Fouling unit, fouling apparatus, hydrogenation reactor, and fouling method

Abstract

A fouling unit (1), comprising: an internal cylinder (11) and a plurality of curved baffles (12), wherein the internal cylinder (11) is formed by a mesh structure, defines a central axis (20), and comprises a cylindrical internal volume (113); and the plurality of curved baffles (12) are uniformly distributed circumferentially around the internal cylinder (11) and extend outward from the outer periphery of the internal cylinder (11), thereby forming annular flow channels between adjacent curved baffles (12). The present invention further relates to a fouling apparatus comprising the fouling unit (1), a hydrogenation reactor (100) comprising the fouling apparatus, and a fouling method using the fouling apparatus.

Description

Descaling unit, descaling device, hydrogenation reactor and descaling method Technical Field

[0001] This invention relates to liquid-solid separation technology in the petrochemical field, and more specifically to a fouling unit, a fouling device including the fouling unit, a hydrogenation reactor including the fouling device, and a fouling method. Background Technology

[0002] The information provided in this section is for the purpose of presenting the general background of this disclosure. To the extent described in this section, the work of the currently named inventors and aspects that may not otherwise be described as prior art at the time of filing are neither explicitly nor implicitly considered as prior art to this disclosure.

[0003] In the petroleum refining industry, the liquid phase feed in a fixed-bed hydrotreating reactor contains small amounts of impurities such as oil coke, as well as rust and fouling generated by the impact on pipelines and equipment during flow. Typically, the fouling in the hydrotreating feed includes suspended particulate matter of metal salts such as iron and calcium, carbon deposits, and mechanical impurities, collectively referred to as fouling particles in this paper. When liquid phase feed carrying fouling particles flows through the catalyst bed, it rapidly blocks the flow channels, leading to uneven distribution of the liquid phase feed in the bed, reducing catalyst efficiency. Furthermore, the fouling particles can combine with carbon deposits generated during the reaction to form a fouling layer. This fouling layer accumulates on the surface of the catalyst bed, forming a capping layer on top of the catalyst. This capping layer increases the pressure drop within the reactor, affecting fluid distribution within the reactor area, reducing catalyst efficiency, increasing system energy consumption, and even damaging internal components such as trays. Meanwhile, hydrogenation is an exothermic reaction, which can easily create a temperature difference in the radial cross-section of the catalyst bed. The presence of scale reduces the heat release from the bed, leading to local overheating, causing temperature hotspots in the catalyst bed, damaging the catalyst's performance, and thus greatly reducing the catalyst's service life.

[0004] To address the aforementioned problems, existing technologies typically employ numerous fouling baskets at the top of the reactor. These baskets are open-top, bottom-sealed baskets constructed from stainless steel woven wire mesh or Johnson's mesh and a frame. The baskets are filled with a protective agent / filler to trap fouling particles before they enter the catalyst bed. For example, Chinese patent application CN116351333A discloses a filtration device and reactor, belonging to the technical field of filtration equipment. The filtration device includes a housing, a mounting plate, and fouling baskets. The housing has a first inlet. The mounting plate is disposed within the housing, dividing it into an upper and lower cavity. The fouling baskets are connected to the mounting plate and located within the lower cavity. The fouling baskets have a second inlet. The mounting plate has a downcomer hole communicating with the second inlet, the height of which is lower than the opening height of the downcomer hole. The reaction liquid, entering the shell through the first inlet, reaches the mounting plate and then flows into the fouling basket through the downcomer. This prevents the reaction liquid from accumulating on the mounting plate and causing impurities to deposit there, thus avoiding corrosion and damage to the mounting plate and improving the reliability and durability of the filtration device. This type of fouling basket has a high dirt-holding capacity and can be used for extended periods, reducing the rate of pressure drop increase in the bed and ensuring long-term operation of the hydrogenation reactor. However, the large number of fouling baskets results in low space utilization. Because the liquid material flows primarily radially during filtration, the flow path and residence time within the fouling basket are relatively short, making it difficult to achieve the desired filtration and deposition effect.

[0005] Therefore, there is a need for a fouling device, a hydrogenation reactor including the fouling device, and a fouling method using the fouling device, which can not only effectively improve space utilization, but also effectively extend the flow path and residence time of liquid materials. Summary of the Invention

[0006] The purpose of this invention is to provide a fouling device, a hydrogenation reactor including the fouling device, and a fouling method using the fouling device. Through the gradually opening flow channel (quasi-annular flow channel) design of the fouling unit of the fouling device, physical sedimentation, adsorption, and multi-stage filtration of fouling particles can be achieved, which not only effectively improves space utilization but also effectively extends the flow path and residence time of liquid materials.

[0007] To achieve the above objectives, according to a first aspect of the present invention, a fouling unit is provided, comprising: an inner cylinder formed of a mesh structure, defining a central axis and including a cylindrical internal volume; and a plurality of curved baffles uniformly distributed circumferentially around the inner cylinder and extending outward from the outer periphery of the inner cylinder, thereby forming an annular flow channel between adjacent curved baffles.

