CN2396883Y - Conical cyclone gas distributing machine - Google Patents

Abstract

A conical swirling gas distributor, which is a conical frustum without upper and lower bottoms, with multiple gas passages on the conical surface, deflectors on all or part of the gas passages, and deflectors A longitudinal side is connected to the edge of the gas passage, and is folded toward the frustum of the cone, forming an included angle of 20-70° with the tangent plane of the connecting side. The utility model adopts the conical swirl type gas distributor with small pressure drop, good gas distribution effect, easy gas-liquid phase separation, can eliminate mist entrainment, and has a simple structure.

Description

Cone swirl gas distributor

The utility model relates to tower equipment and reactor parts, in particular, it is a gas distributor that makes the flow rate of the gas phase entering the tower or reactor more uniform on the entire equipment section.

With the increasingly large-scale chemical production, large-diameter tower equipment and reactors continue to emerge, and some of them have a diameter of more than ten meters. For towers and reactors with large diameters (above φ2000), once the initial distribution of the inlet gas is not uniform, it will inevitably affect the mass transfer, heat transfer and reaction effects in the equipment, and in severe cases, it will cause pulsation and runaway temperature of the gas-liquid reactor. Partial penetration and deactivation of the catalyst bed, and a substantial drop in the mass transfer efficiency of the separation tower. Therefore, in recent years, the research and development of the initial distribution of chemical equipment at home and abroad have paid much attention to the research and development of the initial distribution of the chemical equipment, and have developed a multi-hole straight tube type, straight tube baffle type, tangential horn type, single tangential circulation type, double row blade type, etc. Various intake initial distributors. However, the gas distribution effect of these distributors is not ideal, and some have disadvantages such as high pressure drop and serious mist entrainment. In order to further enhance the gas distribution effect, Glitsch has developed a double tangential circular flow inlet distributor. Its structure is shown in Figure 1, but the results of use show that there are still: more airflow in the center of the tower; less airflow around the wall of the tower , when the air flow is reversed, it is easy to stir up the liquid layer at the bottom of the tower to form serious mist entrainment and other problems. Recently, Tianjin University has developed a radial air inlet distributor. Its structure is shown in Figure 2. Although this distributor can make the gas distribution more uniform, it has a large pressure drop, a complex structure, and high cost. In the liquid phase, it is difficult to achieve gas-liquid phase separation.

The purpose of the utility model is to provide a cone-shaped swirling gas distributor with small pressure drop, good gas distribution effect, easy gas-liquid phase separation, eliminating mist entrainment, and simple structure.

The technical scheme of the utility model is as follows:

A conical swirling inlet distributor for towers and reactors, it takes the thin-walled cone as shown in Figure 3 as the main body, the cone is concentric with the separation tower or reactor equipment, and the large diameter of the cone is The diameter is similar to the diameter of the equipment and meets the assembly requirements. The angle between the cone surface and the axis of the equipment is α=20-75°, preferably α=30-60°. The frustum height H is related to both the tower diameter D and the inlet pipe diameter d, generally H=(0.3～1.5)D, preferably H=(0.4～1.0)D, H=(0.5～10)d. The upper and lower end faces of the cone are perpendicular to the axis of the equipment, the outer diameter of the large diameter end is slightly smaller than the inner diameter of the equipment, and the gap between the two should meet the needs of equipment installation.

There are several gas passages uniformly distributed along the circumferential direction on the conical surface. Generally, the number of gas passages is 3 to 24, and the preferred number is 5 to 12, depending on the diameter of the equipment and the amount of air intake. The gas channel can be rectangular, trapezoidal or parallelogram, etc. The channel width direction is consistent with the circumferential direction, the width L=(0.1～0.5)d, the preferred value is L=(0.15～0.25)d, when the channel is trapezoidal, the width L refers to the average value of the upper and lower bottom of the trapezoid, the bottom edge The angle β with the waist is 60-90°. The channel height h=(0.2～0.9)H, the preferred value is h=(0.4～0.8)H, which needs to be determined according to the situation of the intake air. There are deflectors on all or part of the passages. When some are installed, the ratio of whether there are deflectors can be 1:2, 1:1, 2:1. The setting of deflectors should be evenly distributed along the circumferential direction. When the ratio of the number of gas passages with and without deflectors is 2:1, three gas passages with—without—with deflectors should form a group, and each group is evenly distributed along the circumferential direction. The deflector can be rectangular, trapezoidal, or arc-shaped stamped from a rectangular shape. The deflector height h ₁ is equal to h, the width L ₁ =(0.8-1.5)L, the preferred value is L ₁ =(0.9-1.2)L, and L ₁ =L is often taken. The connection mode of the deflector and the gas channel is shown in Figure 4. The manufacturing method is as follows: when opening the gas channel on the cone, keep a certain longitudinal side without cutting, and then fold it into the cone to form the deflector at the required angle; the deflector can also be made separately Finally, welding (or bonding, etc.) on a certain long side of the gas channel. The included angle γ between the guide plate and the tangent plane of the connecting edge is 20-70°, preferably γ=30-60°. The deflector is arranged clockwise (or counterclockwise), and the specific form is shown in Figure 4.

