Fluidized bed heat exchanger suitable for two-component particles

Abstract

The invention provides a fluidized bed heat exchanger suitable for two-component particles, and relates to the technical field of petrochemical engineering equipment, the fluidized bed heat exchanger comprises a heat exchange tube bundle, the heat exchange tube bundle comprises a flow guide component set and a plurality of heat exchange tubes which are vertically distributed, the flow guide component set is provided with a plurality of flow guide components, and the flow guide components are correspondingly matched with the heat exchange tubes; the heat exchange pipe is sleeved with the flow guide component in an aligned mode, the flow guide component is provided with a flow guide face which is obliquely arranged or vertically arranged relative to the axis of the heat exchange pipe, and a plurality of flow guide channels for gas and solid phases to pass through are formed in the flow guide component; the annular grid is arranged between the gas distributor and the heat exchange tube bundle, the annular grid is provided with a central area and a flow guide area arranged around the central area, the central area is provided with a vertically-through central hole, and the flow guide area is composed of a plurality of deflection baffles arranged in parallel; and the multiple deflection baffles form at least two layers of flowing areas with opposite flowing directions up and down. The fluidized bed heat exchanger is high in heat transfer efficiency.

Description

Technical Field

[0001] This invention relates to petrochemical equipment technology, new material preparation, and energy storage, and particularly to a fluidized bed heat exchanger suitable for two-component particles. Background Technology

[0002] A fluidized bed heat exchanger is a device that combines fluidization technology with a heat transfer process. Its core principle is to suspend solid particles under the influence of a fluid, creating a fluid-like state, and then allow for efficient heat exchange with heat exchange tubes immersed in the bed. Fluidized bed heat exchangers are widely used in catalytic cracking processes.

[0003] With the diversification of feedstocks for catalytic cracking and the increase in the proportion of blended residue oil, the coking yield of heavy oil catalytic cracking is continuously increasing. The heat released by coking in the regenerator exceeds the heat required by the system, necessitating heat recovery operations. Meanwhile, the increasing demand for low-carbon olefins has led to the development of processes such as C4 hydrocarbon catalytic cracking and catalytic cracking gasoline-to-olefins, aiming to expand the feedstock sources for low-carbon olefins and increase olefin production. These processes suffer from low catalyst coking yield and insufficient heat release during regeneration, requiring supplemental heat. On the one hand, to reduce oil surplus and increase low-carbon olefin production; on the other hand, considering that both heavy oil catalytic cracking and light hydrocarbon catalytic cracking units have reaction-regeneration systems, their structures are similar, and they have complementary heat characteristics—the two processes can be coupled to develop catalytic cracking technology that produces more olefins.

[0004] Chinese patent CN114262624A discloses a method and apparatus for fluidized bed catalytic cracking coupled with a two-component particulate catalyst. This fluidized bed-riseer reactor employs two types of catalysts: small-diameter cracking catalyst particles with an average particle size of 50–70 μm and large-diameter pyrolysis catalyst particles with an average particle size of 800–2000 μm. The R0 of both catalysts is... ρdParticles larger than 10 are classified as large-dispersion particles. The lower fluidized bed of the fluidized bed-riseer reactor primarily consists of a catalytic cracking fluidized bed reactor with large-particle-size catalysts, while the upper riser primarily consists of a catalytic cracking riser reactor with small-particle-size catalysts. After the reaction, the majority of the small-particle-size catalyst and a small amount of the large-particle-size catalyst enter the regenerator through the feedstock inclined tube for coke burn-off regeneration. Because the catalytic cracking process produces a high amount of coke, resulting in excess heat, while the light hydrocarbon catalytic cracking process produces less coke and requires heat replenishment, this patented solution couples the two reaction processes into the same system to achieve heat complementarity. Theoretical heat balance calculations show that a 2 million tons / year catalytic cracking process can be coupled with a 720,000 tons / year catalytic cracking process. However, in actual industrial applications, since the planned olefin production of the plant may not always match the production capacity of the existing catalytic cracking unit, excess heat will still exist. Therefore, an external heat exchanger remains an indispensable device for flexibly controlling the heat balance in this process. If the external heat exchanger of catalytic cracking is directly used as the heat exchanger in this fluidized bed-riseer reactor, the presence of large particles will lead to problems such as difficulty in fluidizing large particles, uneven gas distribution in the gas distributor, excessively large bubbles in the dense phase, and short contact time between the catalyst and the heat exchange wall. As a result, the heat transfer effect of the existing external heat exchanger is poor and the heat exchange efficiency is reduced. This poses a serious challenge to the design and use of fluidized bed heat exchangers. Therefore, it is necessary to study the heat transfer characteristics of two-component large-difference particles in the external heat exchanger.

[0005] To improve the heat exchange efficiency of heat exchangers, many external heat exchangers have made improvements to their internal components. These improvements include increasing the heat exchange surface area by adding components, enhancing local disturbances, and improving fluidization quality to increase heat exchange efficiency.