[0008] The plurality of curved baffles have an involute shape in cross-section perpendicular to the central axis, thereby forming an involute flow channel between adjacent curved baffles. At least one of the plurality of curved baffles has a mesh structure. Liquid material is introduced from the radially outer side of the curved baffles and accumulates on the scale plate to form a precipitate. Under the hydrostatic pressure of the precipitate, the liquid material generates both circumferential flow along the involute flow channel and radial permeation from the outside to the inside through the curved baffles, causing scale particles in the liquid material to undergo sedimentation, adsorption, and multi-stage filtration to form filtered liquid material. The filtered liquid material enters the inner cylinder and descends along the internal volume of the inner cylinder and flows out through the outlet in the scale plate.

[0009] Furthermore, in the above technical solution, the inner cylinder may include an outer ring and an inner ring, both of which are mesh structures. The outer ring and the inner ring are spaced apart from each other to form an annular space between the outer ring and the inner ring. The annular space of the inner cylinder is filled with scale-inhibiting filler or a folded structure configured to block the scale particles.

[0010] Furthermore, in the above technical solution, the curved baffle plate may have a locally recessed or convex structure in the cross-section perpendicular to the central axis.

[0011] Furthermore, in the above technical solution, the curved baffle plate can be a smooth curve or a sawtooth shape in the cross section perpendicular to the central axis.

[0012] Furthermore, in the above technical solution, the curved baffle can be formed by a single layer or multiple layers of mesh structure, and the outer ring and inner ring of the inner cylinder can be formed by a single layer or multiple layers of mesh structure.

[0013] Furthermore, in the above technical solution, the radial dimension of the annular space of the inner cylinder can be at least 50 mm.

[0014] Furthermore, in the above technical solution, the filling height of the scale inhibitor packing can be lower than the upper edge of the inner cylinder by a predetermined height H, so as to form a top radial overflow channel with a predetermined height H. The top radial overflow channel is configured such that when the scale layer of the accumulated scale particles is level with the filling height of the scale inhibitor packing in the gradually opening flow channel, the liquid phase material bypasses the scale inhibitor packing from the outside to the inside and enters the internal volume of the inner cylinder.

[0015] Furthermore, in the above technical solution, each scale accumulation unit may also include a top plate and a bottom plate, the top plate and the bottom plate being configured to respectively close the upper end and the lower end of the gradually opening flow channel; the top plate is provided with an inlet for gaseous material to pass through at a position corresponding to the inner ring of the inner cylinder, and the bottom plate is provided with an outlet for both liquid and gaseous material to pass through at a position corresponding to the inner ring of the inner cylinder.

[0016] Furthermore, in the above technical solution, each scale accumulation unit may also include a hollowed-out annular pressure plate located on the top plate, the annular pressure plate being configured as a channel for gaseous materials to directly enter the internal volume of the inner cylinder.

[0017] Furthermore, in the above technical solution, each scale accumulation unit may also include a cover plate located on the annular pressure plate. The cover plate is provided with a plurality of circumferentially extending buffer grooves on its radially outer side. The buffer grooves are configured to reduce the impact and rebound of the liquid phase material from above and to uniformly guide the liquid phase material onto the scale accumulation plate.

[0018] Furthermore, in the above technical solution, each scale accumulation unit may also include a fixed connector located at the bottom of the inner cylinder. The fixed connector is hollow, extends through the outlet in the scale accumulation pan, and extends upward beyond the bottom plate by a certain distance to help form liquid accumulation of liquid phase material on the scale accumulation pan. It is configured to form a fixed connection between the inner ring of the inner cylinder and the bottom plate and the scale accumulation pan.

[0019] According to a second aspect of the present invention, a hydrogenation reactor is provided, comprising the aforementioned fouling device, wherein a plurality of fouling units are arranged at uniform intervals on a fouling plate.

[0020] Furthermore, in the above technical solution, the scale buildup unit is arranged in a multi-layered manner.

[0021] According to a third aspect of the present invention, a method for descaling using the descaling device described above is provided, comprising the following steps:

[0022] A. As the liquid level of the liquid material on the scale plate rises, the liquid material generates both circumferential flow along the gradually opening flow channel and radial penetration from the outside to the inside through the curved baffle plate under the static pressure of the accumulated liquid.

[0023] B. In the circumferential flow of liquid material, scale particles undergo solid-liquid separation through physical sedimentation under the action of gravity and centrifugal force generated by the circumferential flow, and the scale particles settle on the bottom plate.

[0024] C. During the circumferential flow, due to the sidewall effect, a velocity difference is formed between the liquid phase material near the curved baffle and the liquid phase material in the central region. Deposits in the lower-velocity liquid phase material near the curved baffle are adsorbed at the mesh of the baffle; and

[0025] D. The radially permeated liquid material passes through the curved baffle plate from the outside to the inside. During the radial permeation process, the scale particles are filtered through the curved baffle plate in multiple stages.

[0026] Furthermore, in the above technical solution, the method for removing scale may also include the following steps:

[0027] E. When the liquid material flows through the inner cylinder, the scale particles in the liquid material are further filtered by the metal mesh structure of the outer and inner rings of the inner cylinder, and adsorbed and filtered by scale-inhibiting packing or pleated structure; and / or

[0028] F. When the accumulated scale layer of the scale particles is level with the filling height of the scale inhibitor packing in the gradually opening flow channel, the liquid phase material bypasses the scale inhibitor packing from the outside to the inside and enters the internal volume of the inner cylinder.

