Anti-corrosion ammonia coal mixed combustion direct flow burner

Abstract

The application provides an anti-corrosion ammonia-coal mixed combustion direct-flow spray burner, which comprises a ventilation assembly, a primary air duct and a secondary air duct, the primary air duct and the secondary air duct are connected with the wall surface of a boiler, the primary air duct is provided with a primary air nozzle, the secondary air duct is provided with a secondary air nozzle, the primary air nozzle and the secondary air nozzle are arranged in the boiler, the ventilation assembly is connected with the primary air duct and the secondary air duct, the ventilation assembly is used for ventilating at least one of air or ammonia into the primary air duct and the secondary air duct, and a driving assembly is connected with the primary air nozzle and the secondary air nozzle, so as to drive the primary air nozzle and the secondary air nozzle to move in the direction perpendicular to the wall surface of the boiler. The anti-corrosion ammonia-coal mixed combustion direct-flow spray burner can reduce the corrosion of the boiler water wall and the adjacent nozzle, and improve the safety of the boiler operation.

Description

Technical Field

[0001] This invention relates to the field of burner technology, and more specifically, to a corrosion-resistant ammonia-coal co-firing DC burner. Background Technology

[0002] In related technologies, liquid ammonia can be used as fuel in power plants. Liquid ammonia contains a small amount of water, and when injected into the furnace, it carries a small amount of saturated ammonia water into the furnace. Before evaporation, this water falls onto adjacent nozzles or boiler water-cooled walls, and due to the interaction with electrolytes, it easily causes corrosion of the metal surfaces inside the furnace. Alternatively, when mixed with primary and secondary air, a large amount of ammonia lowers the airflow temperature. The ammonia is absorbed by the water in the airflow to form saturated ammonia gas, which, when injected into the furnace, easily corrodes adjacent burners and boiler water-cooled walls. Summary of the Invention

[0003] This invention aims to at least partially solve one of the technical problems in related technologies. To this end, embodiments of this invention propose a corrosion-resistant ammonia-coal co-firing direct-current burner, which reduces corrosion of the boiler water-cooled walls and other nozzles during ammonia blending, thereby improving the safety of boiler operation.

[0004] The corrosion-resistant ammonia-coal co-firing DC burner of this invention includes:

[0005] A primary air duct and a secondary air duct, both connected to the boiler water-cooled wall, the primary air duct having a primary air nozzle and the secondary air duct having a secondary air nozzle, both the primary and secondary air nozzles being located inside the boiler; a ventilation assembly, connected to both the primary and secondary air ducts, the ventilation assembly being used to introduce at least one of air or ammonia into the primary and secondary air ducts.

[0006] A drive assembly is connected to both the primary air nozzle and the secondary air nozzle to drive the primary air nozzle and the secondary air nozzle to move in a direction orthogonal to the boiler water-cooled wall.

[0007] In this embodiment of the invention, the anti-corrosion ammonia-coal co-firing DC burner, when injecting primary and secondary air into the furnace, uses a drive component to change the relative positions between the primary and secondary air nozzles and between the primary and secondary air nozzles and the boiler furnace wall. This increases the distance between the primary and secondary air nozzles and the distance between them and the boiler furnace wall, thereby reducing the contact between the saturated ammonia gas formed in the furnace and the wall, primary and secondary air nozzles. Consequently, it reduces the corrosive effect of ammonia gas on the boiler water-cooled wall and improves the safety of boiler operation.

[0008] In some embodiments, the ventilation assembly includes a first ventilation channel and a second ventilation channel, wherein the first ventilation channel is used to introduce air and the second ventilation channel is used to introduce ammonia.

[0009] In some embodiments, the drive assembly includes a first drive member and a second drive member, wherein the first drive member is connected to the primary air nozzle and the second drive member is connected to the secondary air nozzle.

[0010] In some embodiments, the distance that the primary air nozzle and the secondary air nozzle move along a direction orthogonal to the boiler water-cooled wall is greater than or equal to 3 cm and less than or equal to 8 cm.

