Fluidized bed reactor
By adopting the finger tube group of the multi -cherished thermal tube structure in the fluidized bed reactor, the problem of being prone to damage and low heat exchange efficiency in the traditional reactor in the traditional reactor, and achieved more efficient heat transfer and stable large -scale large -scale Production.
Patent Information
- Application Number
- CN202411314267.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-20
- Publication Date
- 2025-01-24
AI Technical Summary
In traditional fluidized bed reactors, the weak links of U-shaped tubes and finger tubes are easily damaged by materials, and the heat exchange efficiency is low, which is not conducive to large-scale production.
Adopt a multi -round -back thermal control structure composed of multiple parallel settings, and the sharp corner of the bottom of the tube can avoid damage caused by material washed. The structure of heat pipe beam ensures the overall heat transfer and heat exchange efficiency.
Effectively avoid the problem of damage to the tube group, while ensuring efficient heat exchange efficiency, which is conducive to large -scale production.
Smart Images
Figure CN119346008A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a fluidized bed reactor. Background Art
[0002] Fluidized bed reactor is an important chemical reactor that is easy to produce on a large scale, and is particularly suitable for strong exothermic or endothermic reactions. In order to promptly remove the heat released by the reaction or to promptly heat and maintain the stability of the reaction, the heat exchange tubes in the current domestic fluidized bed reactors are generally U-shaped tubes or finger-shaped tubes.
[0003] In a traditional U-tube fluidized bed reactor, the bend in the tube is a weak link inside the fluidized bed. As the windward side inside the fluidized bed, it will be washed by the silicon powder in the material for a long time, resulting in damage, which is not conducive to large-scale development.
[0004] In the traditional finger-tube fluidized bed reactor, the heat transfer oil only returns once inside the single tube, and the heat transfer amount is small, which will lead to the problem of low heat exchange efficiency and is also not conducive to large-scale development. Summary of the invention
[0005] The object of the present invention is to provide a fluidized bed reactor which can avoid the problem of tube group scouring and damage and ensure the heat exchange efficiency of the tube group, thereby facilitating large-scale production.
[0006] In order to achieve the above object, the technical solution adopted by the present invention is:
[0007] A fluidized bed reactor, comprising a vertical cylinder, a tube group vertically arranged in the cylinder, and a material distributor arranged in the cylinder and below the tube group, wherein the bottom of the cylinder is provided with a material inlet and a catalyst inlet, and the upper part is provided with a product outlet, a heat transfer oil inlet and a heat transfer oil outlet, and the tube group adopts a multi-return heat extraction tube bundle structure composed of a plurality of parallel finger-shaped tubes, each of which comprises an inner tube with openings at both ends and an outer tube sleeved on the outer side of the inner tube, wherein the upper end of the outer tube is open and lower than the upper end of the inner tube, and the lower end of the outer tube is closed;
[0008] An upper tube plate for the upper end of the inner tube to pass through is provided at the upper part of the cylinder, and a supporting tube plate is provided below the upper tube plate and for the upper end of the outer tube to pass through. The heat transfer oil inlet and the heat transfer oil outlet are respectively located above the upper tube plate, and a partition is provided between the two.
[0009] Preferably, a plurality of the tube groups are provided in the cylinder, and a plurality of the finger-shaped tubes in each tube group are evenly spaced and arranged in the cylinder.
[0010] Preferably, the adjacent finger-shaped tubes are arranged in the cylinder in a manner of arranging four vertices of a square.
[0011] Preferably, the cylinder is composed of a feeding section, a reaction section, an expansion section and a thermal oil tank section from bottom to top, and the upper tube sheet and the supporting tube sheet are arranged on the cylinder corresponding to the thermal oil tank section; the material inlet and the catalyst inlet are arranged on the cylinder corresponding to the feeding section, and the finger-shaped tube extends from the thermal oil tank section to the reaction section.
[0012] More preferably, the product outlet is arranged on the cylinder corresponding to the expansion section.
[0013] More preferably, a material return inlet is provided on the cylinder corresponding to the expansion section, and a separator located outside the cylinder is provided between the material return inlet and the product outlet.
[0014] More preferably, the barrel corresponding to the reaction section includes a first tapered portion that gradually widens upward from the feeding section and a first straight barrel portion connecting the first tapered portion and the barrel corresponding to the expansion section.
[0015] More preferably, the cylinder corresponding to the expansion section includes a second conical part, a second straight cylinder part, and a third conical part which are connected in sequence and gradually widen upward from the reaction section, and the third conical part is used to connect the thermal oil tank section.