[0029] The present invention has the following beneficial effects:

[0030] 1) This invention, through the design of an internal cylinder and multiple involute-shaped curved baffles extending outwards, constructs multiple relatively independent involute flow channels circumferentially on the outer side of the internal cylinder. Therefore, under the static pressure of the accumulated liquid, both circumferential and radial permeation of the liquid material can be formed. When the liquid material flows along the involute flow channels, scale particles can settle to the bottom plate, while scale particles entrained in the liquid material near the curved baffles will be adsorbed onto the curved baffles; simultaneously, due to the mesh design of the curved baffles, multi-layer filtration of scale particles can be achieved during the radial permeation of the liquid material from the outside to the inside. When the liquid material flows into the internal cylinder, scale particles can be further adsorbed and filtered by scale-inhibiting packing, or intercepted by folded structures. Thus, the liquid material pretreated by the scale-accumulation unit of the scale-accumulation device flows out of the internal cylinder and can undergo a hydrogenation reaction. The slow flow of liquid material in the gradually opening channel of the present invention provides sufficient time and space for sedimentation, separation and adsorption of scale particles, thus effectively improving the separation and treatment efficiency of scale compared with the prior art.

[0031] 2) According to the present invention, the curved baffle plate may have a locally recessed or convex structure. This locally recessed or convex structure can locally change the flow direction of the liquid phase material during circumferential flow, allowing exchange of liquid phase material between the sidewalls and the center of the involute channel, which helps to increase the adsorption capacity of scale particles. Furthermore, a uniform scale particle concentration also helps to maintain a uniform scale settling height along the circumference of the bottom plate.

[0032] 3) According to the present invention, the curved baffle can adopt a serrated folded shape (similar to a folding fan structure). Through the folded structural design, the interception area of ​​dirt particles can be effectively increased, thereby improving the interception efficiency.

[0033] 4) According to the present invention, the filling height of the scale inhibitor packing can be lower than the upper edge of the inner cylinder by a predetermined height H, so as to form a top radial overflow channel with a predetermined height H. Thus, when the accumulated scale layer of the scale particles is level with the filling height of the scale inhibitor packing in the gradually opening flow channel, the liquid material bypasses the scale inhibitor packing from the outside to the inside and enters the internal volume of the inner cylinder. This not only ensures that the local pressure drop does not rise rapidly through overflow, but also ensures the continuity of liquid material feeding. Furthermore, an alarm can be triggered to promptly clean or replace the scale-accumulating unit.

[0034] 5) According to the present invention, a plurality of circumferentially extending buffer grooves are provided on the radially outer side of the scale accumulation unit cover plate. The buffer grooves can be used to reduce the impact and rebound of liquid material from above, and to guide the liquid material evenly to the scale accumulation plate. Therefore, the liquid material can be evenly distributed, avoiding uneven distribution of liquid material to avoid the formation of a liquid level difference on the scale accumulation plate.

[0035] 6) According to the present invention, the involute flow channel technology can significantly improve the space utilization rate of the scale buildup unit in the hydrogenation reactor and enhance the scale holding capacity; through physical sedimentation, adsorption and multi-stage filtration separation processes, it not only extends the residence time of liquid materials in the separation processes such as filtration, adsorption and sedimentation, making the separation process more thorough and effective, but also helps to slow down the pressure drop increase of the catalyst bed in the hydrogenation reactor.

[0036] 7) According to the present invention, the scale buildup unit has a simple structure, is easy to install and disassemble, is easy to clean and reuse, and can be used in the form of scale-free packing, eliminating the need to replace scale-free packing and extending service life.

[0037] The foregoing summary is not intended to represent every embodiment or aspect of this disclosure. Rather, it merely provides examples of some novel concepts and features set forth herein. The foregoing features and advantages, as well as other features and accompanying advantages, will become apparent when taken in conjunction with the accompanying drawings and the appended claims, based on the following detailed description of illustrative examples and representative models for carrying out this disclosure. Furthermore, this disclosure expressly includes any and all combinations and sub-combinations of the elements and features set forth above and below. Attached Figure Description

[0038] This disclosure will be more fully understood from the detailed description and accompanying drawings.

[0039] Figure 1 is a schematic cross-sectional view of a descaling device according to an embodiment of the present invention.

[0040] Figure 2 is a schematic perspective view of the curved baffle and inner cylinder of the fouling unit of the fouling device according to an embodiment of the present invention, showing multiple gradually opening flow channels.

[0041] Figure 3 is a schematic perspective view of the relative positional relationship between a single curved baffle plate and the inner cylinder of the fouling unit of the fouling device according to an embodiment of the present invention, showing that the curved baffle plate is a smooth curve.

[0042] Figure 4A is a schematic top view of the curved baffle and inner cylinder of the fouling unit of the fouling device according to an embodiment of the present invention, showing a first embodiment of the curved baffle.

[0043] Figure 4B is a schematic top view of the curved baffle and inner cylinder of the fouling unit of the fouling device according to an embodiment of the present invention, showing a second embodiment of the curved baffle.

[0044] Figure 5 is a schematic perspective view of the relative positional relationship between a single curved baffle plate and the inner cylinder of the fouling unit of the fouling device according to an embodiment of the present invention, showing that the curved baffle plate has a sawtooth folded shape.

