Quartz fixed bed reactor capable of rapidly replacing catalyst

Abstract

The invention belongs to the technical field of test equipment, and particularly discloses a quartz fixed bed reactor capable of quickly replacing a catalyst. A gas-guide tube is arranged in a quartz reaction tube of the reactor, an upper sealing head, a first sealing plug and a second sealing plug are fixed at the top of the gas-guide tube, the first sealing plug is slidably connected with a fixed support, the quartz reaction tube is fixed in a first groove of the first sealing plug, and the top end of the gas-guide tube is fixed in the first groove and communicated with a first gas inlet connector of the upper sealing head; the fixed bracket is provided with a fixed flange at the lower part of the quartz reaction tube, the quartz reaction tube is sleeved with a gland fixed with the fixed flange in a sealing manner above the quartz disc, and the quartz disc is arranged in a second groove at the top end of the upper flange; the linear driving device body is fixed to the supporting frame, the driving end is fixed to the taper sleeve, a sample tube is fixed in a third groove in the top end of the taper sleeve, and the top end of the taper sleeve abuts against the fixing flange in a sealed mode after the taper sleeve moves upwards in place. The device has the characteristics of simple structure, thermal shock resistance, long service life and convenience in catalyst replacement.

Description

Technical Field

[0001] This invention belongs to the field of experimental equipment technology, specifically relating to a quartz fixed-bed reactor with simple structure, resistance to thermal shock, long service life, convenient catalyst replacement, and rapid catalyst replacement. Background Technology

[0002] In catalytic reaction research and industrial applications, fixed-bed reactors are widely used due to their simple structure, stable operation, and applicability to gas-solid or liquid-solid phase catalytic reactions. Especially in fields such as catalyst performance evaluation, reaction kinetics research, and new material development, quartz fixed-bed reactors are widely used in experimental research on various catalytic reactions, including CO oxidation, VOCs catalytic degradation, and ammonia synthesis, because the quartz material possesses excellent high-temperature resistance, strong chemical inertness, and good light transmittance, making it suitable for high-temperature catalytic reaction scenarios and facilitating observation of the reaction process through visualization.

[0003] Traditional quartz fixed-bed reactors typically employ an integral design, with the catalyst directly filled inside the quartz reaction tube and sealed by upper and lower quartz end caps. An external heating furnace provides the necessary temperature environment for the reaction. However, such reactors have significant drawbacks in practical use: each catalyst replacement requires disassembling the entire reaction system, involving complex operations such as disconnecting gas lines, removing insulation, opening the sealing structure, and removing the quartz reaction tube. This is not only time-consuming and labor-intensive, but also severely reduces experimental efficiency, especially in multi-component comparative experiments. Furthermore, the quartz tube material, due to its brittleness and weak impact resistance, is prone to cracking or seal failure due to mechanical vibration, installation stress, and thermal shock, significantly impacting experimental efficiency and equipment lifespan, and consequently affecting the accuracy of experimental data. In addition, loading and unloading the catalyst under high-temperature conditions poses safety hazards and fails to meet the requirements of rapid sample change functionality in high-throughput screening or multi-component comparative experiments.

[0004] To address the aforementioned issues, existing technologies have proposed several improvements, such as setting up a movable catalyst support platform or employing a dual-chamber structure for partial replacement. However, these solutions generally suffer from poor sealing reliability, insufficient replacement positioning accuracy, and inconvenient interface connections. Especially under conditions involving high temperature, high pressure, or corrosive atmospheres, it is difficult to guarantee long-term airtightness and safety. Furthermore, traditional structures lack effective integration of functions such as front- and back-end gas sampling and online oxygen concentration monitoring, limiting their ability to acquire experimental data and improve process control. In addition, due to the inherent brittleness and low coefficient of thermal expansion of quartz, directly and rigidly connecting the quartz reaction tube to metal components can easily lead to cracking or leakage during heating and cooling due to thermal stress mismatch. Moreover, rigid connections often use a single sealing gasket or a simple compression structure, which is prone to interface leakage under long-term high-temperature and high-pressure conditions, and requires complete disassembly for maintenance, further increasing operational complexity. Therefore, achieving a reliable connection and relative displacement compensation between the quartz and metal components while ensuring a good seal has become a key technical challenge in the design of this type of reactor. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a quartz fixed-bed reactor with a simple structure, resistance to thermal shock, long service life, and convenient catalyst replacement, allowing for rapid catalyst replacement.

