Flow guiding mechanism and selective catalytic reduction equipment

Abstract

The present invention provides a flow guiding mechanism and a selective catalytic reduction device, relating to the technical field of nitrogen oxide removal. The flow guiding mechanism provided by the present invention includes: a first flue pipe, a reactor, and a rectifying plate; the first flue pipe is connected to the reactor, and the first flue pipe communicates with the reaction chamber of the reactor; the rectifying plate is installed in the reactor; from one end close to the first flue pipe to the end far from the first flue pipe, the rectifying plate inclines in a direction away from the reaction chamber. The flow guiding mechanism provided by the present invention improves the flue gas uniformity and improves the incident angle, thereby ensuring the safe, efficient, and stable operation of the catalyst.

Description

Technical Field

[0001] The present invention relates to the technical field of nitrogen oxide removal, and particularly to a flow guiding mechanism and a selective catalytic reduction device. Background Art

[0002] Selective catalytic reduction (SCR) is the most efficient nitrogen oxide removal technology. During the reduction process, in order to ensure the efficient, safe and stable operation of the catalyst, it is necessary to optimize the flow field of the catalytic reduction system. Although the rectifying grid arranged in a low position can play a role in guiding the flow, there are generally low-speed areas and recirculation areas of flue gas in the area near the front wall, which are likely to cause fly ash deposition and blockage of some catalyst channels, and further cause problems such as too high flow velocity and serious wear in the remaining catalyst channels. Summary of the Invention

[0003] The purpose of the present invention is to provide a flow guiding mechanism and a selective catalytic reduction device, which can improve the uniformity of flue gas and the incident angle.

[0004] In a first aspect, the flow guiding mechanism provided by the present invention includes: a first flue pipe, a reactor and a rectifying plate;

[0005] The first flue pipe is connected to the reactor, and the first flue pipe communicates with the reaction chamber of the reactor;

[0006] The rectifying plate is installed in the reactor;

[0007] From one end close to the first flue pipe to the end far from the first flue pipe, the rectifying plate inclines in a direction away from the reaction chamber.

[0008] Combined with the first aspect, the present invention provides a first possible implementation manner of the first aspect, wherein the extending direction of the first flue pipe is perpendicular to the extending direction of the reaction chamber.

[0009] Combined with the first aspect, the present invention provides a second possible implementation manner of the first aspect, wherein a buffer chamber is formed on the side of the rectifying plate facing away from the reaction chamber, and the buffer chamber communicates with the first flue pipe;

[0010] The side wall of the buffer chamber opposite to the rectifying plate is parallel to the extending direction of the first flue pipe.

[0011] Combined with the first aspect, the present invention provides a third possible implementation manner of the first aspect, wherein the rectifying plate is provided with a plurality of flow guiding holes, the plurality of flow guiding holes are arranged at intervals, and the extending direction of the flow guiding holes is parallel to the extending direction of the reaction chamber.

[0012] In combination with the first aspect, the present invention provides a fourth possible implementation manner of the first aspect, wherein a catalyst layer is filled in the reaction chamber.

[0013] In combination with the first aspect, the present invention provides a fifth possible implementation manner of the first aspect, wherein a second flue gas pipe is connected to the bottom of the reactor, and the second flue gas pipe is in fluid communication with the reaction chamber.

[0014] In combination with the fifth possible implementation manner of the first aspect, the present invention provides a sixth possible implementation manner of the first aspect, wherein a conical pipe is connected between the reactor and the second flue gas pipe;

[0015] From the end connected to the reactor to the end connected to the second flue gas pipe, the radial dimension of the conical pipe decreases.

[0016] In combination with the fifth possible implementation manner of the first aspect, the present invention provides a seventh possible implementation manner of the first aspect, wherein the second flue gas pipe includes an inclined pipe, the inclined pipe is in fluid communication with the reaction chamber, and the extending direction of the inclined pipe has an included angle with the extending direction of the reaction chamber.

[0017] In combination with the seventh possible implementation manner of the first aspect, the present invention provides an eighth possible implementation manner of the first aspect, wherein the second flue gas pipe further includes an exhaust pipe, the exhaust pipe is communicated with the inclined pipe, and the exhaust pipe has an included angle with the inclined pipe.