[0045] Figure 6 is a schematic cross-sectional view of the layout of two fouling units of the fouling device according to an embodiment of the present invention in a hydrogenation reactor.

[0046] Figure 7 is a schematic diagram of a hydrogenation reactor according to an embodiment of the present invention, including a fouling device having multiple fouling units.

[0047] This disclosure is readily adaptable to various modifications and alternatives, some representative embodiments of which are illustrated by way of example in the accompanying drawings and will be described in detail herein. However, it should be understood that the novel aspects of this disclosure are not limited to the specific forms shown in the foregoing drawings. Rather, this disclosure will cover all modifications, equivalents, combinations, sub-combinations, arrangements, groupings, and alternatives that fall within the scope of this disclosure, for example, as covered by the appended claims. Detailed Implementation

[0048] The following description is merely exemplary in nature and is not intended to limit this disclosure, its application, or its use. This disclosure is readily embodied in many forms. Representative examples of this disclosure are shown in the accompanying drawings and will be described in detail herein; it is to be understood that these embodiments are provided as illustrative of the principles of the disclosure and not as limitations on the broad aspects of this disclosure. Furthermore, the drawings are generally schematic and not necessarily drawn to scale. Some features may be exaggerated or minimized to show detail of particular components. Therefore, the specific structural and functional details disclosed herein should not be construed as limiting, but are merely intended to teach those skilled in the art a representative basis for using this disclosure in various ways. For this purpose, elements and limitations described, for example, in the abstract, background, summary, description of drawings, and detailed description sections but not expressly set forth in the claims, should not be incorporated, individually or jointly, by implication, inference, or otherwise, into the claims.

[0049] Certain terms may be used for reference only in the following description and are therefore not intended to be limiting. For example, terms such as “above” and “below” refer to orientations in the referenced figures. Terms such as “front,” “rear,” “front,” “rear,” “left,” “right,” “rear,” “side,” “up,” “down,” “top,” and “bottom” describe the orientation and / or position of parts of a component or element within a consistent but arbitrary frame of reference, as will become clear from the text describing the component or element in question and the associated figures.

[0050] Furthermore, terms such as "first," "second," and "third" may be used to describe individual components. These terms are used to describe the accompanying drawings and do not represent a limitation on the scope of this disclosure as defined by the appended claims. Additionally, the teachings may be described herein in the form of functional and / or logical block components and / or various processing steps. It should be understood that such block components may include multiple hardware, software, and / or firmware components configured to perform a specified function.

[0051] Referring now to the accompanying drawings, wherein like reference numerals denote like features throughout several views. FIG1 is a schematic cross-sectional view of a fouling device according to an embodiment of the present invention. FIG2 is a schematic perspective view of the curved baffle 12 and the inner cylinder 11 of the fouling unit 1 of the fouling device according to an embodiment of the present invention, showing a plurality of involute flow channels 120. FIG3 is a schematic perspective view of the relative positional relationship between a single curved baffle 12 and the inner cylinder 11 of the fouling unit 1 of the fouling device according to an embodiment of the present invention, showing that the curved baffle 12 is a smooth curve. FIG4A is a schematic top view of the curved baffle 12 and the inner cylinder 11 of the fouling unit 1 of the fouling device according to an embodiment of the present invention, showing a first embodiment of the curved baffle 12. FIG4B is a schematic top view of the curved baffle 12 and the inner cylinder 11 of the fouling unit 1 of the fouling device according to an embodiment of the present invention, showing a second embodiment of the curved baffle 12. Figure 5 is a schematic perspective view showing the relative positional relationship between a single curved baffle 12 and the inner cylinder 11 of the fouling unit 1 of the fouling device according to an embodiment of the present invention, illustrating that the curved baffle 12 has a serrated folded shape. The fouling device according to the present invention can be used in a hydrogenation reactor, and it should be understood that the fouling device can also be used in any other suitable application without departing from the scope of the invention.

[0052] As shown in Figures 1 to 5, the fouling device includes: a fouling disk 102; and at least one fouling unit 1 disposed on the fouling disk 102. The fouling unit 1 includes: an inner cylinder 11 formed of a mesh structure, defining a central axis 20 and including a cylindrical internal volume 113; and a plurality of curved baffles 12, the plurality of curved baffles 12 being circumferentially uniformly distributed around the inner cylinder 11 and extending outward from the outer periphery of the inner cylinder 11, thereby forming an annular flow channel between adjacent curved baffles. In one example, the plurality of curved baffles 12 have an involute shape in a cross-section perpendicular to the central axis 20, thereby forming an involute flow channel 120 between adjacent curved baffles 12. In one example, at least one of the plurality of curved baffles 12 has a mesh structure. In one example, each curved baffle 12 is formed of a mesh structure. As those skilled in the art will understand, the curved baffle 12 may also be without mesh, in which way the annular flow channel of the curved baffle 12 can extend the flow path of the liquid material to allow for sufficient fouling. The mesh structure of the curved baffle 12 can generate radial permeation from the outside to the inside through the curved baffle 12.

[0053] Liquid material is introduced from the radial outside of the curved baffle 12 and accumulates on the scale plate 102 to form a liquid. Under the static pressure of the liquid, the liquid material generates both circumferential flow along the gradually opening flow channel 120 and radial penetration from the outside to the inside through the curved baffle 12, so that the scale particles in the liquid material undergo sedimentation, adsorption and multi-stage filtration to form filtered liquid material. The filtered liquid material enters the inner cylinder 11 and descends along the internal volume 113 of the inner cylinder 11 and flows out through the outlet 18 in the scale plate 102.