[0006] The quartz fixed-bed reactor of the present invention, which allows for rapid catalyst replacement, is implemented as follows: it includes a reactor, a fixed support, a support frame, and a lifting mechanism. The reactor is vertically mounted on the fixed support, the support frame is located at the lower part of the reactor and is fixedly connected to the fixed support, and the lower part of the reactor is fixedly connected to the support frame. The reactor includes a quartz reaction tube and gas guide tubes. The quartz reaction tube is a cylindrical tube with open top and bottom and a quartz disk at the bottom. At least two downward-extending gas guide tubes are arranged inside the quartz reaction tube. The top of the quartz reaction tube is sequentially and fixedly connected with an upper sealing head, a first sealing plug, and a second sealing plug from top to bottom. The outer wall of the first sealing plug is vertically and slidably connected to a fixed support. The top of the quartz reaction tube moves through the second sealing plug and extends to a first groove at the lower end of the first sealing plug for fixation. The top of the gas guide tube is fixed in the first groove at the lower end of the first sealing plug and communicates with the first air inlet on the upper sealing head. The fixed bracket has a fixed flange on the lower side of the quartz reaction tube, and a second groove is provided at the top of the fixed flange. The quartz reaction tube is slidably fitted with a pressure cap that can be detachably and sealed to the fixed flange above the quartz disk. The quartz disk is located in the second groove of the upper flange. The lifting mechanism includes a linear drive device, a conical sleeve, and a base. The linear drive device is located below the quartz reaction tube and its body is fixedly connected to the support frame. The base is a hollow structure with an open top and is vertically positioned between the linear drive device and the quartz reaction tube. The drive end of the linear drive device is fixedly connected to the base and drives the base to move up and down. The conical sleeve is detachably and vertically fixed inside the base and has an outer conical surface at its upper part. A sample tube is vertically sealed on the outer conical surface of the conical sleeve. The sample tube can be moved upward into the quartz reaction tube. After the base moves upward into place, its top end seals against the fixed flange. The side wall of the base is respectively provided with a catalyst rear end sampling interface and a venting interface.

[0007] Furthermore, the top of the base is provided with a stepped hole, the bottom of the cone sleeve is provided with a flange and placed on the shoulder of the stepped hole of the base, a threaded pressure pad that is threaded to the inner wall of the stepped hole is slidably fitted above the flange of the cone sleeve, and a high-temperature resistant second sealing gasket is provided between the threaded pressure pad and the flange of the cone sleeve. When the threaded pressure pad is tightened, the second sealing gasket can be deformed and pressed against the outer cylindrical surface of the cone sleeve. The cone sleeve is provided with a through hole communicating with the sample tube.

[0008] Furthermore, the base has a second stepped hole at the top of the stepped hole, and a high-temperature resistant third sealing gasket located at the top of the threaded pressure gasket and able to abut against the bottom of the fixed flange is provided in the second stepped hole. The side wall of the base is also provided with a rear oxygen sensor interface and a rear temperature measurement interface respectively.

[0009] Furthermore, a high-temperature resistant first sealing gasket is provided between the pressure cap and the quartz disk in the second groove. The pressure cap is threaded to the inner wall of the second groove or bolted to the fixed flange and abuts against the first sealing gasket. A front-end oxygen sensor interface and a catalyst front-end sampling interface are provided on the lower side wall of the quartz reaction tube.

[0010] Furthermore, the support frame includes a first support plate and a second support plate. The first support plate is fixedly connected to a fixed bracket. The second support plate is disposed above the first support plate and fixedly connected by multiple support columns. The body of the linear drive device is fixedly connected to the first support plate. The second support plate is fixedly connected to the bottom end of the fixed flange. The base movably passes through the second support plate.

[0011] Furthermore, multiple limiting posts are spaced apart on the top surface of the second support plate on the outer side of the base, and the limiting posts are detachably fixed to the fixing flange.

[0012] Furthermore, the quartz reaction tube is provided with at least two downward-extending gas guide tubes at intervals inside, and the upper sealing head is provided with at least two first gas inlet ports corresponding to the number of gas guide tubes and connected to them. The quartz reaction tube is also provided with thermocouple guide tubes that pass through the first sealing plug and the second sealing plug in sequence at the top and are fixedly connected to the upper sealing head between the multiple gas guide tubes. The upper sealing head is provided with a thermocouple interface that communicates with the thermocouple guide tube.

