Gas uniform distribution mixer

Abstract

The invention relates to the technical field of gas mixing equipment, in particular to a gas uniform distribution mixer which is connected to a gas inlet pipe opening of an esterification tower and comprises a barrel, a supporting frame, a balance plate, a rectifier and a distributor, and the supporting frame is located in the barrel and comprises a front end connecting part, a shaft pipe and a rear end connecting part; the shaft tube is rotationally connected with the front end connecting part and the rear end connecting part, the shaft tube is communicated with the rear end connecting part, the rear end connecting part is communicated with an oxygen inlet outside the cylinder body, a balance plate and a plurality of distributors are connected to the shaft tube, air holes are uniformly distributed in the balance plate, the distributors are arrayed in the circumferential direction of the shaft tube, and the air holes are communicated with the air holes. Air outlet holes are formed in each distributor at intervals, the air outlet holes incline towards the rear end connecting part, and a rectifier connected to the inner wall of the cylinder body is arranged between the balance plate and the distributors. According to the invention, oxygen and NO gas are fully mixed and dispersed, local high temperature is avoided, and meanwhile, oxygen can be quickly consumed and is prevented from being doped into subsequent processes.

Description

Technical Field

[0001] The invention relates to the technical field of gas mixing equipment, and in particular to a gas uniform distribution mixer. Background Art

[0002] In the production process of ethylene glycol from synthesis gas, the catalytic coupling of carbon monoxide (CO) to prepare dimethyl oxalate (DMO) mainly involves two steps: (1) CO reacts with nitrite (MN) to produce DMO and nitric oxide (NO) under the action of supported palladium-alumina (Pd-A12O3) catalyst; (2) NO generated by the coupling reaction reacts with methanol and O2 to produce MN, which is called regeneration reaction. The specific reaction formula is: 2CH3ONO+2CO=(COOCH3)2+2NO; 2NO+2CH3OH+1 / 2O2=2CH3ONO+H2O; The MN regeneration reaction requires O2, and the reaction product is the flammable and explosive intermediate MN. Due to strong heat release and O2 penetration, the operational safety and flexibility of the MN regeneration reactor and the CO coupling reactor are greatly reduced. It was found that the increase in O2 flow caused the local O2 concentration at the oxygenation port in the esterification tower to be too high, and the reaction was violent. The excessive oxygen concentration also caused uneven mixing of the components in the gas, and there was a possibility that O2 would enter the CO coupling reactor. At the same time, Zhang Xu also emphasized in "Research Progress on Oxalate Preparation by CO Gas Phase Coupling", Industrial Catalysis, Vol. 21, No. 8, August 2013, that O2 entering the CO coupling reactor reaction system will deactivate the catalyst and affect the continuity of the reaction.

[0003] Therefore, how to mix the components in the reaction system evenly becomes a key issue that needs to be solved in the MN regeneration reaction.

[0004] The patent document with application number 202321218424.6 discloses a reduced-diameter gas uniform distribution mixer, including a cylinder, an oxygen distributor, a cyclone and an oxygen pipeline. The cylinder has a NO gas inlet and a mixing chamber. The oxygen distributor is fixedly connected to the cylinder and is located in the mixing chamber. There are multiple cyclones, each of which is connected to the cylinder respectively. The oxygen distributor of the above structure can only release oxygen at a fixed position, which has a certain effect on preventing ablation of internal parts, but still cannot promote uniform mixing of each combination. The oxygen concentration is high near the center of the pipeline and low near the pipe wall. There is still a risk that the oxygen cannot be fully mixed and consumed, and it cannot meet production needs. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides a gas uniform mixer, the purpose of which is to fully mix and disperse oxygen and NO gas to avoid local high temperature, and at the same time enable oxygen to be consumed quickly to avoid being mixed into subsequent processes.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is: A gas uniform mixer is connected to the air inlet of the esterification tower, comprising a cylinder, a support frame, a balance plate, a rectifier and a distributor; The support frame is located inside the cylinder, and includes a front connecting portion and a rear connecting portion connected to the inner wall of the cylinder, and an axial tube rotatably connected between the front connecting portion and the rear connecting portion, one end of the axial tube is closed, and the other end is connected to the rear connecting portion, and the rear connecting portion is connected to the oxygen inlet outside the cylinder, and a balance plate and a plurality of distributors are provided on the axial tube; A plurality of the distributors are arranged in an array along the circumference of the shaft tube, and each of the distributors is provided with an air outlet hole connected to the shaft tube at intervals, and the air outlet hole is inclined toward the rear end connection portion; The balancing plate is evenly distributed with air holes, and a rectifier connected to the inner wall of the cylinder is arranged between the balancing plate and the distributor.

