An apparatus for the production of synthesis gas from natural gas and carbon dioxide

Abstract

The application discloses a device for preparing synthesis gas by natural gas-carbon dioxide reforming, and relates to the technical field of synthesis gas preparation, comprising a cylinder, a plurality of catalyst fixed beds arranged in series are arranged in the cylinder, a separation cylinder is arranged between two adjacent catalyst fixed beds, and the separation cylinder is fixed to the upper side of the catalyst fixed bed; a replacement assembly is arranged on the cylinder, and the replacement assembly is used for replacing the catalyst fixed bed while keeping the cylinder sealed; the replacement assembly further comprises a frame arranged on the upper and lower ends of the cylinder and a sealing element arranged in the frame; and the catalyst can be replaced on line by arranging the series catalyst fixed beds and the sealing replacement assembly in the cylinder.

Description

Technical Field

[0001] This invention relates to the field of syngas preparation technology, specifically to an apparatus for preparing syngas from natural gas-carbon dioxide reforming. Background Technology

[0002] In the process of producing syngas from natural gas via carbon dioxide reforming, the catalyst fixed bed is the core unit of the reaction. Existing reactors typically seal multiple catalyst fixed beds in series within a single cylindrical chamber, with the reactant gas flowing from bottom to top. This operating mode causes the catalyst bed located downstream (at the bottom) to deactivate first due to prolonged contact with high concentrations of reactant gas. Traditional catalyst replacement methods require interrupting production, depressurizing, cooling, and disassembling the entire unit to remove the deactivated catalyst and refill it. This process is not only inefficient and labor-intensive but also leads to prolonged downtime, resulting in significant economic losses. More importantly, frequent disassembly and reassembly make it difficult to ensure the system's airtightness, allowing air to enter the reaction system, leading to catalyst poisoning or side reactions, severely impacting product quality and production safety. Summary of the Invention

[0003] The purpose of this invention is to provide an apparatus for producing syngas by reforming natural gas with carbon dioxide, so as to solve the problems mentioned in the background art.

[0004] To achieve the above objectives, the present invention provides the following technical solution: an apparatus for producing syngas by natural gas-carbon dioxide reforming, comprising a cylindrical body, wherein a plurality of catalyst fixed beds are arranged in series inside the cylindrical body, and an isolation cylinder is provided between two adjacent catalyst fixed beds, the isolation cylinder being fixed on the upper side of the catalyst fixed beds; The cylinder is equipped with a replacement assembly, which is used to replace the catalyst fixed bed while keeping the cylinder sealed. The replacement assembly also includes frames installed at the upper and lower ends of the cylinder and seals disposed within the frames.

[0005] Preferably, the sealing element includes a sealing frame installed in the frame body, and the sealing frame is provided with a sealing plate 1 and two sealing plates 2 that are arranged opposite each other; the sealing plate 1 and the sealing plate 2 are respectively provided with a driving component 1 and a driving component 2, and the driving component 1 and the driving component 2 are respectively used to drive the sealing plate 1 and the sealing plate 2 to open and close.

[0006] Preferably, the driving component one includes a driving rod fixed on the sealing plate one, and the driving rod drives the sealing plate one to move along the axis of the driving rod by an external linear reciprocating driving component.

[0007] Preferably, the second driving component includes a rotating frame fixedly connected to the second sealing plate. The rotating frame is rotatably connected to the frame, and a motor is fixedly connected to the frame at an axial position of the rotating frame. The output shaft of the motor is fixedly connected to the rotating frame.

[0008] Preferably, a frame is fixedly connected to the side of the sealing plate one away from the sealing plate two, and a column penetrating the sealing plate one is fixedly connected to the frame. The length of the column is equal to the depth of the isolation cylinder, and the column is in clearance fit with the inner wall of the isolation cylinder.

[0009] Preferably, the column is fitted with two semi-sealed cylinders, the semi-sealed cylinders are fixedly connected to the sealing plate, and the isolation cylinder is fitted with the inner wall of the semi-sealed cylinder with a clearance.

[0010] Preferably, the upper frame is longer than the lower frame, and the lower and upper frames are respectively provided with an air inlet and an exhaust outlet; the upper frame has a sealing plate one positioned above the sealing plate two, and the lower frame has a sealing plate one positioned below the sealing plate two; the upper frame has symmetrical sliding grooves on its left and right sides, and an electrically driven lead screw one is installed in the sliding groove, with a drive block sleeved on the lead screw one; the drive block is slidably connected to the sliding groove and threadedly connected to the lead screw one; a motor two is fixedly connected to the drive block, and an electric clamp is provided between the two motor twos, with the output shaft of the motor two fixedly connected to the electric clamp.