[0013] Furthermore, a first rubber ring is fitted onto the gas guide tube at the position between the upper sealing head and the first sealing plug, and the upper sealing head and the first sealing plug are tightly pressed against the first rubber ring from above and below, and the upper sealing head and the first sealing plug are detachably and securely connected; a second rubber ring is fitted onto the top of the quartz reaction tube at the position between the first sealing plug and the second sealing plug, and the first sealing plug and the second sealing plug are tightly pressed against the second rubber ring from above and below, and the first sealing plug and the second sealing plug are detachably and securely connected.

[0014] Furthermore, a slip ring is slidably fitted on the outer wall of the first sealing plug, and the slip ring is fixedly connected to the fixed bracket.

[0015] Furthermore, the quartz reaction tube is vertically arranged inside the heating furnace and extends out of the heating furnace at the top and bottom respectively. The upper sealing head and the first sealing plug are arranged above the top of the heating furnace and are covered with an insulating outer jacket. The second sealing plug extends upward out of the top of the heating furnace and the extended part is covered with an insulating outer jacket. The lower part of the quartz reaction tube extending out of the heating furnace is covered with an insulating outer jacket.

[0016] The present invention has the following beneficial effects: 1. This invention innovatively employs a lifting mechanism and an independent sample tube support design. The catalyst is placed inside the sample tube fitted onto the outer conical surface of the conical sleeve. A linear drive device moves the base and sample tube up and down, completing the loading and unloading of the catalyst without disconnecting the gas pipeline, removing the insulation layer, or disassembling the quartz reaction tube. This completely eliminates the complex operation process of sample changing in traditional integrated reactors. Moreover, a single sample change only requires driving the base down to move the sample tube out and then back up to reset it after replacement. This significantly shortens the sample changing time, thereby greatly improving experimental efficiency, and avoids the mechanical wear caused by frequent disassembly and assembly to the quartz tube. It also avoids the safety hazards of directly loading and unloading the catalyst under high-temperature conditions. It is particularly suitable for high-throughput experimental scenarios such as multi-component comparison and activity decay testing, greatly improving experimental throughput and data acquisition efficiency.

[0017] 2. This invention employs a differentiated sealing design based on the temperature differences in different areas of the reactor: In the high-temperature zone at the bottom of the quartz reaction tube, a pressure cap presses against the first sealing gasket to seal the quartz disc and the fixed flange; the top of the base is sealed against the fixed flange via a third sealing gasket; and the cone sleeve and the base are sealed together by a second sealing gasket and a threaded pressure gasket. All components are made of high-temperature resistant materials suitable for high-temperature environments. In the low-temperature zone at the top of the reactor, a step-by-step sealing process is used, consisting of an upper sealing head, a first sealing plug, and a second sealing plug. Rubber rings are fitted at the joints and tightened with bolts to form an elastic seal. Simultaneously, the second sealing plug isolates the heat source, thereby extending the service life of the seals. Through the synergistic effect of the aforementioned multi-dimensional sealing structure, the problems of poor sealing reliability and easy interface leakage in existing improved solutions are solved, while damage to the sealing surface during disassembly and assembly is reduced, ensuring the airtightness of the equipment during long-term operation under high temperature, high pressure, and corrosive atmospheres.

[0018] 3. To address the issues of high brittleness of quartz material and the mismatch in thermal expansion coefficients between it and metal components, this invention employs a collaborative support mechanism of "bottom pressure + top floating": the bottom of the quartz reaction tube is fixedly supported by a quartz disc, a first sealing gasket, and a pressure cap, while the top is vertically slidably connected to the sliding ring of the fixed bracket via a first sealing plug, thus abandoning the traditional rigid connection mode. This structural design effectively compensates for the difference in thermal expansion between the quartz tube and metal components during heating and cooling, alleviates thermal stress concentration, and prevents the quartz tube from cracking due to thermal shock, installation stress, or mechanical vibration. Simultaneously, it buffers the impact force from the base pressure, thereby significantly improving the equipment's resistance to thermal shock and long-term operational stability, and extending the overall service life of the equipment.

