Burner

Abstract

The present invention relates to a burner capable of burning ammonia together with fuel and suppressing the generation of nitrogen oxides. The burner according to an embodiment may comprise: an ignition pipe accommodating an igniter; multiple ammonia nozzles circumferentially arranged to surround the ignition pipe and spray ammonia; air spray ports arranged to surround the ammonia nozzles and spray primary air; and multiple fuel channels arranged to surround the air spray ports and spray fuel, wherein each of the multiple ammonia nozzles is individually opened or closed so that ammonia is sprayed from the opened ammonia nozzle.

Description

burner

[0001] The present invention relates to a burner capable of burning ammonia together with fuel and suppressing the generation of nitrogen oxides.

[0002] As the severity of climate change and the need for a response have become increasingly prominent, demands for establishing carbon reduction policies and achieving reduction targets are intensifying. For example, most fuels used in various burners are carbon-based fossil fuels such as LNG, LPG, process byproduct gas, oil, and coal; therefore, a solution is emerging to fundamentally and directly reduce carbon emissions during combustion by replacing these carbon-based fuels with carbon-free combustible materials, or carbon-free fuels.

[0003] Ammonia is frequently cited as a representative carbon-free fuel. Interest in ammonia began as a promising intermediate medium for the economical and stable transport of hydrogen; however, because it is a flammable substance with a higher calorific value per unit volume than hydrogen, it can be directly utilized as fuel in burners.

[0004] However, compared to fossil fuels, ammonia requires a higher energy for ignition and has a significantly lower theoretical flame propagation velocity, resulting in poor combustibility; furthermore, the nitrogen components contained in the fuel increase the likelihood of fuel-NOx levels in the flue gas. Therefore, a method is required to burn ammonia stably and effectively.

[0005] (Patent Document 1) KR 2024-0009596 A

[0006] The present invention aims to provide a burner capable of burning ammonia together with fuel and suppressing the generation of nitrogen oxides.

[0007] A burner according to the present invention comprises: an ignition tube that accommodates an igniter; a plurality of ammonia nozzles arranged along a circumferential direction to surround the ignition tube and spray ammonia; an air nozzle arranged to surround the ammonia nozzles and spray primary air; and a plurality of fuel channels arranged to surround the air nozzles and spray fuel, wherein the plurality of ammonia nozzles are each separately opened or closed so that ammonia can be sprayed from the opened ammonia nozzles.

[0008] The burner further includes an ammonia supply pipe surrounding the ignition pipe and a plurality of ammonia nozzles, and the plurality of ammonia nozzles may be supported by a support member provided at one end of the ammonia supply pipe.

[0009] A plurality of the above-mentioned ammonia nozzles may be arranged to be inclined or twisted at a predetermined angle with respect to the axial line of the ammonia supply pipe, thereby changing the ammonia flow into a swirling flow.

[0010] The above air nozzle may be formed by one end of an air supply pipe arranged to surround the ammonia supply pipe and one end of the ammonia supply pipe.

[0011] The above air nozzle may include a plurality of pivot sections arranged at regular intervals in the circumferential direction along the outer surface of the ammonia supply pipe.

[0012] When the distance from the center of the ignition tube to a point corresponding to the average radius of the outer diameter radius and the inner diameter radius of the air injection nozzle is called the first distance (r1) and the distance from the center of the ignition tube to the center of the ammonia nozzle is called the second distance (r2), the ratio of the second distance to the first distance (r2 / r1) may be within the range of 0.1 to 0.6.

[0013] A plurality of the above-mentioned fuel channels may be partitioned by arranging a plurality of partitions between one end of the fuel supply pipe, which is arranged to surround the air supply pipe, and one end of the air supply pipe.

[0014] The burner may further include a burner body formed to surround the fuel supply pipe and constituting an air channel that injects secondary air.

[0015] A plurality of the above-mentioned fuel channels are spaced apart from each other, and a blank is formed between adjacent fuel channels, and inside the fuel supply pipe, the fuel channels and the blank can be alternately arranged along the circumferential direction.

[0016] The blank may form an additional air channel to inject secondary air, and a porous plate may be provided at the downstream opening of the blank.

[0017] The burner further comprises a plurality of valves each connected to the ammonia nozzles, and a control unit for selectively controlling the operation of the valves, wherein the control unit can control the valves to open so that ammonia is sprayed from the desired ammonia nozzles.