[0007] The present invention uses an axial tube with a rotating function, on which a distributor is provided, and a balance plate and a rectifier are provided in the upstream direction of the distributor. The pressure imbalance in the cross-sectional direction of the pipeline caused by the setting of a support frame and the original valves and turning components on the pipeline is first eliminated, and then the airflow in the NO gas (mainly N2 and NO) cylinder is adjusted to a smooth airflow, so that the airflow of the NO gas forms a fully developed flow field, and then the distributor is used to evenly distribute oxygen in the cylinder, so that oxygen is distributed at any position along the radial direction of the cylinder. Compared with the prior art, the present invention uses a distributor to adjust the concentrated oxygen release to evenly distribute the oxygen in the circumferential direction, so that the oxygen and NO gas are fully contacted and mixed. Unlike the prior art, oxygen is not only supplied to a fixed position, so that the oxygen concentration in a certain position is too high. Therefore, the present invention can fully mix and disperse oxygen and NO gas, avoid local high temperature, and at the same time enable oxygen to be consumed quickly.

[0008] Furthermore, the front end connecting part includes a first bearing, a first connecting ring and a plurality of connecting plates, the outer ends of the plurality of connecting plates are connected to the inner wall of the cylinder body, and the inner ends are connected to the first connecting ring located on the central axis of the cylinder body, and the first connecting ring is connected to the shaft tube via the first bearing; the rear end connecting part includes a second bearing, a second connecting ring and a plurality of connecting tubes, the outer ends of the connecting tubes are connected to the inner wall of the cylinder body, and the inner ends are connected to the second connecting ring located on the central axis of the cylinder body, and the second connecting ring is connected to the shaft tube via the second bearing, there are two second bearings, a cavity is formed between the two second bearings, an air inlet connected to the cavity is provided on the shaft tube, and one of the plurality of connecting tubes passes through the cylinder body and is connected to the oxygen inlet outside the cylinder body.

[0009] The front end connection part of the present invention is only used to maintain the center position of the shaft tube, so the width direction of the connecting plate is arranged along the length direction of the cylinder, which is beneficial to reducing the pressure drop and reducing the area of ​​turbulent pressure imbalance. The present invention arranges the oxygen supply pipeline in the downstream direction of the distributor.

[0010] Furthermore, the distributor includes an air guide pipe and an air guide plate, one end of the air guide pipe is connected to the shaft pipe, and the other end is in sliding contact with the inner wall of the cylinder, an inclined air guide plate is provided on the air guide pipe, and one end of the air outlet is connected to the air guide pipe and the other end passes through the air guide plate.

[0011] The air guide plate can not only make the distributor and the shaft tube rotate when the air flows through, but also make the air flow form low pressure on its surface, so as to promote the rapid dispersion and mixing of oxygen discharged from the air outlet in the NO gas.

[0012] Furthermore, the end of the air guide plate connected to the air guide pipe is thicker and the end away from the air guide pipe is thinner. The end of the air guide plate away from the air guide pipe is provided with a serrated edge, and the air outlet corresponds to the tip of the edge of the air guide plate.

[0013] The air guide plate with a gradual thickness makes the turbulent state of the air flow located at the tail of the air guide plate, avoiding the increase of vibration of the air guide plate due to the vortex at the front end of the air guide plate, reducing noise and extending the maintenance interval. The serrated edge can make the air flow form a redistribution effect at the edge of the air guide plate, and the air flow at the tip position is dispersed to both sides of the tip, so that the oxygen discharged from the air outlet forms a good surface distribution effect at the edge of the air guide plate and forms a vortex turbulence state here, rather than just a linear distribution, which is more conducive to the dispersion of oxygen in NO gas.