[0018] In the second aspect, the selective catalytic reduction device provided by the present invention is provided with the flow guiding mechanism provided by the first aspect.

[0019] The embodiments of the present invention bring the following beneficial effects: The first flue gas pipe is connected to the reactor, and the first flue gas pipe is communicated with the reaction chamber of the reactor. The flow rectifying plate is installed in the reactor. From the end close to the first flue gas pipe to the end far from the first flue gas pipe, the flow rectifying plate inclines in the direction away from the reaction chamber. The flue gas flows from the first flue gas pipe to the flow rectifying plate, and the flue gas passing through the flow rectifying plate is evenly distributed in the reaction chamber, improving the uniformity of the flue gas and improving the incident angle, and further ensuring the safe, efficient and stable operation of the catalyst.

[0020] In order to make the above objects, features and advantages of the present invention more obvious and understandable, the following specific preferred embodiments are given below in conjunction with the accompanying drawings for detailed description. Description of the Drawings

[0021] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the related art, the following will briefly introduce the drawings required for use in the description of the specific embodiments or the related art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0022] Figure 1 Schematic diagram of the flow guiding mechanism provided by an embodiment of the present invention;

[0023] Figure 2 Schematic diagram of the first flue pipe, reactor and rectifying plate of the flow guiding mechanism provided by an embodiment of the present invention;

[0024] Figure 3 Flow streamline diagram of the flue gas of the flow guiding mechanism provided by an embodiment of the present invention;

[0025] Figure 4 Static pressure distribution cloud diagram of the flue gas of the flow guiding mechanism provided by an embodiment of the present invention.

[0026] Icon: 001 - First flue pipe; 002 - Reactor; 201 - Reaction chamber; 202 - Buffer chamber; 003 - Rectifying plate; 301 - Flow guiding hole; 004 - Second flue pipe; 401 - Inclined pipe; 402 - Exhaust pipe; 005 - Conical pipe. Specific embodiments

[0027] The following will clearly and completely describe the technical solutions of the present invention in conjunction with the drawings. Obviously, the described embodiments are some embodiments of the present invention, rather than all embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

[0028] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first", "second", "third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. Physical quantities in the formulas, unless otherwise separately marked, should be understood as the basic quantities of the basic units of the International System of Units, or the derived quantities derived from the basic quantities through mathematical operations such as multiplication, division, differentiation or integration.

[0029] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection", and "coupling" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0030] Embodiment 1

[0031] As Figure 1 and Figure 2 shown, the diversion mechanism provided by the embodiment of the present invention includes: a first flue pipe 001, a reactor 002, and a rectifying plate 003; the first flue pipe 001 is connected to the reactor 002, and the first flue pipe 001 communicates with the reaction chamber 201 of the reactor 002; the rectifying plate 003 is installed in the reactor 002; from one end close to the first flue pipe 001 to the end far from the first flue pipe 001, the rectifying plate 003 is inclined in a direction away from the reaction chamber 201.

[0032] Specifically, the first flue pipe 001 serves as the flue gas inlet pipe. The flue gas flows through the first flue pipe 001 to the rectifying plate 003. The flue gas can be dispersed along the surface of the rectifying plate 003, and the flue gas passes through the rectifying plate 003 and is evenly dispersed into the reaction chamber 201 of the reactor 002.

[0033] As Figure 2 , Figure 3 and Figure 4 shown, the flue gas is evenly distributed along the inclined rectifying plate 003. Referring to Figure 3 the streamline diagram of the flue gas, it is discharged into the reaction chamber 201 through the rectifying plate 003, so as to ensure that the flue gas flows evenly along the reaction chamber 201. Referring to Figure 4 the static pressure distribution of the flue gas in

[0034] As Figure 1 and Figure 2 shown, in the embodiment of the present invention, the extending direction of the first flue pipe 001 is perpendicular to the extending direction of the reaction chamber 201.

[0035] Specifically, the flue gas flows through the first flue pipe 001 to the rectifying plate 003, and the flue gas passing through the rectifying plate 003 flows along the reaction chamber 201. During the process of the flue gas passing through the rectifying plate 003, the flue gas turns 90 degrees from the first flue pipe 001 and enters the reaction chamber 201.

