Air distribution plate structure for hydrocyanic acid fluidized bed reactor

Abstract

The utility model relates to the field of fluidized bed reactor structural members, in particular to an air distribution plate structure for a hydrocyanic acid fluidized bed reactor, which comprises a distribution plate main body, the plurality of air distribution pipes are distributed in an array manner, are vertically fixed on the distribution plate main body and are used for introducing air; the plurality of flow guide caps are fixed on the distribution plate main body and are arranged above the tops of the air distribution pipes in a one-to-one correspondence manner, a horizontally through air guide cavity with openings at two ends is formed between the flow guide caps and the distribution plate main body, and any two adjacent flow guide caps are arranged in a 90-degree staggered manner; and therefore, horizontal airflow sprayed from one flow guide cap can be directly blown to the side surface of the adjacent flow guide cap. Compared with the prior art, uniform fluidization of the whole catalyst bed layer can be effectively guaranteed, the problem that a traditional distribution plate is prone to material accumulation is thoroughly solved, the phenomena of local overheating and channeling are avoided, and the gas-solid contact efficiency is improved.

Description

TECHNICAL FIELD

[0001] The utility model belongs to fluidized bed reactor air distribution plate technical field relates to a kind of air distribution plate structure for hydrogen cyanide fluidized bed reactor. BACKGROUND

[0002] Hydrogen cyanide reactor is vertical skirt self-supporting fluidized bed reactor, geometric size is big, structure is complex, top is provided with gas-collecting chamber, there are multiple cyclone separators inside, heat removal water pipe group system, methanol ammonia distributor, air distribution plate and other components.This technology is to produce hydrogen cyanide under the action of catalyst with methanol, ammonia and air as raw material, while releasing a large amount of heat.Air distribution plate is an important component for uniform gas distribution and catalyst support, and its rationality directly affects the quality of gas-solid fluidization in the device and the stability of device operation, and then affects raw material conversion rate and product yield.

[0003] Traditional air distribution plate structure mainly has perforated plate, nozzle type, mushroom head type and the like.These structures often face the following problems in practical application:

[0004] (1) uneven fluidization: uneven gas distribution will lead to poor fluidization in local area, forming dead zone or channeling, affecting reaction efficiency and selectivity.

[0005] (2) catalyst accumulation: catalyst particles are prone to accumulate on the surface of distribution plate or around nozzle, leading to local overheating, caking, even plugging, affecting long-term stable operation of reactor.

[0006] (3) wear and corrosion: high-speed airflow scouring on distribution plate and nozzle and high-temperature reaction environment easily cause component wear and corrosion, shorten equipment life.

[0007] (4) difficult maintenance: once plugging or accumulation occurs, cleaning and maintenance workload is large, and downtime is long.

[0008] As provided in Chinese patent application CN112439367A, an air distribution plate includes a support plate, a gas distribution piece, a distribution pipe, and a support assembly. The gas distribution piece is a conical cylinder, and air is sprayed through the distribution pipe to form a convection with the gas outlet of the distributor, thereby achieving sufficient mixing of air, propylene, and ammonia. However, the air distribution plate of this patent has the following defects: 1) local wear and severe erosion: the vertically rising air flow directly hits the tip or slope of the inverted cone, and the high-speed impact can cause severe erosion; 2) large pressure drop: the air flow is forced to change direction from vertical to horizontal, and must pass through the narrow gap between the cone and the hole, which can cause a large resistance due to the dramatic change in flow direction and local contraction; 3) "dead zone" phenomenon of air flow distribution: after the horizontal spraying of the gas, a "blind area" or weak flow area can be formed in the center area of the inverted cone, which can easily accumulate in the low-speed area or gap, causing channel blockage; 4) high installation and centering accuracy: the relative position between the inverted cone and the inlet pipe and the support plate hole diameter must be highly accurate, making maintenance and repair difficult. Utility model content

[0009] The utility model discloses a kind of air distribution plate structures for hydrogen cyanide fluidized bed reactor, to realize more uniform fluidization, prevent catalyst accumulation, improve hydrogen cyanide production efficiency etc.