[0014] Furthermore, a spoiler column corresponding to the end of the air outlet is provided on the air guide plate.

[0015] The spoiler column is used to increase the spoiler effect. When the airflow passes through two adjacent columns, a vortex will be formed, which will eliminate the laminar state of the airflow that is about to leave the surface of the air guide plate, form turbulence, promote the mixing of oxygen and NO gas, and make the oxygen discharged from the air outlet undergo turbulent mixing, which can also reduce the surface temperature of the air guide plate.

[0016] Furthermore, a spoiler connected to the inner wall of the cylinder is provided between the distributor and the rear end connection portion. The spoiler is composed of a plurality of spoilers arranged in sequence, and two adjacent spoilers are coaxial and in opposite directions.

[0017] The spoiler is used to make the airflow form a multi-channel cutting state, increase the airflow disturbance, make the airflow field chaotic, promote the turbulent state of the gas, and make the airflow mixed evenly.

[0018] Furthermore, the spoiler comprises an outer ring, connecting rods and spoiler rods, a plurality of connecting rods are distributed in a ring array inside the outer ring, and a spoiler rod is provided between two adjacent connecting rods.

[0019] Furthermore, the rectifier includes a sleeve, a partition plate and a spacer plate, the partition plate divides the space inside the sleeve into a plurality of fan-shaped cavities, the spacer plate divides the space inside the fan-shaped cavity into a plurality of triangular cavities, and the cross-sectional area of ​​the plurality of triangular cavities along the central axis of the cylinder to the outer wall of the cylinder gradually decreases.

[0020] The shape and structure of the rectifier are specifically disclosed. The rectifier of the present invention can make the airflow run in a straight line, eliminate the turbulent state, and avoid generating a large concentration difference when distributing oxygen.

[0021] Furthermore, the length of the rectifier 4 is 1-1.5 times the diameter of the cylinder 1 .

[0022] Furthermore, the aspect ratio of the cylinder is 4-6, and flanges are provided at both ends of the outer wall of the cylinder.

[0023] Compared with the prior art, the present invention can achieve the effect of uniform oxygen distribution with a shorter length, is directly connected to the air inlet of the esterification tower, does not rely on long pipelines for mixing, and is more in line with production transformation needs.

[0024] Beneficial Effects The present invention can fully mix and disperse oxygen and NO gas to avoid local high temperature, and at the same time, the oxygen can be consumed quickly to avoid being mixed into subsequent processes.

[0025] The present invention first eliminates the pressure imbalance in the cross-sectional direction of the pipeline caused by the setting of the support frame and the original valves and turning parts on the pipeline, and then adjusts the NO gas (mainly N2 and NO) in the cylinder to a smooth airflow, so that the airflow of the NO gas forms a fully developed flow field, and then uses a distributor to evenly distribute oxygen in the cylinder, so that oxygen is distributed at any position along the radial direction of the cylinder. Compared with the prior art, the present invention distributes oxygen more evenly, so that oxygen and NO gas are in full contact.

[0026] The air guide plate of the present invention can not only make the distributor and the shaft tube rotate when the air flow passes through, but also make the air flow form low pressure on its surface, thereby promoting the rapid dispersion and mixing of oxygen discharged from the air outlet in the NO gas. The serrated edge and spoiler column of the air guide plate also have the effect of promoting the mixing of gas components.

[0027] The invention can realize the distribution and mixing of oxygen and NO gas in a relatively short length, does not require a relatively long pipeline, and will not generate excessive pressure drop. It has a simple structure and is easy to manufacture, and is suitable for the transformation needs of the existing synthesis gas to ethylene glycol. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a structural schematic diagram of the present invention (partial cross-section of the cylinder); Figure 2 is a sectional top view of the present invention; Figure 3 It is a left side view of the rectifier of the present invention; Figure 4 It is a left side view of the spoiler of the present invention; Figure 5 yes Figure 2 AA section view; Figure 6 yes Figure 5 BB section view.