[0019] 4. This invention specifically addresses the shortcomings of traditional reactors in terms of functional integration by constructing a parameter monitoring and sampling system covering both the front and rear ends of the catalyst: The lower sidewall of the quartz reaction tube is equipped with a front-end oxygen sensor interface and a front-end catalyst sampling interface, while the base sidewall features a rear-end oxygen sensor interface, a rear-end catalyst sampling interface, a rear-end temperature measurement interface, and an venting interface. This enables online monitoring of oxygen concentration and sampling and analysis of gas components at both ends during the reaction process. Simultaneously, a thermocouple guide tube is installed inside the quartz reaction tube, which, in conjunction with the thermocouple interface of the sealing head, allows for precise monitoring of the temperature distribution in the reaction zone, providing data support for optimizing reaction conditions. This integrated design not only improves the timeliness and comprehensiveness of experimental data but also reduces the number of external interfaces, lowering the sealing risks caused by excessive interfaces and facilitating in-depth research on catalytic reaction mechanisms and catalyst performance evaluation.

[0020] 5. This invention adopts a modular design, with core components made of conventional materials and using mature processing techniques, such as the quartz reaction tube, support plate, and linear drive device. This not only keeps manufacturing costs under control but also allows for independent disassembly and maintenance of each component, making it easy to replace vulnerable parts such as gaskets and rubber rings, thus reducing equipment maintenance costs. Furthermore, by optimizing the component layout, such as placing the upper sealing head and first sealing plug above the heating furnace and the base drive mechanism below the quartz reaction tube, all sealing structures and drive components avoid the high-temperature core area, ensuring safe equipment operation and reducing the risk of high-temperature operation. This makes it suitable for various complex reaction scenarios involving high temperatures and corrosive atmospheres. In addition, the sample tube of this invention can be adapted to catalysts of different specifications, and the overall structure can be widely used in various gas-solid and liquid-solid phase catalytic reaction experiments such as CO oxidation, VOCs catalytic degradation, and ammonia synthesis, demonstrating strong practicality and versatility. Finally, the structure is simple and rationally laid out, balancing safety, economy, and versatility.

[0021] In summary, this invention achieves several technological breakthroughs through its simple structural design, including rapid sample replacement, high-temperature sealing, thermal stress compensation, and multi-parameter integrated monitoring. It effectively overcomes the shortcomings of traditional quartz fixed-bed reactors, such as cumbersome replacement, easy damage, poor sealing, and limited functionality. It can efficiently and accurately meet the needs of catalyst performance evaluation and reaction kinetics research in scientific research laboratories and has good prospects for widespread application. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the structure of the present invention (excluding the heating furnace and heating jacket); Figure 2 This is an axial sectional view of the present invention; Figure 3 for Figure 2 Enlarged view at point M; Figure 4 for Figure 2 Enlarged view of point N; Figure 5 This is a schematic diagram of the upper sealing head structure of the present invention; Figure 6 This is a schematic diagram of the first sealing plug structure of the present invention; Figure 7 This is a schematic diagram of the second sealing plug structure of the present invention; Figure 8 This is a schematic diagram of the lower connection structure of the quartz reaction tube of the present invention; In the diagram, 1-reactor, 11-quartz reaction tube, 111-quartz disk, 112-front-end oxygen sensor interface, 13-gas guide tube, 14-upper sealing head, 141-first gas inlet, 142-thermocouple interface, 15-first sealing plug, 16-second sealing plug, 17-compression cap, 18-first sealing gasket, 19-thermocouple guide tube, 1A-first rubber ring, 1B-sample tube, 1C-second rubber ring, 21-fixed flange, 22-slip ring, 3 - Support frame, 31- First support plate, 32- Second support plate, 33- Support column, 34- Limiting column, 4- Lifting mechanism, 41- Linear drive device, 42- Conical sleeve, 43- Base, 431- Catalyst rear sampling interface, 432- Vent interface, 433- Rear oxygen sensor interface, 434- Rear temperature measurement interface, 44- Threaded pressure pad, 45- Second sealing gasket, 46- Third sealing gasket, 5- Heating furnace, 6- Heating jacket, 7- Catalyst. Detailed Implementation

[0023] The present invention will be further described below with reference to the accompanying drawings and embodiments, but this does not limit the present invention in any way. Any changes or improvements made based on the teachings of the present invention shall fall within the protection scope of the present invention.