[0006] Finned heat exchange tubes are commonly used in industry. However, during use, the added fins generate excessive local wall effects on the catalyst, resulting in high bed density between fins and easy defluxing of the catalyst between adjacent fins. Furthermore, the large temperature difference between the fins and the base tube leads to the formation and propagation of small cracks under thermal stress. During catalyst flow, longitudinal climbing of the fins along the tube walls also occurs, affecting heat transfer efficiency. To address these issues, CN201229141Y optimizes the commonly used long-finned tubes in industry by changing the fin structure of the heat exchange tube to a finned base and individual fins. CN201229140Y employs a non-uniform height high-low fin configuration, replacing long fins with short fins arranged in a circumferential spiral. These two technologies solve the stress concentration and cracking problems associated with longitudinally long-finned heat exchange tubes, improving heat transfer intensity and extending the service life of the heat exchange tube. CN2457555Y proposes a structure of annular fins concentrically arranged with the steel tube and oblique fins at a certain angle to the steel tube, and twists these fins at a certain angle to enhance the heat transfer process outside the finned tube. CN2515637Y proposes welding nail-head-shaped components to the surface of the heat exchange tube, which not only increases the heat transfer area outside the heat exchange tube, but also improves the heat transfer efficiency through the local turbulence of the nail heads, and weakens the wear and deformation of the heat exchange tube by the catalyst. Moreover, the nail-head tube structure is simple, has good stress distribution at high temperature, is not prone to cracking and deformation, and has a long service life. However, the needle-like structure makes the surface of the heat exchange tube rougher, increasing the wear of the catalyst inside the heat exchanger. CN111854487A uses a regional particle distributor, dilute phase guide vanes, dense phase guide vanes, and dual gas distributor to synergistically enhance the overall heat exchange process of the heat exchanger, increase the particle renewal frequency, and significantly improve the heat exchange efficiency.

[0007] However, existing literature and patents related to fluidized bed external heat exchangers do not address the heat extraction problem for mixed particles with large differences, and existing fluidized bed heat exchangers cannot meet the heat extraction requirements of mixed particles.

[0008] In view of this, based on years of experience in production and design in this and related fields, the inventor has designed a fluidized bed heat exchanger suitable for two-component particles through repeated experiments, in order to solve the problems existing in the prior art. Summary of the Invention

[0009] The purpose of this invention is to provide a fluidized bed heat exchanger suitable for two-component particles, which can meet the heat transfer problem of two-component particles with large differences in density and particle size, and which are prone to poor fluidization quality and stratification.

[0010] To achieve the above objectives, the present invention proposes a fluidized bed heat exchanger suitable for two-component particles, wherein the fluidized bed heat exchanger includes a shell and a component disposed within the shell: A heat exchange tube bundle includes at least one flow guiding member group and multiple vertically distributed heat exchange tubes. The flow guiding member group has multiple flow guiding members, which correspond to and cooperate with the multiple heat exchange tubes. The flow guiding members are aligned and sleeved outside the heat exchange tubes, and the flow guiding members have flow guiding surfaces that are inclined or perpendicular to the axis of the heat exchange tubes. The flow guiding members are provided with multiple flow guiding channels for gas and solid phases to pass through. A gas distributor is disposed below the heat exchange tube bundle, and the gas distributor delivers fluidizing air into the housing; At least one annular grid is disposed between the gas distributor and the heat exchange tube bundle. The outer edge of the annular grid is fixedly connected to the inner wall of the shell. The annular grid has a central region and a flow guiding region arranged around the central region. The central region has a central opening that runs vertically through it. The flow guiding region is composed of a plurality of parallel baffles. The plurality of baffles form at least two layers of flow regions with opposite flow directions.

[0011] Compared with the prior art, the present invention has the following features and advantages: The fluidized bed heat exchanger proposed in this invention, suitable for two-component particles, achieves forced mixing and uniform fluidization of the two-component particles through the synergistic effect of annular grids and flow guiding components. Specifically, the annular grids, through their rectifying effect, further break up the large, non-uniform bubbles generated by the gas distributor jet, thereby optimizing the flow field in the dense phase region of the fluidized bed heat exchanger and mitigating the uneven flow distribution caused by the gas distributor's structure. The flow guiding components construct a grid-like region, causing the catalyst to exhibit a pseudo-crossflow flow state within this region. This enhances the flow state within the shell side of the fluidized bed heat exchanger, inhibits bubble growth, and strengthens the local turbulence of the catalyst. This increases the particle renewal frequency on the surface of the heat exchange tube bundle, thus enhancing the heat exchange process of the fluidized bed heat exchanger. Attached Figure Description

[0012] The accompanying drawings described herein are for illustrative purposes only and are not intended to limit the scope of the invention in any way. Furthermore, the shapes and proportions of the components in the drawings are merely illustrative to aid in understanding the invention and do not specifically limit the shapes and proportions of the components. Those skilled in the art, guided by the teachings of this invention, can select various possible shapes and proportions to implement the invention according to specific circumstances.