The gas distributor can be made of metal plate, engineering plastic or inorganic non-metallic material. When metal plates are used, the whole plate can be coiled and welded, or it can be made by block welding. The utility model can be used as a gas distribution and redistributor for air intake at the top, middle and lower parts of the equipment. When used as an air intake distributor, the axis of the intake pipe should be aligned with a certain gas channel with a guide baffle along the height direction centerline of . When the gas flows upwards, the large diameter end of the frustum is on the top, and the lower edge of the small diameter end of the frustum can be serrated 2. Generally, the height of the serrations is H ₁ =(0-0.3)d or H ₁ =(0-0.2)H. The pitch S=(0.5-2)H ₁ of the sawtooth is uniformly distributed along the circumferential direction of the end face. When the gas flows downward, the large diameter end is downward. The large-diameter end of the frustum should be fixed to the wall of the equipment. Under the principle of avoiding the gas passage, the distributor and the equipment are fixedly connected with 3 to 12 oblique supports. One end of the oblique support is connected to the middle of the distributor, and the other end is fixed on the equipment. On the wall, the included angle with the equipment wall is 30-45°, and the supports are evenly distributed along the circumferential direction. If necessary, 3 to 12 supports can be set at the bottom of the distributor, and the supports are evenly distributed along the circumferential direction. In addition to supporting the distributor, they can also be used for positioning the distributor. When the base is used, the top of the distributor is provided with a plurality of positioning plates uniformly distributed along the circumferential direction.

The cone circulation gas distributor of the utility model has the following characteristics:

1. Most of the gas enters the distributor evenly along the periphery of the distributor, and the gradual expansion structure of the flow channel is used to make the gas evenly distributed on the entire cross-section, and there is no fluid flow dead zone of the distributor such as the double tangential circulation type. Good distribution.

2. When the gas flows upwards, the flow rate of the gas turning upwards from the small-diameter end of the distributor is low, which will not cause the phenomenon of stirring up the liquid at the bottom and entraining the mist.

3. For the liquid phase entrained in the intake air, a small part rushes straight to the gas channel with the deflector plate, hits the deflector plate due to inertia, gathers and falls. The untrapped liquid phase enters the distributor tangentially along with the gas flow. Because the flow section expands after the gas enters the distributor, the axial and radial flow velocities are much smaller than the flow velocity in the inlet pipe, so there is a large space and time for the gas to flow into the distributor. The droplets are separated by gravity and centrifugal sedimentation in the airflow; most of the fluid first turns to flow along the side wall, some of the droplets are thrown to the wall by the centrifugal force, and some of them hit the outer wall of the distributor and are trapped. When the untrapped droplets enter the gas channel with deflectors, the situation is the same as the previous analysis. When entering the gas passage without a deflector, because it flows in along the wall and is impacted by the fluid adjacent to the air inlet passage with a deflector, it will not rush straight to the center of the equipment, but will be accompanied by other fluids flow and achieve gas-liquid phase separation. At the same time, the collision of multiple streams of fluids with different flow directions can not only make small droplets aggregate and grow, but also the loss of gas phase kinetic energy in the collision is also conducive to the falling and separation of droplets. For the above reasons, the gas mist entrainment of this distributor is very small.

4. The gas passage without deflector prevents the gas from excessive rotation along the wall, resulting in a large flow along the side wall and a small flow along the center, further improving the axial flow velocity distribution of the gas.

5. Due to the large area of the gas channel and the short process, and the gas enters the equipment, it is gradually diverted in a guided manner, and gradually expanded to the entire cross-section, so the pressure is reduced and the energy consumption is small.

