Nozzle for cold hydrogenation fluidized bed and cold hydrogenation fluidized bed

Abstract

The application provides a nozzle applied to a cold hydrogenation fluidized bed and the cold hydrogenation fluidized bed. The nozzle comprises a riser, a cone cap arranged at the top end of the riser, and a plurality of outer pipes connected to the riser near the top. The plurality of outer pipes are arranged uniformly along the circumference of the riser and are arranged obliquely downward. The riser and the plurality of outer pipes are in communication, so that the gas rising from the riser is sprayed obliquely downward through the obliquely arranged outer pipes. The nozzle provided by the application connects the obliquely downward outer pipes outside the riser, so that the gas is sprayed obliquely downward from the outer pipes after entering the riser, thereby avoiding nozzle blockage.

Description

Technical Field

[0001] This application relates to the field of chemical equipment technology, and in particular to a nozzle for use in a cold hydrogenation fluidized bed and a cold hydrogenation fluidized bed using the nozzle. Background Technology

[0002] Currently, most polysilicon plants in China employ a modified Siemens process. Silicon tetrachloride, a byproduct of this process, is converted into trichlorosilane using a "cold hydrogenation" process, enabling recycling. The cold hydrogenation fluidized bed is the core equipment in this process. The gas distribution plate is a key internal component of the cold hydrogenation reactor; currently, concave structures with nozzles are commonly used. The nozzles use high-speed airflow to propel the falling silicon powder upwards from the fluidized bed reactor, fluidizing the material.

[0003] Most existing nozzles adopt a tubular direct-flow structure, where the nozzle ejects material at high speed from a small orifice, which then enters the bed through an enlarged diameter. This structure is simple and easy to disassemble and maintain; however, the small orifice is prone to clogging when the nozzle is placed on the bed, and material leakage is likely when the bed is stopped. Summary of the Invention

[0004] The purpose of this application is to provide a nozzle for use in a cold hydrogenation fluidized bed, wherein several outer tubes are connected to the side of the riser tube and the outer tubes are inclined downward, which solves the problem of easy clogging of nozzles in the prior art.

[0005] To achieve one of the above-mentioned objectives, one embodiment of this application provides a nozzle for use in a cold hydrogenated fluidized bed, comprising a riser pipe, a cone cap disposed at the top of the riser pipe, and a plurality of outer pipes connected to the riser pipe near the top. The plurality of outer pipes are evenly spaced along the circumference of the riser pipe and are inclined downward. The riser pipe and the plurality of outer pipes are all connected, so that gas rises from the riser pipe and is ejected inclined downward through the inclined outer pipes.

[0006] As a further improvement of one embodiment of this application, the included angle between the outer tube and the riser tube is 45~60°.

[0007] As a further improvement of one embodiment of this application, the inner diameter of the riser pipe is 56.1~92.3mm, and the inner diameter of the outer pipe is 24.7~34.2mm; an orifice plate is provided inside the outer pipe, and the orifice plate has vent holes with a diameter of 8.5~12.7mm.

[0008] As a further improvement of one embodiment of this application, the total height of the nozzle is 450~600mm.

[0009] As a further improvement of one embodiment of this application, the nozzle surface is coated with tungsten carbide or Ni-Cr alloy.

[0010] One embodiment of this application also provides a cold hydrogenation fluidized bed, including a tank, a distribution plate disposed in the tank, and a nozzle. The distribution plate is connected to the inner wall of the tank and divides the space inside the tank into an air inlet chamber located below the distribution plate and a reaction chamber located above the distribution plate. The distribution plate is a concave structure with the concave surface facing upward and is provided with multiple through holes. The nozzle is the nozzle as described above and is fixed to the distribution plate through the through holes.

