Ammonia gas nozzle and denitration device

Abstract

The invention discloses an ammonia gas nozzle and a denitration device.The ammonia gas nozzle comprises a body and a guide part, the body is provided with a spraying cavity extending in the axial direction of the body, one end of the spraying cavity communicates with a spraying pipe, the other end of the spraying cavity is a spraying opening, the guide part is located on the outer side of the spraying opening, and the front end of the guide part is connected with the body; the orthographic projection of the front end of the guide piece on the first plane is located on the inner side of the jet orifice, at least part of the peripheral edge of the orthographic projection of the tail end of the guide piece on the first plane is located on the outer side of the jet orifice, and the first plane is the plane where the jet orifice is located. The ammonia gas nozzle can spray ammonia gas in a larger range, the mixing ratio of the ammonia gas and flue gas is increased, ammonia escape is reduced, the chemical reaction speed is increased, and then the denitration effect is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of denitration equipment, and in particular to an ammonia nozzle and a denitration device. Background Art

[0002] Most of the ammonia nozzles in the destocking system are made of short tubes to make direct injection nozzles. The nozzle has a simple structure and low manufacturing cost, but the ejected ammonia is sprayed along the axis of the nozzle to form a circular ammonia flow with a diameter of about 150-250mm. The ammonia flow in this shape can only be mixed with a small amount of flue gas. The mixing ratio of flue gas and ammonia near the nozzle is very high, and the mixing ratio of flue gas and ammonia far from the nozzle is low, resulting in unsatisfactory mixing effect. NOX in some flue gas is not mixed with ammonia, and sufficient chemical reaction cannot be carried out, resulting in high NOX in boiler exhaust gas, large ammonia escape NH3 after chemical reaction of flue gas with high mixing ratio, and long-term operation causes blockage of air preheater and large ammonia usage.

[0003] In addition, due to the uneven mixing of flue gas and ammonia and the slow chemical reaction rate, the out-of-stock control cannot be automatically controlled and manual control is forced to be used, which increases the operating cost and safety risks of the unit. Summary of the invention

[0004] The technical problem to be solved by the present invention is that, in view of the defects and shortcomings of the prior art, an ammonia nozzle is proposed, which can spray over a wider range, improve the mixing ratio, reduce ammonia escape, increase the chemical reaction rate, and thus improve the denitrification effect.

[0005] The ammonia nozzle of the embodiment of the present invention includes a body and a guide member, the body has an injection cavity extending along its axial direction, one end of the injection cavity is connected to the nozzle, and the other end is an injection port, the guide member is located outside the injection port and its front end is connected to the body, the orthographic projection of the front end of the guide member on the first plane is located inside the injection port, and at least part of the peripheral edge of the orthographic projection of the tail end of the guide member on the first plane is located outside the injection port, and the first plane is the plane where the injection port is located.

[0006] In the ammonia nozzle of the embodiment of the present invention, the guide member is located on the outside of the injection port and its front end is connected to the body, the orthographic projection of the front end of the guide member on the first plane is located on the inside of the injection port, and at least a part of the outer peripheral edge of the orthographic projection of the tail end of the guide member on the first plane is located on the outside of the injection port, and the first plane is the plane where the injection port is located. Therefore, under the guidance of the guide member, the injection port can perform a wider range of injection, improve the mixing ratio, reduce ammonia escape, increase the chemical reaction rate, and thereby improve the denitrification effect.

[0007] In some embodiments, a connecting surface between a front end of the guide member and a rear end of the guide member is a guide surface, and a cross-sectional area of ​​the guide surface gradually increases in a direction away from the main body.

[0008] In some embodiments, the guide surface is an inwardly concave arc surface.

[0009] In some embodiments, a tangent line of an end of the guide surface away from the body is parallel to the injection port.

[0010] In some embodiments, the orthographic projection of the tail end of the guide surface on the first plane is a circle.

[0011] In some embodiments, the inner wall of the injection port is provided with a connecting rod extending inwardly, and the guide member is connected to the connecting rod.

[0012] In some embodiments, the connecting rods are multiple and are arranged at intervals along the circumference of the injection port, and inner ends of the multiple connecting rods are connected.

[0013] In some embodiments, the orthographic projection of the connection points of the plurality of connecting rods on the first plane coincides with the center of the injection port.

[0014] In some embodiments, the injection chamber includes a connected acceleration section and a flare section, wherein the acceleration section is connected to the nozzle and the cross-sectional area of ​​the acceleration section gradually decreases in the direction away from the nozzle, and the flare section is connected to the injection port and the cross-sectional area of ​​the flare section gradually increases in the direction close to the injection port.

