JP2022130326A - Burner - Google Patents

Abstract

To reduce nitrogen oxide in an exhaust gas.SOLUTION: A burner 100 comprises: a first injection unit 110 which includes one or a plurality of first injection ports (a fuel injection port 112c and a mixture gas injection port 114c) provided toward the internal space of a furnace; a second injection unit 130 which is spaced apart from the first injection port(s) and includes one or a plurality of second injection ports 138a and 138b provided toward the internal space of the furnace; a first supplying unit 120 that supplies, to the first injection unit 110, a fuel gas containing at least ammonium, and an oxidizer gas that is equal to or greater than 1/3 and equal to or smaller than 2/3 of an aiming oxidizer amount which is equal to or greater than a theoretical oxidizer amount relative to the fuel gas; and a second supplying unit 140 that supplies, to the second injection unit 130, the oxidizer gas by what corresponds to a difference between the amount of the oxidizer gas supplied to the first injection unit 110 and the aiming oxidizer amount.SELECTED DRAWING: Figure 1

Description

The present invention relates to a burner for burning ammonia.

In recent years, in order to prevent global warming, a reduction in CO ₂ (carbon dioxide) emissions has been demanded. Therefore, technology for burning ammonia in addition to fossil fuels is attracting attention (for example, Patent Document 1).

Japanese Patent Application Laid-Open No. 2020-112280

When ammonia is burned, there is a problem that the concentration of nitrogen oxides in the exhaust gas increases compared to when only fossil fuel is burned.

SUMMARY OF THE INVENTION An object of the present invention is to provide a burner capable of reducing nitrogen oxides in exhaust gas.

In order to solve the above problems, the burner of the present invention includes a first injection part including one or a plurality of first injection ports provided toward the interior space of the furnace, and an interior space of the furnace separated from the first injection port. fuel gas containing at least ammonia; and 1/3 or more and 2/3 of the target oxidizer amount equal to or greater than the theoretical oxidizer amount for the fuel gas. a first supply unit that supplies the following oxidizing gas to the first injection unit; and a second supply unit that supplies to the.

Further, the flow velocity ratio a/b between the flow velocity a of the fuel gas and the oxidant gas injected from the first injection port and the flow velocity b of the oxidant gas injected from the second injection port is 0.05 or more. may

Also, the first injection port may include a fuel injection port for injecting the fuel gas and an oxidant injection port for injecting the oxidant gas.

Also, the first injection port may inject a mixed gas containing the fuel gas and the oxidant gas.

In order to solve the above problems, another burner of the present invention includes a first injection part including one or a plurality of first injection holes provided toward the interior space of the furnace; a second injection section including one or more second injection ports provided toward the internal space of the first supply section for supplying a fuel gas containing at least ammonia and an oxidant gas to the first injection section; a second supply section for supplying the oxidizing gas to the second injection section, the flow rate a of the fuel gas and the oxidizing gas injected from the first injection port, and the oxidizing gas injected from the second injection port; The flow velocity ratio a/b to the flow velocity b of is 0.05 or more.

The first injection part has one first injection port, and the distance between the first injection part and the second injection part is 1.85 to 6.0 times the diameter of the first injection port. may be less than

Further, the first injection part has a plurality of first injection holes, and the distance between the first injection part and the second injection part is the center of two first injection holes in the plurality of first injection holes. It may be 1.85 times or more and less than 6.0 times the length of the longest virtual straight line among the connecting virtual straight lines.

According to the present invention, it becomes possible to reduce nitrogen oxides in the exhaust gas.

It is a figure explaining the burner concerning this embodiment. It is the figure which looked at the injection port of the 1st injection part, and the injection port of the 2nd injection part from the interior space side of the furnace. FIG. 4 is a diagram illustrating the relationship between the ratio of air supplied by the first supply unit and the amount of NOx contained in the exhaust gas; FIG. 4 is a diagram for explaining the relationship between the flow velocity ratio between the flow velocity of the mixed gas jetted from the first injection section and the flow velocity of the air jetted from the second injection section, and the amount of NOx contained in the exhaust gas. FIG. 4 is a diagram showing the relationship between the distance between the first injection part and the second injection part and the diameter of the mixed gas injection port, and the relationship between the concentration of NOx in the exhaust gas.

Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. The dimensions, materials, and other specific numerical values shown in these embodiments are merely examples for facilitating understanding of the invention, and do not limit the invention unless otherwise specified. In the present specification and drawings, elements having substantially the same function and configuration are given the same reference numerals to omit redundant description, and elements that are not directly related to the present invention are omitted from the drawings. do.

[Burner 100]
FIG. 1 is a diagram illustrating a burner 100 according to this embodiment. As shown in FIG. 1, the burner 100 is provided on a furnace wall 10 that constitutes a furnace (for example, a furnace that constitutes a boiler). The burner 100 burns fuel gas containing at least ammonia. The fuel gas may contain only ammonia, or may contain hydrocarbons and the like in addition to ammonia. Hydrocarbons are methane, ethane, propane, butane, and the like.

Burner 100 includes a first injection section 110 , a first supply section 120 , a second injection section 130 and a second supply section 140 .

The first injection part 110 is provided toward the interior space of the furnace. The first injection part 110 injects fuel gas and oxidant gas. Here, the case where the oxidant gas is air will be taken as an example. In this embodiment, the first injection part 110 has a fuel injection nozzle 112 and a first oxygen-containing gas injection nozzle 114 .

The fuel injection nozzle 112 is a nozzle that injects fuel gas. The fuel injection nozzle 112 includes a main body 112a, a fuel supply pipe 112b, and a fuel injection port 112c (first injection port). The main body 112a is a cylindrical tubular body. The central axis of the main body 112a intersects (here, substantially perpendicular to) the furnace wall 10 .

A fuel supply pipe 112b is connected to the rear portion of the main body 112a (the portion of the main body 112a opposite to the furnace wall 10 side (the left side in FIG. 1, hereinafter referred to as the "rear end")). A fuel injection port 112c, which is an opening, is formed at the tip of the main body 112a (on the furnace wall 10 side (the right side in FIG. 1) of the main body 112a, hereinafter referred to as the "tip"). The fuel injection port 112c faces the interior space of the furnace.

The first oxidant gas injection nozzle 114 is a nozzle that injects a mixed gas containing fuel gas and air (primary air). The first oxidant gas injection nozzle 114 has a main body 114a, a first oxidant supply pipe 114b, and a mixed gas injection port 114c (first injection port). The main body 114a is a cylindrical tubular body. The main body 114a is arranged coaxially with the main body 112a of the fuel injection nozzle 112 so as to surround the main body 112a. That is, the main body 112a of the fuel injection nozzle 112 and the main body 114a of the first oxidizing gas injection nozzle 114 form a double cylindrical structure. FIG. 1 shows an example in which the tip portion 114d located on the furnace wall 10 side (the right side in FIG. 1, hereinafter referred to as the “tip”) of the main body 114a has a shape in which the diameter gradually decreases toward the tip. The shape of the first oxygen-containing gas injection nozzle 114 is not limited to this.

A first oxidant supply pipe 114b is connected to the rear portion of the main body 114a (the portion of the main body 114a opposite to the furnace wall 10 side (the left side in FIG. 1, hereinafter referred to as the "rear end")). The rear end of the main body 114 a is positioned closer to the furnace wall 10 than the rear end of the main body 112 a of the fuel injection nozzle 112 .

A mixed gas injection port 114c, which is an opening, is formed at the tip of the main body 114a. The mixed gas injection port 114c faces the interior space of the furnace.

In this embodiment, the fuel injection port 112c of the fuel injection nozzle 112 is provided so as to be positioned inside the main body 114a of the first oxygen-containing gas injection nozzle 114. As shown in FIG. That is, the mixed gas injection port 114c of the first oxidizing gas injection nozzle 114 is provided closer to the interior space of the furnace than the fuel injection port 112c of the fuel injection nozzle 112 is.

The first supply section 120 supplies fuel gas and air to the first injection section 110 . In this embodiment, the first supply section 120 includes a fuel supply system 122 and an oxidant supply system 124 . Fuel gas is supplied from the fuel supply system 122 into the main body 112a through the fuel supply pipe 112b. The fuel gas supplied into the main body 112a flows through the space within the main body 112a. The fuel gas that has passed through the main body 112a is injected from the fuel injection port 112c toward the space formed in the tip portion 114d of the main body 114a.