[0018] The above control unit can set the mixing rate of ammonia with respect to fuel, and if the mixing rate is less than a predetermined reference mixing rate, control to open only some of the plurality of ammonia nozzles to inject ammonia.

[0019] At least one of the cross-sectional area, number, and arrangement of the plurality of ammonia nozzles can be determined based on the reference mixing rate.

[0020] The above control unit can control the opening of only half of the plurality of ammonia nozzles alternately.

[0021] When the above mixing rate is set to be greater than or equal to the reference mixing rate, the control unit can control all of the plurality of ammonia nozzles to open and spray ammonia.

[0022] According to an embodiment of the present invention, the effect of reducing the emission of nitrogen oxides during the co-firing of ammonia in a burner is obtained.

[0023] FIG. 1 is a front view illustrating a burner according to the present invention.

[0024] Figure 2 is a cross-sectional view of Figure 1.

[0025] Figure 3 is a diagram showing a schematic comparison of the flame structure when the number of openings among a plurality of ammonia nozzles is varied according to the mixing ratio in the burner of the present invention.

[0026] Figure 4 is a graph showing the concentration of nitrogen oxides in the flue gas according to the number of open ammonia nozzles at the same co-firing rate lower than the standard.

[0027] FIG. 5 is a schematic diagram showing the pressure or flow rate gradient of ammonia sprayed when adjacent ammonia nozzles are alternately opened and closed.

[0028] For the sake of convenience of explanation, the burner of the present invention is described using an example where it is applied to a rotary kiln, but the application examples of the present invention are not necessarily limited thereto.

[0029] Here, a rotary kiln is a facility that produces processed raw materials according to the purpose of each process by slowly moving and heating (heat treating) raw materials within a long cylindrical rotating furnace lined with refractory material. Among the heating methods, the direct heating type (refractory type), in which the heat source is located inside the rotating furnace, is a common type; to this end, a burner is inserted into the furnace at one end to supply heat to the layer of raw material particles through the combustion of fuel.

[0030] In rotary kilns, appropriate requirements exist regarding flame characteristics, temperature distribution, and the emission of environmental pollutants in combustion exhaust gases, depending on constraints imposed by the narrow and elongated shape of the furnace and the characteristics of the input fuel and raw materials; therefore, the burner structure and operational control required to satisfy these conditions are critical.

[0031] As with other industrial sectors, carbon-based fossil fuels such as LNG, LPG, process by-product gas, oil, and coal are mostly used as fuel for rotary kiln burners; however, as mentioned above, technologies for utilizing ammonia as fuel are being actively researched.

[0032] In terms of ease of application to existing facilities, co-firing technology involving the combustion of ammonia mixed with traditional fossil fuels in a certain proportion is being considered as a priority.

[0033] For example, to promote stable combustion, a partially premixed or nozzle-mixed burner is proposed in which fuel and ammonia are mixed and then supplied inside the burner, or fuel and ammonia are supplied separately and then mixed, and then the mixed fuel reacts with air to form a central flame.

[0034] Combustion technology utilizing ammonia as fuel is expected to gradually progress to co-firing with increasing ammonia mixing ratios or full-firing technology using only 100% ammonia. However, in reality, there are still few demonstration cases where ammonia has been used as fuel in industrial facilities, including rotary kilns, so there is a lack of consideration regarding appropriate application methods for existing facilities.

[0035] Accordingly, the present invention proposes a burner structure with a diffusion flame type that does not have a mixing section within the burner, and a control relationship of the burner that maintains combustion and flow characteristics, so as to implement basic principles for stable combustion such as multi-stage combustion and reduction of nitrogen oxides, as well as to form a long flame through high-speed injection of fuel, ammonia, and air.

[0036] The present invention is described in detail below with reference to exemplary drawings. It should be noted that in assigning reference numerals to the components of each drawing, the same components are given the same reference numeral whenever possible, even if they are shown in different drawings.

[0037] FIG. 1 is a front view illustrating a burner according to the present invention, and FIG. 2 is a cross-sectional view of FIG. 1.

[0038] A burner according to the first embodiment of the present invention may include an ignition tube (10); a plurality of ammonia nozzles (22); an air injection port (32); and a plurality of fuel channels (42).

[0039] The ignition tube (10) can accommodate an igniter (11), such as an electric ignition rod. Such an igniter can discharge at one end and emit a spark from one end of the ignition tube, that is, the downstream end.