[0011] As a further improvement of one embodiment of this application, the outer tube is provided with three nozzles, and the nozzles include a first nozzle group and a second nozzle group. In the first nozzle group, three adjacent nozzles are arranged in an equilateral triangle, or four adjacent nozzle groups are arranged in a square. In the second nozzle group, multiple nozzles are arranged in a circular and evenly spaced manner, so that the nozzles of the second nozzle group are equidistant from the inner wall of the tank and surround the first nozzle group in the radial direction.

[0012] As a further improvement of one embodiment of this application, the cold hydrogenation fluidized bed also includes a base with an annular structure, the base passing through a through hole and fixed to a distribution plate, and the nozzle being threadedly connected to the base.

[0013] As a further improvement of one embodiment of this application, the height of the curved surface of the concave structure distribution plate is 10 to 20% of the diameter of the distribution plate.

[0014] As a further improvement of one embodiment of this application, the tank corresponding to the air inlet chamber is conical, and the cold hydrogenation fluidized bed further includes a sleeve, the bottom of which is fixed to the top of the conical part in the tank, and the distribution plate is fixed to the sleeve.

[0015] One or more technical solutions provided in this application have at least the following technical effects or advantages: The nozzle provided in this application for use in a cold hydrogenation fluidized bed includes a riser pipe and an outer casing connected to the riser pipe. The outer casing is inclined downwards, and the conical cap at the top of the riser pipe prevents silicon powder accumulation. The inclined outer casing causes the gas entering the nozzle to be sprayed out at an angle downwards. On the one hand, this can prevent particles from accumulating near the distribution plate, reduce local dead zones, and improve the fluidization uniformity of the bed. On the other hand, it will generate a horizontal thrust on the particles in the bed, promote the movement of particles along the inclined direction, break the single flow mode of vertical blowing, and form a complex three-dimensional flow field, which can increase the residence time of the gas in the bed and improve the conversion rate of reaction with silicon powder. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the nozzle structure in an embodiment of this application.

[0017] Figure 2 This is a schematic diagram of the cold hydrogenation fluidized bed portion in the embodiments of this application.

[0018] Figure 3 This is a top view of the distribution plate and the nozzles on it.

[0019] 1. Nozzle; 11. Ascendant pipe; 12. Cone cap; 13. Outer pipe; 14. Orifice plate; 141. Vent hole; 15. Connecting pipe; 2. Tank body; 21. Inlet section; 210. Inlet chamber; 211. Inlet port; 220. Reaction chamber; 3. Distribution plate; 4. Base; 5. Sleeve. Detailed Implementation

[0020] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0021] The terms used in this document, such as “center,” “upper,” “lower,” “front,” “rear,” “left,” “right,” “vertical,” “horizontal,” “top,” “bottom,” “inner,” and “outer,” indicating spatial relative positions, are used for illustrative purposes to describe the relationship of one unit or feature relative to another unit or feature as shown in the accompanying drawings. The terms “spatial relative positions” may be intended to include different orientations of the equipment in use or operation other than those shown in the figures.

[0022] For example, if the device in the figure is flipped, a unit described as being "below" or "under" other units or features will be "above" other units or features. Therefore, the exemplary term "below" can encompass both above and below orientations. The device may be oriented in other ways (rotated 90 degrees or otherwise), and the spatially related descriptive terms used herein will be interpreted accordingly.

[0023] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0024] Furthermore, it should be understood that although the terms "first," "second," etc., may be used herein to describe various elements or structures, the objects described should not be limited by these terms. These terms are only used to distinguish these objects from one another. For example, a first wireless communication device may be referred to as a second wireless communication device, and similarly, a second wireless communication device may be referred to as a first wireless communication device, without departing from the scope of protection of this application.

[0025] This application provides a nozzle 1 for use in a cold hydrogenation fluidized bed, such as... Figure 1 As shown, it includes a riser pipe 11, a cone cap 12 disposed at the top of the riser pipe 11, and several outer pipes 13 connected to the riser pipe 11 near the top. The several outer pipes 13 are evenly spaced along the circumference of the riser pipe 11 and are inclined downward. The riser pipe 11 and the several outer pipes 13 are all connected, so that after the gas rises from the riser pipe 11, it is ejected inclined downward through the inclined outer pipes 13.