[0010] The purpose of the utility model can be realized by the following technical solutions:

[0011] An air distribution plate structure for hydrogen cyanide fluidized bed reactor, comprising:

[0012] Distribution plate main body;

[0013] A plurality of air distribution pipes are distributed in an array and vertically fixed on the distribution plate main body, for introducing air from below the distribution plate main body to above the distribution plate main body;

[0014] A plurality of flow guide caps are fixed on the distribution plate main body and correspondingly arranged above the top of the air distribution pipe. The flow guide cap and the distribution plate main body form a horizontal through air guide cavity with both ends open, to block the top of the air distribution pipe and horizontally spray the vertically introduced air. Any two adjacent flow guide caps in horizontal or vertical direction are arranged at 90° staggered, so that the horizontal air flow sprayed from one flow guide cap can directly blow to the side surface of its adjacent flow guide cap.

[0015] Further, the inner and outer side surfaces of the flow guide cap along the air guide cavity are inclined slopes, and the vertical cross section of the flow guide cap is a triangle.

[0016] Further, the included angle between the side surface of the flow guide cap and the upper surface of the distribution plate body is 45°.

[0017] Further, the flow guide cap is made of a standard angle steel.

[0018] Further, the distance between the adjacent two air distribution pipes is 3.5-4.5 times the length of the flow guide cap along the air guide cavity.

[0019] Further, the distance between the inner surface of the flow guide cap and the top end of the air distribution pipe is 0.5-0.7 times the height of the flow guide cap. The height of the flow guide cap refers to the distance between the highest point of the flow guide cap and the distribution plate body.

[0020] Further, the distribution plate body is sealingly connected with the inner wall of the cylinder of the hydrocyanic acid fluidized bed reactor through a ring plate. Further, the vertical section of the ring plate is arc-shaped.

[0021] Further, the flow guide cap and the distribution plate body are welded and fixed.

[0022] Further, the distribution plate body is circular.

[0023] Compared with the prior art, the air distribution plate structure of the utility model constructs the meshed air flow field which interweaves and collides each other above the distribution plate body through the staggered arrangement of the flow guide cap, can effectively ensure the uniform fluidization of the whole catalyst bed layer, completely solves the problem that the traditional distribution plate is easy to accumulate material, also avoids the local overheating and channeling phenomenon, and improves the gas-solid contact efficiency. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 It is a schematic view of the air distribution plate structure of the utility model;

[0025] Figure 2 It is a top view schematic view of the air distribution plate;

[0026] Figure 3 It is an enlarged schematic view of the air distribution pipe and the flow guide cap;

[0027] Figure 4 It is a schematic view of the arrangement of the flow guide cap;

[0028] Marking description in the drawing:

[0029] 1-distribution plate body, 2-air distribution pipe, 3-flow guide cap, 4-air guide cavity, 5-ring plate, 6-cylinder. DETAILED DESCRIPTION

[0030] The utility model will be described in detail below in combination with the drawings and specific embodiments. The embodiments are implemented on the premise of the technical scheme of the utility model, and detailed implementation modes and specific operation processes are given, but the protection scope of the utility model is not limited to the following embodiments.

[0031] In the description of the utility model, it needs to be explained that the orientation or position relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like is based on the orientation or position relationship shown in the drawings, and is only for the convenience of describing the utility model and simplifying the description, and does not indicate or imply that the indicated device or element must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the utility model. In addition, the terms "first", "second", "third" are only for the purpose of description, and cannot be understood as indicating or implying relative importance.

[0032] In the description of the utility model, it needs to be explained that unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connection" should be understood broadly, for example, it can be fixed connection, or detachable connection, or integrally connected; it can be mechanical connection, or electrical connection; it can be directly connected, or indirectly connected through intermediate medium, or the communication inside two elements. For ordinary skilled in the art, the specific meaning of the above terms in the utility model can be understood according to the specific circumstances.

[0033] In the following embodiments or examples, if there is no special description of the function parts or structures, it is indicated that they are all conventional parts or conventional structures adopted in the field to realize the corresponding functions.

[0034] In order to realize more uniform fluidization, prevent catalyst accumulation, improve the production efficiency of hydrogen cyanide, etc., the utility model provides an air distribution plate structure for hydrogen cyanide fluidized bed reactor, and its structure is shown in the figure, which comprises: Figures 1 to 4 The utility model discloses an air distribution plate structure for hydrogen cyanide fluidized bed reactor, which comprises:

[0035] The distribution plate body 1 is provided with a plurality of air distribution pipes 2, which are arranged in an array and vertically fixed on the distribution plate body 1, and used for introducing air from below the distribution plate body 1 to above the distribution plate body 1.

[0036] The distribution plate body 1 is provided with a plurality of air distribution pipes 2, which are arranged in an array and vertically fixed on the distribution plate body 1, and used for introducing air from below the distribution plate body 1 to above the distribution plate body 1.