Air is supplied from the oxidant supply system 124 into the main body 114a through the first oxidant supply pipe 114b. The air supplied into the main body 114a flows through the space inside the main body 114a. Then, the air reaching the tip portion 114d of the main body 114a is mixed with the fuel gas injected from the fuel injection port 112c in the space inside the tip portion 114d. A mixed gas containing fuel gas and air is injected into the interior space of the furnace from the mixed gas injection port 114c.

Thus, the mixed gas injected from the mixed gas injection port 114c is ignited by an igniter (not shown) to form a flame in the interior space of the furnace.

The second injection part 130 supplies air (secondary air) from the radially outer side to the flame formed by the first injection part 110 .

In this embodiment, the second injection section 130 has a main flow path 132, branch flow paths 134a and 134b, a second oxidant supply pipe 136, and second injection ports 138a and 138b. The main channel 132 is a channel formed in the burner body block 132a and the refractory burner head 132b. The main flow path 132 has a cylindrical shape. The main flow path 132 is arranged coaxially with the main body 114a of the first oxidizing gas injection nozzle 114 so as to surround the main body 114a. The furnace wall 10 side of the main flow path 132 (right side in FIG. 1, hereinafter referred to as "tip") is branched into branch flow paths 134a and 134b. The branch channels 134a and 134b are channels formed in the refractory burner head 132b. The branch flow paths 134 a and 134 b are cylindrical with a diameter smaller than that of the main flow path 132 .

A second oxidant supply pipe 136 is connected to the rear portion of the main flow path 132 (the opposite side of the main flow path 132 to the furnace wall 10 side (the left side in FIG. 1, hereinafter referred to as the "rear end")). The rear end of the main flow path 132 is positioned closer to the furnace wall 10 than the rear end of the main body 114 a of the first oxidizing gas injection nozzle 114 .

In addition, second injection ports 138a and 138b, which are openings, are formed at the ends of the branch flow paths 134a and 134b. The second injection ports 138a, 138b face the interior space of the furnace. The second injection ports 138a and 138b are provided separately from the mixed gas injection port 114c in the radial direction of the mixed gas injection port 114c. The distance between the second injection ports 138a, 138b and the fuel injection port 112c is greater than the radial distance between the inner wall surface of the mixed gas injection port 114c and the fuel injection port 112c.

The second injection ports 138 a and 138 b are provided substantially on the same plane as the mixed gas injection port 114 c of the first injection section 110 . That is, the axial positions of the tips of the branch flow paths 134 a and 134 b substantially match the axial positions of the mixed gas injection port 114 c of the first injection section 110 .

FIG. 2 is a view of the mixed gas injection port 114c of the first injection section 110 and the second injection ports 138a and 138b of the second injection section 130 as viewed from the interior space side of the furnace. As shown in FIG. 2, the center of the mixed gas injection port 114c of the first injection portion 110 and the center of the second injection port 138a of the second injection portion 130 are separated by a distance Ln. Similarly, the center of the mixed gas injection port 114c of the first injection portion 110 and the center of the second injection port 138b of the second injection portion 130 are separated by a distance Ln. The distance Ln is 1.85 times or more and less than 6.0 times the diameter D (diameter) of the mixed gas injection port 114c.

Returning to FIG. 1 , the second supply section 140 supplies air to the second injection section 130 . In this embodiment, the second supply section 140 includes an oxidant supply system 142 . Air is supplied from the oxidant supply system 142 into the main flow path 132 via the second oxidant supply pipe 136 . The air supplied into the main flow path 132 flows through the space inside the main flow path 132 . Then, the air is guided from the main flow path 132 to the branch flow paths 134a, 134b and injected into the interior space of the furnace from the second injection ports 138a, 138b.

[Ratio of Air Amounts of First Supply Portion 120 and Second Supply Portion 140]
Next, the amount of air supplied to the first injection unit 110 (first oxidizing gas injection nozzle 114) by the first supply unit 120 and the amount of air supplied to the second injection unit 130 by the second supply unit 140 I will explain the relationship with

The first supply unit 120 and the second supply unit 140 collectively supply the target air amount of air. The target air amount is a predetermined air amount equal to or greater than the theoretical air amount with respect to the fuel gas supplied by the first supply unit 120 to the first injection unit 110 (fuel injection nozzle 112). The theoretical amount of air is the minimum amount of air required for complete combustion of the fuel gas. The target air amount is, for example, 1.1 to 1.2 times the theoretical air amount.