[0024] like Figures 1 to 8 As shown, the present invention provides a quartz fixed-bed reactor with a rapidly replaceable catalyst, comprising a reactor 1, a fixed support, a support frame 3, and a lifting mechanism 4. The reactor 1 is vertically mounted on the fixed support, and the support frame 3 is mounted on the lower part of the reactor 1 and fixedly connected to the fixed support. The lower part of the reactor 1 is fixedly connected to the support frame 3. The reactor 1 includes a quartz reaction tube 11 and a gas guide tube 13. The quartz reaction tube 11 is a cylindrical tube with open top and bottom and a quartz disk 111 at the bottom. At least two downward-extending gas guide tubes 13 are provided inside the quartz reaction tube 11. The top of the quartz reaction tube 11 is sequentially and sealed from top to bottom with an upper sealing head 14, a first sealing plug 15, and a second sealing plug 16. The outer wall of the first sealing plug 15 is vertically and slidably connected to a fixed bracket. The top of the quartz reaction tube 11 moves through the second sealing plug 16 and extends to the first groove at the lower end of the first sealing plug 15 for fixation. The top of the gas guide tube 13 is fixed in the first groove at the lower end of the first sealing plug 15 and communicates with the first air inlet 141 on the upper sealing head 14. The fixed bracket is provided with a fixed flange 21 on the lower side of the quartz reaction tube 11. The top of the fixed flange 21 is provided with a second groove. The quartz reaction tube 11 is slidably fitted with a pressure cap 17 that can be detachably and sealed and fixedly connected (such as screw connection or snap connection) to the fixed flange 21 above the quartz disk 111. The quartz disk 111 is located in the second groove of the upper flange 121. The lifting mechanism 4 includes a linear drive device 41, a conical sleeve 42, and a base 43. The linear drive device 41 is located below the quartz reaction tube 11 and its body is fixedly connected to the support frame 3. The base 43 is a hollow structure with an open top and is vertically arranged between the linear drive device 41 and the quartz reaction tube 11. The driving end of the linear drive device 41 is fixedly connected to the base 43 and drives the base 43 to move up and down. The conical sleeve 42 is detachably and vertically fixed (e.g., connected by screws or clips) inside the base 43 and has an outer conical surface on its upper part. A sample tube 1B is vertically sealed on the outer conical surface of the conical sleeve 42. The sample tube 1B can be moved upward into the quartz reaction tube 11. After the base 43 moves upward into place, its top end seals against the fixed flange 21. The side wall of the base 43 is respectively provided with a catalyst rear end sampling interface 431 and a venting interface 432.

[0025] The upper sealing head 14, the first sealing plug 15, and the second sealing plug 16 are made of stainless steel; the cone sleeve 42 and the sample tube 1B are both made of high-temperature resistant quartz tubes. The upper outer cone surface of the cone sleeve 42 is frosted, and the lower part of the sample tube 1B is provided with a frosted inner cone surface. The outer cone surface of the cone sleeve 42 and the inner cone surface of the sample tube 1B are in sealing contact.

[0026] The linear drive device 41 is a cylinder, a hydraulic cylinder, or a linear motor.

[0027] like Figure 3 As shown, the top of the base 43 is provided with a stepped hole, and the bottom of the cone sleeve 42 is provided with a flange and placed on the shoulder of the stepped hole of the base 43. A threaded pressure pad 44 that is threaded to the inner wall of the stepped hole is slidably fitted above the flange of the cone sleeve 42. A high-temperature resistant second sealing gasket 45 is provided between the threaded pressure pad 44 and the flange of the cone sleeve 42. When the threaded pressure pad 44 is tightened, the second sealing gasket 45 can be deformed and pressed against the outer cylindrical surface of the cone sleeve 42. The cone sleeve 42 is provided with a through hole that communicates with the sample tube 1B.

[0028] The base 43 has a second stepped hole at the top of the stepped hole. A high-temperature resistant third sealing gasket 46 is provided in the second stepped hole, located at the top of the threaded pressure gasket 44 and abutting against the bottom of the fixed flange 21. The side wall of the base 43 is also provided with a rear oxygen sensor interface 433 and a rear temperature measurement interface 434.

[0029] A high-temperature resistant first sealing gasket 18 is provided between the pressure cap 17 and the quartz disk 111 in the second groove. The pressure cap 17 is threaded to the inner wall of the second groove or bolted to the fixed flange 21 and abuts against the first sealing gasket 18. The lower side wall of the quartz reaction tube 11 is provided with a front-end oxygen sensor interface 112 and a catalyst front-end sampling interface. The first sealing gasket 18 serves to seal and buffer the pressure between the quartz reaction tube 11 and the fixed flange 21, preventing direct contact that could damage the quartz reaction tube 11.