[0054] The inner cylinder 11 may include an outer ring 112 and an inner ring 111. Both the outer ring 112 and the inner ring 111 are metal mesh structures, and the outer ring 112 and the inner ring 111 are spaced apart from each other to form an annular space 110 between the outer ring 112 and the inner ring 111. The annular space 110 is filled with a scale inhibitor filler 110A (as shown in FIG. 4A) or a folded structure 110B (as shown in FIG. 4B) configured to block solid particles.

[0055] According to the present invention, the scale-accumulating unit 1, through the design of an inner cylinder 11 and multiple involute curved baffles 12 extending outward, can construct multiple relatively independent involute flow channels 120 circumferentially on the outer side of the inner cylinder 11. Therefore, under the static pressure of the accumulated liquid, both circumferential flow and radial permeation of the liquid phase material can be formed. When the liquid phase material flows along the involute flow channels 120, scale particles can settle onto the bottom plate 14, while scale particles entrained in the liquid phase material near the curved baffles 12 will be adsorbed onto the curved baffles 12; at the same time, due to the mesh design of the curved baffles 12, multi-layer filtration of scale particles can be achieved during the radial permeation of the liquid phase material from the outside to the inside. When the liquid phase material flows to the inner cylinder 11, scale particles can be further adsorbed and filtered by the scale-inhibiting packing 110A, or intercepted by the scale particles through the folded structure 110B, etc. Thus, the liquid material pretreated by the scale buildup unit 1 of the scale buildup device flows out of the inner cylinder 11 and can then undergo a hydrogenation reaction. The slow flow of the liquid material in the gradually opening flow channel 120 of the present invention provides sufficient time and space for the sedimentation, separation, and adsorption of scale particles. Therefore, it can effectively improve the scale separation and treatment efficiency compared with the prior art.

[0056] The scale inhibitor packing 110A can take various structural forms such as hollow cylindrical or multi-leaf clover shape. The folded structure 110B can be an "M" shaped structure, etc. It should be understood that the scale inhibitor packing 110A and / or the folded structure 110B can take any other suitable form without departing from the scope of the invention.

[0057] The curved baffle 12 can have a regular curved shape in its cross-section perpendicular to the central axis 20 (as shown in Figure 4A), or it can have a locally recessed or raised structure (as shown in Figure 4B). This locally recessed or raised structure can locally change the flow direction of the liquid phase material during circumferential flow, allowing for the exchange of liquid phase material between the sidewalls and the center of the involute channel 120, which helps to increase the adsorption capacity of scale particles. Furthermore, a uniform scale particle concentration also helps to maintain a uniform scale settling height on the bottom plate 14.

[0058] The curved baffle 12 has a smooth curve (as shown in Figure 3) or a sawtooth shape 121 (as shown in Figure 5) in a cross-section perpendicular to the central axis 20. Through the folded structural design, the interception area of ​​dirt particles can be effectively increased, thereby improving the interception efficiency.

[0059] As shown in Figures 1 to 3, the curved baffle 12 can be formed from a single-layer or multi-layer mesh structure, and the outer ring 113 and inner ring 111 of the inner cylinder 11 can also be formed from a single-layer or multi-layer mesh structure. The mesh count (the number of meshes per inch) is between 10 and 100. The curved baffle 12 and the outer ring 112 of the inner cylinder 11 can be connected by spot welding. It should be understood that the curved baffle 12 and the outer ring 112 of the inner cylinder 11 can also be connected in any other suitable manner without departing from the scope of the invention. The curved baffle 12 adopts a mesh structure, resulting in low resistance to liquid flow and a lower overall pressure drop in the fouling unit 1. The metal mesh structure can be formed by welding parallel and cross-arranged mesh strips with vertical support strips to form the aforementioned smooth curved surface structure or folded structure. The mesh can be square, rectangular, or other shapes. The limited mesh count ensures that the mesh aperture is small enough to effectively intercept fouling particles while ensuring a certain liquid phase permeability.

[0060] The radial dimension of the annular space 110 of the inner cylinder is at least 50 mm. As used herein, "radial dimension of the annular space 110" refers to the radius difference between the outer ring 112 and the inner ring 111 of the annular space 110. The filling height of the scale inhibitor packing 110A is lower than the upper edge of the inner cylinder by a predetermined height H to form a top radial overflow channel with a predetermined height H. When the accumulated scale layer of the scale particles is level with the filling height of the scale inhibitor packing in the gradually opening flow channel (at which point the liquid phase material can no longer flow circumferentially), the liquid phase material flows from the outside to the inside through the top mesh structure of the curved baffle 12 and directly into the inner cylinder 11 (the mesh structure of the inner cylinder 11 can also be provided with openings to form an open channel, not shown in the figure), so that the liquid phase material bypasses the scale inhibitor packing 110A from the outside to the inside and enters the internal volume 113 of the inner cylinder. Therefore, the scale accumulation unit according to the present invention can not only ensure that the local pressure drop does not rise rapidly through overflow, but also ensure the continuity of liquid phase material feeding. In addition, an alarm can be triggered to promptly clean or replace the scale buildup unit 1.