FIG. 3 is a diagram illustrating the relationship between the ratio of air supplied by the first supply unit 120 and the amount of NOx (nitrogen oxides) contained in the exhaust gas. In FIG. 3, the horizontal axis indicates the ratio of the air supplied by the first supply section 120 to the target air amount. In FIG. 3, the vertical axis indicates the amount of NOx contained in the exhaust gas discharged from the flue (chimney) of the furnace. The NOx amount is the NOx amount contained in the exhaust gas when the first supply unit 120 supplies the target air amount, that is, when the second supply unit 140 (the second injection unit 130) is not provided. 1.00.

As shown in FIG. 3, when the ratio of the air supplied by the first supply unit 120 is 1/2 (the ratio of the air supplied by the second supply unit 140 is also 1/2) or less, the ratio is large. As the temperature increases, the amount of NOx decreases. When the ratio of the air supplied by the first supply unit 120 is 1/2, the NOx amount is approximately 0.08.

On the other hand, when the ratio of the air supplied by the first supply unit 120 exceeds 1/2, the NOx amount increases as the ratio increases. For example, when the ratio of the air supplied by the first supply unit 120 exceeds 4/5 (the ratio of the air supplied by the second supply unit 140 is 1/5), the NOx amount becomes 1.00 or more. .

If less than ⅓ of the target air amount is supplied, the amount of NOx will be 0.25 or less, but the ignitability of the fuel gas will be reduced. On the other hand, if the amount of air that exceeds 2/3 of the target air amount is supplied, the amount of NOx will exceed 0.375.

Therefore, the first supply unit 120 supplies 1/3 to 2/3, preferably 1/2 of the target air amount to the first injection unit 110 (first oxygen-containing gas injection nozzle 114). As a result, the first supply unit 120 can reduce NOx without reducing the ignitability of the fuel gas.

In addition, the fuel gas (ammonia) in the mixed gas injected into the inner space of the furnace from the mixed gas injection port 114c is combusted by the primary air by supplying the primary air less than the target air amount from the first supply unit 120. However, unburned ammonia remains in the interior space of the furnace. Therefore, in the inner space of the furnace, NOx generated by ammonia burned with primary air can be reduced (denitrified) with unburned ammonia. Therefore, the burner 100 can reduce NOx in the exhaust gas generated in the interior space of the furnace.

Then, the second supply unit 140 supplies the second injection unit 130 with the difference between the amount of air supplied to the first injection unit 110 and the target air amount. Thereby, the burner 100 can completely burn the unburned fuel gas with the secondary air.

[Gas flow velocity ratio of first injection unit 110 and second injection unit 130]
Next, the relationship between the flow velocity of the mixed gas jetted from the mixed gas jetting port 114c and the flow velocity of the air jetted from the second jetting ports 138a and 138b will be described.

FIG. 4 shows the relationship between the flow velocity ratio of the mixed gas jetted from the mixed gas jetting port 114c and the flow velocity of the air jetted from the second jetting ports 138a and 138b, and the amount of NOx contained in the exhaust gas. It is a figure explaining. In FIG. 4, the horizontal axis represents the flow velocity ratio a/b between the flow velocity a of the mixed gas jetted from the mixed gas jetting port 114c and the flow velocity b of the air jetted from the second jetting ports 138a and 138b. In FIG. 4, the vertical axis indicates the amount of NOx contained in the exhaust gas discharged from the flue (chimney) of the furnace. The NOx amount is the NOx amount contained in the exhaust gas when the first supply unit 120 supplies the target air amount, that is, when the second supply unit 140 (the second injection unit 130) is not provided. 1.00.

As shown in FIG. 4, the larger the flow velocity ratio a/b, that is, the lower the flow velocity b of the air jetted from the second injection ports 138a and 138b, the lower the NOx amount. For example, when the flow velocity ratio a/b is 0.05, the NOx amount is approximately 0.16. Even if the flow velocity a and the flow velocity b are changed, the NOx amount decreases as the flow velocity ratio a/b increases.