[0015] The denitration device of the embodiment of the present invention includes the ammonia nozzle described in the above embodiment.

[0016] The denitrification device of the embodiment of the present invention adopts the above-mentioned ammonia nozzle, the guide member is located on the outside of the injection port and its front end is connected to the main body, the orthographic projection of the front end of the guide member on the first plane is located on the inside of the injection port, and at least a part of the outer peripheral edge of the orthographic projection of the tail end of the guide member on the first plane is located on the outside of the injection port, and the first plane is the plane where the injection port is located. Therefore, under the guidance of the guide member, the injection port can perform a wider range of injection, improve the mixing ratio, reduce ammonia escape, increase the chemical reaction rate, and thus improve the denitrification effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 Schematic diagram of the structure of an ammonia nozzle according to an embodiment of the present invention.

[0018] Reference numerals:

[0019] Main body 1 , injection chamber 11 , guide member 2 , guide surface 21 . DETAILED DESCRIPTION

[0020] Embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to be used to explain the present invention, but should not be understood as limiting the present invention.

[0021] like Figure 1 As shown, the ammonia nozzle of the embodiment of the present invention includes a body 1 and a guide member 2, the body 1 has an injection chamber 11 extending along its axial direction, one end of the injection chamber 11 is connected to the nozzle, and the other end is an injection port, the guide member 2 is located outside the injection port and its front end is connected to the body 1, the orthographic projection of the front end of the guide member 2 on the first plane is located inside the injection port, and at least part of the outer peripheral edge of the orthographic projection of the tail end of the guide member 2 on the first plane is located outside the injection port, and the first plane is the plane where the injection port is located.

[0022] It can be understood that the ammonia gas ejected from the injection port will flow under the guidance of the guide member 2. Since the outer end of the guide member 2 expands outward and exceeds the range of the injection port, the ammonia gas can be guided to be sprayed over a large range, so that the ammonia gas can be fully mixed with the flue gas in a larger range, thereby improving the mixing ratio, reducing ammonia escape, and increasing the chemical reaction rate, thereby improving the denitrification effect.

[0023] In the ammonia nozzle of the embodiment of the present invention, the guide member 2 is located on the outside of the injection port and its front end is connected to the main body 1, the orthographic projection of the front end of the guide member 2 on the first plane is located on the inside of the injection port, and at least part of the outer peripheral edge of the orthographic projection of the tail end of the guide member 2 on the first plane is located on the outside of the injection port, and the first plane is the plane where the injection port is located. Therefore, under the guidance of the guide member 2, the injection port can perform a wider range of injection, improve the mixing ratio, reduce ammonia escape, increase the chemical reaction rate, and thereby improve the denitration effect.

[0024] In some embodiments, the connecting surface between the front end of the guide member 2 and the rear end of the guide member 2 is a guide surface 21, and the cross-sectional area of ​​the guide surface 21 gradually increases in the direction away from the body 1. Thus, the ammonia gas sprayed from the injection port can gradually expand outward along the guide surface 21, thereby increasing the injection range.

[0025] Optionally, the guide surface 21 is an inwardly concave arc surface, so that the flow of ammonia along the guide member 2 is more stable, and the arc surface structure can change the direction of the airflow, so that the ammonia gas diverges toward the periphery.

[0026] Preferably, the tangent of the end of the guide surface 21 away from the body 1 is parallel to the injection port. In other words, the extension direction of the tail end of the guide surface 21 is parallel to the injection port, and the ammonia can eventually be horizontally sprayed outward along the tail end of the guide surface 21, thereby forming a large-scale spray circle, maximizing the ammonia spray range, and effectively expanding the amount of ammonia sprayed and flue gas mixed, ensuring the mixing ratio of flue gas and ammonia, and increasing the speed of the desulfurization chemical reaction. In addition, after the guide surface 21 changes the direction of ammonia spray, ammonia is no longer sprayed forward and backward, thereby solving the problem that the traditional ammonia nozzle has a high mixing ratio of flue gas with the nozzle accessories, a low mixing ratio with the flue gas far away from the nozzle, and a large difference in the mixing ratio of far and near flue gas.

[0027] Preferably, the orthographic projection of the tail end of the guide surface 21 on the first plane is circular. That is, if the tail end of the guide member 2 is circular, the ammonia gas can be sprayed outward along the tail end of the guide member 2 to form an annular spray circle, with a large spray range and a large amount of ammonia gas mixed with flue gas. Specifically, Figure 1 As shown, the guide member 2 is trumpet-shaped, and the front tip is connected to the body 1 as a connecting end. The outwardly expanded arc-shaped guide surface 21 can guide the flow of ammonia and eventually spray it horizontally outward from the edge position, forming a large-scale annular spray circle.

