A multi-stage temperature-controlled catalyst basket for a fixed bed reactor

Abstract

This utility model discloses a multi-stage temperature-controlled catalyst basket for a fixed-bed reactor, comprising a multi-stage temperature-controlled catalyst basket body installed inside the reactor shell. An inlet is installed at the top of the reactor shell, and an outlet is also installed on the reactor shell, with a receiving tray connected to the end of the outlet. Ceramic ball plates and stainless steel mesh are provided at the upper and lower parts of the multi-stage temperature-controlled catalyst basket body. This multi-stage temperature-controlled catalyst basket for a fixed-bed reactor achieves uniform distribution of reactants through a combination of a flow equalization plate and an overflow pipe. It utilizes multiple independently temperature-controlled catalyst baskets and an internal heat exchange coil to achieve segmented temperature control of the reaction bed, effectively avoiding localized hot spots and temperature runaway phenomena that are common in fixed-bed reactors. This significantly improves reaction selectivity and catalyst lifespan, and enhances operational convenience and equipment reliability.

Description

Technical Field

[0001] This utility model relates to the field of fixed-bed reactors, specifically a multi-stage temperature-controlled catalyst basket for fixed-bed reactors. Background Technology

[0002] A fixed-bed reactor is a typical multiphase reaction device filled with stationary solid catalyst particles. Its core working principle is as follows: reactants (usually gaseous) continuously pass through a fixed bed of catalyst particles under set temperature and pressure conditions, where a catalytic reaction occurs at the active sites of the catalyst to generate the target product. During this process, there is ample contact between the reaction fluid and the catalyst particles, accompanied by complex mass and heat transfer processes. Finally, the reaction mixture leaves the reaction bed, completing the intended chemical transformation.

[0003] This type of reactor is widely used in petrochemical, coal chemical and fine chemical industries due to its relatively simple structure, high operational stability and ease of continuous and large-scale production. Typical processes include hydrogenation, dehydrogenation, selective oxidation and catalytic reforming.

[0004] As a core piece of equipment in modern petrochemical processes, the performance of fixed-bed reactors is crucial. However, many of the reactions involved (such as deep hydrogenation and partial oxidation) are often accompanied by strong exothermic or endothermic effects. Because the catalyst bed is fixed, its radial and axial heat transfer capacity is usually poor, making it easy to form regions with excessively high ("hot spots") or excessively low ("cold spots") temperatures within the bed. This uneven temperature distribution can cause a series of prominent problems: on the one hand, it may lead to the aggravation of side reactions, reduce reaction selectivity, and affect the yield and purity of the target product; on the other hand, localized high temperatures can accelerate catalyst sintering, carbon deposition, and deactivation, significantly shortening its service life; more seriously, uncontrolled "hot spots" may threaten the safe operation of the reactor and even cause accidents.

[0005] Therefore, how to effectively enhance the heat transfer performance of fixed-bed reactors and suppress or eliminate "hot spots" and "cold spots" in the bed is a key technical problem that needs to be solved to improve reaction efficiency, ensure operational safety, and extend catalyst life. Utility Model Content

[0006] The purpose of this invention is to provide a multi-stage temperature-controlled catalyst basket for fixed-bed reactors to solve the problems mentioned in the background art.

[0007] To achieve the above objectives, a multi-stage temperature-controlled catalyst basket for a fixed-bed reactor is provided, comprising a multi-stage temperature-controlled catalyst basket body, which is installed inside the reactor shell. An inlet is installed at the top of the reactor shell, and an outlet is also installed on the reactor shell, with a receiving tray connected to the end of the outlet. The upper and lower parts of the multi-stage temperature-controlled catalyst basket body are provided with ceramic ball plates and stainless steel mesh. The multi-stage temperature-controlled catalyst basket body includes multiple sets of catalyst baskets, and the interior of each catalyst basket is filled with catalyst.

[0008] Furthermore, a buffer frame is provided at the bottom of the feed inlet, and the bottom of the buffer frame is an isosceles trapezoid. Multiple sets of side buffer openings are equidistantly opened on the outer circumference of the buffer frame, and multiple sets of bottom buffer openings are equidistantly opened at the bottom.

[0009] Furthermore, the bottom buffer opening is circular, the side buffer opening is rectangular, and the buffer frame is positioned directly above the multi-segment temperature-controlled catalyst basket body.