Therefore, the diameters of the mixed gas injection port 114c of the first injection portion 110 and the second injection ports 138a and 138b of the second injection portion 130 are designed so that the flow velocity ratio a/b is 0.05 or more. As a result, the flow velocity ratio a/b between the flow velocity a of the mixed gas injected from the mixed gas injection port 114c and the flow velocity b of the air injected from the second injection ports 138a and 138b becomes 0.05 or more.

[Distance Ln between first injection part 110 and second injection part 130]
Next, the distance Ln between the first injection portion 110 and the second injection portion 130 will be described. As described above, the distance Ln between the center of the mixed gas injection port 114c of the first injection portion 110 and the center of the second injection port 138a of the second injection portion 130 is the diameter D of the mixed gas injection port 114c. It is 1.85 times or more and less than 6.0 times. Further, the distance Ln between the center of the mixed gas injection port 114c of the first injection portion 110 and the center of the second injection port 138b of the second injection portion 130 is 1.85 of the diameter D of the mixed gas injection port 114c. It is more than twice and less than 6.0 times.

FIG. 5 is a diagram showing the relationship between the distance Ln between the first injection portion 110 and the second injection portion 130 and the diameter D of the mixed gas injection port 114c, and the relationship between the concentration of NOx in the exhaust gas. . In FIG. 5, the vertical axis indicates the converted NOx concentration [ppm], and the horizontal axis indicates the co-firing ratio ENH ₃ [%]. The converted NOx concentration is a value calculated using the following formula (1).
Converted NOx concentration = Measured NOx concentration x (21-converted _O2 concentration)/(21-measured _O2 concentration) Equation (1)
In the present embodiment, the converted NOx concentration was calculated with the converted O ₂ concentration set to 11.

Further, the co-firing rate _ENH3 indicates the co-firing rate [%] of ammonia and city gas based on Lower Heating Value (LHV). Note that when the co-firing ratio ENH ₃ is 100%, the fuel gas contains only ammonia. When the co-firing ratio ENH ₃ is 0%, the fuel gas contains only city gas. Further, when the co-firing ratio ENH ₃ is more than 0% and less than 100%, the fuel gas contains ammonia and city gas. City gas is city gas 13A, for example.

Further, in FIG. 5, the solid line indicates the case where distance Ln/aperture D=1.84. In FIG. 5, the dashed line indicates the case where distance Ln/aperture D=3.68. In FIG. 5, the dashed-dotted line indicates the case where distance Ln/aperture D=5.51.

As shown in FIG. 5, when the mixed firing ratio ENH ₃ is less than 80%, the distance Ln/diameter D = 3.68 is higher than the distance Ln/diameter D = 1.84. Low NOx. Also, when the co-firing ratio ENH ₃ is less than 80%, the converted NOx is lower when the distance Ln/aperture D=5.51 than when the distance Ln/aperture D=3.68. That is, the larger the distance Ln/diameter D, the lower the converted NOx.

Further, when the mixed combustion ratio ENH ₃ is 80% or more, the converted NOx is lower when the distance Ln/aperture D=5.51 than when the distance Ln/aperture D=1.84. Further, when the mixed combustion ratio ENH ₃ is 80% or more, the converted NOx is lower when the distance Ln/aperture D=3.68 than when the distance Ln/aperture D=5.51.

Therefore, by setting the distance Ln to 1.85 times or more the diameter D, it is possible to reduce NOx in the exhaust gas.

On the other hand, if the distance Ln is 6.0 times or more the diameter D, the exhaust gas will contain unburned ammonia. Therefore, by setting the distance Ln to be less than 6.0 times the diameter D, it is possible to avoid the situation in which unburned ammonia is generated.

That is, by setting the distance Ln to 1.85 times or more and less than 6.0 times the diameter D, the NOx concentration in the exhaust gas is reduced and the situation in which unburned ammonia is contained in the exhaust gas is avoided. can do.

As described above, the burner 100 according to this embodiment can reduce NOx in the exhaust gas. As a result, the burner 100 can burn the ammonia-containing fuel gas below the NOx emission standard value of the Air Pollution Control Law.