[0013] Figure 1 This is a schematic diagram of the structure of the present invention; Figure 2 This is a schematic diagram of the arrangement of the flow guiding component and the heat exchange tube bundle of the present invention; Figure 3This is a top view of an embodiment of the annular grille in Embodiment 1 of the present invention; Figure 4 This is a top view of another embodiment of the annular grille in Embodiment 1 of the present invention; Figure 5 This is a side view of the annular grille in Embodiment 1 of the present invention; Figure 6 This is a schematic diagram of the heat exchange tube bundle arrangement structure in Embodiment 2 of the present invention; Figure 7 This is a front view of the flow guiding component in Embodiment 2 of the present invention; Figure 8 This is a top view of the flow guiding component in Embodiment 2 of the present invention; Figure 9 This is a front view of the flow guiding component in Embodiment 3 of the present invention; Figure 10 This is a top view of the flow guiding component in Embodiment 3 of the present invention; Figure 11 This is a top view of the flow guiding component in Embodiment 4 of the present invention; Figure 12 This is a front view of the flow guiding component in Embodiment 4 of the present invention.

[0014] Explanation of reference numerals in the attached figures

[0015] 100. Fluidized bed heat exchanger; 10. Shell; 11. Catalyst particle inlet; 12. Catalyst particle outlet; 13. Head; 20. Heat exchange tube bundle; 21. Flow guiding component assembly; 22. Heat exchange tube; 221. Water pipe; 222. Steam pipe; 223. Water inlet; 224. Steam outlet; 23. Flow guiding component; 231. Flow guiding surface; 232. Flow guiding channel; 233. Inner ring; 234. Outer ring; 235. Vertical baffle; 236. Baffle plate; 24. Fan-shaped plate; 30. Gas distributor; 40. Annular grid; 41. Central opening; 42. Baffle; 421. Flow guiding blade; 422. Drop hole; 44. Inner tube wall; 43. Outer tube wall; 50. Inclined tube; A. Fluidizing air; B. Catalyst particles to be cooled; C. Cooled catalyst particles; D. Water; E. Water vapor; L. Length; W. Width; α. Angle; T. Height; P. Spacing; r1. Top radius; r2. Bottom radius; d. Horizontal distance; β. Angle with the horizontal direction; H1. Vertical distance; H2. Vertical spacing. Detailed Implementation

[0016] The details of the present invention can be more clearly understood by referring to the accompanying drawings and the description of specific embodiments. However, the specific embodiments of the present invention described herein are for illustrative purposes only and should not be construed as limiting the invention in any way. Under the teachings of this invention, those skilled in the art can conceive of any possible modifications based on the invention, and these should all be considered to fall within the scope of the invention.

[0017] like Figure 1 , Figure 2 As shown, the present invention proposes a fluidized bed heat exchanger 100 suitable for two-component particles, the fluidized bed heat exchanger 100 comprising a shell 10 and a component disposed within the shell 10: The heat exchange tube bundle 20 includes at least one flow guiding member group 21 and multiple vertically distributed heat exchange tubes 22. The flow guiding member group 21 has multiple flow guiding members 23. Each heat exchange tube 22 is sleeved with at least one flow guiding member 23. Each flow guiding member 23 has a flow guiding surface 231 that is inclined or perpendicular to the axis of the heat exchange tube 22. Multiple flow guiding channels 232 for gas and solid phases to pass through are also provided on the flow guiding member 23. Gas distributor 30 is located below heat exchange tube bundle 20 and gas distributor 30 delivers fluidizing air into shell 10; At least one annular grid 40 is disposed between the gas distributor 30 and the heat exchange tube bundle 20. The outer edge of the annular grid 40 is fixedly connected to the inner wall of the shell 10. The annular grid 40 has a central region and a flow guiding region disposed around the central region. The central region has a central opening 41 that runs vertically through it. The flow guiding region is composed of a plurality of parallel baffles 42. The plurality of baffles 42 form at least two layers of flow regions with opposite flow directions.

[0018] The fluidized bed heat exchanger 100 proposed in this invention, suitable for two-component particles, achieves forced mixing and uniform fluidization of the two-component particles through the synergistic effect of the annular grid 40 and the flow guiding component group 21. Specifically, the annular grid 40, through its rectifying effect, further breaks up the large, uneven bubbles generated by the jet from the gas distributor 30, thereby optimizing the flow field in the dense phase region of the fluidized bed heat exchanger and mitigating the uneven flow distribution caused by the structure of the gas distributor 30. The flow guiding component group 21 constructs a grid-like region, causing the catalyst to exhibit a pseudo-crossflow flow state in this region, thus increasing the flow state within the shell side of the fluidized bed heat exchanger 100, suppressing bubble growth, enhancing the local turbulence of the catalyst, increasing the particle renewal frequency on the surface of the heat exchange tube bundle 20, and strengthening the heat exchange process of the fluidized bed heat exchanger 100.

[0019] In this invention, a two-component catalyst (two catalysts) is used in the fluidized bed heat exchanger 100 suitable for two-component particles. The two catalysts include those with an average particle size of 50~70μm and a density of 1440kg / m³. 3 Small-particle-size cracking catalysts, with an average particle size of 800~2000μm and a density of 1161 kg / m³. 3 Large-diameter cracking catalyst particles, both of which have R ρd A value greater than 10 indicates a highly variable particle size.