[0040] A plurality of ammonia nozzles (22) are arranged along the circumferential direction to surround the ignition tube (10) so as to supply and spray ammonia. The plurality of ammonia nozzles can be accommodated within an ammonia supply tube (20) surrounding the ignition tube (10) and the plurality of ammonia nozzles. Additionally, the plurality of ammonia nozzles can be fixed and supported by a support member (21) provided at one end of the ammonia supply tube.

[0041] Multiple ammonia nozzles (22) need to have structural designs such as position, size and shape, and quantity, and factors such as the velocity or momentum of the injected flow optimally adopted. For example, each ammonia nozzle may have a circular cross-sectional shape, but is not necessarily limited thereto.

[0042] A plurality of ammonia nozzles (22) arranged along the circumferential direction can be used to spray an amount of ammonia corresponding, for example, 20% of the lower heating value. The diameter and number of ammonia nozzles can be determined and designed to form a target flow rate at a level of approximately 0.5 momentum ratio between ammonia and primary air. Here, the ammonia may be gaseous ammonia.

[0043] Optionally, a plurality of ammonia nozzles (22) can form a swirling flow of ammonia. Specifically, a plurality of ammonia nozzles can be fixed and supported on a support member (21) so as to be inclined or twisted at a predetermined angle with respect to the axial line of the ammonia supply pipe (20).

[0044] By arranging multiple ammonia nozzles (22) in an inclined or twisted manner, the ammonia flow sprayed through the ammonia nozzles is changed into a swirling flow, and accordingly, the characteristics of the combustion can be changed.

[0045] The air nozzle (32) is positioned to surround a plurality of ammonia nozzles (22) and can spray air. Specifically, the air nozzle may be formed by one end of an air supply pipe (30) positioned to surround an ammonia supply pipe (20) and one end of an ammonia supply pipe.

[0046] Optionally, a plurality of pivot sections (33) may be disposed in the air nozzle (32). Specifically, the pivot sections may be formed as members in the shape of a roughly twisted plate, and a plurality of pivot sections may be arranged at regular intervals in the circumferential direction along the outer surface of the ammonia supply pipe (20).

[0047] By arranging such a plurality of swirling sections (33) in the air nozzle (32), the air flow injected through the air nozzle is changed into a swirling flow, and accordingly, the supply of air that reacts with fuel can be smoothly carried out.

[0048] The primary air injected from the air nozzle (32) plays a major role in maintaining combustion and forming flame characteristics in the burner, and additionally, by arranging the swirling section (33), it is possible to form a swirling flow to enhance the mixing and reaction of fuel and air.

[0049] In the burner according to the present invention, the air nozzle (32) and the plurality of ammonia nozzles (22) can maintain a predetermined distance from each other to suppress the generation of nitrogen oxides while securing an appropriate combustion temperature.

[0050] For example, it is preferable that the ratio (r2 / r1) of the second distance (r2) from the center of the burner to the center of the ammonia nozzle (22) to the first distance (r1) from the center of the burner (i.e., the center of the ignition tube (10)) to a point corresponding to the average radius of the outer diameter radius and the inner diameter radius of the air nozzle (32) is within the range of about 0.1 to 0.6.

[0051] In other words, the ratio (r2 / r1) of the second distance (r2) to the first distance (r1) may mean that the reference circle (C) of the ammonia nozzles, which can be drawn by connecting the centers of the plurality of ammonia nozzles (22) within the area from the center of the burner to a point corresponding to the average radius of the air nozzle (32), is located away from the center of the burner by a distance corresponding to 10 to 60% of the value of the average radius of the air nozzle.

[0052] If the ratio (r2 / r1) of the second distance (r2) to the first distance (r1) exceeds 0.6, the air nozzle (32) and the ammonia nozzle (22) become too close together, so the effect of separately injecting air and ammonia becomes negligible, and consequently, the generation of nitrogen oxides cannot be suppressed.

[0053] On the other hand, if the ratio (r2 / r1) of the second distance (r2) to the first distance (r1) is less than 0.1, the ignition tube (10) cannot be placed, and a problem arises in that an appropriate combustion temperature cannot be secured.

[0054] A plurality of fuel channels (42) are arranged to surround an air nozzle (32) to inject fuel. Specifically, the plurality of fuel channels may be partitioned by a plurality of partitions (41) arranged between one end of a fuel supply pipe (40) and one end of an air supply pipe, which are arranged to surround an air supply pipe (30).