Further, the burner 100 can be obtained by simply attaching the first supply section 120, the second injection section 130, and the second supply section 140 to an existing plate flame-stabilizing burner for hydrocarbon fuel. Therefore, it is possible to use an existing plate flame-stabilizing burner for hydrocarbon fuel to burn a fuel gas containing ammonia with low NOx.

Moreover, the burner 100 can improve the combustibility of ammonia, which has a slow combustion rate, and can improve the thermal efficiency of the furnace.

Although the preferred embodiments of the present invention have been described above with reference to the accompanying drawings, it goes without saying that the present invention is not limited to such embodiments. It is obvious that a person skilled in the art can conceive of various modifications or modifications within the scope described in the claims, and these also belong to the technical scope of the present invention. Understood.

For example, in the above-described embodiments, air was taken as an example of the oxidant gas. However, the oxidant gas only needs to be able to burn the fuel gas. The oxidant gas may be air, oxygen-enriched air, or oxygen, for example. When the oxidizing gas is other than air, the theoretical air amount is the theoretical oxidizing agent amount, and the target air amount is the target oxidizing agent amount. The theoretical oxidant amount is the minimum amount of oxidant gas required for complete combustion of the fuel gas. Also, the target oxidant amount is a predetermined oxidant gas amount equal to or greater than the theoretical oxidant amount, and is, for example, 1.1 to 1.2 times the theoretical oxidant amount.

Further, in the above-described embodiment, the case where the main body 112a of the fuel injection nozzle 112 and the main body 114a of the first oxidant gas injection nozzle 114 are tubular bodies was taken as an example. However, the main body 112a of the fuel injection nozzle 112 and the main body 114a of the first oxidant gas injection nozzle 114 may be channels formed in the burner body block 132a and the refractory burner head 132b.

Similarly, in the above embodiment, the main channel 132 is the channel formed in the burner body block 132a and the refractory burner head 132b, and the branch channels 134a and 134b are formed in the refractory burner head 132b. As an example, the case of the flow path where the However, the main channel 132 and the branch channels 134a, 134b may be tubular bodies.

Further, in the above embodiment, the case where the second injection ports 138a and 138b of the second injection portion 130 and the mixed gas injection port 114c of the first injection portion 110 are provided on substantially the same plane was taken as an example. However, the second injection ports 138 a and 138 b of the second injection portion 130 may not be provided on substantially the same plane as the mixed gas injection port 114 c of the first injection portion 110 . For example, the second injection ports 138a, 138b of the second injection part 130 may be provided toward the flame.

Further, in the above-described embodiment, the case where the fuel injection port 112c of the fuel injection nozzle 112 is provided so as to be positioned inside the main body 114a of the first oxygen-containing gas injection nozzle 114 was taken as an example. However, the fuel injection port 112c of the fuel injection nozzle 112 may be provided on substantially the same plane as the mixed gas injection port 114c of the first oxidizing gas injection nozzle 114, or the main body of the first oxidizing gas injection nozzle 114 may be provided. It may protrude from the tip of 114a. In this case, primary air is injected from the mixed gas injection port 114c (oxidant injection port) to generate a mixed gas in the interior space of the furnace. Further, when the mixed gas injection port 114c injects the primary air, the fuel injection port 112c and the mixed gas injection port 114c may each be provided in plurality, or one fuel injection port 112c may be provided and the mixed gas injection port A plurality of 114c may be provided so as to surround the fuel injection port 112c. In this case, the flow velocity a of the fuel gas injected from the fuel injection port 112c, the flow velocity a of the primary air injected from the mixed gas injection port 114c, and the secondary air injected from the second injection ports 138a and 138b The flow velocity ratio a/b to the flow velocity b is preferably 0.05 or more.

Further, in the above embodiment, the case where the first injection section 110 includes the fuel injection nozzle 112 and the first oxygen-containing gas injection nozzle 114 is taken as an example. However, the first injection part 110 may have one nozzle through which the mixed gas of the fuel gas and the oxidant gas flows. In this case, one or more first injection ports for injecting the mixed gas are provided.