[0020] The fluidized bed heat exchanger 100 proposed in this invention, suitable for two-component particles, has a central opening 41 in the annular grid 40 that allows a portion of the airflow to carry particles through, forming an upward airflow. This upward airflow not only entrains particles that have settled to the bottom and carries them to the upper heat exchange area, but also reduces the pressure drop caused by the multiple baffles 42. When another portion of the airflow passes through the multiple baffles 42, its direction and velocity are repeatedly changed, allowing the gas and some particles to flow alternately in the guiding area, improving the mixing effect between the particle phase and the gas phase, and improving the uniformity of the raw materials.

[0021] The fluidized bed heat exchanger 100 proposed in this invention is suitable for large-differentiated two-component particles. Each flow guiding component 23 in the flow guiding component group 21 is aligned and sleeved outside the heat exchange tube 22. The flow guiding component 23 can break the gas and particle boundary layer attached to the wall of the heat exchange tube 22, thereby reducing flow bypass and preventing particles from flowing out directly without sufficient heat exchange, effectively improving heat exchange efficiency. The flow guiding surface 231 of each flow guiding component 23 can also force the gas-solid two-phase flow to change direction, increase the turbulence state of the gas-solid two-phase flow, and further suppress bubble growth. At the same time, the flow guiding components 23 in the same flow guiding component group 21 cooperate with each other to guide the gas-solid two-phase flow to be evenly distributed between the heat exchange tubes 22, eliminate channeling and dead zones between the heat exchange tubes 22, and enable all heat exchange tubes 22 to be in a highly efficient working state.

[0022] The fluidized bed heat exchanger 100 proposed in this invention is suitable for two-component particles. One flow guiding component 23 is correspondingly sleeved on one heat exchange tube 22. After the equipment wears out, a single heat exchange tube 22 can be accurately replaced, reducing the maintenance cost and economic loss after the equipment wears out.

[0023] In an optional embodiment of the present invention, within each flow guiding component group 21, each flow guiding component 23 is located on the same horizontal plane or the same inclined plane, thereby forming a uniform, stable and controllable flow field pattern on the entire cross-section of the heat exchange tube bundle 20, effectively eliminating local chaos and mutual interference caused by asynchronous flow guiding.

[0024] In an optional embodiment of the present invention, within each flow guiding component group 21, the flow guiding components 23 on each heat exchange tube 22 can be one layer, two layers, or more.

[0025] In one example, the vertical spacing H2 between adjacent two-layer flow guide members 23 is 40 mm to 200 mm.

[0026] In an optional example of this implementation, if there are two or more layers of flow guiding members 23, the flow guiding channels 232 of each layer of flow guiding members 23 are staggered.

[0027] In an optional example, each layer of flow guide member 23 can be rotated by a rotation angle around the vertical direction to achieve the staggering of the flow guide channels 232 of each layer of flow guide member 23.

[0028] In an optional embodiment of the present invention, a plurality of flow guiding component groups 21 are arranged in the heat exchange tube bundle 20 along the vertical direction, so that the gas and particle boundary layer on the wall of the heat exchange tube 22 can be periodically disrupted, thereby further increasing the heat transfer effect and improving the working efficiency of the heat exchange tube 22.

[0029] In an optional example of this embodiment, the vertical distance H1 between two adjacent flow guide member groups 21 is 50% to 200% of the inner diameter of the housing 10.

[0030] In one optional example of this embodiment, the arrangement position of the flow guiding members 23 on the multiple heat exchange tubes 22 is different from the orientation of the flow guiding surface 231, so that the flow guiding members 23 on the combined multiple heat exchange tubes 22 present a multi-layer horizontal arrangement, and the multiple flow guiding members 23 present a grid-like layout in the shell 10.

[0031] In another optional embodiment of the present invention, the angle α between the flow guiding surface 231 of each flow guiding member 23 on the same heat exchange tube 22 and the axis of the heat exchange tube 22 is different.

[0032] In another optional embodiment of the present invention, the angle α between the flow guiding surface 231 of each flow guiding member 23 on the same heat exchange tube 22 and the axis of the heat exchange tube 22 is the same.

[0033] In an optional embodiment of the present invention, the angle α between the flow guiding surface 231 of the flow guiding member 23 and the axis of the heat exchange tube 22 is 30°~75°.

[0034] In an optional embodiment of the present invention, the flow guiding member 23 is in the shape of a frustum cone, the flow guiding surface 231 is the side wall surface of the flow guiding member 23, and the flow guiding channel 232 is a plurality of through holes formed on the flow guiding member 23.

[0035] In one optional example of this embodiment, the angle α between the guide surface 231 and the axis (centerline) of the heat exchange tube 22 is 30° to 75°.

[0036] In an optional example of this embodiment, the flow guide member 23 is provided with a plurality of through holes, each through hole being opened in the vertical direction.

[0037] Preferably, the flow guiding member 23 is provided with 6 to 12 through holes, and the projected area of ​​each through hole in the vertical direction is 3% to 9% of the projected area of ​​the flow guiding member 23 in the vertical direction.

[0038] In one optional example of this implementation, the through hole is a circular hole, a square hole, a fan-shaped hole, or a triangular hole.

[0039] In an optional example, the total area of ​​all through holes on the flow guide member 23 is 20% to 45% of the total area of ​​the flow guide member 23.