6. The distributor has simple structure, less materials, convenient manufacture and maintenance, and low cost.

Description of drawings:

Accompanying drawing 1. Schematic diagram of the double tangential circulation type inlet initial distributor of Glitsch Company;

Accompanying drawing 2. Schematic diagram of the radial intake initial distributor with umbrella deflector;

Accompanying drawing 3. Schematic diagram of the structure of the frustum swirling gas distributor, a. front view, b. top view;

Accompanying drawing 4. Schematic diagram of the deflector layout of the cone swirl gas distributor;

In the figure: 1. Conical frustum; 2. Sawtooth; 3. Gas conduction; 4. Deflector.

Further illustrate the utility model by example below.

Embodiment one. Acetic acid-water system rectification column renovation, using cone swirl gas distributor. Tower diameter D = 3000mm, bottom air intake, intake pipe diameter d = 1000mm, height of the designed conical swirl gas distributor H = 1500mm, angle α between the cone surface and the axis of the equipment = 20°, number of air intake channels There are 12 intake passages, 3 widths L=150mm, height h=1200mm, the channel ratio of setting and not setting deflectors is 2:1, the height _h1 =1200mm of deflectors 4, width _L1 =150mm, and The included angle γ=30° formed by the tangent planes of the connecting sides. The frustum 1 adopts 6 oblique supports, the frustum and the supports are made of SUS 317L stainless steel, the wall thickness of the frustum is 10mm, and it is assembled and welded by 6 pieces. After adopting the distributor, the distribution of the inlet gas at the bottom of the tower is greatly improved, and the unevenness of the gas phase distribution is reduced from 127% to 32%, so that the acetic acid content in the bottom of the tower is increased from 93% to 95%, and the whole tower The pressure drop did not increase significantly.

Embodiment two. A fixed-bed catalytic reactor has a diameter of D = 3200mm, upper air intake, and the diameter of the intake pipe is d = 800mm. Before the transformation, the average service life of the catalyst was 7300 hours. The height of the conical swirl gas distributor was H=1200mm, α=60°, the number of channels was 10, the width of the gas channel 3 was L=200mm, and the height h=480mm. It is 1:1 with the channel ratio without deflector, the deflector 4 is high h ₁ =480mm, wide L ₁ =200mm, and the included angle γ=45° formed by the plane tangent to the connecting edge, adopting the gas of the utility model After the distributor, after the utility model, the gas phase distribution of the inlet distribution catalyst and the bed section is obviously improved, and the average life of the catalyst is extended by 680-720 hours compared with that before the transformation, and the economic benefit is obvious.

Claims (8)

1. cone spiral-flow type gas distributor, it is characterized in that it be one supreme, the frustum of going to the bottom (1), frustum (1) is concentric with knockout tower or reactor apparatus, the major diameter of frustum (1) is similar to device diameters, satisfy matching requirements, angle α=20～75 of the conical surface and equipment axis °, have a plurality of on the conical surface along the uniform gas passage (3) of frustum (1) circumferencial direction, all or part of gas passage is provided with deflector (4), deflector (4) is along the circumferential direction uniform, a longitudinal edge of deflector (4) is connected on the edge of gas passage (3) of frustum (1), and turns in frustum and analyse, and forms angle γ=20～70 ° with the fillet tangent plane.

2. according to right 1 described gas distributor, it is characterized in that the height H of frustum (1) and device diameters D satisfy following relation: H=(0.3～1.5) D.

3. gas distributor according to claim 1 is characterized in that the height H of frustum (1) and air inlet pipe diameter d satisfy following relation: H=(0.5～10) d.

4. gas distributor according to claim 1 is characterized in that having 3～24 on the conical surface of frustum (1).

5. gas distributor according to claim 4, the preferred amount that it is characterized in that gas passage (3) is 5～12.

6. gas distributor according to claim 1, it is characterized in that gas passage (3) is a rectangle, trapezoidal or parallelogram, there are the following L=of relation (0.1～0.5) d in the width L of gas passage (3) and air inlet pipe diameter d, and there is following relation: h=(0.2～0.9) H in the height H of the height h of gas passage (3) and frustum (1).Distributor according to claim 1 is characterized in that it and equipment are that concentric is fixed.

7. gas distributor according to claim 1 is characterized in that deflector (4) is a rectangle or trapezoidal, its height h ₁Equate width L with the height h of gas passage (3) ₁=(0.8～1.5) L (L is the gas passage width).

8. gas distributor according to claim 1, when it is characterized in that gas distributor is used for equipment that gas upwards flows, the larger diameter end of frustum (1) is last, and smaller diameter end is down, and the lower edge of frustum (1) smaller diameter end has sawtooth (2).

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