[0030] The first sealing gasket 18, the second sealing gasket 45 and the third sealing gasket 46 are graphite gaskets or ceramic fibers, which can withstand high temperature and buffer the stress during the pressing process of the lifting mechanism 4, thereby preventing the quartz reaction tube 11 from breaking.

[0031] like Figure 1 and 2 As shown, the support frame 3 includes a first support plate 31 and a second support plate 32. The first support plate 31 is fixedly connected to a fixed bracket. The second support plate 32 is disposed above the first support plate 31 and is fixedly connected to it by multiple support columns 33. The body of the linear drive device 41 is fixedly connected to the first support plate 31. The second support plate 32 is fixedly connected to the bottom end of the fixed flange 21. The base 43 movably passes through the second support plate 32.

[0032] On the top surface of the second support plate 32, a plurality of limiting posts 34 are provided at intervals on the outer side of the base 43. The limiting posts 34 are detachably fixed to the fixing flange 21 (e.g., screw connection).

[0033] like Figure 2 and 4 As shown, at least two downward-extending gas guide tubes 13 are arranged at intervals inside the quartz reaction tube 11. At least two first gas inlet ports 141 are provided on the upper sealing head 14, corresponding to the number of gas guide tubes 13 and connected to each other. A thermocouple guide tube 19 is also provided inside the quartz reaction tube 11 between the multiple gas guide tubes 13, with its upper part passing through the first sealing plug 15 and the second sealing plug 16 in sequence and fixedly connected to the upper sealing head 14. A thermocouple interface 142 is provided on the upper sealing head 14, which is connected to the thermocouple guide tube 19.

[0034] The gas guide tube 13 is fitted with a first rubber ring 1A at the position between the upper sealing head 14 and the first sealing plug 15. The upper sealing head 14 and the first sealing plug 15 are tightly pressed against the first rubber ring 1A. The upper sealing head 14 and the first sealing plug 15 are detachably and securely connected (e.g., by screws or snap-fits). The top of the quartz reaction tube 11 is fitted with a second rubber ring 1C at the position between the first sealing plug 15 and the second sealing plug 16. The first sealing plug 15 and the second sealing plug 16 are tightly pressed against the second rubber ring 1C. The first sealing plug 15 and the second sealing plug 16 are detachably and securely connected (e.g., by screws or snap-fits).

[0035] A slip ring 22 is slidably sleeved on the outer wall of the first sealing plug 15, and the slip ring 22 is fixedly connected to the fixed bracket.

[0036] like Figure 8 As shown, the quartz reaction tube 11 is vertically arranged inside the heating furnace 5 and extends out of the heating furnace 5 at the top and bottom respectively. The upper sealing head 14 and the first sealing plug 15 are arranged above the top of the heating furnace 5 and are covered with an insulating jacket 6. The second sealing plug 16 extends upward out of the top of the heating furnace 5 and the extended part is covered with an insulating jacket 6. The lower part of the quartz reaction tube 11 extending out of the heating furnace 5 is covered with an insulating jacket 6.

[0037] The working principle and process of this invention: like Figures 1 to 8As shown, during operation, the catalyst 7 is placed inside the sample tube 1B, and then the sample tube 1B containing the catalyst 7 is placed downwards through the frosted inner conical surface onto the frosted outer conical surface of the cone sleeve 42. Subsequently, the flange at the bottom of the cone sleeve 42 is placed on the stepped hole shoulder of the base 43. Then, the second sealing gasket 45 and the threaded pressure gasket 44 are inserted into the cone sleeve 42, and the threaded pressure gasket 44, which is threaded to the inner wall of the stepped hole of the cone sleeve 42, is tightened, so that the second sealing gasket 45 deforms and presses against the outer cylindrical surface of the cone sleeve 42. Then, the cylinder (i.e., the linear drive device 41) is started to drive the base 43 and the sample tube 1B inside it to move upwards until the third sealing gasket 46 set in the second stepped hole of the base 43 presses against the bottom end of the fixed flange 21. At this time, the sample tube 1B containing the catalyst 7 extends into the lower part of the quartz reaction tube 11, completing the addition of the catalyst 7. Afterwards, the heating furnace 5 can be turned on for heating, and inert gas is introduced for exhaust. Once the gas mixing temperature is reached, the preset gas can be introduced into the quartz reaction tube 11 through each gas guide pipe 13 for gas mixing. Then, the heating furnace 5 continues to heat up, and the mixed gas atmosphere reacts with the catalyst 7 in the sample tube 1B after thorough mixing and heating. During the reaction, the front-end oxygen sensor interface 123 and the front-end catalyst sampling interface (not shown in the figure) set on the lower side wall of the quartz reaction tube 11, as well as the rear-end temperature measurement interface 434, the rear-end oxygen sensor interface 433, the rear-end catalyst sampling interface 431, and the venting interface 432 set on the side wall of the base 43, can realize a full-process parameter monitoring and sampling system for the front and rear ends of the catalyst, providing comprehensive data support for the study of catalytic reaction mechanism and performance evaluation.