[0028] In some embodiments, the inner wall of the injection port is provided with a connecting rod extending inwardly, and the guide member 2 is connected to the connecting rod. That is, the inner wall of the body 1 is provided with a connecting rod, the connecting rod extends inwardly, and the end portion is connected to the guide member 2 as a fulcrum.

[0029] Furthermore, the connecting rods are arranged at intervals along the circumference of the injection port, and the inner ends of the multiple connecting rods are connected. In other words, the inner ends of the multiple connecting rods are connected together to form a mounting fulcrum, and there are gaps between the connecting rods, which will not affect the spraying of ammonia gas. The multiple connecting rods can provide a more stable support capacity to ensure the stability of the installation of the guide member 2.

[0030] Preferably, the orthographic projection of the connection points of the plurality of connecting rods on the first plane coincides with the center of the injection port. Thus, the guide member 2 is installed in the middle of the injection port, so that the ammonia gas can diffuse outward evenly.

[0031] In some embodiments, the injection chamber 11 includes a connected acceleration section and a flaring section, the acceleration section is connected to the nozzle and the cross-sectional area of ​​the acceleration section gradually decreases in the direction away from the nozzle, and the flaring section is connected to the injection port and the cross-sectional area of ​​the flaring section gradually increases in the direction close to the injection port. In other words, the injection chamber 11 is designed to first contract and then expand along the injection direction, thereby increasing the ammonia flow rate at the nozzle outlet, improving the ammonia rigidity at the nozzle outlet, and expanding the mixing range of ammonia and flue gas.

[0032] The denitration device according to the embodiment of the present invention includes the ammonia nozzle according to the above embodiment.

[0033] The denitrification device of the embodiment of the present invention adopts the above-mentioned ammonia nozzle, the guide member 2 is located on the outside of the injection port and its front end is connected to the main body 1, the orthographic projection of the front end of the guide member 2 on the first plane is located on the inside of the injection port, and at least part of the peripheral edge of the orthographic projection of the tail end of the guide member 2 on the first plane is located on the outside of the injection port, and the first plane is the plane where the injection port is located. Therefore, under the guidance of the guide member 2, the injection port can perform a wider range of injection, improve the mixing ratio, reduce ammonia escape, increase the chemical reaction rate, and thus improve the denitrification effect.

[0034] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0035] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0036] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0037] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0038] In the present invention, the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" etc. mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the described specific features, structures, materials or characteristics may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0039] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. An ammonia nozzle, characterized in that: The invention comprises a body and a guide member, wherein the body has an injection cavity extending along its axial direction, one end of the injection cavity is connected to a nozzle, and the other end is an injection port, the guide member is located outside the injection port and a front end thereof is connected to the body, an orthographic projection of the front end of the guide member on a first plane is located inside the injection port, at least a portion of an outer peripheral edge of an orthographic projection of the tail end of the guide member on the first plane is located outside the injection port, and the first plane is a plane where the injection port is located.

2. The ammonia nozzle according to claim 1, characterized in that: A connecting surface between the front end of the guide member and the rear end of the guide member is a guide surface, and a cross-sectional area of ​​the guide surface gradually increases in a direction away from the main body.

3. The ammonia nozzle according to claim 2, characterized in that: The guide surface is an inwardly concave arc surface.

4. The ammonia nozzle according to claim 3, characterized in that: A tangent line of an end of the guide surface away from the body is parallel to the injection port.

5. The ammonia nozzle according to claim 2, characterized in that: The orthographic projection of the tail end of the guide surface on the first plane is a circle.

6. The ammonia nozzle according to claim 1, characterized in that: The inner wall of the injection port is provided with a connecting rod extending inwardly, and the guide member is connected to the connecting rod.

7. The ammonia nozzle according to claim 6, characterized in that: The connecting rods are multiple and are arranged at intervals along the circumference of the injection port, and the inner ends of the multiple connecting rods are connected.

8. The ammonia nozzle according to claim 7, characterized in that: The orthographic projection of the connection points of the plurality of connecting rods on the first plane coincides with the center of the injection port.

9. The ammonia nozzle according to claim 1, characterized in that: The injection chamber includes a connected acceleration section and a flaring section, wherein the acceleration section is connected to the nozzle and the cross-sectional area of ​​the acceleration section gradually decreases in the direction away from the nozzle, and the flaring section is connected to the injection port and the cross-sectional area of ​​the flaring section gradually increases in the direction close to the injection port.

10. A denitration device, characterized in that: Comprising the ammonia nozzle according to any one of claims 1-9.

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