[0010] Furthermore, the multi-segment temperature-controlled catalyst basket body also includes a flow equalization plate, which is circular. The bottom of the flow equalization plate is provided with a base, and multiple overflow pipes are installed at equal intervals on the base. The height of the overflow pipes is less than the depth of the flow equalization plate.

[0011] Furthermore, a sealing disc is installed at the bottom of the base, and multiple sets of sealing ports are equally spaced on the sealing disc, with catalyst baskets inserted inside each of the multiple sets of sealing ports; the flow equalization disc and the sealing disc are both located on the inner wall of the reactor shell.

[0012] Furthermore, a stabilizing frame is fitted around the outer side of multiple sets of catalyst baskets, and multiple sets of perforations are opened on the stabilizing frame. A single catalyst basket is inserted into the inside of the perforation. Multiple sets of stabilizing frames are arranged at equal intervals, and the stabilizing frames are installed on the inner wall of the reactor shell.

[0013] Furthermore, each of the catalyst baskets is equipped with a heat exchange coil, which is spiral-shaped and wraps around the outside of the catalyst.

[0014] Compared with the prior art, the beneficial effects of this utility model are: 1. Through the combined design of "flow equalization plate and overflow pipe", the reactants are more evenly distributed on the cross-section of the bed, effectively eliminating channeling and wall flow effects, ensuring full contact between reactants and catalyst particles, and enhancing the mass transfer process.

[0015] 2. A segmented temperature control mechanism for the reaction bed was constructed by employing multiple independently temperature-controlled catalyst baskets combined with an internal heat exchange coil. This effectively smoothed out axial and radial temperature gradients, completely avoiding the generation of local "hot spots" and the risk of "runaway temperatures," creating an optimal temperature environment for the reaction, thereby significantly improving the selectivity of the target reaction and the product yield.

[0016] 3. By suppressing local overheating of the bed, the rate of catalyst deactivation due to sintering and carbon deposition is fundamentally slowed down, significantly extending its service life, reducing replacement frequency and operating costs, and ensuring the stability and safety of the unit's long-term operation.

[0017] 4. The modular design of the catalyst basket and the built-in stabilizing frame structure make the loading and unloading of catalyst and the inspection and maintenance of reactor internal components simpler and more efficient, greatly improving the maintainability and ease of operation of the equipment. Attached Figure Description

[0018] Figure 1 This is a three-dimensional structural diagram of the present invention; Figure 2 This is a bottom view of the structure of this utility model; Figure 3 This is a schematic diagram of the multi-segment temperature-controlled catalyst basket body of this utility model; Figure 4 This is a schematic diagram of the catalyst basket and its connection structure of the present invention; Figure 5 This is an exploded view of the catalyst basket and its connecting structure of this utility model. Figure 6 This is a schematic diagram of the heat exchange coil structure of this utility model; Figure 7 This is a cross-sectional view of the heat exchange coil structure of this utility model; Figure 8 This is a cross-sectional view of the structural buffer frame of this utility model.

[0019] Numbered in the diagram: 1. Reactor shell; 2. Feed inlet; 21. Buffer frame; 211. Side buffer port; 212. Bottom buffer port; 3. Discharge port; 31. Receiving tray; 4. Ceramic ball plate; 5. Stainless steel mesh; 6. Multi-stage temperature-controlled catalyst basket body; 61. Flow equalization plate; 62. Overflow pipe; 63. Base; 64. Sealing plate; 65. Sealing port; 66. Catalyst basket; 661. Catalyst; 662. Heat exchange coil; 67. Stabilizer; 671. Perforation. Detailed Implementation

[0020] Please see Figures 1-8This utility model provides a multi-stage temperature-controlled catalyst basket for a fixed-bed reactor, including a multi-stage temperature-controlled catalyst basket body 6, which is installed inside the reactor shell 1. The reactor shell 1 has a feed inlet 2 and a discharge outlet 3, with a receiving tray 31 connected to the end of the discharge outlet 3. The upper and lower parts of the multi-stage temperature-controlled catalyst basket body 6 are provided with ceramic ball plates 4 and stainless steel mesh 5. The multi-stage temperature-controlled catalyst basket body 6 includes multiple catalyst baskets 66, and the inside of the catalyst baskets 66 is filled with catalyst 661.