[0037] Several guide caps 3 are fixed on the main body of the distribution plate and are positioned one by one above the top of the air distribution pipe 2. The guide caps 3 and the main body of the distribution plate form a horizontally penetrating air-guiding cavity 4 with open ends, which blocks the top of the air distribution pipe 2 and sprays the vertically introduced air horizontally. Any two adjacent guide caps 3 are arranged at 90° in a staggered manner along the horizontal or longitudinal direction, so that the horizontal airflow sprayed from one guide cap 3 can directly blow to the side surface of its adjacent guide cap 3.

[0038] For some specific implementation methods, please refer to [link / reference]. Figure 3 As shown, the inner and outer surfaces of the guide cap 3 along the direction of the air guide cavity 4 are both inclined slopes, making the vertical cross section of the guide cap 3 triangular. In this way, the horizontal airflow ejected from the adjacent guide cap 3 can be swept upward along the inclined slope, generating secondary disturbance and diffusion.

[0039] In a more specific embodiment, the angle between the side surface of the flow guide cap 3 and the upper surface of the distribution plate body 1 is 45°.

[0040] In a more specific embodiment, the guide cap 3 is made of standard angle steel, which facilitates the formation of the guide cap 3 with the required specific inclined slope.

[0041] For some specific implementation methods, please refer to [link / reference]. Figure 4 As shown, the spacing between two adjacent air distribution pipes 2 is 3.5 to 4.5 times the length of the guide cap 3 along the air guiding cavity 4, preferably about 4 times. For example, when using a 50mm × 50mm (length × width) guide cap 3, the spacing can be set to about 200mm. This spacing ensures sufficient fluidization space and the interaction effect of airflow, maximizing the performance of preventing material accumulation and uniform fluidization.

[0042] In some specific embodiments, the distance between the inner surface of the guide cap 3 and the top end of the air distribution pipe 2 is 0.5 to 0.7 times the height of the guide cap 3. For further details on some specific embodiments, please refer to [link to specific embodiments]. Figure 1 As shown, the main body 1 of the distribution plate is sealed to the inner wall of the cylinder 6 of the hydrogen cyanide fluidized bed reactor via an annular plate 5. Furthermore, the vertical cross-section of the annular plate 5 is arc-shaped, allowing the horizontal airflow blown out from the guide cap 3 at the edge to continue rising along the inner wall of the cylinder 6 after being guided by the arc-shaped annular plate 5, thus ensuring the fluidization effect.

[0043] In some specific embodiments, the flow guide cap 3 is welded and fixed to the distribution plate body 1.

[0044] In addition, in some specific embodiments, the main body 1 of the distribution plate, the air distribution pipe 2 and the guide cap 3 can all be made of high temperature resistant and corrosion resistant materials to adapt to the harsh working conditions of hydrogen cyanide production.

[0045] The above embodiments can be implemented individually or in any two or more combinations without violating the logic.

[0046] The above embodiments will be described in more detail below with reference to specific examples.

[0047] Example 1:

[0048] To achieve more uniform fluidization, prevent catalyst accumulation, improve hydrogen cyanide production efficiency, etc., the utility model provides an air distribution plate structure for hydrogen cyanide fluidized bed reactor, its structure refers to Figures 1 to 4 as shown, comprising:

[0049] The distribution plate body 1 is fixed on the distribution plate body 1 and is arranged one by one above the top of the air distribution pipe 2.

[0050] A plurality of air distribution pipes 2 are arranged in an array and vertically fixed on the distribution plate body 1, for introducing air from below the distribution plate body 1 to above the distribution plate body 1.

[0051] A plurality of air guide caps 3 are fixed on the distribution plate body 1 and arranged one by one above the top of the air distribution pipe 2, the air guide cap 3 and the distribution plate body 1 form a horizontal through air guide cavity 4 with both ends open, to block the top of the air distribution pipe 2 and horizontally spray the vertically introduced air, any two adjacent air guide caps 3 along the horizontal or vertical direction are arranged at 90° staggered, so that the horizontal airflow sprayed from one air guide cap 3 can directly blow to the side surface of the adjacent air guide cap 3.

[0052] Please refer to Figure 3 as shown, the inner and outer side surfaces of the air guide cap 3 along the air guide cavity 4 are inclined slopes, and the vertical section of the air guide cap 3 is a triangle, so that the horizontal airflow sprayed from the adjacent air guide cap 3 can be washed upward along the inclined slope to produce secondary disturbance and diffusion. The included angle between the side surface of the air guide cap 3 and the upper surface of the distribution plate body 1 is 45°. The air guide cap 3 is made of standard angle steel, which is convenient to form the required specific inclined slope.

