combustion gas blown into the gap and in contact with the furnace inner wall surface can be increased.

Here, in plan view of the burner body, particularly, the inner wall surface of the furnace opposite to the turning direction of the flame, that is, the inner wall surface of the furnace downstream of the flame has a wide reach of the high-temperature combustion gas. It is necessary to blow a lot of side air compared to the part. Therefore, by providing a side air damper for adjusting the flow rate at the side air intake of the side air flow path, the side air damper is adjusted so that the side air outlet close to the furnace inner wall surface on the downstream side of the flame is provided. By setting the opening area larger than the opening area of the other side air ejection port, the blowing flow rate is increased. here,
The flow rate and flow rate of the side air blown to the downstream side of the flame are set so that the side air reaches a range sufficiently wider than the range of the downstream side wall surface of the high-temperature combustion gas.

According to a fifth aspect of the present invention, in a plan view of the burner main body, an opening area of a side air outlet near an inner wall surface of the furnace opposite to a turning direction of the flame is equal to an opening of another side air outlet. It is set to be larger than the area. That is, if the flame is swirling in the left direction, the ratio of the high-temperature reducing combustion gas reaching the wall surface located on the opposite side to the swirling direction of the flame, that is, on the right side (downstream of the flame), becomes large. The area of the side air ejection port is set so that the air blowing flow rate is particularly large on the downstream side of the flame. In addition, since the combustion gas from the flame expands on the upstream side wall surface of the flame, side air is blown at the same time, and since the flame tends to separate from the upstream side wall surface, side air blowing is performed. Set the volume to a small amount. Further, the amount of side air blown into the vertical wall surface of the flame is set to a small amount because the distance between the burners provided in the upper and lower stages is short.

[0016]

Next, embodiments of the present invention will be described with reference to the drawings. (First Embodiment) FIG. 1 is a longitudinal sectional view of a liquid fuel burning burner (main burner) of the present invention, FIG. 2 (a) is a sectional view taken along the line BB of FIG. 1, and FIG. It is a C line sectional view.

A primary air flow path 6 having a circular cross section is formed at the center of the burner of the burner body 102, and an annular secondary air flow path 7 is formed so as to surround the primary air flow path 6. An annular side air flow path 108 is formed so as to surround the secondary air flow path 7. These primary air flow path 6, secondary air flow path 7, and side air flow path 108
The primary air damper 9 for adjusting the flow rate, the secondary air damper 10 and the side air damper 111
Are provided respectively. A burner gun 12 is mounted at the center of the primary air flow path 6. An atomizer 12a is attached to the tip of the burner gun 12, and a flame stabilizer 13 is provided so as to surround the atomizer 12a.

The side air flow path 108 is formed between the secondary air cylinder 4 and the side air cylinder 105.
The distal ends of the next air cylinder 4 and the side air cylinder 105 are fixed to the burner mounting plate 102a, and a side air chamber 109 is formed at the distal end of the side air flow path 108. Burner body 1
02 is mounted to the furnace main body 16 by a burner mounting plate 102a. On the burner mounting plate 102a,
The side air chamber 109 penetrates through the burner mounting plate 102a.
And a plurality of side air ejection pipes 109a are provided. The end of the side air ejection pipe 109a penetrates a burner tile (fireproof material) 14 forming a burner throat 14a of the burner main body 102, and is provided with a side air ejection port provided to eject side air 128 toward the furnace interior 16a. 109b. Side air outlet 109b
Are arranged so that the side air 128 can be blown at a high flow rate of about 60 m / s or more along the vertical and horizontal wall surfaces at a position where the flame 31 does not come into contact with the flame 31 early on the outer periphery of the burner throat 14a.