[0021] As a preferred embodiment, the multi-stage temperature-controlled catalyst basket body 6 also includes a flow equalization plate 61, which is circular. The bottom of the flow equalization plate 61 is provided with a base 63, and multiple overflow pipes 62 are installed at equal intervals on the base 63. The height of the overflow pipes 62 is less than the depth of the flow equalization plate 61.

[0022] A sealing plate 64 is installed at the bottom of the base 63, and multiple sets of sealing ports 65 are equally spaced on the sealing plate 64. Catalyst baskets 66 are inserted inside the multiple sets of sealing ports 65. The flow equalization plate 61 and the sealing plate 64 are both located on the inner wall of the reactor shell 1.

[0023] Multiple catalyst baskets 66 are fitted with stabilizers 67 on their outer sides, and multiple perforations 671 are opened on the stabilizers 67. A single catalyst basket 66 is inserted into the inside of the perforations 671. Multiple stabilizers 67 are arranged at equal intervals and are located on the inner wall of the reactor shell 1.

[0024] Multiple catalyst baskets 66 are equipped with heat exchange coils 662 inside, and the heat exchange coils 662 are spiral-shaped and wrap around the outside of the catalyst 661.

[0025] Working principle: The reactants enter the reactor shell 1 through the feed inlet 2, first passing through the bed support structure composed of ceramic ball plates 4 and stainless steel mesh 5, and then reaching the flow equalization plate 61 for initial distribution. When the material in the flow equalization plate 61 exceeds the height of the overflow pipe 62, the material will overflow evenly and enter the multiple sets of parallel catalyst baskets 66 below through the sealing port 65 on the sealing plate 64, making full contact with the catalyst 661 in the catalyst basket 66 and reacting. During this process, the spiral heat exchange coil 662 wrapped around the catalyst 661 controls the reaction temperature of each section of the catalyst bed through the heat exchange medium. After the reaction is completed, the product is finally collected through the bottom ceramic ball plates 4 and stainless steel mesh 5, and enters the receiving plate 31 through the discharge port 3 to complete the discharge. Throughout the process, multiple sets of stabilizers 67 provide radial positioning and stable support for the catalyst basket 66 array through their perforations 671.

[0026] The uniform distribution of reactants is achieved by combining the equalization plate 61 and the overflow pipe 62. The segmented temperature control of the reaction bed is achieved by using multiple independently temperature-controlled catalyst baskets 66 and internal heat exchange coils 662, which effectively avoids the local hot spots and runaway temperature phenomenon that are prone to occur in fixed bed reactors, significantly improving reaction selectivity and catalyst life. At the same time, the modular design of the catalyst basket 66 and the structure of the stabilizer 67 facilitate assembly, disassembly and maintenance, improving the convenience of operation and the reliability of equipment operation. By introducing and draining liquid into multiple sets of heat exchange coils 662 through multiple inlets and outlets set outside the reactor shell 1, heat transfer oil or steam at different temperatures can be introduced into the heat exchange structure of different areas, realizing independent temperature control of each bed area; effectively eliminating bed "hot spots", improving reaction selectivity and product yield; extending the service life of catalyst 661 and reducing the frequency of shutdown and replacement.

[0027] By setting spiral heat exchange coils 662 inside multiple catalyst baskets 66 and tightly wrapping them around the outside of catalyst 661, independent and rapid control of the reaction temperature of each section of the catalyst bed can be achieved. This can efficiently and promptly remove the heat released by strongly exothermic reactions or replenish the heat required for endothermic reactions, thereby fundamentally and effectively suppressing the formation of bed "hot spots" or "cold spots" caused by uneven reaction heat effects. At the same time, combined with the uniform distribution system formed by the flow equalization plate 61 and the overflow pipe 62, as well as the buffer frame 21 at the bottom of the feed inlet 2, the uniformity of the flow rate and concentration of the reactants when entering each catalyst basket 66 is ensured, avoiding local overheating or overcooling caused by uneven fluid distribution. The comprehensive temperature control and distribution design significantly improves the selectivity of the reaction process, greatly extends the service life of catalyst 661, and fundamentally enhances the safety and stability of fixed-bed reactor operation.

[0028] As a preferred embodiment, the bottom of the feed inlet 2 is provided with a buffer frame 21, and the bottom of the buffer frame 21 is an isosceles trapezoid. Multiple sets of side buffer openings 211 are equally spaced on the outer circumference of the buffer frame 21, and multiple sets of bottom buffer openings 212 are equally spaced at the bottom.