[0053] Please refer to Figure 4 as shown, the distance between the two adjacent air distribution pipes 2 is 3.5-4.5 times the length of the air guide cap 3 along the air guide cavity 4, preferably about 4 times, for example, when the air guide cap 3 with a size of 50mm*50mm (length*width) is used, the distance can be set to about 200mm. This distance can not only ensure sufficient fluidization space, but also ensure the interaction effect of the airflow, maximize the performance of preventing material accumulation and uniform fluidization. The distance between the inner surface of the air guide cap 3 and the top end of the air distribution pipe 2 is 0.5-0.7 times the height of the air guide cap 3.

[0054] Please see again Figure 1 As shown in the figures, the distribution plate body 1 is connected to the inner wall of the cylinder 6 of the hydrocyanation fluidized bed reactor by a ring plate 5. Further, the vertical section of the ring plate 5 is arc-shaped, so that the horizontal air flow blown out from the edge of the flow guide cap 3 can continue to rise along the inner wall of the cylinder 6 after being guided by the arc-shaped ring plate 5, ensuring the fluidization effect. The flow guide cap 3 is fixedly welded to the distribution plate body 1.

[0055] In the air distribution plate structure of the present embodiment, the distribution plate body 1 is connected to the cylinder 6 of the hydrocyanation fluidized bed reactor by a ring plate 5, forming a sealed and load-bearing platform above which a plurality of air distribution pipes 2 are uniformly arranged. These air distribution pipes 2 are vertically welded to the distribution plate body 1, with their lower ends connected to the air inlet at the bottom of the reactor for introducing preheated air into the reactor. Above the top of each air distribution pipe 2, a flow guide cap 3 is welded at an inclined angle of about 45° to the air distribution plate. The opening of the flow guide cap 3 faces the horizontal direction, and its main function is to shield the vertical air flow from the top of the air distribution pipe 2 and force it to flow horizontally.

[0056] In the air distribution plate structure of the present embodiment, the adjacent flow guide caps 3 are arranged in a 90° staggered manner. Specifically, if the opening direction of a flow guide cap 3 points to the X-axis direction, then the opening direction of its adjacent flow guide cap 3 points to the positive or negative direction of the Y-axis. This staggered arrangement ensures that the horizontal air flow from one flow guide cap 3 can directly blow to the inclined side edge of its adjacent flow guide cap 3.

[0057] In this way, when air flows out from the top of the air distribution pipe 2 during operation, it is first shielded by the flow guide cap 3 above, and then sprayed out horizontally along the gap between the flow guide cap 3 and the air distribution plate, i.e. the air guiding cavity 4. Due to the 90° staggered arrangement of the adjacent flow guide caps 3, these horizontal air flows form a meshed air flow field above the distribution plate body 1, with the air flows from one flow guide cap 3 colliding with the inclined side edge of its adjacent flow guide cap 3, causing secondary disturbance and diffusion, and thus forming a uniform and strong horizontal scouring effect on the surface of the entire distribution plate body 1. This horizontal scouring effect can effectively prevent catalyst particles from accumulating on the surface of the distribution plate body 1 and in the dead corners around the flow guide caps 3. Even if a small amount of particles settle, they will be blown away by the continuous horizontal air flow and re-entrained in the fluidized state, thus completely solving the problem of material accumulation in traditional distribution plates. At the same time, this uniform horizontal air flow distribution ensures uniform fluidization of the entire bed layer, avoiding local overheating and channeling, and improving the gas-solid contact efficiency.

[0058] In the embodiment, since the inner side surface of the flow guide cap 3 is also a slope instead of being horizontally or vertically placed, when the air below gushes upward vertically through the air distribution pipe 2, the first contact is the inner slope of the angle steel cap, and the inclined contact angle can convert the "positive impact" of kinetic energy into "sliding turning", greatly reducing the normal impact force of the airflow on the metal surface, thereby reducing the local erosion. At the same time, after the airflow flows out of the angle steel cap and blows towards the "inclined side" of the adjacent flow guide cap 3, since the receiving end is also a slope, the direct vertical bombardment of the high-pressure airflow on the metal component is avoided, effectively prolonging the service life of the distribution plate assembly. In addition, in cooperation with the horizontal airflow at the outlet of the flow guide cap 3, the catalyst can be kept in dynamic suspension on the surface of the distribution plate, avoiding the accumulation of a large number of particles near the nozzle, and reducing the wear of the components by the gas-solid two-phase flow.