[0040] In an optional example of this embodiment, the flow guide member 23, which is shaped like a frustum cone, has a bottom radius r2 that is 15% to 25% of the inner radius of the shell 10, and a top radius r1 that is the outer diameter of the heat exchange tube 22.

[0041] In an optional example of this embodiment, the thickness of the flow guide 23 is 1.5 mm to 5 mm.

[0042] In another optional embodiment of the present invention, the flow guiding member 23 includes a plurality of fan-shaped plates 24 spaced apart along the circumferential direction of the heat exchange tube 22. One end of the fan-shaped plate 24 is fixedly connected to the outer wall of the heat exchange tube 22, and the other end of the fan-shaped plate 24 extends in a direction away from the heat exchange tube 22. The interval between two adjacent fan-shaped plates 24 forms a flow guiding channel 232.

[0043] In this embodiment, multiple sector plates 24 form a partial frustum structure, the bottom diameter of which is 15% to 25% of the inner diameter of the shell 10, and the top diameter is the outer diameter of the heat exchange tube 22.

[0044] In one optional example of this embodiment, the thickness of the sector plate 24 is 1.5 mm to 5 mm.

[0045] In an optional example of this implementation, the corresponding central angle of the sector plate 24 is 36° to 60° (1 / 10 circle to 1 / 6 circle).

[0046] In an optional example of this embodiment, the flow guiding member 23 includes 3 to 5 fan-shaped plates 24.

[0047] In an optional example of this embodiment, the angle α between the sector plate 24 and the axis of the corresponding heat exchange tube 22 is 30° to 75°.

[0048] In another optional embodiment of the present invention, the flow guiding member 23 is an annular baffle grid structure. The flow guiding member 23 includes an inner ring 233, an outer ring 234, a plurality of vertical partitions 235, and a plurality of baffle plates 236. The outer ring 234 is sleeved outside the inner ring 233 and has an annular gap with the inner ring 233. The plurality of vertical partitions 235 are disposed within the annular gap and are spaced apart along the circumferential direction of the annular gap. One end of each vertical partition 235 is fixedly connected to the inner ring 233, and the other end of the vertical partition 235 is fixedly connected to the outer ring 234. A plurality of baffle plates 236 are disposed between two adjacent vertical partitions 235. The plurality of baffle plates 236 are arranged in parallel and spaced apart. The two ends of each baffle plate 236 are respectively fixedly connected to two vertical partitions 235. The gap between two adjacent baffle plates 236 forms a flow guiding channel 232.

[0049] In one optional example of this embodiment, the inner diameter of the outer ring 234 is 15% to 25% of the inner diameter of the shell 10, and the inner diameter of the inner ring 233 is the same as the outer diameter of the heat exchange tube 22.

[0050] In one optional example of this implementation, the thickness of the outer ring 234 and the thickness of the inner ring 233 are 1.5 mm to 5 mm.

[0051] In one optional example of this implementation, a plurality of vertical partitions 235 divide the annular interval into two or more groups of regions, each group of which is provided with a set of baffles 236 with the same tilt angle.

[0052] In an optional example, the horizontal distance d between two adjacent baffle plates 236 is 0.8% to 2.5% of the inner diameter of the housing 10.

[0053] In an optional example, the length of the baffle plate 236 is less than or equal to half the inner diameter of the outer ring 234, and the height of the baffle plate 236 is 1% to 10% of the inner diameter of the housing 10.

[0054] In an optional example, the baffle plate 236 has multiple through holes.

[0055] Preferably, the opening ratio of the baffle plate 236 is 1~30%.

[0056] In an optional example, the height of the vertical partition 235 is slightly less than or equal to the height of the outer ring 234.

[0057] In an optional embodiment of the present invention, the housing 10 is provided with two or more annular grilles 40, which are arranged sequentially in the vertical direction, and adjacent annular grilles 40 are rotated around the vertical direction by a predetermined angle.

[0058] In an optional example of this implementation, the adjacent ends of two adjacent annular grilles 40 are sealed together, or the adjacent segments of two adjacent annular grilles 40 are sealed against each other.

[0059] In an optional embodiment of the present invention, a plurality of baffles 42 are arranged at equal intervals, each baffle 42 is composed of a plurality of guide vanes 421 arranged vertically, the guide vanes 421 have an angle β with the horizontal direction, the upper and lower adjacent guide vanes 421 are arranged in opposite directions, and each guide vane 421 is provided with at least one drop hole 422.

[0060] In an optional example of this embodiment, the total length of at least one drop hole 422 on the guide vane 421 accounts for 20% to 80% of the length L of the guide vane 421, the total width of at least one drop hole 422 on the guide vane 421 accounts for 50% to 80% of the width W of the guide vane 421, and the total area of ​​at least one drop hole 422 on the guide vane 421 accounts for 40% to 60% of the area of ​​the guide vane 421.

[0061] In one optional example of this embodiment, the shape of at least one drop hole 422 on the guide vane 421 can be a variety of shapes such as triangle, square, circle, ellipse, etc.

[0062] In this embodiment, the size and shape of each drop hole 422 can be the same or different, and the position of the drop holes 422 can be uniform or uneven.