[0026] With the cooperation of the riser pipe 11 and several outer pipes 13, the gas enters the nozzle 1 and then turns at the connection between the riser pipe 11 and the outer pipe 13 before being sprayed out obliquely downwards. The oblique gas outlet direction can prevent silicon powder from clogging the nozzle 1, and the obliquely sprayed gas can disturb the silicon powder deposited in the cold hydrogenation fluidized bed, so that it can participate in the reaction again.

[0027] The conical cap 12 at the top of the riser tube 11 allows silicon powder to slide down the conical surface, preventing silicon powder accumulation. The apex angle of the conical cap 12 is 60~110°, which helps the silicon powder slide down and reduces silicon powder accumulation. Preferably, it is 70°.

[0028] Furthermore, the top of the cone cap 12 is spherical, and when cut along the central axis of the cone cap 12, the top of the cone cap 12 is arc-shaped, and the corresponding arc radius is 60mm.

[0029] The number of outer tubes 13 of nozzle 1 is preferably three or four. The three or four outer tubes 13 are evenly spaced outside the riser tube 11, that is, the three or four outer tubes 13 form an equilateral triangle or a square outside the riser tube 11.

[0030] If there are too few outer tubes 13, more nozzles 1 need to be set in the cold hydrogenation fluidized bed to match the air intake and pressure drop of the cold hydrogenation fluidized bed; if there are too many outer tubes 13, fewer nozzles 1 will be set, and there will be places where the gas cannot be blown between adjacent nozzles 1, i.e. dead zones, which can easily cause silicon powder to accumulate.

[0031] In some embodiments of this application, the angle between the outer tube 13 and the riser tube 11 is 45~60°. After determining the number of nozzles 1 in the cold hydrogenation fluidized bed according to requirements, the angle between the outer tube 13 and the riser tube 11 of the nozzle 1 provided in this application is within this angle range, which can make the cold hydrogenation fluidized bed free of dead zones.

[0032] In some embodiments of this application, the inner diameter of the riser pipe 11 is 56.1~92.3mm, and the inner diameter of the outer pipe 13 is 24.7~34.2mm; an orifice plate 14 is provided inside the outer pipe 13, and the orifice plate 14 has a vent hole 141 with a diameter of 8.5~12.7mm.

[0033] The inner diameters of the riser pipe 11, outer pipe 13, and vent 141 gradually decrease, and the gas pressure gradually decreases after entering the nozzle 1. The vent 141 plays the role of pressure reduction and uniform airflow distribution.

[0034] In some embodiments of this application, the total height of the nozzle 1 is 450-600 mm. Furthermore, the distance between the outlet at the lower end of the outer tube 13 and the distribution plate 3 (described below) is 150-250 mm.

[0035] In some embodiments of this application, the surface of the nozzle 1 is coated with tungsten carbide or Ni-Cr alloy, which can better resist particle wear and high-temperature chloride ion and hydrogen chloride corrosion.

[0036] Furthermore, the nozzle 1 is made of nickel-based material with grade Hastelloy C-276 and iron-nickel-based material with grade Incoloy 800H.

[0037] This application embodiment also provides a cold hydrogenation fluidized bed, including a tank body 2, a distribution plate 3 disposed inside the tank body 2, and a nozzle 1. The distribution plate 3 is connected to the inner wall of the tank body 2 and divides the space inside the tank body 2 into an air inlet chamber 210 located below the distribution plate 3 and a reaction chamber 220 located above the distribution plate 3. The distribution plate 3 is a concave structure with the concave surface facing upward and is provided with multiple through holes. The nozzle 1 is the aforementioned nozzle 1 and is fixed to the distribution plate 3 through the through holes.