[0055] Multiple fuel channels (42) may be spaced apart from each other, and a blank (43) may be positioned between adjacent fuel channels. In other words, fuel channels and blanks may be alternately arranged along the circumferential direction inside the fuel supply pipe (40).

[0056] After fuel is introduced into the interior of the fuel supply pipe (40), the fuel can be injected through a plurality of fuel channels (42). Here, the fuel may be a carbon-containing gaseous fossil fuel such as natural gas, but is not necessarily limited thereto.

[0057] The burner according to the present invention may further include a burner body (50) that forms the outer shape of the burner and is formed to surround a fuel supply pipe (40) to form an air channel (52). In other words, the space between the fuel supply pipe and the burner body forms an air channel, and air can be supplied and injected through the air channel.

[0058] Optionally, in the burner according to the present invention, a blank (43) located between adjacent fuel channels (42) may form an additional air channel (54). To this end, a porous plate (55) may be provided at the downstream opening of the blank.

[0059] By means of this porous plate (55), the air flow passing through the additional air channel (54) is changed into multiple branches, and accordingly, the reactivity between the fuel or ammonia and the air is improved so that stable and effective combustion can be achieved.

[0060] As such, the burner according to the present invention is characterized by the fuel and ammonia being injected separately, and combustion air being distributed and injected in multiple stages.

[0061] Fuel is injected through a plurality of fuel channels (42) located radially outward from the air nozzle (32), while ammonia can be injected from a plurality of ammonia nozzles (22) located radially inward from the air nozzle. Therefore, ammonia can be injected over a relatively narrow area, and fuel can be injected over a relatively wide area.

[0062] Combustion air can be divided into primary air injected from the air nozzle (32) as described above, and secondary air injected through the air channel (52) between the fuel supply pipe (40) and the burner body (50) and / or an additional air channel (54) within the fuel supply pipe.

[0063] The distribution ratio of primary air and secondary air can be adjusted according to the channel configuration, fuel type, combustion state, etc. For example, about 10% of the air volume may be injected as primary air from the air injector (32), and the remainder may be injected as secondary air through the air channel (52) and / or additional air channel (54).

[0064] In the burner according to the present invention, at least the ignition tube (10), a plurality of ammonia nozzles (22), air injection ports (32), and a plurality of fuel channels (42) may be arranged concentrically, and their downstream ends may be arranged on a single plane.

[0065] By being arranged in this way, the primary air among the total air volume can be consumed while undergoing a proper combustion reaction in a combustion chamber formed around the downstream end of the burner, together with fuel injected from a plurality of fuel channels (42) located radially outside the primary air and ammonia injected from a plurality of ammonia nozzles (22) located radially inside the primary air.

[0066] In the burner according to the present invention, which adopts a structure of a diffusion flame method and a multi-stage air supply method as described above, fuel and ammonia are each ignited by a flame emitted from an ignition tube (10) by a discharge at the end of an igniter (11), and low-speed air around the burner is drawn in by the high-speed injection flow of fuel, ammonia, and air, so that a flame can be macroscopically formed in the area where mixing and combustion reactions proceed.

[0067] In this flame structure, ammonia is injected separately from the primary air radially, thereby forming a core region within the flame area around the burner that induces a localized ammonia-rich condition to react preferentially with ammonia and a portion of the primary air.

[0068] Through this, ignition of flame-retardant ammonia occurs near the tip of the flame, contributing to overall flame stabilization and simultaneously reducing excessive mixing of combustion air and ammonia, thereby enabling the suppression of nitrogen oxide generation.

[0069] Therefore, in the burner according to the present invention, stable ignition and combustion of ammonia are possible, and an appropriate size of the core region where ammonia is excessively concentrated inside the flame is secured, and as a result, the combustion reaction is slowed down so that the reaction from ammonia to nitrogen oxides can be minimized.

[0070] Furthermore, in the burner according to the present invention, by changing the ammonia flow injected by a plurality of ammonia nozzles (22) into a swirling flow, the characteristics of forming a core region of ammonia and radicals, the characteristics of mixing ambient air and fuel, and the combustion characteristics resulting therefrom can be changed.

[0071] Additionally, the burner according to the present invention may include a plurality of valves (61) connected to each ammonia nozzle (22), and a control unit (60) that selectively controls the operation of the plurality of valves together with the operation of the burner.