[0016] Preferably, the fluidized bed reactor further comprises a sleeve which is sleeved on the finger-shaped tube and has conical upper and lower ends, and a connecting rib plate connected between adjacent sleeves.
[0017] More preferably, the upper end of the connecting rib plate is conical or wedge-shaped, and / or the lower end of the connecting rib plate is conical or wedge-shaped.
[0018] Due to the application of the above technical solution, the present invention has the following advantages compared with the prior art: in the fluidized bed reactor of the present invention, the tube group adopts a multi-return heat extraction tube bundle structure composed of multiple parallel finger-shaped tubes, the sharp corners at the bottom of the finger-shaped tubes can avoid damage caused by material scouring, and the multiple finger-shaped tubes in the tube group are connected in sequence through the upper tube plate and the supporting tube plate to form a multi-return heat extraction tube bundle structure, which ensures the overall heat transfer and heat exchange efficiency and is conducive to large-scale production. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] Attached Figure 1 It is a structural schematic diagram of a fluidized bed reactor according to a specific embodiment of the present invention;
[0020] Attached Figure 2 It is a schematic diagram of the connection structure between the tube group, the upper tube sheet and the bearing tube sheet;
[0021] Attached Figure 3 It is a schematic diagram of the arrangement structure of the finger-shaped tubes in the cylinder;
[0022] Attached Figure 4 is a schematic diagram of the structure of the casing;
[0023] Attached Figure 5 Schematic diagram of the structure of the connecting rib plate.
[0024] Among them: 1. Cylinder; 101. Feeding section; 102. Reaction section; 103. Expansion section; 104. Thermal oil tank section; 2. Tube group; 21. Finger-shaped tube; 211. Inner tube; 212. Outer tube; 3. Material distributor; 4. Material inlet; 5. Catalyst inlet; 6. Product outlet; 7. Thermal oil inlet; 8. Thermal oil outlet; 9. Upper tube sheet; 10. Load-bearing tube sheet; 11. Partition plate; 12. Return material inlet; 13. Casing; 14. Connecting rib plate. DETAILED DESCRIPTION
[0025] The technical solution of the present invention is further described below in conjunction with specific embodiments and drawings.
[0026] In the following, only some exemplary embodiments are briefly described. As those skilled in the art will appreciate, the described embodiments may be modified in various ways without departing from the spirit or scope of the embodiments of the present invention. Therefore, the drawings and descriptions are considered to be exemplary and non-restrictive in nature.
[0027] In the description of the embodiments of the present invention, it should be understood that the terms "length", "inside", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the embodiments of the present invention.
[0028] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.
[0029] In the embodiments of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or a communication; it can be a direct connection, or an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present invention can be understood according to specific circumstances.
[0030] In the embodiments of the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes the first feature being directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes the first feature being directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.
[0031] The disclosure below provides many different embodiments or examples to implement different structures of the embodiments of the present invention. In order to simplify the disclosure of the embodiments of the present invention, the parts and settings of specific examples are described below. Of course, they are only examples, and the purpose is not to limit the embodiments of the present invention. In addition, the embodiments of the present invention can repeat reference numbers and / or reference letters in different examples, and this repetition is for the purpose of simplification and clarity, which itself does not indicate the relationship between the various embodiments and / or settings discussed.
[0032] See also Figure 1 As shown, this embodiment provides a fluidized bed reactor, comprising a vertical cylinder 1, a tube group 2 vertically arranged in the cylinder 1, and a material distributor 3 arranged in the cylinder 1 and located below the tube group 2. The tube group 2 adopts a multi-return heat extraction tube bundle structure composed of a plurality of parallel finger-shaped tubes 21, each of which comprises an inner tube 211 with openings at both ends, and an outer tube 212 sleeved on the outer side of the inner tube 211, wherein the upper end of the outer tube 212 is open and lower than the upper end of the inner tube 211, and the lower end of the outer tube 212 is closed and is a downward pointed cone.
[0033] See also Figure 2 As shown, an upper tube plate 9 for the upper end of the inner tube 211 to pass through is provided on the upper portion of the cylinder 1, and a supporting tube plate 10 is provided below the upper tube plate 9 and for the upper end of the outer tube 212 to pass through. The heat transfer oil inlet 7 and the heat transfer oil outlet 8 are respectively located above the upper tube plate 9, and a partition plate 11 is provided between the two.