[0011] Preferably, an exhaust pipe is fitted onto the column and the exhaust pipe is sealed and fitted to the column and the sealing plate; a motor is fixedly connected to the frame, and a lead screw is fixedly connected to the output shaft of the motor, the lead screw is rotatably connected to the sealing plate and threadedly connected to the exhaust pipe.

[0012] Preferably, the sealing plate one is provided with a four-way air pipe on the side away from the sealing plate two, and an air pump is installed at one port of the four-way air pipe; the column and the sealing plate one are both provided with air ports on the side facing the sealing plate two, and the remaining ports of the four-way air pipe are connected to each air port.

[0013] Preferably, the sealing frames on both the upper and lower sides and the inner wall of the cylinder are fixedly connected with limiting strips, and the catalyst fixed bed is sealed and fitted with the limiting strips; the limiting strip in the lower sealing frame is in contact with the sealing strip inside the cylinder.

[0014] Compared with the prior art, the beneficial effects of the present invention are: This invention, by setting up upper and lower sealing assemblies including sealing plate one and sealing plate two, and cooperating with an electric clamping plate and a screw drive mechanism with clamping, flipping, and lifting functions, allows for the loading of a new catalyst fixed bed from the top and the simultaneous ejection of a deactivated catalyst fixed bed from the bottom under conditions of complete reactor sealing and continuous operation. This process does not require shutdown and depressurization, greatly improving production efficiency and the continuity of plant operation.

[0015] This invention utilizes a dual-structure design combining a column, an isolation cylinder, and a semi-sealed cylinder, along with an active gas replacement and vacuum system formed by an air pump and an exhaust stack. This system enables multiple, multi-stage removal of residual air from the sealed cavity before, during, and after catalyst loading and seal resetting. This fundamentally eliminates the possibility of air entering the main reaction process, effectively protecting catalyst activity, ensuring the purity of the syngas product, and significantly improving the safety and stability of the entire process. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a schematic diagram of the split structure in this invention; Figure 3 This is a cross-sectional view of the frame structure in this invention; Figure 4 This is a cross-sectional view of the sealing frame in this invention; Figure 5 This is a schematic diagram of the disassembled structure of the seal in this invention; Figure 6 This is a schematic diagram of the structure of the sealing plate one in this invention; Figure 7 This is a cross-sectional view of the cylindrical body in this invention; Figure 8 This is a schematic diagram of the structure of the electric clamp in this invention; Figure 9 This is a cross-sectional view of the catalyst fixed bed in this invention; Figure 10 This is a schematic diagram of the feeding process in this invention.

[0017] The attached diagram lists the components represented by each number as follows: 1. Cylinder; 2. Catalyst fixed bed; 3. Isolation cylinder; 4. Frame; 5. Sealing frame; 6. Sealing plate one; 7. Sealing plate two; 8. Drive rod; 9. Rotating frame; 10. Motor one; 11. Frame; 12. Column; 13. Semi-sealed cylinder; 14. Slide groove; 15. Lead screw one; 16. Drive block; 17. Motor two; 18. Electric clamp; 19. Exhaust pipe; 20. Motor three; 21. Lead screw two; 22. Four-way air pipe; 23. Air pump; 24. Air port; 25. Limiting strip. Detailed Implementation

[0018] Please see Figure 1-10The present invention provides a technical solution: a device for preparing syngas by natural gas-carbon dioxide reforming, comprising a cylinder 1, wherein a plurality of catalyst fixed beds 2 are arranged in series inside the cylinder 1, and an isolation cylinder 3 is provided between two adjacent catalyst fixed beds 2, the isolation cylinder 3 being fixed on the upper side of the catalyst fixed bed 2. The cylinder 1 is equipped with a replacement assembly, which is used to replace the catalyst fixed bed 2 while keeping the cylinder 1 sealed. The replacement components also include the frame 4 installed at the upper and lower ends of the cylinder 1 and the seals set inside the frame 4; At work, such as Figure 1 , Figure 2 and Figure 7 As shown, the reforming reaction mixture enters the cylinder 1 through the inlet of the lower frame 4, flows sequentially through multiple series-connected catalyst beds 2, and undergoes a reforming reaction under high temperature and catalyst action to generate syngas, which is finally discharged from the exhaust port of the upper frame 4. Since the airflow direction is from bottom to top, the lowest catalyst bed 2 will be deactivated first. The core of this device lies in the fact that, through the coordinated action of the seals at both ends and the replacement components, the deactivated catalyst bed 2 can be removed from the bottom without shutting down the reactor or depressurizing, while a new catalyst bed 2 is installed from the top, achieving online catalyst replacement.