[0011] In some embodiments, the ventilation assembly includes a first ventilation duct and a second ventilation duct, wherein the first ventilation duct is used to introduce air and the second ventilation duct is used to introduce ammonia. In some embodiments, the corrosion-resistant ammonia-coal co-firing DC burner of the present invention further includes a first mixer and a second mixer, wherein the first mixer includes a first air inlet section, a first ammonia inlet section and a first outlet section, the first air inlet section is connected to the first ventilation duct, the first ammonia inlet section is connected to the second ventilation duct, and the first outlet section is connected to the primary air duct;

[0012] The second mixer includes a second air inlet section, a second ammonia inlet section, and a second outlet section. The second air inlet section is connected to the first ventilation duct, the second ammonia inlet section is connected to the second ventilation duct, and the second outlet section is connected to the secondary air duct.

[0013] In some embodiments, the angle between the extending direction of the first air inlet section and the extending direction of the first ammonia inlet section is greater than or equal to 30° and less than or equal to 60°.

[0014] The angle between the extending direction of the second air inlet section and the extending direction of the second ammonia inlet section is greater than or equal to 30° and less than or equal to 60°. In some embodiments, in the direction of gas flow in the mixer, the cross-sectional area of ​​the first ammonia inlet section gradually decreases, and the cross-sectional area of ​​the first outlet section gradually increases;

[0015] In the direction of gas flow in the second mixer, the cross-sectional area of ​​the second ammonia inlet section gradually decreases, and the cross-sectional area of ​​the second outlet section gradually increases. In some embodiments, the extension direction of the second vent, the extension direction of the first mixer, and the extension direction of the primary air duct are all the same;

[0016] The extension directions of the second ventilation duct, the second mixer, and the secondary air duct are all the same.

[0017] In some embodiments, the corrosion-resistant ammonia-coal co-firing DC burner of the present invention further includes a first expansion joint and a second expansion joint, wherein the first expansion joint is connected between the first mixer and the primary air duct;

[0018] The second expansion joint is connected between the second mixer and the secondary air duct.

[0019] In some embodiments, the corrosion-resistant ammonia-coal co-firing DC burner of the present invention further includes a first gate and a second gate. The first gate is connected to the first ventilation channel to block or open the first ventilation channel, and the second gate is connected to the second ventilation channel to block or open the second ventilation channel. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the corrosion-resistant ammonia-coal co-firing DC burner according to an embodiment of the present invention.

[0021] Figure 2 This is a partial structural schematic diagram of the corrosion-resistant ammonia-coal co-firing DC burner according to an embodiment of the present invention.

[0022] Figure 3 This is a schematic diagram of the structure of the corrosion-resistant ammonia-coal co-firing DC burner (when injecting primary air) according to an embodiment of the invention.

[0023] Figure 4 This is a schematic diagram of the structure of the corrosion-resistant ammonia-coal co-firing DC burner (when injecting secondary air) according to an embodiment of the invention.

[0024] Figure 5 This is a schematic diagram of the mixer structure of the corrosion-resistant ammonia-coal co-firing DC burner according to an embodiment of the invention.

[0025] Figure label:

[0026] 100. Boiler water-cooled wall; 200. Conventional secondary air nozzle.

[0027] 2. Ventilation components, 21. First ventilation duct, 22. Second ventilation duct.

[0028] 31. Primary air duct; 32. Secondary air duct.

[0029] 4. Drive components, 41. First drive component, 42. Second drive component,

[0030] 5. First mixer; 51. First air inlet section; 52. First ammonia inlet section; 53. First outlet section.

[0031] 6. First expansion joint,

[0032] 71. First door panel; 72. Second door panel. Detailed Implementation

[0033] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0034] like Figures 1-5 As shown, the corrosion-resistant ammonia-coal co-firing DC burner of this embodiment of the invention includes: a ventilation component 2, a primary air duct 31, a secondary air duct 32, and a drive component 4.

[0035] It should be noted that, as Figure 1 As shown, the structural arrangements on the left side of the primary air duct and the secondary air duct are the same. Therefore, the following embodiments will be described using the structural arrangement on the primary air duct as an example.

[0036] Both primary air duct 31 and secondary air duct 32 are connected to the boiler water-cooled wall. Primary air duct 31 has a primary air nozzle, and secondary air duct 32 has a secondary air nozzle. Both the primary and secondary air nozzles are located inside the boiler. A venting assembly 2 is connected to both primary air duct 31 and secondary air duct 32, and is used to introduce at least one of air or ammonia into the primary air duct 31 and secondary air duct 32. A drive assembly 4 is connected to both the primary and secondary air nozzles to drive them to move in a direction orthogonal to the boiler water-cooled wall 100.