[0063] In one alternative example, the holes 422 are of the same size, and each guide vane 421 has at least one hole 422, which are evenly distributed.

[0064] In another alternative example, when the holes 422 are of different sizes, the multiple holes 422 present an opening pattern arranged in a central ring, with the holes 422 near the inner tube wall 44 of the annular grid (the central area of ​​the external heat exchanger) being larger and the holes 422 near the outer tube wall 43 of the annular grid (the outer heat exchanger shell) being smaller.

[0065] In one optional example of this implementation, multiple guide vanes 421 in two adjacent upper and lower guide regions are connected to each other, and the angle α between each guide vane 421 and the horizontal direction is greater than 30° and less than 75°.

[0066] In one optional example of this embodiment, the height T of the annular grille 40 is 50 mm to 150 mm, the distance P between two adjacent baffles 42 is 40 mm to 150 mm, the horizontal length L of the guide vane 421 is 100 mm to 1000 mm, and the width W of the guide vane 421 is 40 mm to 250 mm.

[0067] In an optional example of this embodiment, the vertical distance between the drop hole 422 of the upper guide vane 421 and the lower guide vane 421 is 40 mm to 200 mm.

[0068] In an optional embodiment of the present invention, the annular grid 40 has an outer pipe wall 43 and an inner pipe wall 44 arranged concentrically, and at least both ends of a portion of the baffle 42 are connected to the outer pipe wall 43, and / or at least both ends of a portion of the baffle 42 are connected to the outer pipe wall 43 and the inner pipe wall 44 respectively.

[0069] In an optional example of this embodiment, the outer tube wall 43 of the annular grille 40 is adapted to the inner wall of the housing 10; the inner diameter of the inner tube wall 44 of the annular grille 40 accounts for 30% to 70% of the inner diameter of the housing 10.

[0070] In an alternative example, the inner tube wall 44 encloses to form a central opening 41.

[0071] In an optional embodiment of the present invention, the upper edge of the annular grid 40 (or multiple annular grids) is 50 mm to 200 mm below the heat exchange tube bundle 20; the lower edge of the annular grid 40 (or multiple annular grids) is 50 mm to 100 mm above the gas distributor 30.

[0072] In an optional embodiment of the present invention, a catalyst particle inlet 11 is provided at the upper part of the shell 10, and a catalyst particle outlet 12 is provided at the bottom of the shell 10.

[0073] In an optional example of this embodiment, the catalyst particle inlet 11 is an inclined tube 50 extending obliquely upward from the side wall of the housing 10.

[0074] In an alternative example, multiple flow guiding member groups 21 are arranged along the length of the heat exchange tube bundle 20 between the inclined tube 50 and the annular grid 40 on the heat exchange tube bundle 20.

[0075] In an optional embodiment of the present invention, the end cap 13 at the top of the housing 10 is detachably configured, and the heat exchange tube bundle 20 passes through the end cap 13 and is fixedly connected thereto, so that the heat exchange tube bundle 20 and the end cap 13 are connected as one unit.

[0076] In one optional example of this implementation, each heat exchange tube 22 is fixed to the end cap 13 using a flange, and the replacement of a single heat exchange tube 22 does not affect each other.

[0077] In an optional embodiment of the present invention, the housing 10 is provided with a fluidizing air inlet that communicates with a gas distributor.

[0078] In an optional embodiment of the present invention, each heat exchange tube 22 includes a water pipe 221 and a steam pipe 222 that is sealed outside the water pipe 221. The top end of each heat exchange tube 22 extends outside the housing 10. The top of the water pipe 221 is provided with a water inlet 223, and the top of the steam pipe 222 is provided with a steam outlet 224.

[0079] In an optional embodiment of the present invention, the inner wall surface of the housing 10 is provided with a heat-insulating and wear-resistant layer.

[0080] Please refer to Figure 1 As shown, the specific usage process of the fluidized bed heat exchanger 100 proposed in this invention is as follows: The catalyst particles B to be cooled enter the shell 10 through the catalyst particle inlet 11. Simultaneously, water D is added to the water pipe 221 of the heat exchange tube 22 through the water inlet 223. Fluidizing air A enters the shell 10 through the fluidizing air inlet and gas distributor 30, and is sprayed towards the upper part of the shell 10. After passing through the annular grid 40, the gas is redistributed. The catalyst particles B to be cooled flow from top to bottom in the shell 10. Under the action of fluidizing air A, the catalyst particles B to be cooled undergo convective heat exchange with the internal heat exchange tube bundle 20. Due to the action of multiple flow guiding components 21, bubble growth is suppressed, ensuring uniform gas-solid distribution. Furthermore, the catalyst particles B to be cooled, in addition to flowing axially in the shell 10, have a radial flow path, thereby increasing the radial backmixing degree and prolonging the residence time of the catalyst to be cooled in the shell 10. Simultaneously, the radial flow of catalyst particles increases the impact force on the surface of the heat exchange tube bundle 20, thereby weakening the influence of the particle retention layer on the surface of the heat exchange tube bundle 20 on heat exchange and enhancing the heat exchange process of the fluidized bed heat exchanger 100. The cooled catalyst particles C after heat exchange flow out through the catalyst particle outlet 12 at the bottom of the shell 10. Water D inside the heat exchange tube 22 is vaporized into water vapor E and discharged through the steam outlet 224.