[0019] As a further embodiment of the present invention, the sealing element includes a sealing frame 5 installed in the frame 4, and a sealing plate 6 and two opposing sealing plates 7 are provided in the sealing frame 5; a driving member 1 and a driving member 2 are respectively provided on the sealing plate 6 and the sealing plate 7, and the driving member 1 and the driving member 2 are respectively used to drive the sealing plate 6 and the sealing plate 7 to open and close. The driving component includes a driving rod 8 fixed on the sealing plate 6. The driving rod 8 drives the sealing plate 6 to move along the axis of the driving rod 8 through an external linear reciprocating driving component. The second driving component includes a rotating frame 9 fixedly connected to the second sealing plate 7. The rotating frame 9 is rotatably connected to the frame 4, and a motor 10 is fixedly connected to the frame 4 at the axial position of the rotating frame 9. The output shaft of the motor 10 is fixedly connected to the rotating frame 9. At work, such as Figure 3 , Figure 4 and Figure 5As shown, under normal operating conditions, sealing plate 6 and the two opposing sealing plates 7 are all in a closed state, forming a sealed barrier for the reaction system. When catalyst replacement is required, the linear reciprocating drive of the upper frame 4 is first activated, driving the upper sealing plate 6 upward via the drive rod 8, causing it to detach from the sealing frame 5. During this process, to balance the pressure, gas can be injected into the sealing frame 5 using the air pump 23 to assist the sealing plate 6 in moving out smoothly. Then, the catalyst bed 2 is inverted and placed inside the sealing frame 5, and the sealing plate 6 is driven to move back into the sealing frame 5 to seal the upper space of the catalyst bed 2. Subsequently, the motor 10 is activated, driving the two sealing plates 7 to open to both sides via the rotating frame 9, thereby forming a channel within the upper frame 4 through which the catalyst bed 2 can pass.

[0020] As a further embodiment of the present invention, a frame 11 is fixedly connected to the side of the sealing plate 6 away from the sealing plate 7, and a column 12 that penetrates the sealing plate 6 is fixedly connected to the frame 11. The length of the column 12 is equal to the depth of the isolation cylinder 3 and the column 12 is in clearance fit with the inner wall of the isolation cylinder 3. Two semi-sealed cylinders 13 are fitted on the column 12. The semi-sealed cylinders 13 are fixedly connected to the sealing plate 7 and the isolation cylinder 3 is fitted with the inner wall of the semi-sealed cylinder 13 with a clearance. At work, such as Figure 5 , Figure 6 and Figure 9 As shown, when the new catalyst fixed bed 2 is placed in the upper sealing frame 5 in an inverted state, the isolation cylinder 3 on it will first insert into the semi-sealed cylinder 13 on the sealing plate 7, which is in a closed state. Subsequently, as the sealing plate 6 moves into the sealing frame 5, the column 12 on it will insert into the interior of the isolation cylinder 3. The double-gap fit structure between the column 12 and the isolation cylinder 3, and between the isolation cylinder 3 and the semi-sealed cylinder 13, can effectively expel the air in the sealed space, creating an oxygen-free or low-oxygen environment for subsequent catalyst replacement and avoiding air contamination of the reaction system; in addition, the air pump 23 can be activated to extract air to the maximum extent, so that a negative pressure state is formed between the sealing plate 6 and the sealing plate 7 in the sealing frame 5.

[0021] As a further embodiment of the present invention, the upper frame 4 is longer than the lower frame 4, and the lower frame 4 and the upper frame 4 are respectively provided with an air inlet and an exhaust outlet; the sealing plate 6 inside the upper frame 4 is positioned above the sealing plate 7, and the sealing plate 6 inside the lower frame 4 is positioned below the sealing plate 7; the upper frame 4 is symmetrically provided with sliding grooves 14 on the left and right sides, and an electrically driven lead screw 15 is installed in the sliding groove 14, and a drive block 16 is sleeved on the lead screw 15. The drive block 16 is slidably connected to the sliding groove 14 and threadedly connected to the lead screw 15; a motor 17 is fixedly connected to the drive block 16, and an electric clamping plate 18 is provided between the two motors 17. The output shaft of the motor 17 is fixedly connected to the electric clamping plate 18. When working, combine Figure 3 , Figure 8 and Figure 10 After the upper sealing plate 7 is opened, the replacement operation enters the core steps. First, the lead screw 15 drives the drive block 16 to move the electric clamping plate 18 upward, precisely clamping the isolation cylinder 3 of the new catalyst fixed bed 2. After clamping, the lead screw 15 reverses its direction, removing the catalyst fixed bed 2 from the sealing frame 5. Then, the motor 17 starts, driving the electric clamping plate 18 to rotate, turning the originally inverted catalyst fixed bed 2 to the upright position. Finally, the lead screw 15 drives again, smoothly inserting the upright catalyst fixed bed 2 into the cylinder 1 from the top. This insertion action pushes the original entire string of catalyst fixed beds 2 in the cylinder 1 down one position, causing the deactivated catalyst fixed bed 2 at the bottom to be squeezed out of the cylinder 1 and fall freely into the lower sealing frame 5 below.