[0037] In some embodiments, the ventilation assembly 2 includes a first ventilation channel 21 and a second ventilation channel 22, wherein the first ventilation channel 21 is used to introduce air and the second ventilation channel 22 is used to introduce ammonia.

[0038] like Figure 1 As shown, the first end of the first ventilation duct 21 is used to introduce air, and the second end of the first ventilation duct 21 is connected to the primary air duct 31. The first end of the second ventilation duct 22 is used to introduce ammonia, and the second end of the second ventilation duct 22 is connected to the primary air duct 31. Both the primary air duct 31 and the secondary air duct 32 are connected to the boiler water-cooled wall 100. The primary air duct 31 has a primary air nozzle, and the secondary air duct 32 has a secondary air nozzle. Both the primary air nozzle and the secondary air nozzle are located inside the combustion duct 1, and the primary air nozzle and the secondary air nozzle are movable along the extension direction orthogonal to the combustion duct 1.

[0039] Specifically, such as Figure 1 As shown, the primary air nozzle (i.e., the right end of the primary air duct 31) is connected to the boiler to allow air, ammonia, or an air-ammonia mixture to be introduced into the boiler. The first end of the first vent 21 is connected to an air pump to allow air to be introduced into the first vent 21. The first end of the second vent 22 is connected to an ammonia generator to allow ammonia to be introduced into the second vent 22.

[0040] It is understandable that the first vent 21 and the second vent 22 can be vented independently, meaning the venting methods include: opening only the first vent 21, opening only the second vent 22, or opening both the first and second vent 21 simultaneously. When both the first and second vent 22 are opened simultaneously, ammonia mixes with air and enters the primary air duct 31. Taking the primary air nozzle as an example, when using the primary air nozzle for mixing, moving the nozzle a certain distance away from the boiler water-cooled wall 100 reduces the contact between the mixed gas and the boiler water-cooled wall 100, thereby reducing the corrosive effect on the boiler water-cooled wall 100.

[0041] Optionally, the corrosion-resistant ammonia-coal co-firing DC burner of the present invention further includes a first gate 71 and a second gate 72. The first gate 71 is connected to the first ventilation channel 21 to block or open the first ventilation channel 21, and the second gate 72 is connected to the second ventilation channel 22 to block or open the second ventilation channel 22.

[0042] Specifically, such as Figure 1 As shown, the first gate 71 is located at the first end of the first channel. The first gate 71 has an open and a closed state. In the open state, the first gate 71 opens to open the first ventilation channel 21, allowing the air pump to draw outside air into the combustion pipeline 1 through the first ventilation channel 21. The second gate 72 is located at the first end of the second channel. The second gate 72 has an open and a closed state. In the open state, the second gate 72 opens to open the second ventilation channel 22, allowing the ammonia production equipment to enter the primary air duct 31 through the second ventilation channel 22.

[0043] Preferably, the first gate 71 and the second gate 72 are controlled by a controller to achieve remote control, and at least one of the first gate 71 and the second gate 72 can be opened or closed to achieve switching between three modes: conventional nozzle, ammonia-coal co-firing nozzle, and pure ammonia gas burning nozzle.

[0044] In other words, when the corrosion-resistant ammonia-coal co-firing direct-current burner of this embodiment injects primary and secondary air into the furnace, it uses a drive component to change the relative positions between the primary and secondary air nozzles and between the primary and secondary air nozzles and the boiler furnace wall. This increases the distance between the primary and secondary air nozzles and the distance between them and the boiler furnace wall, thereby reducing the contact between the saturated ammonia gas formed in the furnace and the wall, primary and secondary air nozzles. This reduces the corrosive effect of ammonia gas on the boiler water-cooled wall and improves the safety of boiler operation. In some embodiments, the corrosion-resistant ammonia-coal co-firing direct-current burner of this embodiment further includes a drive component 4, which is connected to the primary and secondary air nozzles to drive them to move along a direction orthogonal to the extension of the boiler water-cooled wall 100.

[0045] It is understandable that the drive component 4 can be a telescopic motor, a linear module, or other equipment with reciprocating function.

[0046] Preferably, the drive assembly 4 includes a first drive member 41 and a second drive member 42, wherein the first drive member 41 is connected to the primary air nozzle and the second drive member 42 is connected to the secondary air nozzle.