[0029] The numbers in the accompanying drawings are: 1, cylinder; 2, support frame; 3, balance plate; 4, rectifier; 5, distributor; 6, flange; 7, front end connection; 8, shaft tube; 9, rear end connection; 10, connecting plate; 11, first connecting ring; 12, first bearing; 13, connecting pipe; 14, second connecting ring; 15, second bearing; 16, air inlet; 17, oxygen inlet; 18, air vent; 19, air outlet; 20, air guide tube; 21, air guide plate; 22, spoiler column; 23, spoiler; 24, outer ring; 25, connecting rod; 26, spoiler rod; 27, sleeve; 28, partition plate; 29, spacer plate. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments.

[0031] like Figure 1 and Figure 2 As shown, a gas uniform mixer is connected to the air inlet of the esterification tower, and the rated oxygen flow rate of the esterification tower is 2500m 3 / h, the outer diameter of the NO gas supply pipeline is 630mm, wherein the NO gas contains about 85% N2, which is used to dilute NO and oxygen to avoid excessive reaction, including a cylinder 1, a support frame 2, a balance plate 3, a rectifier 4 and a distributor 5.

[0032] The outer diameter of the cylinder 1 is 630 mm and the length is 3200 mm. The aspect ratio of the cylinder 1 is 4-6. Flanges 6 are provided at both ends of the outer wall of the cylinder 1. The support frame 2 is located inside the cylinder 1. The support frame 2 includes a front end connection part 7, an axis tube 8 and a rear end connection part 9. The front end connection part 7 includes a plurality of connection plates 10. The outer ends of the plurality of connection plates 10 are connected to the inner wall of the cylinder 1 and the inner ends are connected to a first connection ring 11 located on the central axis of the cylinder 1. The first connection ring 11 is connected to the axis tube 8 via a first bearing 12. The front end connection part 7 is used to maintain the center position of the axis tube 8. The width direction of the connection plate 10 is arranged along the airflow direction. The rear end connection part 9 includes a plurality of connection pipes 13. The outer ends of the connection pipes 13 are connected to the inner wall of the cylinder 1 and the inner ends are connected to the first connection ring 11 located on the central axis of the cylinder 1. A second connecting ring 14 located on the central axis of the cylinder 1 is connected, and the second connecting ring 14 is connected to the shaft tube 8 via a second bearing 15. There are two second bearings 15, and there is a spacing between the two second bearings 15 to form a ventilated cavity. The shaft tube 8 is provided with an air inlet 16 located between the two second bearings 15, and the air inlet 16 is connected to the connecting pipe 13 via the cavity. One of the multiple connecting pipes 13 passes through the cylinder 1 and is connected to an oxygen inlet 17 outside the cylinder 1. The rear end connecting part 9 is used to supply oxygen and has a certain turbulent effect. The shaft tube 8 is rotatably connected to the front end connecting part 7 and the rear end connecting part 9. The front end of the shaft tube 8 is closed, and the shaft tube 8 is connected to the rear end connecting part 9. The shaft tube 8 is connected to a balance plate 3 and multiple distributors 5.

[0033] The present invention uses an axial tube 8 with a rotating function, on which a distributor 5 is provided, and a balancing plate 3 and a rectifier 4 are provided in the upstream direction of the distributor 5. The pressure imbalance in the cross-sectional direction of the pipeline caused by the setting of the support frame 2 and the original valves and turning components on the pipeline is first eliminated, and then the airflow in the NO gas (mainly N2 and NO) cylinder 1 is adjusted to a smooth airflow, and then oxygen distribution is performed.

[0034] The balance plate 3 is a perforated plate with a thickness of 50 mm to 100 mm. The balance plate 3 is evenly distributed with air holes 18. The perforated plate can eliminate the pressure deviation caused by valves and turning points on the pipeline to a certain extent, so that the airflow in the pipeline tends to develop fully.

[0035] A plurality of the distributors 5 are arrayed circumferentially along the shaft tube 8, and each of the distributors 5 is provided with air outlet holes 19 at intervals, and the air outlet holes 19 are inclined toward the rear end connection part 9. The inclined air outlet holes 19 can cause the distributor 5 to rotate. The distributor 5 is connected to the shaft tube 8, and the shaft tube 8 is rotatably connected to the front end connection part 7 and the rear end connection part 9, driving the balance plate 3 to rotate.