[0059] In addition, the flow guide cap 3 of the embodiment forms an expanded flow guide space at the top outlet of the air distribution pipe 2, and the process of changing the airflow from vertical to horizontal is completed in a triangular space. This non-right-angle transition is more in line with the principles of fluid mechanics, reduces the vortex generated during the turning of the airflow, and thus reduces the local resistance coefficient. The horizontal and vertical airflow above the upper surface of the distribution plate main body 1 forms an orderly circulation network, and the residual pressure airflow discharged from the previous flow guide cap 3 can guide the airflow of the next region, forming a "relay" effect, which reduces the energy dissipation caused by chaotic collision of the airflow.

[0060] As for the problem of airflow distribution dead zone, in the embodiment, the airflow is forced to change to the horizontal direction, and the airflow flows along the surface of the distribution plate, so that the catalyst cannot stay on the plate surface; at the same time, the adjacent flow guide caps 3 are arranged at 90°, which means that the airflow is interlaced in the X-axis and Y-axis directions. The airflow from the A angle steel blows towards the side surface of the B angle steel, and this cross coverage ensures that any point on the distribution plate main body 1 can be washed by the airflow from at least one direction, completely eliminating the dead angle of airflow distribution; in addition, the design of the inclined slope of the airflow towards the adjacent flow guide cap 3 not only ensures the uniformity of the airflow, but also blows away the catalyst particles that may deposit at the root of the flow guide cap 3, realizes self-cleaning of the structure, and ensures the stability of the fluidization quality in long-term operation.

[0061] The above description of the embodiments is for the convenience of those of ordinary skill in the art to understand and use the utility model. Those skilled in the art can easily make various modifications to these embodiments, and apply the general principles described herein to other embodiments without creative labor. Therefore, the utility model is not limited to the above embodiments, and those skilled in the art can make improvements and modifications within the scope of the utility model without departing from the scope of the utility model.

Claims

1. An air distribution plate structure for a fluidized bed reactor of hydrogen cyanide, characterized in that, include: Distribution plate main body; Several air distribution pipes are arranged in an array and vertically fixed on the main body of the distribution plate, used to introduce air from below the main body of the distribution plate to above the main body of the distribution plate; Several air guide caps are fixed on the main body of the distribution plate and are positioned one by one above the top of the air distribution pipe. A horizontally penetrating air guide cavity with open ends is formed between the air guide caps and the main body of the distribution plate to block the top of the air distribution pipe and eject the vertically introduced air horizontally. Any two adjacent air guide caps are arranged at 90° in a staggered manner along the horizontal or longitudinal direction, so that the horizontal airflow ejected from one air guide cap can directly blow to the side surface of its adjacent air guide cap. The inner and outer surfaces of the flow guide cap along the direction of the air guide cavity are inclined slopes, making the vertical cross-section of the flow guide cap triangular.

2. The air distribution plate structure for a fluidized bed reactor of hydrogen cyanide according to claim 1, characterized in that, The angle between the side surface of the flow guide cap and the upper surface of the distribution plate body is 45°.

3. The air distribution plate structure for a fluidized bed reactor of hydrogen cyanide according to claim 1, characterized in that, The distance between two adjacent air distribution pipes is 3.5 to 4.5 times the length of the guide cap along the air guide cavity.

4. The air distribution plate structure for a fluidized bed reactor of hydrogen cyanide according to claim 1, characterized in that, The distance between the inner surface of the air guide cap and the top of the air distribution tube is 0.5 to 0.7 times the height of the air guide cap.

5. The air distribution plate structure for a fluidized bed reactor of hydrogen cyanide according to claim 1, characterized in that, The main body of the distribution plate is sealed to the inner wall of the cylinder of the hydrogen cyanide fluidized bed reactor through a ring plate.

6. The air distribution plate structure for a fluidized bed reactor of hydrogen cyanide according to claim 5, characterized in that, The vertical cross-section of the ring plate is arc-shaped.

7. The air distribution plate structure for a fluidized bed reactor of hydrogen cyanide according to claim 1, characterized in that, The flow guide cap is welded and fixed to the main body of the distribution plate.

8. The air distribution plate structure for a fluidized bed reactor of hydrogen cyanide according to claim 1, characterized in that, The main body of the distribution plate is circular.

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