CN106693432B - Centrifugal rotational flow defoaming type gas-liquid mixed phase feeding distributor - Google Patents

Abstract

A centrifugal cyclone defoaming type gas-liquid mixed-phase feed distributor, which is characterized in that the gas-liquid mixed-phase feed port is a rectangular feed structure in a tangential direction, which is connected with the annular sleeve in the tower; the lower end of the annular sleeve is open, and the distance from the annular The lower end of the sleeve is 200-1500mm equipped with an annular grille packing for deceleration, energy absorption and degassing, with a height of 50-100mm and a width of 0.3-2.5 times the width of the annular sleeve; the middle part of the annular sleeve is closed to form an annular oil collection tank; annular sleeve The upper end of the barrel is connected to a parallel-flow packing layer with steady flow, defoaming and self-washing; the inner and outer edges of the parallel-flow packing layer are both umbrella-shaped structures, and the annular width of the packing layer is 3-500 times the spacing between packing plates.

Description

A centrifugal cyclone defoaming type gas-liquid mixed-phase feed distributor

1.Technical field

The invention provides a centrifugal cyclone defoaming type gas-liquid mixed-phase feed distributor, and relates to the field of separation towers.

2. Background technology

The tower internals are an important part of the packed tower or plate tower. Together with the tower body and trays or packing, they form a complete packed tower or plate tower. The function of all the tower internals is to make the gas-liquid two-phase Better contact within the tower in order to maximize the efficiency and production capacity of the packing or trays. The design of the tower internals will directly affect the performance of the packing or trays and the performance of the entire packed tower or plate tower.

In the chemical homogeneous separation process, gas-liquid mixed-phase feed is the most commonly encountered working condition of distillation towers, such as atmospheric and vacuum distillation towers. The gas-liquid mixed-phase feed distributor is responsible for effectively separating the vapor and liquid phases in the feed. At the same time, the vapor phase obtains good distribution along the tower cross section, and the liquid phase also has a good collection and distribution effect. A good tower feed section structure can not only stabilize the operation of the tower, but also improve the separation effect of the tower.

There are many types of gas-liquid mixed-phase feed distributors: typical ones include double tangential circulation type, single tangential circulation type, double-row blade type, tangential horn type, and radial air inlet distributor with umbrella-shaped deflector , radiant air inlet distributor with liquid capture energy absorber, etc., which are adapted to different feeding environments. Some feed distributors have good gas-liquid phase separation effect and can adapt to the requirements of large-scale towers, such as the single tangential circulation type. However, the vapor phase is unevenly distributed along the tower cross-section, and a vortex airflow will be generated in the center of the tower. ; Some feed distributors distribute the vapor phase evenly along the tower cross section, and the rising vapor flow does not entrain much liquid foam, which can adapt to the requirements of larger towers. However, the descending liquid entrains the vapor phase, which will Affects the content of light components in the product at the bottom of the tower, such as a double tangential circulation distributor; some feed distributors have a relatively uniform vapor phase distribution along the tower cross section, which can adapt to the requirements of large-scale towers, but the gas-liquid two-phase separation effect Not good, such as tangential horn type distributors; radiant air intake distributors with umbrella-shaped deflectors, especially radiant air intake distributors with liquid capture energy absorbers, which have good gas-liquid two-phase separation and good gas-liquid separation effect. The phase distribution along the tower cross-section is relatively uniform, but it cannot meet the requirements of large-scale towers.

In addition, there will inevitably be more or less entrainment of liquid foam in the rising steam flow of the gas-liquid mixed-phase feed distributor. In order to ensure the quality of the side line products, a washing section is often set up above the feeder. For example, there is a washing section above the feed section of the vacuum tower. On the one hand, the washing oil washes down the liquid, coke, asphaltene, residual carbon, heavy metals, etc. entrained in the gas through contact with the ascending stream. On the other hand, through the mass transfer between the vapor phase and the liquid phase, the heavy wax oil and residual oil can be better separated, and the dry point of the heavy wax oil can be controlled. This is the key to ensuring the quality of the heavy wax oil in the vacuum tower. In addition, the amount of washing oil must meet the requirements for wetting the filler surface to prevent coking on the filler surface. The combination of advanced washing section structure and necessary washing oil volume (minimum flow control) is adopted to avoid coking and reduce energy consumption. For vacuum towers that require minimizing pressure drop, due to the low liquid spray density in the washing section, there is easily no liquid wetting on the local packing surface. The operating temperature of the packing bed is high, and coking is prone to occur. Therefore, fillers with strong coking resistance should be selected, especially in the middle and lower parts of the filler bed. Fillers with large flux and smooth surface must be used. In addition, in order to ensure that the filler surface is fully wetted, the liquid distributor in the washing section can be a gravity distributor or a power distributor. However, due to the high operating temperature of the washing section and the low liquid spray density, the washing oil is easy to coke. Clogging makes it difficult to select the appropriate liquid distributor structure and parameters, which is also the biggest bottleneck restricting the long-term safe operation of the washing section.