[0034] This setup has the following advantages:
[0035] The sharp corners at the bottom of the finger-shaped tube 21 can avoid damage caused by repeated scouring of the material transmitted upward during the reaction process, and the service life is relatively long, which is conducive to large-scale production;
[0036] The multiple finger-shaped tubes 21 in the tube group 2 are connected in sequence through the upper tube sheet 9 and the supporting tube sheet 10 to form a multi-return heat extraction tube bundle structure, which ensures the overall heat transfer amount and heat exchange efficiency and is conducive to large-scale production.
[0037] In this embodiment, a plurality of tube groups 2 are provided in the cylinder 1, and a plurality of finger-shaped tubes 21 in each tube group 2 are evenly arranged in the cylinder 1, which is beneficial to uniform heat transfer to the material.
[0038] See also Figure 3 As shown, adjacent finger-shaped tubes 21 are arranged in the cylinder 1 in a square arrangement with four vertices. During the reaction process, the material is not only transported upward, but also has a tendency to move from the center of the circle to the circumference. The traditional triangular arrangement structure will make it difficult to establish a fluidized state, forming a channel flow, which will make the fluidized bed state unstable. In this structure, the square flow channel is interconnected, making it easier to establish a fluidized state. In particular, when the reactant silicon powder is not dry enough, the traditional triangular arrangement structure is more likely to cause adhesion and coking problems. In this embodiment, the pipe spacing is 1.8-2.2 times the outer diameter of the finger-shaped tube 21, which is more conducive to establishing a fluidized state. When the outer diameter and spacing of the finger-shaped tube 21 are the same, the critical fluidization velocity of this structure is 10-15% smaller than that of the triangular arrangement structure.
[0039] See also Figure 1 As shown, the cylinder 1 is composed of a feeding section 101, a reaction section 102, an expansion section 103 and a heat transfer oil tank section 104 from bottom to top. The material inlet 4 and the catalyst inlet 5 are arranged on the cylinder 1 corresponding to the feeding section 101; the product outlet 6 and the return material inlet 12 are arranged on the cylinder 1 corresponding to the expansion section 103; the heat transfer oil inlet 7, the heat transfer oil outlet 8, the upper tube sheet 9 and the supporting tube sheet 10 are arranged on the cylinder 1 corresponding to the heat transfer oil tank section 104; the finger-shaped tube 21 extends downward from the heat transfer oil tank section 104 to the reaction section 102; the return material inlet 12 is located below the product outlet 6, and a separator (not shown in the figure) located outside the cylinder 1 is arranged between the return material inlet 12 and the product outlet 6.
[0040] The barrel 1 corresponding to the reaction section 102 includes a first tapered portion that gradually widens upward from the feeding section 101 and a first straight barrel portion that connects the first tapered portion and the barrel 1 corresponding to the expansion section 103. The barrel 1 corresponding to the expansion section 103 includes a second tapered portion that gradually widens upward from the reaction section 102, a second straight barrel portion, and a third tapered portion that gradually narrows upward, which are connected in sequence, and the third tapered portion is used to connect the thermal oil tank section 104. By setting the expansion section 103, it is possible to avoid excessive discharge per unit time resulting in excessive load on the separator, and by setting the second tapered portion, it is also beneficial to the sedimentation of the reactant silicon powder. In this embodiment, the taper of the second tapered portion is 9-11 degrees.
[0041] See also Figure 4-5 As shown, the fluidized bed reactor further includes a sleeve 13 which is sleeved on the finger-shaped tube 21 and has conical upper and lower ends, and a connecting rib plate 14 connected between adjacent sleeves 13. The upper end of the connecting rib plate 14 is conical or wedge-shaped, and the lower end of the connecting rib plate 14 is conical or wedge-shaped.
[0042] This structural setting can not only reduce the area and resistance of the windward surface at the lower end, thus avoiding blocking the reaction materials being transported upward, but also avoid the accumulation of silicon powder at the upper end, greatly improving the permeability of the fluidized bed reactor, thereby improving the uniformity of the temperature field of the fluidized bed reactor.
[0043] The working principle of the present invention is as follows:
[0044] Since the reaction is an endothermic reaction at the beginning, at the start-up, the heat transfer oil with a certain amount of heat is first introduced into the heat transfer oil tank section 104 from the heat transfer oil inlet 7, enters the inner tube 211 located on the upper tube plate 9, and reaches the end of the inner tube 211, enters the outer tube 212 at the end, flows upward along the outer tube 212 to the position between the upper tube plate 9 and the supporting tube plate 10, and then enters the outer tube 212 of the second finger-shaped tube 21, reaches the end of the outer tube 212, enters the inner tube 211 at the end, flows upward along the inner tube 211 to the upper tube plate 9, and then enters the inner tube 211 of the third finger-shaped tube 21, and the cycle continues, and finally flows upward from the inner tube 211 of the fourth finger-shaped tube 21 through the heat transfer oil outlet 8 to the outside of the fluidized bed. Through this process, the heat transfer oil carrying heat can fully heat the materials in the bed to reach and maintain the reaction temperature in the fluidized bed.