Moreover, in the above-described embodiment, the case where the second injection portion 130 includes the second injection ports 138a and 138b is taken as an example. However, the number of second injection ports provided in the second injection part 130 is not limited. For example, the second injection part 130 may have only one second injection port, or may have three or more. In addition, when the second injection part 130 has three or more second injection ports, it is preferable that the plurality of second injection ports be provided at substantially equal intervals on substantially the same circumference. In addition, since the second injection part 130 has a plurality of second injection ports, the fuel gas can be efficiently burned.

Further, in the above embodiment, the case where the flow velocity ratio a/b is 0.05 or more was taken as an example. However, the first supply unit 120 supplies the fuel gas and the air of ⅓ or more and ⅔ or less of the target oxidizer amount to the first injection unit 110, and the second injection unit 130 supplies the first injection unit 110 The flow velocity ratio a/b may be less than 0.05 by supplying the second injection section 130 with the difference between the amount of air supplied to the second injection section 130 and the target air amount.

Further, in the above embodiment, the first supply unit 120 supplies the fuel gas and the air of ⅓ or more and ⅔ or less of the target oxidizer amount to the first injection unit 110, and the second injection unit 130 supplies The case where the difference between the amount of air supplied to the first injection unit 110 and the target air amount is supplied to the second injection unit 130 is taken as an example. However, as long as the flow velocity ratio a/b is 0.05 or more, there is no limitation on the ratio between the amount of air supplied by the first supply unit 120 and the amount of air supplied by the second injection unit 130 .

Further, in the above embodiment, the case where the first injection part 110 has one first injection port (mixed gas injection port 114c) formed in the furnace wall 10 is taken as an example. However, when the first injection part 110 has a plurality of first injection holes formed in the furnace wall 10, the distance between the center of gravity of the plurality of first injection holes and the center of gravity of one or more second injection holes The distance Ln may be 1.85 times or more and less than 6.0 times the length of the longest imaginary straight line among imaginary straight lines connecting the centers of two first ejection openings in the plurality of first ejection openings.

100 Burner 110 First injection portion 112c Fuel injection port (first injection port)
114c Mixed gas injection port (oxidant injection port, first injection port)
120 First supply section 130 Second injection section 138a Second injection port 140 Second supply section

Claims (7)

a first injection section including one or more first injection ports provided toward the interior space of the furnace;
a second injection part including one or more second injection ports spaced apart from the first injection port and directed toward the interior space of the furnace;
a first supply unit configured to supply fuel gas containing at least ammonia and oxidant gas of ⅓ or more and ⅔ or less of a target oxidant amount equal to or greater than the theoretical oxidant amount for the fuel gas to the first injection unit; ,
a second supply section that supplies the second injection section with the oxidant gas that is the difference between the amount of the oxidant gas that is supplied to the first injection section and the target oxidant amount;
burner with The flow velocity ratio a/b between the flow velocity a of the fuel gas and the oxidant gas injected from the first injection port and the flow velocity b of the oxidant gas injected from the second injection port is 0.05. The burner according to claim 1, wherein: 3. The burner according to claim 1, wherein the first injection port includes a fuel injection port for injecting the fuel gas and an oxidant injection port for injecting the oxidant gas. 3. The burner according to claim 1, wherein said first injection port injects a mixed gas containing said fuel gas and said oxidant gas. a first injection section including one or more first injection ports provided toward the interior space of the furnace;
a second injection part that is separated from the first injection port and includes one or more second injection ports that are provided toward the interior space of the furnace;
a first supply unit that supplies a fuel gas containing at least ammonia and an oxidant gas to the first injection unit;
a second supply unit that supplies the oxidant gas to the second injection unit;
with
The flow velocity ratio a/b between the flow velocity a of the fuel gas and the oxidant gas injected from the first injection port and the flow velocity b of the oxidant gas injected from the second injection port is 0.05. Burner that is over. The first injection part has one of the first injection ports,
6. The distance between the first injection part and the second injection part according to any one of claims 1 to 5, which is 1.85 times or more and less than 6.0 times the diameter of the first injection port. burner. The first injection part has a plurality of the first injection ports,
The distance between the first injection part and the second injection part is the length of the longest imaginary straight line among imaginary straight lines connecting the centers of two of the plurality of first injection holes. 6. The burner according to any one of claims 1 to 5, which is 1.85 times or more and less than 6.0 times.

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