[0029] The bottom buffer port 212 is circular, the side buffer port 211 is rectangular, and the buffer frame 21 is located directly above the multi-segment temperature-controlled catalyst basket body 6.

[0030] like Figure 8As shown: The isosceles trapezoidal buffer frame 21 at the bottom of the feed inlet 2 and the multiple sets of rectangular side buffer ports 211 equidistantly opened on its outer circumference, together with the multiple sets of circular bottom buffer ports 212 at the bottom, constitute a highly efficient feed buffer and distribution system. This system can significantly reduce the initial kinetic energy of the feed gas, effectively avoid the direct impact of the gas on the catalyst bed in the multi-stage temperature-controlled catalyst basket body 6 below, thereby preventing the wear, pulverization and channeling of catalyst particles 661. Through multi-directional and multi-angle outlets, the material can be pre-dispersed, laying a good foundation for a more uniform distribution in the subsequent flow equalization plate 61. Ultimately, this ensures the uniformity and stability of the flow field in the entire reactor, improves reaction efficiency and catalyst lifespan.

Claims

1. A multi-stage temperature-controlled catalyst basket for a fixed-bed reactor, comprising a multi-stage temperature-controlled catalyst basket body (6), characterized in that: The multi-stage temperature-controlled catalyst basket body (6) is installed inside the reactor shell (1), and the reactor shell (1) is equipped with a feed inlet (2) at the top. At the same time, the reactor shell (1) is also equipped with a discharge outlet (3), and the end of the discharge outlet (3) is connected to a receiving tray (31). The upper and lower parts of the multi-stage temperature-controlled catalyst basket body (6) are provided with ceramic ball plates (4) and stainless steel mesh (5). The multi-stage temperature-controlled catalyst basket body (6) includes multiple catalyst baskets (66), and the inside of the catalyst basket (66) is filled with catalyst (661).

2. The multi-stage temperature-controlled catalyst basket for a fixed-bed reactor according to claim 1, characterized in that: The feed inlet (2) is provided with a buffer frame (21) at the bottom, and the bottom of the buffer frame (21) is an isosceles trapezoid. Multiple sets of side buffer openings (211) are equidistantly opened on the outer circumference of the buffer frame (21), and multiple sets of bottom buffer openings (212) are equidistantly opened at the bottom.

3. A multi-stage temperature-controlled catalyst basket for a fixed-bed reactor according to claim 2, characterized in that: The bottom buffer opening (212) is circular, the side buffer opening (211) is rectangular, and the buffer frame (21) is located directly above the multi-segment temperature-controlled catalyst basket body (6).

4. A multi-stage temperature-controlled catalyst basket for a fixed-bed reactor according to claim 1, characterized in that: The multi-segment temperature-controlled catalyst basket body (6) also includes a flow equalization plate (61), and the flow equalization plate (61) is circular. The bottom of the flow equalization plate (61) is provided with a base (63), and multiple overflow pipes (62) are installed at equal intervals on the base (63). The height of the overflow pipes (62) is less than the depth of the flow equalization plate (61).

5. A multi-stage temperature-controlled catalyst basket for a fixed-bed reactor according to claim 4, characterized in that: The base (63) is equipped with a sealing plate (64) at the bottom, and multiple sets of sealing ports (65) are equally spaced on the sealing plate (64). Catalyst baskets (66) are inserted inside the multiple sets of sealing ports (65); the flow equalization plate (61) and the sealing plate (64) are both located on the inner wall of the reactor shell (1).

6. A multi-stage temperature-controlled catalyst basket for a fixed-bed reactor according to claim 5, characterized in that: A stabilizing frame (67) is fitted around the outside of multiple catalyst baskets (66), and multiple perforations (671) are opened on the stabilizing frame (67). A single catalyst basket (66) is inserted into the inside of the perforation (671). Multiple sets of stabilizing frames (67) are arranged at equal intervals, and the stabilizing frame (67) is located on the inner wall of the reactor shell (1).

7. A multi-stage temperature-controlled catalyst basket for a fixed-bed reactor according to claim 6, characterized in that: Multiple catalyst baskets (66) are provided with heat exchange coils (662) inside, and the heat exchange coils (662) are spiral-shaped, and the heat exchange coils (662) are wrapped around the outside of the catalyst (661).

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