[0061] As further shown in Figures 1 and 2, each fouling unit 1 may also include a top plate 13 and a bottom plate 14. The top plate 13 and the bottom plate 14 are configured to respectively close the upper and lower ends of the gradually opening flow channel 120. The top plate 13 is provided with an inlet 130 for gaseous materials to pass through at a position corresponding to the inner ring 111 of the inner cylinder 11. The bottom plate 14 is provided with an outlet for both liquid and gaseous materials to pass through at a position corresponding to the inner ring 111 of the inner cylinder 11.

[0062] Each scale buildup unit 1 may further include a perforated annular pressure plate 15 located on the top plate 13, the annular pressure plate 15 being configured to provide a channel for gaseous material to directly enter the internal volume 113 of the inner cylinder 11. Each scale buildup unit 1 may further include a cover plate 16 located on the annular pressure plate 15. The cover plate 16 has a plurality of circumferentially extending buffer grooves 161 arranged on its radially outer side, the buffer grooves 161 being configured to reduce the impact and rebound of liquid material from above, and to uniformly guide the liquid material onto the scale buildup plate, thus uniformly distributing the liquid material and avoiding uneven distribution of the liquid material to prevent the formation of a liquid level difference on the scale buildup plate 102.

[0063] Each scale buildup unit 1 may also include a fixed connector 17 located at the bottom of the inner cylinder 11. The fixed connector 17 is hollow, extends through the outlet 18 in the scale buildup tray 102, extends upward beyond the bottom plate 14 by a certain distance to facilitate the formation of liquid accumulation of liquid material on the scale buildup tray 102, and is configured to form a fixed connection between the inner ring 111 of the inner cylinder 11 and the bottom plate 14 and the scale buildup tray 102, ensuring the overall stability of the scale buildup unit 1.

[0064] According to the present invention, the involute flow channel 120 can significantly improve the space utilization of the scale buildup unit 1 in the hydrogenation reactor 100 and enhance the scale holding capacity. Through physical sedimentation, adsorption and multi-stage filtration separation processes, it not only extends the residence time of liquid materials in the separation processes such as filtration, adsorption and sedimentation, making the separation process more thorough and effective, but also helps to slow down the pressure drop increase of the catalyst bed in the hydrogenation reactor 100.

[0065] According to the present invention, the scale buildup unit 1 has a simple structure, is easy to install and disassemble, is easy to clean and reuse, and can be in the form of scale-free filler 110A, eliminating the need to replace scale-free filler 110A and extending service life.

[0066] Figure 6 is a schematic cross-sectional view of the layout of two fouling units 1 of the fouling device according to an embodiment of the present invention in a hydrogenation reactor 100. Figure 7 is a schematic diagram of a hydrogenation reactor 100 according to an embodiment of the present invention, including a fouling device having a plurality of fouling units 1.

[0067] As shown in Figures 6 and 7, a hydrogenation reactor 100 is provided, including the aforementioned fouling device. Multiple fouling units 1 are evenly spaced on a fouling plate 102. The fouling device can be installed inside the upper head 101 of the hydrogenation reactor 100; it should be understood that the fouling device can also be used as an external fouling device for the hydrogenation reactor 100. The fouling units 1 on the fouling plate 102 can be arranged in a ring-shaped interval or any other uniform manner. If there are many fouling particles, the fouling units 1 can also be arranged in two or more layers (not shown in the figures) axially in the hydrogenation reactor 100.

[0068] Further as shown in Figures 6 and 7, taking two fouling units 1 as an example, the material entering the hydrogenation reactor 100 through the inlet 103 falls onto the buffer tank 161 of the cover plate 16 after passing through the distributor (not shown in the figure). The buffer tank 161 can be used to reduce the impact and rebound of the liquid material from above and to guide the liquid material evenly to the fouling plate 102. Therefore, the liquid material can be evenly distributed to avoid uneven distribution of the liquid material and the formation of a liquid level difference on the fouling plate 102.

[0069] As the liquid level 109 of the liquid material rises, the liquid material in the scale accumulation unit 1 with the gradually opening flow channel 120 exhibits both annular flow and radial permeation (as shown by arrow 107 in Figure 6). Scale particles in the liquid material undergo sedimentation, adsorption, and multi-stage filtration to form filtered liquid material. The filtered liquid material enters the inner cylinder 11 and descends along the internal volume 113 of the inner cylinder 11, flowing out through the outlet 18 in the scale accumulation pan 102. Specifically, in the circumferential flow, scale particles in the liquid phase material undergo solid-liquid separation through physical sedimentation under the influence of gravity and centrifugal force generated by the circumferential flow, with the scale particles settling on the bottom plate 14. During the circumferential flow, due to the sidewall effect, a velocity difference is formed between the liquid phase material near the curved baffle plate 12 and the liquid phase material in the central region. Scale particles in the lower-velocity liquid phase material near the curved baffle plate 12 are adsorbed at the mesh of the curved baffle plate 12. The radially permeating liquid phase material permeates radially from the outside to the inside through the curved baffle plate 12 (as shown by arrow 107 in Figure 6). During radial permeation, the scale particles are filtered through multiple stages by the curved baffle plate 12. Separation is achieved through the size difference between the scale particles and the metal mesh; the liquid phase material can pass through the metal mesh to screen and retain scale particles larger than the mesh size within the gradually opening flow channel 120.