[0072] Each ammonia nozzle (22) can be connected to the corresponding ammonia supply line via a valve (61). In this case, an electric valve driven by a motor (not shown) connected to a separate power source under the control of a control unit (60) may be adopted as the valve.

[0073] The opening and closing of this valve (61) is controlled by the internal valve body rotating at a predetermined angle or moving a predetermined distance according to the drive of the motor, thereby controlling the injection of ammonia from each ammonia nozzle (22).

[0074] The control unit (60) can be implemented as various processing devices, such as a microprocessor with a semiconductor chip capable of performing various operations or commands, and can control the overall operation of the burner to, for example, heat raw materials in a rotary kiln.

[0075] For example, the control unit (60) can be merged into or used in combination with a higher control system that controls the rotary kiln.

[0076] Specifically, the control unit (60) can command the operation of the valve (61) according to information input from an operator or a higher-level control system. Under the control of the control unit, the valve can be operated to open so that ammonia is sprayed from the desired ammonia nozzle (22).

[0077] FIG. 3 is a diagram showing a schematic comparison of the flame structure when the number of open ammonia nozzles among a plurality of ammonia nozzles is varied according to the mixing rate in the burner of the present invention, and FIG. 4 is a graph showing the concentration of nitrogen oxides in the flue gas according to the number of open ammonia nozzles at the same mixing rate lower than the standard.

[0078] In addition to the burner structure, it is necessary to improve the method of ammonia injection or the method of operating the ammonia nozzle (22) depending on the amount of ammonia or the mixing rate to be applied.

[0079] For example, in burner structures designed and manufactured based on specific target conditions, changes in injection volume resulting from operating conditions deviating from the standard affect the flow velocity or momentum of the injected gas, and consequently alter combustion and flow patterns. This often leads to consequences such as reduced combustion stability, equipment damage, and increased combustion emissions like nitrogen oxides.

[0080] Moreover, in the case of fuel and ammonia mixing, if a burner designed with a cross-sectional area, number, and arrangement of ammonia nozzles (22) based on a specific mixing rate (hereinafter referred to as the standard mixing rate) injects an amount of ammonia different from the standard through the same ammonia nozzles according to operating conditions, it may be difficult to achieve the originally intended nitrogen oxide reduction effect due to changes in the injection flow rate and the resulting flow pattern.

[0081] Accordingly, the control unit of the burner according to the present invention sets the mixing rate of ammonia with respect to the fuel, and if the set mixing rate is less than a predetermined reference mixing rate, it can control the valve to open so that only some of the plurality of ammonia nozzles (22) are opened to spray ammonia.

[0082] In the burner according to the present invention, the control unit is characterized by controlling the number of activated, i.e., open ammonia nozzles (22) so as to maintain a spray flow rate and momentum that satisfy target conditions for the set ammonia amount or mixing rate to be applied when the set ammonia amount or mixing rate is set.

[0083] Thus, the burner according to the present invention can maintain combustion and flow characteristics and is expected to have a nitrogen oxide reduction effect.

[0084] With reference to FIGS. 3 and 4, the burner according to the present invention can be configured to separate ammonia from fuel and inject it separately through a plurality of ammonia nozzles (22) located inside the primary air.

[0085] In this burner, gaseous fuel is injected from a plurality of fuel channels (42), primary air is injected into the inside through an air nozzle (32), and secondary air is injected outward through an air channel (52) and / or additional air channel (54), and low-speed air may be introduced from the periphery of the burner.

[0086] In the burner according to the present invention, at least one of the cross-sectional area, number, and arrangement of ammonia nozzles (22) can be determined according to the standard mixing rate, and for example, if it is set to operate at a mixing rate of 20% or more, the corresponding amount of ammonia can be sprayed through all of the ammonia nozzles.

[0087] As the combustion reaction of fuel, ammonia, and air proceeds, a high-temperature flame region, which can be represented by OH radicals, is formed as schematically illustrated in FIG. 2(a). At this time, a core region rich in ammonia is formed within the macroscopic flame region, thereby enabling the rapid generation of nitrogen oxides through oxidation reactions in the NH3 and NH2 radical stages and mitigating the intensity of OH radicals in the flame region.

[0088] For example, in a burner in which the cross-sectional area, number, and arrangement of ammonia nozzles (22) are determined to achieve an optimal nitrogen oxide reduction effect based on the standard mixing ratio of ammonia to the fuel, if an amount of ammonia at a mixing ratio of 5% is applied according to the operating conditions, the amount of ammonia injected is also inevitably reduced to 1 / 4.