[0036] Further, a buffer cavity 202 is formed on the side of the rectifying plate 003 facing away from the reaction chamber 201. The buffer cavity 202 communicates with the first flue pipe 001. The side wall of the buffer cavity 202 opposite to the rectifying plate 003 is parallel to the extending direction of the first flue pipe 001.

[0037] Specifically, the flue gas flowing along the first flue pipe 001 enters the buffer cavity 202. The side wall of the buffer cavity 202 opposite to the rectifying plate 003 is a plane, and this plane is parallel to the extending direction of the first flue pipe 001. The flue gas entering the buffer cavity 202 from the first flue pipe 001 flows along the side wall of the buffer cavity 202 opposite to the rectifying plate 003, so that the flue gas can be evenly distributed along the rectifying plate 003.

[0038] Further, the rectifying plate 003 is provided with a plurality of diversion holes 301. The plurality of diversion holes 301 are arranged at intervals, and the extending direction of the diversion holes 301 is parallel to the extending direction of the reaction chamber 201.

[0039] Specifically, the flue gas entering the buffer cavity 202 is evenly distributed along the rectifying plate 003. The flue gas passes through the plurality of diversion holes 301 and enters the reaction chamber 201, and flows along the reaction chamber 201. Through the guiding of the plurality of diversion holes 301 to the flue gas, the inclination of the flue gas streamline can be avoided, so that the flowing direction of the flue gas is perpendicular to the first layer of catalyst in the reaction chamber 201. Through simulation tests, by using the diversion mechanism provided in this embodiment, the deviation angle of the flowing direction of the flue gas in the reaction chamber 201 is less than 3.23 degrees.

[0040] Further, a catalyst layer is filled in the reaction chamber 201.

[0041] Specifically, a plurality of catalyst layers are provided in the reaction chamber 201, and the catalyst layers are perpendicular to the flowing direction of the flue gas in the reaction chamber 201. The flue gas in the reaction chamber 201 is evenly distributed, and the flowing direction of the flue gas has no deflection. Therefore, a large resistance caused by the deflection of the flue gas flow direction can be avoided, and the catalyst surface can be prevented from being blocked by dust or worn.

[0042] As Figure 1 shown, a second flue pipe 004 is connected to the bottom of the reactor 002. The second flue pipe 004 is in fluid communication with the reaction chamber 201.

[0043] During operation, the flue gas flows through the first flue pipe 001 to the rectifying plate 003. The flue gas passing through the rectifying plate 003 is evenly introduced into the reaction chamber 201. The flue gas is subjected to reduction treatment by the catalyst, and the treated gas is discharged through the second flue pipe 004.

[0044] Further, a conical pipe 005 is connected between the reactor 002 and the second flue pipe 004. From the end connected to the reactor 002 to the end connected to the second flue pipe 004, the radial dimension of the conical pipe 005 decreases.

[0045] Specifically, the gas in the reaction chamber 201 flows into the second flue pipe 004 through the conical pipe 005. As the gas flows, the radial dimension of the conical pipe 005 decreases, which hinders the gas from being discharged, thereby prolonging the residence time of the flue gas in the reaction chamber 201, and further enabling the flue gas to be fully reduced.

[0046] Further, the second flue pipe 004 includes an inclined pipe 401. The inclined pipe 401 is in fluid communication with the reaction chamber 201, and the extension direction of the inclined pipe 401 forms an angle with the extension direction of the reaction chamber 201.

[0047] Specifically, one end of the inclined pipe 401 is connected to the conical pipe 005. The extension direction of the inclined pipe 401 forms an angle with the axis of the conical pipe 005. The gas discharged through the conical pipe 005 enters the inclined pipe 401, and the gas flow direction changes, thereby slowing down the gas discharge, and further prolonging the treatment time of the flue gas in the reaction chamber 201, and improving the catalytic reduction quality.

[0048] Further, the second flue pipe 004 further includes an exhaust pipe 402. The exhaust pipe 402 is in communication with the inclined pipe 401, and the exhaust pipe 402 forms an angle with the inclined pipe 401.