[0038] The aforementioned nozzle 1 is fixed to the distribution plate 3 through a through hole, allowing the gas in the air inlet chamber 210 to enter the nozzle 1 from the bottom end of the riser pipe 11 and be sprayed out obliquely downward from the outer pipe 13, spreading along the curved surface of the concave distribution plate 3, reducing the direct impact of the airflow on the bottom of the fluidized bed and improving the fluidization uniformity.

[0039] During the cold hydrogenation reaction, the materials (such as silicon powder and hydrogen chloride) release a large amount of heat. The distribution plate 3 is in direct contact with the high-temperature fluid, causing the plate surface temperature to rise sharply. The concave structure has a larger curved surface area and a wider range of heat absorption, making it less prone to localized overheating, which could affect the material strength and lifespan.

[0040] In addition, the concave structure of the distribution plate 3 can better withstand the gravity of the material particles in the fluidized bed.

[0041] In some embodiments of this application, the outer tube 13 is provided with three nozzles, and the nozzle 1 includes a first nozzle group 1 and a second nozzle group 1. In the first nozzle group 1, three adjacent nozzles 1 are arranged in an equilateral triangle, or four adjacent nozzle groups 1 are arranged in a square. In the second nozzle group 1, multiple nozzles 1 are arranged in a circular and evenly spaced manner, such that the nozzles 1 of the second nozzle group 1 are equidistant from the inner wall of the tank 2 and surround the first nozzle group 1 in the radial direction.

[0042] The arrangement of nozzles 1 in an equilateral triangle or square pattern specifically refers to points at the same height on the central axis of the riser pipe 11 forming an equilateral triangle or square.

[0043] As shown in the figure, in the first nozzle group 1, three adjacent nozzles 1 are arranged in an equilateral triangle, and the three cone caps 12 form a small cone bed. This creates countless small cone beds, which helps to improve the fluidization quality.

[0044] The second set of nozzles is distributed on a circle centered at a point on the central axis of the tank 2. This ensures that the nozzles 1 of the second set of nozzles are equidistant from the inner wall of the tank 2, preventing insufficient gas dynamics around the inner wall of the tank 2, which could lead to abnormal density distribution of solid particles and areas of flow deviation or blowout. This promotes sufficient gas-solid contact, further improves the fluidization state, and increases the conversion rate with silicon powder.

[0045] In some embodiments of this application, the cold hydrogenation fluidized bed provided in this application also includes a base 4 with an annular structure. The base 4 passes through a through hole and is fixed to the distribution plate 3. The nozzle 1 is connected to the base 4 by a thread.

[0046] The base 4 can be fixed to the distribution plate 3 through through holes by welding or other methods. The base 4 is provided with internal threads. The nozzle 1 also includes a connecting pipe 15 connected to the bottom of the riser pipe 11. The connecting pipe 15 is provided with external threads. The nozzle 1 is connected to the base 4 through threads, so that the nozzle 1 is fixed to the distribution plate 3.

[0047] In some embodiments of this application, the height of the concave distribution plate 3 is 10-20% of the diameter of the distribution plate 3.

[0048] A non-standard butterfly-shaped distribution plate 3 can be used. The distribution plate 3 includes a curved surface and a straight edge section. The height of the curved surface is 10-20% of the diameter of the distribution plate 3 to control the degree of concavity of the distribution plate 3.

[0049] In some embodiments of this application, the tank 2 corresponding to the air inlet chamber 210 is conical, and the cold hydrogenation fluidized bed further includes a sleeve 5. The bottom of the sleeve 5 is fixed to the top of the conical part in the tank 2, and the distribution plate 3 is fixed to the sleeve 5.

[0050] The portion of the tank 2 corresponding to the air intake chamber 210 is the air intake section 21, which has an air inlet 211 at its bottom and is in the shape of an inverted cone. Of course, if the air inlet 211 is large enough, the air intake section 21 can be in the shape of an inverted frustum.