[0038] After the catalyst 7 has reacted, the heating of the furnace 5 is stopped. After the temperature drops below 200°C, the cylinder (i.e., the linear drive device 41) is started to drive the base 43 and the sample tube 1B inside it to move downwards until the top of the sample tube 1B moves below the second support plate 32. Then the sample tube 1B can be removed directly and the residual catalyst 7 can be cleaned. Next, new catalyst 7 is added into the sample tube 1B and inserted downwards into the frosted outer cone surface of the cone sleeve 42. Then, the cylinder is started as described above to push the base 43 and the sample tube 1B upwards to complete the replacement of the catalyst 7.

[0039] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A quartz fixed-bed reactor with a rapidly replaceable catalyst, comprising a reactor (1), a fixed support, a support frame (3), and a lifting mechanism (4), wherein the reactor (1) is vertically mounted on the fixed support, the support frame (3) is mounted on the lower part of the reactor (1) and fixedly connected to the fixed support, and the lower part of the reactor (1) is fixedly connected to the support frame (3). Its features are: The reactor (1) includes a quartz reaction tube (11) and a gas guide tube (13). The quartz reaction tube (11) is a cylindrical tube with an open top and bottom and a quartz disc (111) is provided at the bottom. At least two downward-extending gas guide tubes (13) are provided inside the quartz reaction tube (11). The top of the quartz reaction tube (11) is sealed and fixedly connected from top to bottom with an upper sealing head (14), a first sealing plug (15) and a second sealing plug (16). The outer wall of the first sealing plug (15) is vertically slidably connected to the fixed bracket. The top of the quartz reaction tube (11) moves through the second sealing plug (16) and extends to the first groove at the lower end of the first sealing plug (15) for fixation. The top of the gas guide tube (13) is fixed in the first groove at the lower end of the first sealing plug (15) and communicates with the first air inlet (141) on the upper sealing head (14). The fixed bracket is provided with a fixed flange (21) on the lower side of the quartz reaction tube (11). The top of the fixed flange (21) is provided with a second groove. The quartz reaction tube (11) is slidably fitted with a pressure cap (17) that can be detachably and sealed and fixedly connected to the fixed flange (21) above the quartz disc (111). The quartz disc (111) is located in the second groove of the upper flange (121). The lifting mechanism (4) includes a linear drive device (41), a conical sleeve (42), and a base (43). The linear drive device (41) is located below the quartz reaction tube (11) and its body is fixedly connected to the support frame (3). The base (43) is a hollow structure with an open top and is vertically located between the linear drive device (41) and the quartz reaction tube (11). The drive end of the linear drive device (41) is fixedly connected to the base (43) and drives the base (43) to move up and down. The conical sleeve (42) is detachably and vertically fixed inside the base (43) and has an outer conical surface on its upper part. A sample tube (1B) is vertically sealed on the outer conical surface of the conical sleeve (42). The sample tube (1B) can be moved upward into the quartz reaction tube (11). After the base (43) moves upward into place, its top end seals against the fixed flange (21). The side wall of the base (43) is respectively provided with a catalyst rear end sampling interface (431) and an venting interface (432).

2. The quartz fixed-bed reactor with rapidly replaceable catalyst according to claim 1, characterized in that: The base (43) has a stepped hole at its top end. The bottom end of the cone sleeve (42) has a flange and is placed on the shoulder of the stepped hole of the base (43). A threaded pressure pad (44) that is threaded to the inner wall of the stepped hole is slidably fitted above the flange of the cone sleeve (42). A high-temperature resistant second sealing gasket (45) is provided between the threaded pressure pad (44) and the flange of the cone sleeve (42). When the threaded pressure pad (44) is tightened, the second sealing gasket (45) can be deformed and pressed against the outer cylindrical surface of the cone sleeve (42). The cone sleeve (42) has a through hole that communicates with the sample tube (1B).