[0036] A rectifier 4 connected to the inner wall of the cylinder 1 is provided between the balance plate 3 and the distributor 5. The rectifier 4 is as shown in FIG. Figure 3 and Figure 4As shown, the function of the rectifier 4 is to adjust the airflow in the cylinder 1 into a smooth airflow, so that the airflow of the NO gas forms a fully developed flow field, and cooperates with the distributor 5 to make the oxygen evenly distributed in the cylinder 1, so that the oxygen and NO gas can be fully mixed and dispersed, avoiding local high temperature, and at the same time allowing the oxygen to be consumed quickly.

[0037] like Figure 5 and Figure 6 As shown, the distributor 5 includes an air guide pipe 20 and an air guide plate 21, one end of the air guide pipe 20 is connected to the shaft pipe 8, and the other end is in sliding contact with the inner wall of the cylinder 1, the air guide pipe 20 is provided with an inclined air guide plate 21, the air outlet hole 19 passes through the air guide plate 21, the end of the air guide plate 21 connected to the air guide pipe 20 has a large thickness, and the end away from the air guide pipe 20 has a small thickness, the end of the air guide pipe 20 away from the air guide pipe 20 is provided with a serrated edge, the air outlet 19 corresponds to the tip of the edge of the air guide plate 21, and the air guide plate 21 is provided with a spoiler column 22 located at the end of the air outlet hole 19.

[0038] The air guide plate 21 causes the distributor 5 and the shaft tube 8 to rotate when the air flows through, and cooperates with the air outlet 19 to make the distributor 5 and the shaft tube 8 rotate more smoothly, thereby promoting the rapid dispersion and mixing of the oxygen discharged from the air outlet 19 in the NO gas. The thickness of the air guide plate 21 and the air guide tube 20 is in a gradual state, which can reduce the vibration caused by wind resistance and reduce the possibility of fatigue fracture of the distributor 5 and the shaft tube 8. At the same time, the serrated edge can cause the airflow to form a redistribution effect at the edge of the air guide plate 21, thereby improving the mixing effect of the various components in the gas and being more conducive to the dispersion of oxygen in the NO gas.

[0039] A spoiler connected to the inner wall of the cylinder 1 is provided between the distributor 5 and the rear end connecting part 9. The spoiler is composed of a plurality of spoilers 23 arranged in sequence. The spoiler 23 includes an outer ring 24, a connecting rod 25 and a spoiler rod 26. The plurality of connecting rods 25 are distributed in a circular array in the outer ring 24. A spoiler rod 26 is provided between two adjacent connecting rods 25. Two adjacent spoilers 23 are staggered with each other. The shape and structure of the spoiler 23 are specifically disclosed. The spoiler 23 of the present invention has a large flow cross-section without increasing the pressure drop too much. The spoiler is used to make the airflow form a multi-channel cutting state, increase the airflow disturbance, make the airflow flow field chaotic, promote the turbulent state of the gas, and make the airflow mixed evenly. In addition, the rod has higher strength and high temperature resistance than the thin-sheet blades of the cyclone.

[0040] The length of the rectifier 4 is 800mm-1200mm, which is 1-1.5 times the diameter of the cylinder 1. The rectifier 4 includes a sleeve 27, a partition plate 28 and a spacer plate 29. The partition plate 28 divides the space in the sleeve 27 into a plurality of fan-shaped cavities, and the spacer plate 29 divides the space in the fan-shaped cavity into a plurality of triangular cavities. The cross-sectional area of ​​the plurality of triangular cavities gradually decreases from the central axis of the cylinder 1 to the inner wall of the cylinder 1.

[0041] It should be understood that the specific embodiments described herein are only used to explain the present invention, and are not used to limit the present invention.