[0022] As a further embodiment of the present invention, an exhaust pipe 19 is sleeved on the column 12 and the exhaust pipe 19 is sealed and fitted to the column 12 and the sealing plate 6; a motor 20 is fixedly connected to the frame 11, and a lead screw 21 is fixedly connected to the output shaft of the motor 20. The lead screw 21 is rotatably connected to the sealing plate 6 and threadedly connected to the exhaust pipe 19. At work, such as Figure 6 As shown, after the new catalyst fixed bed 2 on the upper side is removed by the electric clamp 18, the sealing plate 7 needs to be closed again to restore the seal. Before closing, the motor 20 is started to drive the lead screw 21 to rotate, causing the exhaust pipe 19 to move axially along the column 12 to the farthest end, so that it occupies the internal space of the semi-sealed cylinder 13. When the sealing plate 7 is closed, the inner wall of the semi-sealed cylinder 13 is in contact with the exhaust pipe 19, thereby venting most of the gas in the semi-sealed cylinder 13 into the upper frame 4, effectively reducing the amount of residual gas in the sealed cavity.

[0023] As a further embodiment of the present invention, a four-way air pipe 22 is provided on the side of the sealing plate 1 6 away from the sealing plate 2 7, and an air pump 23 is installed at one of the ports of the four-way air pipe 22; an air port 24 is provided on the side of the column 12 and the sealing plate 1 6 facing the sealing plate 2 7, and the other ports of the four-way air pipe 22 are connected to each air port 24. At work, such as Figure 6As shown, the air pump 23 and the four-way air pipe 22 constitute a pressure regulation system. Throughout the catalyst replacement process, whether it is the movement of sealing plate 6 or the opening and closing of sealing plate 7, the air pump 23 performs precise inflation or deflation operations on the sealed cavity between sealing plate 6 and sealing plate 7 through the air port 24. For example, when sealing plate 6 needs to be detached or reset, inflation can balance the pressure and assist its movement; after sealing plate 7 is closed, deflation can quickly establish a negative pressure, completely expelling residual air, thereby preventing air from entering the main reaction channel to the greatest extent and ensuring the purity of the synthesis gas and the safety of the reaction.

[0024] As a further embodiment of the present invention, the upper and lower sealing frames 5 and the inner wall of the cylinder 1 are all fixedly connected with limiting strips 25, and the catalyst fixed bed 2 is sealed and fitted with the limiting strips 25; the limiting strips 25 in the lower sealing frame 5 are in contact with the sealing strips in the cylinder 1. At work, such as Figure 7 and Figure 9 As shown, the limiting strip 25 plays a crucial guiding and sealing role in the device. Inside the cylinder 1, the limiting strip 25 ensures that the multiple catalyst fixed beds 2 can be precisely aligned and tightly fitted, preventing gas bypass. When replacing the catalyst, the limiting strip 25 in the lower sealing frame 5 aligns with the limiting strip 25 in the cylinder 1, providing precise guidance for the deactivated catalyst fixed bed 2 falling from above, allowing it to accurately fall into the predetermined position of the lower sealing frame 5, facilitating its safe removal via the lower seal.

Claims

1. An apparatus for producing syngas from natural gas-carbon dioxide reforming, comprising a cylindrical body (1), characterized in that: The cylinder (1) is provided with a number of catalyst fixed beds (2) arranged in series, and an isolation cylinder (3) is provided between two adjacent catalyst fixed beds (2). The isolation cylinder (3) is fixed on the upper side of the catalyst fixed bed (2). The cylinder (1) is provided with a replacement assembly, which is used to replace the catalyst fixed bed (2) while keeping the cylinder (1) sealed. The replacement assembly also includes a frame (4) installed at the upper and lower ends of the cylinder (1) and a seal disposed within the frame (4).