The jet angle θ of the side air 128 from the side air jet port 109b with respect to the burner axis (see FIG. 1).
) Is 45 ° or more, which is more than the spread angle of the flame 31 (35 ° to 45 ° with respect to the burner axis), so that the side air 128 can contribute to combustion almost immediately. Reaches the furnace inner wall without oxygen. Further, in order to ensure that the side air 128 reaches the furnace inner wall surface and increase the concentration of combustion gas oxygen in contact with the wall surface, the ejection angle θ of the side air 128 with respect to the burner axis (see FIG. 1) is 45 ° to 75 °. Is preferable.

FIG. 3 shows that the burner main body 102 is connected to the furnace main body 16.
FIG. 3 is a plan cross-sectional view of the inside of the furnace 16a at the center height of the burner main body 102 when provided at the corner portion of FIG. Side air outlet 109b near the wall surface of furnace 16a on the opposite side to the turning direction of flame 31 (in this example, counterclockwise direction) with respect to burner body 102 in plan view
The opening area of the left side air outlet (in FIG. 2A) is set larger than the opening area of the other side air outlet 109b. That is, if the flame 31 is swirling in the left direction, the ratio of the high-temperature reducing combustion gas reaching the wall surface side (flame downstream side) located on the right side (flame downstream side) of the flame 31 increases, so that the side air 128 The area of the side air outlet 109b is set such that the blow flow rate is particularly larger on the flame downstream side 128a than on the flame upstream side 128b.

Next, the operation will be described. The burner combustion air 28 sent into the burner wind box 1 is blown into the furnace 16a from the burner main body 102 to be burned. That is, the burner combustion air 28 sent into the burner wind box 1 is adjusted by the dampers 109, 110, 111 provided at the inlets of the flow paths 6, 7, 108 so as to have a predetermined air amount. Thereafter, they are sent to the primary air flow path 6, the secondary air flow path 7, and the side air flow path 108, respectively. The primary air 28a and the secondary air 28b are used for the combustion of the liquid fuel 21 separately fed by the same operation as in the case of the above-described conventional liquid fuel-fired burner, and the air is insufficient in the combustion zone of the furnace 16a. Swirling combustion is performed.

As shown in FIG. 3, the flames 31 of the burner body 102 provided at the four corners of the furnace 16a are formed by swirling combustion and spread toward the wall of the furnace 16a. And it is exposed to reducing combustion gas. On the other hand, the side air 128 branched in the burner wind box 1 is sent into the side air chamber 109 from the annular side air flow path 108 through the side air damper 111.

The side air 128 sent into the side air chamber 109 is subjected to a flame from a side air jet pipe 109a provided on the burner mounting plate 102a and a side air jet port 109b provided therethrough through the burner tile 14 therebelow. The oxygen concentration of the combustion gas blown into the space between the furnace wall 16a and the furnace wall 16a is increased. That is, side air (for example, a branch of the burner combustion air 28) is introduced into the side air intake, and the side air passes through the side air flow path 108 from the side air outlet 109b to the flame 31 and the furnace interior 16a. Blown between the walls, inside the furnace 1
6a The oxygen concentration of the combustion gas in contact with the wall surface can be increased. Therefore, even in the combustion method performed in the high-temperature reducing atmosphere zone, hydrogen sulfide and the like are hardly generated in the high-temperature gas, and the furnace inner wall surface is hardly damaged by high-temperature corrosion, and the life is extended. In addition, the side air 128 is in the furnace 1
Since it is ejected along the wall 6a, it hardly contributes to combustion.

Here, the side air dampers 111 for adjusting the flow rate corresponding to the respective side air outlets 109b are adjusted so that the opening area of the side air outlet closer to the wall surface of the furnace 16a downstream of the flame 31 is changed. By setting the opening area larger than the opening area of the side air outlet, the blow flow rate is increased. Of course, the flow rate and flow rate of the side air blown to the downstream side of the flame 31 are set to a size that allows the side air to reach a range sufficiently wider than the range of the downstream side wall surface of the high-temperature combustion gas. Further, as described above, if the flame 31 is swirling in the left direction, the arrival ratio of the high-temperature reducing combustion gas to the wall surface (the flame downstream) located on the right side (the flame downstream) of the flame 31 becomes large. And the side air injection port 109b so that the side air blowing flow rate is particularly large downstream of the flame.
Are set. It should be noted that the combustion gas from the flame 31 extends at the same time on the wall surface of the furnace 16a on the upstream side of the flame 31 and that side air is blown at the same time, and the flame 31 is separated from the wall surface of the furnace 16a on the upstream side. By being slightly, the blowing amount of the side air is set to a small amount, and the blowing amount of the side air to the vertical wall surface of the flame 31 is the distance between the burners provided in the upper and lower stages (see FIG. 10). May be set to a small amount.