Claims

1. A gas uniform mixer connected to the air inlet of an esterification tower, characterized in that: It comprises a cylinder (1), a support frame (2), a balance plate (3), a rectifier (4) and a distributor (5); The support frame (2) is located inside the cylinder (1), and comprises a front connecting portion (7) and a rear connecting portion (9) connected to the inner wall of the cylinder (1), and an axial tube (8) rotatably connected between the front connecting portion (7) and the rear connecting portion (9), one end of the axial tube (8) is closed, and the other end is connected to the rear connecting portion (9), the rear connecting portion (9) is connected to the oxygen inlet (17) outside the cylinder (1), and a balance plate (3) and a plurality of distributors (5) are provided on the axial tube (8); A plurality of the distributors (5) are arranged in an array along the circumference of the shaft tube (8), and each of the distributors (5) is provided with an air outlet hole (19) communicating with the shaft tube (8) at intervals, and the air outlet hole (19) is inclined toward the rear end connection portion (9); The balancing plate (3) is evenly distributed with air holes (18), and a rectifier (4) connected to the inner wall of the cylinder (1) is provided between the balancing plate (3) and the distributor (5).

2. The gas uniform mixer according to claim 1, characterized in that: The front connecting portion (7) comprises a first bearing (12), a first connecting ring (11) and a plurality of connecting plates (10); the outer ends of the plurality of connecting plates (10) are connected to the inner wall of the cylinder (1) and the inner ends are connected to the first connecting ring (11) located on the central axis of the cylinder (1); the first connecting ring (11) is connected to the shaft tube (8) via the first bearing (12); the rear connecting portion (9) comprises a second bearing (15), a second connecting ring (14) and a plurality of connecting pipes (13); the outer ends of the connecting pipes (13) are connected to the inner wall of the cylinder (1) and the inner ends are connected to the second connecting ring (14) located on the central axis of the cylinder (1); the second connecting ring (14) is connected to the shaft tube (8) via the second bearing (15); there are two second bearings (15), a cavity is formed between the two second bearings (15), the shaft tube (8) is provided with an air inlet (16) connected to the cavity; one of the plurality of connecting pipes (13) passes through the cylinder (1) and is connected to an oxygen inlet (17) outside the cylinder (1).

3. The gas uniform mixer according to claim 1, characterized in that: The distributor (5) comprises an air guide pipe (20) and an air guide plate (21); one end of the air guide pipe (20) is connected to the shaft pipe (8), and the other end is in sliding contact with the inner wall of the cylinder (1); an inclined air guide plate (21) is provided on the air guide pipe (20); one end of the air outlet (19) is connected to the air guide pipe, and the other end passes through the air guide plate (21).

4. The gas uniform mixer according to claim 3, characterized in that: The end of the air guide plate (21) connected to the air guide pipe (20) has a greater thickness, and the end away from the air guide pipe (20) has a smaller thickness. The end of the air guide plate (21) away from the air guide pipe (20) is provided with a serrated edge, and the air outlet hole (19) corresponds to the tip of the edge of the air guide plate (21).

5. The gas uniform mixer according to claim 3, characterized in that: The air guide plate (21) is provided with a spoiler column (22) corresponding to the end of the air outlet hole (19).

6. The gas uniform mixer according to claim 1, characterized in that: A spoiler connected to the inner wall of the cylinder (1) is provided between the distributor (5) and the rear end connection portion (9), wherein the spoiler is composed of a plurality of spoilers (23) arranged in sequence, and two adjacent spoilers (23) are coaxial and in opposite directions.

7. The gas uniform mixer according to claim 6, characterized in that: The spoiler (23) comprises an outer ring (24), connecting rods (25) and spoiler rods (26); a plurality of connecting rods (25) are distributed in an annular array within the outer ring (24); and a spoiler rod (26) is provided between two adjacent connecting rods (25).

8. The gas uniform mixer according to claim 1, characterized in that: The rectifier (4) comprises a sleeve (27), a partition plate (28) and a spacer plate (29); the partition plate (28) divides the space inside the sleeve (27) into a plurality of fan-shaped cavities; the spacer plate (29) divides the space inside the fan-shaped cavity into a plurality of triangular cavities; the cross-sectional areas of the plurality of triangular cavities gradually decrease in a direction from the central axis of the cylinder (1) to the outer wall of the cylinder (1).

9. The gas uniform mixer according to claim 1, characterized in that: The length-to-diameter ratio of the cylinder (1) is 4-6, and flanges (6) are provided at both ends of the outer wall of the cylinder (1).

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