[0049] Specifically, the exhaust pipe 402 is connected to the end of the inclined pipe 401 facing away from the conical pipe 005. The gas flowing into the exhaust pipe 402 through the inclined pipe 401 turns between the inclined pipe 401 and the exhaust pipe 402, thereby slowing down the gas discharge speed and further prolonging the time of the flue gas in the reaction chamber 201.

[0050] Embodiment 2

[0051] As Figure 1 、 Figure 2 、 Figure 3 and Figure 4 shown, the selective catalytic reduction device provided by the embodiment of the present invention is provided with the flow guiding mechanism provided by Embodiment 1.

[0052] Specifically, from the end close to the first flue pipe 001 to the end far from the first flue pipe 001, the rectifying plate 003 is inclined away from the reaction chamber 201, so that the flow-through area of the buffer chamber 202 decreases, thereby avoiding uneven flow distribution caused by a sudden increase in the flow-through area. The flue gas is deflected through the rectifying plate 003 to ensure that the flue gas entering the reaction chamber 201 through the rectifying plate 003 is evenly distributed. Refer to Figure 3 , the streamline of the flue gas in the reaction chamber 201 is not significantly inclined as a whole. The CFD simulation results show that the maximum angle between the flue gas and the first layer of catalyst is 3.23°. Refer to Figure 4, the pressures of each diversion hole 301 leading to the reaction chamber 201 are basically the same, and the relative standard deviation of the inlet flow rate of the catalyst layer in the reaction chamber 201 is 1.9%, improving the uniformity of the flue gas and ensuring the safe, efficient and stable operation of the catalytic reduction reaction.

[0053] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or equivalently replace some or all of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A flow guiding mechanism, characterized in that, Comprising: A first flue gas pipe (001), a reactor (002) and a rectifying plate (003); The first flue gas pipe (001) is connected to the reactor (002), and the first flue gas pipe (001) communicates with the reaction chamber (201) of the reactor (002); The rectifying plate (003) is installed inside the reactor (002); From one end close to the first flue gas pipe (001) to the end far from the first flue gas pipe (001), the rectifying plate (003) inclines in a direction away from the reaction chamber (201); The extending direction of the first flue gas pipe (001) is perpendicular to the extending direction of the reaction chamber (201); A buffer chamber (202) is formed on the side of the rectifying plate (003) away from the reaction chamber (201), and the buffer chamber (202) communicates with the first flue gas pipe (001); the side wall of the buffer chamber (202) opposite to the rectifying plate (003) is parallel to the extending direction of the first flue gas pipe (001); The rectifying plate (003) is provided with a plurality of diversion holes (301), the plurality of diversion holes (301) are arranged at intervals, and the extending direction of the diversion holes (301) is parallel to the extending direction of the reaction chamber (201).

2. The flow guiding mechanism according to claim 1, characterized in that, A catalyst layer is filled in the reaction chamber (201).

3. The flow guiding mechanism according to claim 1, characterized in that, The bottom of the reactor (002) is connected with a second flue gas pipe (004), and the second flue gas pipe (004) is in fluid communication with the reaction chamber (201).

4. The flow guiding mechanism according to claim 3, characterized in that, A conical pipe (005) is connected between the reactor (002) and the second flue gas pipe (004); From the end connected to the reactor (002) to the end connected to the second flue gas pipe (004), the radial dimension of the conical pipe (005) decreases.

5. The flow guiding mechanism according to claim 3, characterized in that, The second flue gas pipe (004) includes an inclined pipe (401), the inclined pipe (401) is in fluid communication with the reaction chamber (201), and the extending direction of the inclined pipe (401) has an included angle with the extending direction of the reaction chamber (201).

6. The flow guiding mechanism according to claim 5, characterized in that, The second flue gas pipe (004) further includes an exhaust pipe (402), the exhaust pipe (402) is communicated with the inclined pipe (401), and the exhaust pipe (402) has an included angle with the inclined pipe (401).

7. A selective catalytic reduction device, characterized in that, The selective catalytic reduction device is provided with the diversion mechanism according to any one of claims 1 - 6.

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