3. The quartz fixed-bed reactor with rapidly replaceable catalyst according to claim 2, characterized in that: The base (43) has a second step hole at the top of the step hole. A high-temperature resistant third sealing gasket (46) is provided in the second step hole, located at the top of the threaded pressure gasket (44) and abutting against the bottom of the fixed flange (21). The side wall of the base (43) is also provided with a rear oxygen sensor interface (433) and a rear temperature measurement interface (434).

4. The quartz fixed-bed reactor with rapidly replaceable catalyst according to claim 1, characterized in that: The second groove contains a high-temperature resistant first sealing gasket (18) between the pressure cap (17) and the quartz disc (111). The pressure cap (17) is threaded to the inner wall of the second groove or bolted to the fixed flange (21) and abuts against the first sealing gasket (18). The lower side wall of the quartz reaction tube (11) is provided with a front-end oxygen sensor interface (112) and a catalyst front-end sampling interface.

5. The quartz fixed-bed reactor with rapidly replaceable catalyst according to claim 1, characterized in that: The support frame (3) includes a first support plate (31) and a second support plate (32). The first support plate (31) is fixedly connected to a fixed bracket. The second support plate (32) is disposed above the first support plate (31) and fixedly connected by multiple support columns (33). The body of the linear drive device (41) is fixedly connected to the first support plate (31). The second support plate (32) is fixedly connected to the bottom end of the fixed flange (21). The base (43) movably passes through the second support plate (32).

6. The quartz fixed-bed reactor with rapidly replaceable catalyst according to claim 5, characterized in that: On the top surface of the second support plate (32), a plurality of limiting posts (34) are provided at intervals on the outside of the base (43), and the limiting posts (34) are detachably fixedly connected to the fixing flange (21).

7. The quartz fixed-bed reactor with rapidly replaceable catalyst according to claim 1, characterized in that: The quartz reaction tube (11) is provided with at least two downward-extending gas guide tubes (13) at intervals inside. The upper sealing head (14) is provided with at least two first air inlets (141) corresponding to the number of gas guide tubes (13) and connected to them. The quartz reaction tube (11) is also provided with thermocouple guide tubes (19) between the multiple gas guide tubes (13), which pass through the first sealing plug (15) and the second sealing plug (16) in sequence at the top and are fixedly connected to the upper sealing head (14). The upper sealing head (14) is provided with a thermocouple interface (142) connected to the thermocouple guide tube (19).

8. The quartz fixed-bed reactor with rapidly replaceable catalyst according to claim 7, characterized in that: The gas guide tube (13) is fitted with a first rubber ring (1A) at the position between the upper sealing head (14) and the first sealing plug (15). The upper sealing head (14) and the first sealing plug (15) are pressed tightly against the first rubber ring (1A) from top to bottom. The upper sealing head (14) and the first sealing plug (15) are detachably and sealed and fixedly connected. The top of the quartz reaction tube (11) is fitted with a second rubber ring (1C) at the position between the first sealing plug (15) and the second sealing plug (16). The first sealing plug (15) and the second sealing plug (16) are pressed tightly against the second rubber ring (1C) from top to bottom. The first sealing plug (15) and the second sealing plug (16) are detachably and sealed and fixedly connected.

9. The quartz fixed-bed reactor with rapidly replaceable catalyst according to any one of claims 1 to 8, characterized in that: A slip ring (22) is slidably sleeved on the outer wall of the first sealing plug (15), and the slip ring (22) is fixedly connected to the fixed bracket.

10. The quartz fixed-bed reactor with rapidly replaceable catalyst according to claim 9, characterized in that: The quartz reaction tube (11) is vertically installed inside the heating furnace (5) and extends out of the heating furnace (5) at the top and bottom respectively. The upper sealing head (14) and the first sealing plug (15) are installed above the top of the heating furnace (5) and are covered with an insulating jacket (6). The second sealing plug (16) extends upward out of the top of the heating furnace (5) and the extended part is covered with an insulating jacket (6). The lower part of the quartz reaction tube (11) extending out of the heating furnace (5) is covered with an insulating jacket (6).

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