Burner body 102 and side air 128
Is adjusted so that the air ratio of the combustion zone of the burner body 102 does not become 1 or more. However, when the reducing atmosphere in the combustion zone of the burner main body 102 cannot be maintained due to the combustibility due to the decrease in the boiler load, the air ratio may be greater than 1, but the blowing amount of the side air 128 may be as small as possible. A state equivalent to 100% load is maintained.

The NOx in the combustion gas 22 generated by the combustion of the liquid fuel 21 is not reduced by the reduction combustion in the combustion zone of the burner body 102, but is replaced by N
Intermediate products such as H3 and HCN are generated. In addition, combustibles remain in the combustion gas 22 due to insufficient air combustion. The combustion gas 22 discharged from the combustion zone of the burner body 102 is supplied to an additional air (AA) port 1.
Oxidizing combustion is performed by the AA 29 blown from 5. The oxidizing combustion by the AA 29 is performed while completely combusting the remaining combustibles in the combustion gas 22 and suppressing the generation of NOx caused by the combustion of the remaining combustibles and the oxidation of the intermediate products as low as possible. However, even in this case, as described above, the side air 128
It is necessary to secure a particularly large blowing amount. In addition, the side air is not limited to being blown along the inner wall of the furnace in the vertical and horizontal directions of the inner wall of the furnace, but the side air outlets may be arranged uniformly on the circumference to cover the entire circumferential direction of the inner wall of the furnace. Then, side air may be blown along the furnace inner wall surface.

(Second Embodiment) FIG. 4 is a longitudinal sectional view of a second embodiment of a liquid fuel burning burner according to the present invention, FIG. 5 (a) is a sectional view taken along line BB of FIG. 4, and FIG. FIG. 5 is a sectional view taken along line CC of FIG. 4.

An annular side air inlet header 133 is provided on the outer periphery of the secondary air cylinder 4 of the burner main body 102, and a side air inlet header 133 is provided at the inlet of the side air inlet header 133 for taking in the side air 128 and adjusting the flow rate. An air damper 111 is provided. A plurality of side air flow pipes 134 extending in the axial direction of the burner main body 102 are attached to the outlet side of the side air inlet header 133, and the downstream end of the side air flow pipe 134 is connected to the side air chamber 109. , The inside of the side air flow path pipe 134 is used as the side air flow path 108. With such a configuration, the side air 128 is sent to the side air inlet header 133 through the side damper 111, and the side air 128
34 from the side air flow path 108 to the side air chamber 109.
To reach. As described above, the second embodiment differs from the first embodiment in that the shape of the side air flow path 108 and the side air inlet header 133 are provided in the intake portion of the side air 128.

(Third Embodiment) FIG. 6 is a vertical sectional view of a third embodiment of a liquid fuel burning burner according to the present invention, FIG. 7 (a) is a sectional view taken along the line BB of FIG. 5, and FIG. 5 is a cross-sectional view taken along line CC.
(C) is a sectional view taken along line DD of FIG. 5.