[0081] This invention, through the rectification and bubble-breaking effects of the annular grid 40, suppresses the generation of large bubbles in the region near the gas distributor 30, thereby improving the fluidization quality of the fluidized bed heat exchanger 100. The presence of multiple flow guiding component groups 21 serves to break up bubbles, increasing the local solids content while enhancing the particle renewal frequency on the surface of the heat exchange tube bundle 20, thus increasing the convective heat transfer coefficient of the fluidized bed heat exchanger 100.

[0082] Please refer to Figures 3 to 12 The present invention will now be described in detail with reference to several specific embodiments.

[0083] Example 1

[0084] like Figures 3 to 5As shown, in this embodiment 1, the annular grid 40, located between the gas distributor 30 and the heat exchange tube bundle 20, is composed of multiple parallel baffles 42. These baffles 42 form at least two layers of flow regions with opposite flow directions. Each baffle 42 has at least one drop hole 422 vertically, allowing the gas and solid phases to flow in a zigzag pattern downwards across at least two flow regions. This breaks up large bubbles generated by the jet from the distribution pipe, resulting in a more uniform bubble distribution and improved local flow conditions. The annular structure ensures that most of the gas and solid phases can flow directly from the center, only breaking up the jet caused by the gas distribution pipe and suppressing the formation of large bubbles, thereby improving local gas-solid flow without affecting the macroscopic gas-solid flow within the equipment. With different hole sizes and arrangements, smaller drop holes near the sidewalls further enhance the flow near the sidewalls, more precisely breaking up long strings of bubbles generated by the biased flow, resulting in more uniform gas distribution and improved gas-solid flow within the bed.

[0085] Example 2

[0086] like Figures 6 to 8 As shown, in this embodiment, the flow guiding member 23 has a partially frustum structure. This flow guiding member 23 is composed of 3 to 5 frustum panels (fan-shaped plates 24) of 1 / 10 to 1 / 6 scale. The angle α between the corresponding conical surface and the centerline of the heat exchange tube 22 is 30° to 75°. The bottom diameter of the flow guiding member 23 is 15% to 25% of the shell-side diameter, the top diameter is the outer diameter of the heat exchange tube 22, and the thickness is 1.5 mm to 5 mm. The flow guiding members 23 generally appear in groups. Flow guiding members 23 in the same horizontal direction or on the same inclined plane are called a group. Each group of flow guiding members 23 has at least one layer. If there are two or more layers of flow guiding members 23, each flow guiding member 23 can rotate around a vertical direction by a rotation angle. The distance between adjacent partially frustum structure flow guiding members 23 is less than 20% of the outer diameter of the heat exchange tube 22. Furthermore, the flow guiding member 23 is tightly connected to the outer diameter of the heat exchange tube 22. The flow guiding component 23 consists of at least one set, or two or more sets of annular grids 40 arranged vertically, with the distance between each set ranging from 50% to 200% of the shell-side diameter. The structure in this embodiment 2 allows the catalyst particles to flow downwards in the shell side, increasing radial crossflow in addition to axial flow. Furthermore, the grid-like structure further breaks up bubbles, inhibiting the growth of large bubbles, while simultaneously enhancing radial backmixing, increasing the contact time between particles and the heat exchange tube wall, and strengthening the heat exchange process.

[0087] Example 3

[0088] like Figures 9 to 10As shown, this embodiment is similar to Embodiment 2 in other aspects, except that the flow guiding member 23 has a frustum structure, with the angle α between the corresponding conical surface and the centerline of the heat exchange tube being 30°~75°. The flow guiding member 23 has 6 to 12 through holes in the vertical direction, each through hole having an area of ​​3%~9% of the annular area of ​​the horizontal projection of the flow guiding member 23 in the vertical direction. The bottom radius r2 of this flow guiding member 23 with the through frustum structure is 15%~25% of the shell-side radius, the top radius r1 is the outer diameter of the heat exchange tube 22, and the thickness is 1.5 mm~5 mm. The grid-like structure further breaks up the bubbles, inhibiting the growth of large bubbles, while simultaneously enhancing radial back-mixing, increasing the contact time between particles and the heat exchange tube wall, and strengthening the heat exchange process.