[0047] It is understandable that, such as Figures 1-4 As shown, the first driving component 41 and the second driving component 42 control the primary air nozzle and the secondary air nozzle respectively, so that after the mixed gas enters the primary air duct 31, the mixed gas is then blown with primary air and secondary air in sequence, further ensuring that the mixed gas is fully mixed. In addition, the first driving component 41 and the second driving component 42 drive the primary air nozzle and the secondary air nozzle separately, which also ensures that only one nozzle is located away from the boiler water-cooled wall 100, further avoiding corrosion of adjacent movable nozzles or fixed nozzles (i.e., conventional secondary air nozzles 200).

[0048] Preferably, the distance that the primary air nozzle and the secondary air nozzle move relative to the boiler water-cooled wall 100 is greater than or equal to 3 cm and less than or equal to 8 cm. It is understood that the smaller the distance the primary and secondary air nozzles move relative to the boiler water-cooled wall 100, the greater the impact of the nozzles on adjacent parts of the boiler 100 or other nozzles, resulting in severe corrosion; conversely, the greater the distance the primary and secondary air nozzles move relative to the boiler water-cooled wall 100, the greater the impact on the boiler water-cooled wall 100 opposite to the nozzles, also exacerbating corrosion. Therefore, limiting the movable distance of the primary and secondary air nozzles to 3-8 cm can both reduce corrosion on adjacent parts and protect the nozzles from burn-out.

[0049] In some embodiments, the corrosion-resistant ammonia-coal co-firing DC burner of the present invention further includes a first mixer 5 and a second mixer (not shown in the figure). The first mixer 5 includes a first air inlet section 51, a first ammonia inlet section 52 and a first outlet section 53. The first air inlet section 51 is connected to the first ventilation duct 21, the first ammonia inlet section 52 is connected to the second ventilation duct 22, and the first outlet section 53 is connected to the primary air duct 31. The second mixer includes a second air inlet section, a second ammonia inlet section and a second outlet section. The second air inlet section is connected to the first ventilation duct, the second ammonia inlet section is connected to the second ventilation duct, and the second outlet section is connected to the secondary air duct.

[0050] Specifically, such as Figure 1 and Figure 5 As shown, taking the primary air duct 31 and its connected structures as an example: the first air inlet section 51, the first ammonia inlet section 52, and the first outlet section 53 are connected sequentially from left to right. The first air inlet section 51 is arranged at an angle relative to the first ammonia inlet section 52, so that when the first air inlet section 51 and the first ammonia inlet section 52 are ventilated at the same time, it is convenient for the gas to mix.

[0051] Preferably, the angle between the extension direction of the first air inlet section 51 and the extension direction of the first ammonia inlet section 52 is greater than or equal to 30° and less than or equal to 60°; the angle between the extension direction of the second air inlet section and the extension direction of the second ammonia inlet section is greater than or equal to 30° and less than or equal to 60°.

[0052] like Figure 1 As shown, the angle between the extending direction of the first ammonia inlet section 52 and the extending direction of the first air inlet section 51 is ( Figure 1 The α shown is greater than or equal to 30° and less than or equal to 60°, i.e., 30°≤α≤60°.

[0053] In some embodiments, in the direction of gas flow in the first mixer 5, the cross-sectional area of ​​the first ammonia inlet section 52 gradually decreases, and the cross-sectional area of ​​the first outlet section 53 gradually increases; in the direction of gas flow in the second mixer, the cross-sectional area of ​​the second ammonia inlet section gradually decreases, and the cross-sectional area of ​​the second outlet section gradually increases.

[0054] It is understandable that, such as Figure 1 and Figure 5 As shown, the cross-sectional area of ​​the first air inlet section 51 is the same as the cross-sectional area of ​​the right end of the second inlet section 52. Therefore, when the ammonia gas introduced from the second inlet section 52 enters the first inlet section 51, the flow channel narrows, and the negative pressure generated by the narrow pipe draws the ammonia gas through the pipe of the first ventilation channel 21. This ensures efficient mixing of ammonia gas and air while preventing ammonia gas from overflowing from the first ventilation channel 21.

[0055] Preferably, the extension directions of the second vent 22, the first mixer 5, and the primary air duct 31 are all the same; the extension directions of the second vent 22, the second mixer, and the secondary air duct are all the same.