[0070] The gas phase inlet of the fouling unit 1 (at the starting point of the gas phase inlet arrow 106 in Figure 6) is higher than the liquid level. Most of the gas phase material enters the inner cylinder 11 through the gas phase channel 150 between the cover plate 16 and the top plate 13, while the liquid phase material mainly enters the inner cylinder 11 through annular flow and radial permeation. When the scale layer of the fouling particles on the bottom plate 14 is level with the filling height of the scale inhibitor packing 110A in the gradually opening flow channel 120 (at which point the liquid phase material can no longer flow in annular direction), the liquid phase material flows directly into the inner cylinder 11 from the outside to the inside through the top mesh structure of the curved baffle plate 12, allowing the liquid phase material to bypass the scale inhibitor packing 110A and enter the cylindrical internal volume 113 of the inner cylinder. Therefore, the fouling unit 1 according to the present invention can not only ensure that the local pressure drop does not rise rapidly through overflow, but also ensure the continuity of liquid phase material feeding. In addition, an alarm can be triggered to clean or replace the fouling unit 1 in a timely manner.

[0071] The liquid and gaseous materials entering the internal volume 113 of the inner cylinder 11 are mixed into a gas-liquid mixture, which flows out of the fouling unit 1 of the present invention through the outlet 18 of the fouling plate 102 (as shown by arrow 108 in Figure 6) and enters the catalyst bed 104 of the hydrogenation reactor 100 for catalytic reaction.

[0072] The present invention also provides a method for removing scale, comprising the following steps:

[0073] A. As the liquid level 109 of the liquid material on the scale plate 102 increases, the liquid material generates both circumferential flow along the gradually opening flow channel 120 and radial penetration from the outside to the inside through the curved baffle plate (12) under the static pressure of the accumulated liquid.

[0074] B. Under the action of gravity and centrifugal force generated by the circumferential flow, the scale particles in the liquid phase material are separated into solid and liquid through physical sedimentation, and the scale particles settle on the bottom plate 14.

[0075] C. During the circumferential flow, due to the sidewall effect, a velocity difference is formed between the liquid phase material near the curved baffle 12 and the liquid phase material in the central region. Scale particles in the lower-velocity liquid phase material near the curved baffle 12 are adsorbed at the mesh of the curved baffle 12; and

[0076] D. The radially permeated liquid material passes through the curved baffle 12 from the outside to the inside. During the radial permeation process, the scale particles are filtered through the curved baffle 12 in multiple stages.

[0077] The methods for removing scale also include the following steps:

[0078] E. When the liquid material flows through the inner cylinder, the scale particles in the liquid material are further filtered by the metal mesh structure of the outer ring 112 and inner ring 111 of the inner cylinder, and adsorbed and filtered by the scale-inhibiting packing 110A or the pleated structure 110B; and / or

[0079] F. When the accumulated scale layer of the scale particles is level with the filling height of the scale inhibitor packing in the gradually opening flow channel, the liquid phase material bypasses the scale inhibitor packing 110A from the outside to the inside and enters the internal volume 113 of the inner cylinder.

[0080] A cold mold experiment was conducted using the fouling unit 1 shown in Figure 4A. The fouling unit 1 has a diameter of 600 mm and includes three curved baffles 12 spaced 120 degrees apart. The screen mesh of the curved baffles 12 is 80 mesh. The feed rate was set to 6 tons / hour, the mechanical impurity content was 0.05%, and the mechanical impurity component was non-water-soluble alumina. The experimental results are shown in Table 1.

[0081] Table 1: Filtration efficiency results of descaling unit 1

[0082] In Table 1, "passes through 80 mesh" means that the diameter of the impurity particles cannot pass through an 80-mesh sieve; "mesh" has already been defined above. "passes through 80 mesh" means that the diameter of the impurity particles can pass through an 80-mesh sieve; similarly, "passes through 200 mesh" means that the diameter of the impurity particles can pass through a 200-mesh sieve; and "passes through 300 mesh" means that the diameter of the impurity particles can pass through a 300-mesh sieve. According to the experimental results in Table 1, the total filtration efficiency of the scale-collecting unit 1 of the present invention reaches 78.8%, effectively improving the separation and treatment efficiency of impurities and scale.

[0083] The foregoing description is illustrative in nature and is in no way intended to limit this disclosure, its application, or use. The broad teachings of this disclosure can be implemented in various forms. Therefore, while this disclosure includes specific examples, its true scope should not be so limited, as other modifications will become apparent upon examination of the drawings, description, and appended claims. For example, unless otherwise specifically stated, the size, shape, position, or orientation of various components may be varied as needed and / or desired, provided that such variations do not substantially affect their intended function. Unless otherwise specifically stated, directly connected or contacting components may have intermediate structures arranged between them, provided that such variations do not substantially affect their intended function. Unless otherwise specifically stated, the function of one element may be performed by two elements, and vice versa. The structure and function of one embodiment may be adopted in another embodiment. All advantages are not necessarily present simultaneously in a particular embodiment. Each feature unique compared to the prior art, individually or in combination with other features, should also be considered as the applicant's separate description of further inventions, including structural and / or functional concepts embodied by such features. It should be understood that one or more steps within the method may be performed in different orders (or simultaneously) without altering the principles of this disclosure. Furthermore, while each of the embodiments described above is described as having certain features, any one or more of those features described with reference to any embodiment of this disclosure may be implemented in and / or combined with features of any of other embodiments, even if such combinations are not explicitly described. In other words, the described embodiments are not mutually exclusive, and substitutions of one or more embodiments for each other remain within the scope of this disclosure.