2. The apparatus for producing syngas from natural gas via carbon dioxide reforming according to claim 1, characterized in that: The sealing element includes a sealing frame (5) installed in the frame (4), and the sealing frame (5) is provided with a sealing plate (6) and two sealing plates (7) that are arranged opposite each other; the sealing plate (6) and the sealing plate (7) are respectively provided with a driving component (1) and a driving component (2), and the driving component (1) and the driving component (2) are respectively used to drive the sealing plate (6) and the sealing plate (7) to open and close.

3. The apparatus for producing syngas from natural gas via carbon dioxide reforming according to claim 2, characterized in that: The driving component includes a driving rod (8) fixed on the sealing plate (6). The driving rod (8) drives the sealing plate (6) to move along the axis of the driving rod (8) by an external linear reciprocating driving component.

4. The apparatus for producing syngas from natural gas via carbon dioxide reforming according to claim 2, characterized in that: The second driving component includes a rotating frame (9) fixedly connected to the second sealing plate (7). The rotating frame (9) is rotatably connected to the frame (4), and a motor (10) is fixedly connected to the frame (4) at the axial position of the rotating frame (9). The output shaft of the motor (10) is fixedly connected to the rotating frame (9).

5. The apparatus for producing syngas from natural gas via carbon dioxide reforming according to claim 2, characterized in that: A frame (11) is fixedly connected to the side of the sealing plate one (6) away from the sealing plate two (7). A column (12) that passes through the sealing plate one (6) is fixedly connected to the frame (11). The length of the column (12) is equal to the depth of the isolation cylinder (3), and the column (12) is in clearance fit with the inner wall of the isolation cylinder (3).

6. The apparatus for producing syngas from natural gas via carbon dioxide reforming according to claim 5, characterized in that: Two semi-sealed cylinders (13) are fitted on the column (12). The semi-sealed cylinders (13) are fixedly connected to the sealing plate (7) and the isolation cylinder (3) is fitted with the inner wall of the semi-sealed cylinder (13) with a gap.

7. The apparatus for producing syngas from natural gas via carbon dioxide reforming according to claim 2, characterized in that: The upper frame (4) is longer than the lower frame (4), and the lower frame (4) and the upper frame (4) are respectively provided with an air inlet and an exhaust outlet; the sealing plate 1 (6) inside the upper frame (4) is located above the sealing plate 2 (7), and the sealing plate 1 (6) inside the lower frame (4) is located below the sealing plate 2 (7); the upper frame (4) is symmetrically provided with sliding grooves (14) on the left and right sides, and an electrically driven lead screw 1 (15) is installed in the sliding groove (14), and a drive block (16) is sleeved on the lead screw 1 (15). The drive block (16) is slidably connected to the sliding groove (14), and the drive block (16) is threadedly connected to the lead screw 1 (15); a motor 2 (17) is fixedly connected to the drive block (16), and an electric clamp (18) is provided between the two motors 2 (17). The output shaft of the motor 2 (17) is fixedly connected to the electric clamp (18).

8. The apparatus for producing syngas from natural gas via carbon dioxide reforming according to claim 5, characterized in that: An exhaust pipe (19) is fitted on the column (12) and the exhaust pipe (19) is sealed and fitted with the column (12) and the sealing plate (6); a motor (20) is fixedly connected to the frame (11), and a lead screw (21) is fixedly connected to the output shaft of the motor (20). The lead screw (21) is rotatably connected to the sealing plate (6) and threadedly connected to the exhaust pipe (19).

9. The apparatus for producing syngas from natural gas via carbon dioxide reforming according to claim 5, characterized in that: The sealing plate 1 (6) is provided with a four-way air pipe (22) on the side away from the sealing plate 2 (7), and an air pump (23) is installed at one of the ports of the four-way air pipe (22); the column (12) and the sealing plate 1 (6) are provided with air ports (24) on the side facing the sealing plate 2 (7), and the other ports of the four-way air pipe (22) are connected to each air port (24).

10. The apparatus for producing syngas from natural gas via carbon dioxide reforming according to claim 2, characterized in that: Limiting strips (25) are fixedly connected to the sealing frames (5) on both the upper and lower sides and the inner wall of the cylinder (1). The catalyst fixed bed (2) is sealed and fitted with the limiting strips (25). The limiting strips (25) in the lower sealing frame (5) are in contact with the sealing strips in the cylinder (1).

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