The side air flow path 108 provided on the outer periphery of the secondary air cylinder 4 is divided into at least two in the circumferential direction by a side air dividing plate 108a extending along the side air flow path 108 (in this example, the side air flow path 108 is divided into two parts). 4), a side air damper 111 is provided at the entrance of each divided side air flow path 108.
Is provided. The side air chamber 109 is also divided by the side air chamber dividing plate 109c into the same number as the side air passages 108, and the corresponding side air passage dividing plates 10
8a and the side air chamber dividing plate 109c are connected. That is, the inside of the side air chamber 109 is divided by the side air chamber dividing plate 109c into the same number as the side air passages 108, and the side air passage dividing plate 108c and the side air chamber dividing plate 109c are connected to form the side air Damper 111, side air flow path 108, side air chamber 1
09 (four in this example) are provided, and the flow rates of the side air 128 blown from the divided side air chambers 109 through the side air outlets 109b penetrating into the furnace 16a are respectively adjusted. It can be adjusted arbitrarily.

As described above, in the third embodiment, the side air flow path 108 and the side air chamber 109 are divided in the burner main body 102 of the first embodiment, and a desired side air flow path 108 is formed by the side air damper 111. By closing, the side air 128 can be blown from an arbitrary side air outlet 109b, and the flow rate distribution can be arbitrarily adjusted. As a result, the inside of the furnace 16
The flow rate of the side air 128 blown by the side air jet port 109b penetrated into a can be arbitrarily adjusted.

(Fourth Embodiment) FIG. 8 is a vertical sectional view of a fourth embodiment of a liquid fuel burning burner according to the present invention, FIG. 9 (a) is a sectional view taken along line BB of FIG. 8, and FIG. 8 is a sectional view taken along line CC of FIG. An annular side air inlet header 133 is provided on the outer periphery of the secondary air cylinder 4.
33 is divided into at least two or more (four in this example) by the side air inlet header dividing plate 133a, and the side air damper 11 is provided at each of the divided inlet headers 133.
1 is provided. The side air chamber 109 is also divided by the same method as that of the third embodiment, that is, the same number as the side air inlet headers 133 by the side air chamber dividing plate 109c, and the divided side air inlet headers 133 are respectively divided.
The side air chamber 109 is communicated with the side air chamber 109 by a side air flow pipe 134. As a result, it is possible to arbitrarily adjust the flow rate of the side air 128 blown from the divided side air chamber 109 through the side air ejection port 109b penetrating into the furnace 16a. As mentioned above,
In the fourth embodiment, the side air inlet header 133 and the side air chamber 1 of the burner body 102 of the second embodiment are used.
09 is divided and the corresponding compartments are connected by a side air flow path pipe 134, and the side air 128
Can be blown only from a given arbitrary side air outlet 109b to an arbitrary wall surface, or the flow rate distribution can be adjusted arbitrarily.

[0033]

Since the present invention is constructed as described above, a part of the combustion air from the side air injection port is used as side air to apply an arbitrary amount between the flame and the furnace inner wall surface to an arbitrary wall surface. Since the gas can be blown, the oxygen concentration of the combustion gas in contact with the furnace inner wall surface is increased, and high-temperature corrosion can be prevented.

In particular, since the furnace inner wall surface on the downstream side of the flame has a wider reach of the high-temperature combustion gas, a larger amount of side air is required as compared with the other parts. Preferably, the flow rate is adjusted. The adjustment of the flow rate and the flow velocity can be easily set by the opening and closing of the damper and the opening area of the side air ejection port.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a first embodiment of a liquid fuel burning burner of the present invention.

2A is a sectional view taken along line BB of FIG. 1, and FIG. 2B is a sectional view taken along line CC of FIG.

FIG. 3 is a sectional view of the boiler furnace main body according to the present invention cut along a horizontal plane.

FIG. 4 is a longitudinal sectional view of a second embodiment of the liquid fuel fired burner of the present invention.

5A is a sectional view taken along line BB of FIG. 4, and FIG. 5B is a sectional view taken along line CC of FIG.

FIG. 6 is a longitudinal sectional view of a third embodiment of the liquid fuel burning burner of the present invention.