[0051] The conical inlet section 21 has a 60° apex angle. After the gas enters the inlet chamber 210, it diffuses along the conical surface, so that the gas evenly covers the entire fluidized bed cross section and can evenly enter each nozzle 1. Furthermore, the conical inlet section 21 provides support and reinforcement for the distribution plate 3 assembly, and can better withstand the impact force of silicon powder when falling onto the bed.

[0052] The sleeve 5 can be fixed to the top of the air intake section 21 by welding or other methods. The inclined conical surface can provide upward support for the sleeve 5. Then, the distribution plate 3 is fixed to the sleeve 5.

[0053] It should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This way of describing the specification is only for clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

[0054] The detailed descriptions listed above are merely specific descriptions of feasible implementation methods of this application and are not intended to limit the scope of protection of this application. All equivalent implementation methods or modifications made without departing from the spirit of the art of this application should be included within the scope of protection of this application.

Claims

1. A nozzle for use in a cold hydrogenation fluidized bed, characterized in that, It includes a riser pipe, a cone cap set at the top of the riser pipe, and several outer pipes connected to the riser pipe near the top. The several outer pipes are evenly spaced along the circumference of the riser pipe and are inclined downward. The riser pipe and the several outer pipes are all connected, so that the gas rises from the riser pipe and is ejected inclined downward through the inclined outer pipes.

2. The nozzle for use in a cold hydrogenation fluidized bed according to claim 1, characterized in that, The angle between the outer tube and the riser tube is 45~60°.

3. The nozzle for use in a cold hydrogenation fluidized bed according to claim 1, characterized in that, The inner diameter of the riser pipe is 56.1~92.3mm, and the inner diameter of the outer pipe is 24.7~34.2mm; an orifice plate is provided inside the outer pipe, and the orifice plate has vent holes with a diameter of 8.5~12.7mm.

4. The nozzle for use in a cold hydrogenation fluidized bed according to claim 3, characterized in that, The total height of the nozzle is 450~600mm.

5. The nozzle for use in a cold hydrogenation fluidized bed according to any one of claims 1 to 4, characterized in that, The nozzle surface is coated with tungsten carbide or Ni-Cr alloy.

6. A cold hydrogenation fluidized bed, characterized in that, The device includes a tank, a distribution plate disposed within the tank, and a nozzle. The distribution plate is connected to the inner wall of the tank and divides the space within the tank into an air inlet chamber located below the distribution plate and a reaction chamber located above the distribution plate. The distribution plate is a concave structure with its concave surface facing upward and is provided with multiple through holes. The nozzle is the nozzle described in any one of claims 1 to 5 and is fixed to the distribution plate through the through holes.

7. The cold hydrogenation fluidized bed according to claim 6, characterized in that, The outer tube is provided with three nozzles, and the nozzles include a first nozzle group and a second nozzle group. In the first nozzle group, three adjacent nozzles are arranged in an equilateral triangle, or four adjacent nozzle groups are arranged in a square. In the second nozzle group, multiple nozzles are arranged in a circular and evenly spaced manner, so that the nozzles of the second nozzle group are equidistant from the inner wall of the tank and surround the first nozzle group in the radial direction.

8. The cold hydrogenation fluidized bed according to claim 6, characterized in that, It also includes a ring-shaped base, which passes through a through hole and is fixed to the distribution plate, and the nozzle is connected to the base by a thread.

9. The cold hydrogenation fluidized bed according to claim 6, characterized in that, The height of the concave distribution plate is 10-20% of the diameter of the distribution plate.

10. The cold hydrogenation fluidized bed according to claim 6, characterized in that, The tank corresponding to the air inlet chamber is conical in shape. The cold hydrogenated fluidized bed also includes a sleeve. The bottom of the sleeve is fixed to the top of the conical part in the tank, and the distribution plate is fixed to the sleeve.

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