[0089] When the reduced amount of ammonia is injected equally through six ammonia nozzles (22), the ammonia injection flow rate at each ammonia nozzle is reduced to 25% and the momentum flow per unit area is reduced to 6% compared to the case where the mixing rate is 20%. As a result, the momentum ratio between the injection flow of primary air and ammonia is reduced to 0.03, which is 0.5 when the standard mixing rate is 20%.

[0090] Accordingly, as shown in Fig. 3(b), the injected ammonia does not form a sufficient core area inside the primary air and flows rapidly toward the primary air to burn, which may lead to an increase in the concentration of nitrogen oxides in the flue gas.

[0091] In order to resolve this, that is, to enable the injection flow rate and momentum flow at the ammonia nozzle (22) to be formed above a standard value even when an amount of ammonia with a mixing rate of 5% is injected, the valve (61) can be controlled by the control unit (60) so that only some of the multiple ammonia nozzles are activated, that is, opened, to inject ammonia.

[0092] In this way, as shown in Fig. 3(c), it can be confirmed that the emission of nitrogen oxides is reduced due to actions such as securing a core area relative to the flame area and forming an internal recirculation flow by injection flow.

[0093] In particular, in FIG. 4, for example, when an amount of ammonia at a mixing rate of 5%, which is lower than the standard mixing rate, is injected from all six ammonia nozzles (22), the concentration of nitrogen oxides in the flue gas is 100%, and when the same amount of ammonia at a mixing rate of 5% is injected by two or one ammonia nozzle, it can be seen that the concentration of nitrogen oxides in the flue gas is reduced to a rate of about 94.3% or 92.9%.

[0094] FIG. 5 is a schematic diagram showing the pressure or flow rate gradient of ammonia sprayed when adjacent ammonia nozzles are alternately opened and closed.

[0095] In the burner according to the present invention, if only some of the plurality of ammonia nozzles (22) are controlled to be activated according to the purpose, the mixing of fuel, ammonia, and air can be enhanced around the downstream end of the burner, instead of a structure for forming a swirling flow.

[0096] For example, when it is necessary to ensure combustion stability due to reasons such as the deterioration of fuel and combustion conditions, or when flame shortening and high temperature formation are required, the flow of air and / or ammonia can be changed to a swirling flow to enhance combustion intensity by improving the mixing of fuel, ammonia, and air around the downstream tip of the burner.

[0097] Conversely, if excessive swirling flow unnecessarily shortens the flame length or increases the flame temperature, thereby increasing nitrogen oxide emissions, the intensity of the swirling flow must be reduced.

[0098] However, as mentioned above, in a burner structure designed and manufactured based on specific target conditions, the injection angle of the swirling section (33) or the ammonia nozzle (22) is also fixed as a design value. Therefore, even if a change in combustion characteristics is required through a change in the swirling characteristics of the injection flow during actual operation, it is difficult to find a way to effectively respond to this other than by arbitrarily increasing or decreasing the injection flow rate.

[0099] In order to resolve this, that is, to change the combustion characteristics through a change in the characteristics of the injection flow, only some of the multiple ammonia nozzles (22) can be activated, that is, opened, to inject ammonia.

[0100] Specifically, if only half of the multiple ammonia nozzles (22) arranged at equal intervals along the circumferential direction are alternately activated, that is, opened, then, as shown in FIG. 5, the space corresponding to the deactivated, that is, closed, ammonia nozzles between the activated ammonia nozzles from which ammonia is sprayed will have a relatively low pressure or low flow rate, allowing more air to be introduced.

[0101] In this way, by forming an uneven pressure distribution or uneven flow velocity distribution of the injection flow on the reference circle (C) of the ammonia nozzles (22), it is possible to promote the inflow and mixing of surrounding air including primary air.

[0102] Therefore, even without a separate device to change the spray angle of the swivel section or the ammonia nozzle (22), the flame intensity can be increased and the flame length shortened, thereby ensuring the stability of combustion.

[0103] As described above, according to an embodiment of the present invention, the effect of reducing the emission of nitrogen oxides during the co-firing of ammonia in a burner is obtained.

[0104] The above description is merely an illustrative explanation of the technical concept of the present invention, and those skilled in the art to which the present invention pertains will be able to make various modifications and variations within the scope of the essential characteristics of the present invention.