[0056] In some embodiments, the corrosion-resistant ammonia-coal co-firing DC burner of the present invention further includes a first expansion joint 6 and a second expansion joint, wherein the first expansion joint 6 is connected between the first mixer 5 and the primary air duct 31; and the second expansion joint is connected between the second mixer and the secondary air duct.

[0057] It is understandable that, such as Figure 1 As shown, the left end of the first expansion joint 6 is connected to the first outlet section 53 of the first mixer 5, and the right end of the first expansion joint 6 is connected to the primary air duct 31, so as to compensate for the additional stress caused by the difference in degree and mechanical vibration, and ensure that the primary air duct 31 can move relative to the first ventilation duct 21 and the second ventilation duct 22 in the left and right directions, thereby further improving the safety of operation.

[0058] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0059] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0060] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0061] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0062] In this invention, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0063] Although the above embodiments have been shown and described, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Any changes, modifications, substitutions and variations made to the above embodiments by those skilled in the art are within the protection scope of the present invention.

Claims

1. A corrosion-resistant ammonia-coal co-firing DC burner, characterized in that, include: A primary air duct and a secondary air duct, both connected to the boiler water-cooled wall, the primary air duct having a primary air nozzle and the secondary air duct having a secondary air nozzle, both the primary and secondary air nozzles being located inside the boiler; a ventilation assembly, connected to both the primary and secondary air ducts, the ventilation assembly being used to introduce at least one of air or ammonia into the primary and secondary air ducts. A drive assembly, which is connected to both the primary air nozzle and the secondary air nozzle, for driving the primary air nozzle and the secondary air nozzle to move in a direction orthogonal to the boiler water-cooled wall. The drive assembly includes a first drive component and a second drive component, wherein the first drive component is connected to the primary air nozzle and the second drive component is connected to the secondary air nozzle. The ventilation assembly includes a first ventilation channel and a second ventilation channel, wherein the first ventilation channel is used to introduce air and the second ventilation channel is used to introduce ammonia. It also includes a first mixer and a second mixer. The first mixer includes a first air inlet section, a first ammonia inlet section and a first outlet section. The first air inlet section is connected to the first ventilation duct, the first ammonia inlet section is connected to the second ventilation duct, and the first outlet section is connected to the primary air duct. The second mixer includes a second air inlet section, a second ammonia inlet section, and a second outlet section. The second air inlet section is connected to the first ventilation duct, the second ammonia inlet section is connected to the second ventilation duct, and the second outlet section is connected to the secondary air duct.

2. The corrosion-resistant ammonia-coal co-firing DC burner according to claim 1, characterized in that, The distance that the primary air nozzle and the secondary air nozzle move along a direction orthogonal to the boiler water-cooled wall is greater than or equal to 3 cm and less than or equal to 8 cm.

3. The corrosion-resistant ammonia-coal co-firing DC burner according to claim 1, characterized in that, The angle between the extension direction of the first air inlet section and the extension direction of the first ammonia inlet section is greater than or equal to 30° and less than or equal to 60°. The angle between the extension direction of the second air inlet section and the extension direction of the second ammonia inlet section is greater than or equal to 30° and less than or equal to 60°.

4. The corrosion-resistant ammonia-coal co-firing DC burner according to claim 1, characterized in that, In the direction of gas flow in the first mixer, the cross-sectional area of ​​the first ammonia inlet section gradually decreases, and the cross-sectional area of ​​the first outlet section gradually increases. In the direction of gas flow in the second mixer, the cross-sectional area of ​​the second ammonia inlet section gradually decreases, while the cross-sectional area of ​​the second outlet section gradually increases.

5. The corrosion-resistant ammonia-coal co-firing DC burner according to claim 4, characterized in that, The extension directions of the second ventilation duct, the first mixer, and the primary air duct are all the same. The extension directions of the second ventilation duct, the second mixer, and the secondary air duct are all the same.

6. The corrosion-resistant ammonia-coal co-firing DC burner according to claim 5, characterized in that, It also includes a first expansion joint and a second expansion joint, the first expansion joint being connected between the first mixer and the primary air duct; The second expansion joint is connected between the second mixer and the secondary air duct.

7. The corrosion-resistant ammonia-coal co-firing DC burner according to any one of claims 1-6, characterized in that, It also includes a first gate and a second gate, the first gate being connected to the first ventilation duct to block or open the first ventilation duct, and the second gate being connected to the second ventilation duct to block or open the second ventilation duct.

Images