[0089] Example 4

[0090] like Figures 11 to 12 As shown, this embodiment is similar to Embodiment 2 in other aspects, except that: the flow guiding member 23 has an annular baffle grid structure. The diameter of the outer ring 234 of this annular baffle grid structure is 15% to 25% of the shell diameter, and the diameter of the inner ring 233 is the outer diameter of the heat exchange tube 22. The thickness of the outer ring 234 and the thickness of the inner ring 233 are 1.5 mm to 5 mm. The flow guiding member 23 is divided into two or more groups of regions in the vertical direction by vertical partitions. Each region consists of a set of baffle plates 236 with the same inclination angle and fixedly connected to the vertical partitions. The horizontal distance d between each baffle plate 236 is 0.8% to 2.5% of the shell diameter. The length of the baffle plate 236 is less than or equal to half the diameter of the outer ring 234 of the annular baffle grid structure, and the height of the baffle plate 236 is 1% to 10% of the shell diameter. The opening ratio of the baffle plate 236 is 1% to 30%. The length of the vertical baffle is less than or equal to the diameter of the outer ring 234 of the annular baffle grid structure; the height of the vertical baffle is slightly less than or equal to the vertical height of the inclined baffle plates 236. The inner ring 233 of the annular baffle grid structure is fixedly connected to the heat exchange tube 22. Adjacent annular baffle grid structures in each group fit tightly together vertically. This annular baffle grid structure inhibits bubble growth, further enhances radial backmixing, increases the contact time between particles and the tube wall of the heat exchange tube 22, and strengthens the heat exchange process.

[0091] The detailed explanations of the above embodiments are intended only to explain the present invention so as to facilitate a better understanding of the present invention. However, these descriptions should not be construed as limiting the present invention for any reason. In particular, the various features described in different embodiments can be arbitrarily combined with each other to form other embodiments. Unless there is an explicit description to the contrary, these features should be understood to be applicable to any embodiment, and not limited to the described embodiments.

Claims

1. A fluidized bed heat exchanger suitable for two-component particles, characterized in that, The fluidized bed heat exchanger includes a shell and a component disposed within the shell: A heat exchange tube bundle includes at least one flow guiding member group and multiple vertically distributed heat exchange tubes. The flow guiding member group has multiple flow guiding members, which correspond to and cooperate with the multiple heat exchange tubes. The flow guiding members are aligned and sleeved outside the heat exchange tubes, and the flow guiding members have flow guiding surfaces that are inclined or perpendicular to the axis of the heat exchange tubes. The flow guiding members are provided with multiple flow guiding channels for gas and solid phases to pass through. A gas distributor is disposed below the heat exchange tube bundle, and the gas distributor delivers fluidizing air into the housing; At least one annular grid is disposed between the gas distributor and the heat exchange tube bundle. The outer edge of the annular grid is fixedly connected to the inner wall of the shell. The annular grid has a central region and a flow guiding region arranged around the central region. The central region has a central opening that runs vertically through it. The flow guiding region is composed of a plurality of parallel baffles. The plurality of baffles form at least two layers of flow regions with opposite flow directions.

2. The fluidized bed heat exchanger suitable for two-component particles as described in claim 1, characterized in that, Along the vertical direction, multiple flow guiding component groups are arranged inside the heat exchange tube bundle. In each flow guiding component group, each flow guiding component is located on the same horizontal plane or the same inclined plane. The inclination angle of the flow guiding surface of each flow guiding component on the same heat exchange tube is the same or different.

3. The fluidized bed heat exchanger suitable for two-component particles as described in claim 1, characterized in that, The flow guiding member is shaped like a frustum cone, the flow guiding surface is the side wall surface of the flow guiding member, and the flow guiding channel is a plurality of through holes formed on the flow guiding member.

4. The fluidized bed heat exchanger for two-component particles as described in claim 1, characterized in that, The flow guiding component includes a plurality of sector plates spaced apart along the circumference of the heat exchange tube. The sector plates are fixedly connected to the outer wall of the heat exchange tube, and the interval between two adjacent sector plates forms the flow guiding channel.

5. The fluidized bed heat exchanger for two-component particles as described in claim 1, characterized in that, The flow guiding component is in the form of an annular baffle grid structure, the annular baffle grid structure comprising: The inner ring is fitted over the heat exchange tube; The outer ring is fitted outside the inner ring and has an annular gap with the inner ring; Multiple vertical partitions are spaced apart along the circumference within the annular interval and connect the inner ring and the outer ring; Multiple baffles are arranged in parallel and spaced apart between two adjacent vertical partitions, and the gap between two adjacent baffles forms the flow channel.

6. The fluidized bed heat exchanger for two-component particles as described in claim 1, characterized in that, Multiple flow deflectors are arranged at equal intervals. Each flow deflector is composed of multiple guide vanes arranged vertically. The guide vanes are set at an angle to the horizontal direction. The guide vanes that are adjacent to each other are set in opposite directions. Each guide vane has at least one drop hole.

7. The fluidized bed heat exchanger for two-component particles as described in claim 6, characterized in that, The shape of the drop hole can be triangular, square, circular, or elliptical.

8. The fluidized bed heat exchanger for two-component particles as described in claim 6 or 7, characterized in that, The guide vane is provided with a plurality of drop holes, which are arranged in a central ring, and the inner diameter of each drop hole gradually decreases from the center of the annular grid to the outer edge of the annular grid.

9. The fluidized bed heat exchanger for two-component particles as described in claim 6 or 7, characterized in that, The guide vane is provided with a plurality of drop holes, the plurality of drop holes having the same inner diameter and being evenly distributed on the guide vane.

10. The fluidized bed heat exchanger for two-component particles as described in claim 1, characterized in that, The housing is provided with two or more annular grilles, which are arranged sequentially in the vertical direction, and adjacent annular grilles are rotated around the vertical direction by a predetermined angle.

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