[0105] Accordingly, the embodiments disclosed in this invention are intended to explain, not limit, the technical concept of the invention, and the scope of the technical concept of the invention is not limited by these embodiments. The scope of protection of this invention shall be interpreted by the claims below, and all technical concepts within an equivalent scope shall be interpreted as being included within the scope of rights of this invention.

[0106] [Explanation of the symbol]

[0107] 10: Ignition tube 11: Ignition device

[0108] 20: Ammonia supply pipe 21: Support part

[0109] 22: Ammonia nozzle 30: Air supply pipe

[0110] 32: Air nozzle 33: Swivel section

[0111] 40: Fuel supply pipe 41: Partition

[0112] 42: Fuel Channel 43: Blank

[0113] 50: Burner body 52: Air channel

[0114] 54: Additional air channel 55: Perforated plate

[0115] 60: Control unit 61: Valve

Claims

1. An ignition tube housing an igniter; A plurality of ammonia nozzles arranged along the circumferential direction to surround the ignition tube and spray ammonia; An air nozzle positioned to surround the ammonia nozzle and spraying primary air; and A plurality of fuel channels arranged to surround the air injection port and injecting fuel Includes, A burner in which ammonia is sprayed from the open ammonia nozzles, wherein a plurality of the above-mentioned ammonia nozzles are each separately opened or closed.

2. In Paragraph 1, It further includes an ammonia supply pipe surrounding the ignition pipe and a plurality of ammonia nozzles, and A plurality of the above-mentioned ammonia nozzles are burners supported by a support member provided at one end of the ammonia supply pipe.

3. In Paragraph 2, A burner in which a plurality of the above-mentioned ammonia nozzles are arranged at a predetermined angle to be inclined or twisted with respect to the axial line of the ammonia supply pipe, thereby changing the ammonia flow into a swirling flow.

4. In Paragraph 2, The above air nozzle is a burner formed by one end of an air supply pipe arranged to surround the ammonia supply pipe and one end of the ammonia supply pipe.

5. In Paragraph 4, The above air nozzle is a burner comprising a plurality of pivot sections arranged at regular intervals in the circumferential direction along the outer surface of the ammonia supply pipe.

6. In Paragraph 4, The distance from the center of the ignition tube to a point corresponding to the average radius of the outer diameter radius and the inner diameter radius of the air nozzle is called the first distance (r1), and When the distance from the center of the ignition tube to the center of the ammonia nozzle is called the second distance (r2), A burner in which the ratio (r2 / r1) of the second distance to the first distance is within the range of 0.1 to 0.

6.

7. In Paragraph 4, A plurality of fuel channels are a burner partitioned by a plurality of partitions arranged between one end of a fuel supply pipe and one end of an air supply pipe, the fuel supply pipe being arranged to surround the air supply pipe.

8. In Paragraph 7, A burner further comprising a burner body formed to surround the fuel supply pipe and constituting an air channel for injecting secondary air.

9. In Paragraph 7, A plurality of the above fuel channels are spaced apart from each other, and a blank is formed between adjacent fuel channels, and A burner in which the fuel channels and the blanks are alternately arranged along the circumferential direction inside the fuel supply pipe.

10. In Paragraph 9, The above blank forms an additional air channel to inject secondary air, and A burner equipped with a perforated plate at the downstream opening of the above blank.

11. In Paragraph 1, A plurality of valves each connected to the ammonia nozzle, and A control unit that selectively controls the operation of the above valve Includes more, The above control unit is a burner that controls the opening of the corresponding valve so that ammonia is sprayed from the desired ammonia nozzle.

12. In Paragraph 11, The above control unit sets the mixing rate of ammonia with respect to fuel, and if the mixing rate is less than a predetermined reference mixing rate, controls the burner to open only some of the plurality of ammonia nozzles to inject ammonia.

13. In Paragraph 12, A plurality of the above-mentioned ammonia nozzles are burners in which at least one of the cross-sectional area, number, and arrangement is determined based on the above-mentioned standard mixing rate.

14. In Paragraph 12, The above control unit controls the burner to alternately open only half of the plurality of ammonia nozzles.

15. In Paragraph 12, When the above mixing rate is set to be greater than or equal to the reference mixing rate, the control unit controls the burner to spray ammonia by opening all of the plurality of ammonia nozzles.

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