Claims

1. A descaling unit (1), comprising: An inner cylindrical body (11), said inner cylindrical body (11) being formed of a mesh structure, defining a central axis (20) and comprising a cylindrical internal volume (113); and Multiple curved baffles (12) are evenly distributed circumferentially around the inner cylinder (11) and extend outward from the outer periphery of the inner cylinder (11), thereby forming an annular flow channel between adjacent curved baffles (12).

2. The scale buildup unit (1) according to claim 1, wherein, The plurality of curved baffles (12) have an involute shape in a cross section perpendicular to the central axis (20), thereby forming an involute flow channel (120) between adjacent curved baffles (12).

3. The descaling unit (1) according to claim 2, wherein, At least one of the plurality of curved baffles (12) has a mesh structure.

4. The descaling unit (1) according to any one of claims 1 to 3, wherein, The inner cylinder (11) includes an outer ring (112) and an inner ring (111), both of which are mesh structures. The outer ring (112) and the inner ring (111) are spaced apart from each other to form an annular space (110) between the outer ring (112) and the inner ring (111). The annular space (110) is filled with scale inhibitor filler (110A) or folded structure (110B) configured to block the scale particles.

5. The descaling unit (1) according to any one of claims 1 to 3, wherein, The curved baffle has a locally recessed or convex structure in a cross section perpendicular to the central axis (20).

6. The descaling unit (1) according to any one of claims 1 to 3, wherein, The curved baffle plate has a smooth curve or a sawtooth shape (121) in a cross section perpendicular to the central axis (20).

7. The fouling unit (1) according to claim 4, wherein, The curved baffle is formed by a single or multiple layers of mesh structure, and the outer and inner rings of the inner cylinder are formed by a single or multiple layers of mesh structure.

8. The fouling unit (1) according to claim 4, wherein, The radial dimension of the annular space (110) of the inner cylindrical body is at least 50 mm.

9. The descaling unit (1) according to claim 4, wherein, The filling height of the scale inhibitor packing (110A) is lower than the upper edge of the inner cylinder by a predetermined height H to form a top radial overflow channel with a predetermined height H. The top radial overflow channel is configured such that when the scale layer of the accumulated scale particles is flush with the filling height of the scale inhibitor packing in the involute flow channel, the liquid phase material bypasses the scale inhibitor packing from the outside to the inside and enters the internal volume (113) of the inner cylinder.

10. A descaling device, comprising: Scale tray (102); and At least one fouling unit (1) is disposed on the fouling tray (102), each fouling unit (1) being a fouling unit (1) according to any one of claims 1 to 9.

11. A hydrogenation reactor (100) comprising a fouling device according to claim 10, wherein the number of fouling units is plurality of.

12. A method for descaling using the descaling device according to claim 10, comprising the following steps: A. As the liquid level of the liquid material on the scale plate increases, the liquid material generates both circumferential flow along the gradually opening flow channel (120) and radial penetration from the outside to the inside through the curved baffle plate (12) under the static pressure of the accumulated liquid. B. In the circumferential flow of liquid material, scale particles undergo solid-liquid separation through physical sedimentation under the action of gravity and centrifugal force generated by the circumferential flow, and the scale particles settle on the bottom plate. C. During the circulatory flow, due to the sidewall effect, a velocity difference is formed between the liquid phase material near the curved baffle and the liquid phase material in the central region. Scale particles in the lower velocity liquid phase material near the curved baffle are adsorbed at the mesh of the curved baffle. as well as D. The radially permeated liquid material passes through the curved baffle plate from the outside to the inside. During the radial permeation process, the scale particles are filtered through the curved baffle plate in multiple stages.

13. The method for removing scale according to claim 12, wherein, The inner cylinder (11) includes an outer ring (112) and an inner ring (111), both of which are metal mesh structures. The outer ring (112) and the inner ring (111) are spaced apart from each other to form an annular space (110) between the outer ring (112) and the inner ring (111). The annular space (110) is filled with a scale-inhibiting filler (110A) or a folded structure (110B) configured to block the scale particles. The scale buildup method further includes the following steps: E. When the liquid material flows through the inner cylinder, the scale particles in the liquid material are further filtered by the metal mesh structure of the outer ring (112) and inner ring (111) of the inner cylinder, and adsorbed and filtered by scale-inhibiting filler or folded structure.

14. The method for removing scale according to claim 13, wherein, The scale-inhibiting packing (110A) is filled at a height H lower than the upper edge of the inner cylinder to form a top radial overflow channel with a predetermined height H. The scale-accumulation method further includes the following steps: F. When the scale layer of the accumulated scale particles is level with the filling height of the scale inhibitor packing in the gradually opening flow channel, the liquid phase material bypasses the scale inhibitor packing from the outside to the inside and enters the internal volume (113) of the inner cylinder.

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