[0045] The reactant raw materials enter the feeding section 101 through the material inlet 4, and enter the bed uniformly through the material distributor 3 for circulating fluidization, and are heated to the reaction temperature by the heat transfer oil. The preheated catalyst and related intermediates enter the fluidized bed through the catalyst inlet 5 through the material distributor 3 and the cone part to realize the reaction. The reactants flow from bottom to top in the fluidized bed, and form a dense phase area at the bottom of the fluidized bed and a dilute phase area in the middle. They pass through the expansion section 103 and enter the separator through the product outlet 6. The separated reactants enter the expansion section 103 again through the return material inlet 12.
[0046] Since the reaction process is an exothermic reaction, when the reaction starts, the temperature in the fluidized bed rises rapidly. In order to maintain the required temperature for the reaction, the heat transfer oil in the tube stops heating and starts to absorb the reaction heat. The heat is carried out of the reactor by the heat transfer oil to achieve a uniform reaction temperature field in the bed.
[0047] The above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with this technology to understand the content of the present invention and implement it. They cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention.
Claims
1. A fluidized bed reactor, comprising a vertical cylinder, a tube group vertically arranged in the cylinder, and a material distributor arranged in the cylinder and below the tube group, wherein the bottom of the cylinder is provided with a material inlet and a catalyst inlet, and the upper part of the cylinder is provided with a product outlet, a heat transfer oil inlet and a heat transfer oil outlet, characterized in that: The tube group adopts a multi-return heat extraction tube bundle structure composed of a plurality of parallel finger-shaped tubes, each of which includes an inner tube with openings at both ends and an outer tube sleeved on the outer side of the inner tube, the upper end of the outer tube is open and lower than the upper end of the inner tube, and the lower end of the outer tube is closed; An upper tube plate for the upper end of the inner tube to pass through is provided at the upper part of the cylinder, and a supporting tube plate is provided below the upper tube plate and for the upper end of the outer tube to pass through. The heat transfer oil inlet and the heat transfer oil outlet are respectively located above the upper tube plate, and a partition is provided between the two.
2. The fluidized bed reactor according to claim 1, characterized in that: A plurality of the tube groups are arranged in the cylinder, and a plurality of the finger-shaped tubes in each tube group are evenly arranged in the cylinder.
3. The fluidized bed reactor according to claim 1, characterized in that: The adjacent finger-shaped tubes are arranged in the cylinder in a manner of arranging four vertices of a square.
4. The fluidized bed reactor according to claim 1, characterized in that: The cylinder is composed of a feeding section, a reaction section, an expansion section and a heat transfer oil tank section from bottom to top. The upper tube sheet and the supporting tube sheet are arranged on the cylinder corresponding to the heat transfer oil tank section; the material inlet and the catalyst inlet are arranged on the cylinder corresponding to the feeding section, and the finger-shaped tube extends from the heat transfer oil tank section to the reaction section.
5. The fluidized bed reactor according to claim 4, characterized in that: The product outlet is arranged on the cylinder corresponding to the expansion section.
6. The fluidized bed reactor according to claim 5, characterized in that: A material return inlet is also provided on the cylinder corresponding to the expansion section, and a separator located outside the cylinder is provided between the material return inlet and the product outlet.
7. The fluidized bed reactor according to claim 4, characterized in that: The cylinder corresponding to the reaction section comprises a first tapered portion which gradually widens upward from the feeding section and a first straight cylinder portion connecting the first tapered portion and the cylinder corresponding to the expansion section.
8. The fluidized bed reactor according to claim 4, characterized in that: The cylinder corresponding to the expansion section includes a second tapered portion, a second straight portion, and a third tapered portion, which are connected in sequence and gradually widen upward from the reaction section. The third tapered portion is used to connect the thermal oil tank section.
9. The fluidized bed reactor according to claim 1, characterized in that: The fluidized bed reactor further comprises a sleeve which is sleeved on the finger-shaped tube and has conical upper and lower ends, and a connecting rib plate connected between adjacent sleeves.
10. The fluidized bed reactor according to claim 9, characterized in that: The upper end of the connecting rib plate is conical or wedge-shaped, and / or the lower end of the connecting rib plate is conical or wedge-shaped.