7A is a sectional view taken along line BB of FIG. 6, FIG. 7B is a sectional view taken along line CC of FIG. 6, and FIG. 7C is a sectional view taken along line DD of FIG.

FIG. 8 is a longitudinal sectional view of a fourth embodiment of the liquid fuel fired burner of the present invention.

9A is a sectional view taken along line BB of FIG. 8, and FIG. 9B is a sectional view taken along line CC of FIG.

FIG. 10 is a system diagram showing an example of a boiler for explaining a conventional technique.

FIG. 11 is a vertical sectional view of a conventional liquid fuel-fired burner.

12 is a view as viewed in the direction of the arrow a in FIG. 11;

FIG. 13 is a cross-sectional view of a conventional boiler furnace main body cut along a horizontal plane.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Burner wind box 2 Burner main body 3 Primary air cylinder 4 Secondary air cylinder 6 Primary air flow path 7 Secondary air flow path 9 Primary air damper 10 Secondary air damper 12 Burner gun 12a Atomizer 13 Flame stabilizer 14 Burner tile 14a Burner throat 15 Additional air (AA) port 16 Furnace main body 16a Inside the furnace 17 Indentation blower (FDF) 18 Induction blower (IDF) 19 Air heater 20 Combustion air 21 Liquid fuel 22 Combustion gas 22a Combustion exhaust gas 23 Recirculated exhaust gas ( GR) 24 Recirculated exhaust gas ventilator (GRF) 25 Recirculated exhaust gas for air mixing (GM) 26 Furnace bottom recirculated exhaust gas (BGR) 27 GM mixed combustion air 28 Burner combustion air 29 Primary air 28b Secondary air 29 Additional air (AA) 30 Evaporation tube bank 31 Flame 32 Virtual circle 102 Ba Main body 102a Main burner mounting plate 108 Side air flow passage 108a Side air flow passage dividing plate 109 Side air chamber 109a Side air ejection pipe 109b Side air ejection outlet 109c Side air chamber division plate 111 Side air damper 128 Side air 133 Side air inlet Header 133a Side air inlet header dividing plate 134 Side air flow pipe

Continued on the front page (72) Inventor Masashi Hishida 2-5-1 Marunouchi, Chiyoda-ku, Tokyo Sanshi Heavy Industries Co., Ltd. (72) Inventor Masaharu Oguri 5-717-1 Fukahori-cho, Nagasaki-shi, Nagasaki Pref. Company F term (reference) 3K052 GA10 GB01 GB04 GC01 GE05 GE08 HA01 3K091 AA18 AA20 BB02 BB36 CC02 CC22 DD06 EC06 EC13 EC23

Claims (5)

[Claims] 1. A primary air flow path is formed in a central portion of a burner main body, and at least a single or more annular air flow path is formed surrounding the primary air flow path.
A flame stabilizer and a burner gun penetrating the flame stabilizer were provided at the center end of the primary air flow path, and were mounted on a corner or wall of a boiler furnace, and liquid fuel and combustion air were set in the boiler furnace. In a liquid-fuel-fired burner that tangentially blows and performs swirling combustion with respect to an imaginary circle, side air is blown along the wall surface in the vertical and horizontal directions or the entire circumferential direction of the furnace inner wall surface outside the air passage. A liquid fuel-fired burner, wherein the side air ejection port is provided at an ejection angle of 45 ° to 75 ° with respect to the burner axis. 2. The liquid fuel-fired burner according to claim 1, wherein the burner main body is provided with a side air passage for introducing side air into the side air outlet. 3. The burner according to claim 2, wherein the burner combustion air is branched and introduced into a side air intake of the side air flow path. 4. The liquid fuel fired burner according to claim 3, wherein a side air damper for adjusting a flow rate is provided at a side air intake of the side air flow path. 5. An opening area of a side air ejection port near an inner wall surface of a furnace opposite to a turning direction of the flame in a plan view of the burner main body is set to be larger than an opening area of another side air ejection port. The liquid fuel-fired burner according to claim 1.