3. Contents of the invention

The purpose of the present invention is to invent a centrifugal cyclone defoaming type gas-liquid mixed-phase feed distributor to overcome the shortcomings and defects of the existing gas-liquid mixed-phase feed distributor and washing section structure, which eliminates the need for liquid and vapor phases. Entrainment reduces the feeder pressure drop, achieves good gas-liquid two-phase separation, evenly distributes the vapor phase along the tower cross-section, and can meet the distribution requirements of large-scale gas-liquid mixed-phase feed towers, avoiding the need for packing and oil collection tanks The coking and clogging phenomenon has eliminated the biggest bottleneck restricting the long-term safe operation of the washing section, and achieved the good goal of a feeder that can stabilize the tower operation while improving the tower separation effect.

Technical solution of the present invention:

The invention provides a centrifugal cyclone defoaming type gas-liquid mixed-phase feed distributor, which is characterized in that the gas-liquid mixed-phase feed port is a rectangular feed structure in a tangential direction and is connected with an annular sleeve in the tower; the lower end of the annular sleeve Opening, 200-1500mm away from the lower end of the annular sleeve, an annular grid packing with guided deceleration and enhanced entrainment vapor phase separation functions is provided. The height is 50-100mm, the width is 0.3-2.5 times the width of the annular sleeve, and the spacing between the packing plates is 3- 50mm, the horizontal inclination of the packing plate is 30°-90°; the middle part of the annular sleeve is closed to form an annular oil collecting tank, and the outer wall of the bottom of the annular oil collecting tank is connected to the lower part of the annular grid packing through an external connecting pipe or the inner wall is evenly opened with equivalent Tear holes with a diameter of 5-30mm; the upper end of the annular sleeve is connected to a parallel flow packing layer with a steady flow, defoaming and self-washing function; the inner and outer edges of the parallel flow packing layer are connected in an umbrella-shaped structure, and the annular width of the packing layer is The spacing between packing plates is 3-500 times, and the spacing between packing plates is 1-30mm.

The height and width ratio of the gas-liquid mixed-phase feed port is 2-15:1, the height ratio of the gas-liquid mixed-phase feed port and the annular sleeve in the tower is 1:1-10, and the height ratio of the gas-liquid mixed-phase feed port and the annular sleeve in the tower is The width ratio of the annular sleeve is 1:1-1.5.

The annular cross-sectional area of the annular sleeve in the tower accounts for 5%-80% of the tower cross-section, and the inner wall of the annular sleeve along the height direction is a cylindrical or conical structure.

The present invention uses examples to describe the features of the present invention in detail.

4. Description of drawings

Figure 1 is a schematic structural diagram of the present invention.

The diagram description of Figure 1 is as follows:

1. Tower body 2. Gas-liquid mixed phase feed port 3. Annular sleeve 4. Annular grid packing 5. Annular oil collection tank 6. Parallel flow packing layer 7. External connecting pipe

The process features of the present invention will be described in detail below with reference to the drawings and examples.

5. Specific implementation methods

Example

A centrifugal cyclone defoaming type gas-liquid mixed-phase feed distributor is integrated with the following structure: the gas-liquid mixed-phase feed port (2) is a rectangular feed structure in the tangential direction, and is connected with the inner annular sleeve of the tower body (1) (3) are connected; the lower end of the annular sleeve (3) is open, and an annular grid packing (4) with a guide deceleration and enhanced entrained vapor phase separation function is provided 200-1500mm away from the lower end of the annular sleeve (3), with a height of 50-100mm. , the width is 0.3-2.5 times the width of the annular sleeve (3), the spacing between the annular grid packing (4) plates is 3-50mm, and the horizontal inclination of the packing plate is 30°-90°; the middle part of the annular sleeve (3) It is closed to form an annular oil collecting tank (5). The outer wall of the bottom of the annular oil collecting tank (5) is connected to the lower part of the annular grille packing (4) through the external connecting pipe (7) or the inner wall is evenly provided with tear holes with an equivalent diameter of 5-30mm. ; The upper end of the annular sleeve (3) is connected to the parallel flow packing layer (6) with the function of steady flow, defoaming and self-washing; the inner and outer edges of the parallel flow packing layer (6) are connected in an umbrella-shaped structure, and the packing layer is annular. The width is 3-500 times the spacing between packing plates, and the spacing between packing plates is 1-30mm.

The height to width ratio of the gas-liquid mixed-phase feed port (2) is 2-15:1, and the height ratio between the gas-liquid mixed-phase feed port (2) and the annular sleeve (3) in the tower body (1) is 1:1. 1-10, the width ratio of the gas-liquid miscible feed port (2) and the annular sleeve (3) inside the tower body (1) is 1:1-1.5.

The annular cross-sectional area of the annular sleeve (3) in the tower body (1) accounts for 5%-80% of the tower cross-section. The inner wall of the annular sleeve (3) along the height direction is a cylindrical or conical structure.

The centrifugal cyclone defoaming type gas-liquid mixed-phase feed distributor provided by the present invention rationally utilizes the vapor of the centrifugal cyclone through the structural coupling of the centrifugal cyclone, the annular oil collection tank, the parallel flow packing layer and the annular grid packing. The liquid two phases are well separated and suitable for large-scale expansion. The liquid volume of the annular oil collection tank is small and the downward discharge is timely and convenient. The vapor and liquid of the co-flow filler flow in the same direction and diagonally downwards at a high speed and are easy to coalesce and separate. The annular grid filler guides the deceleration. And the advantages of strengthening entrained vapor phase separation, reasonable integration to form an overall effect, not only achieves good gas-liquid two-phase separation, uniform distribution of vapor phase along the tower cross-section, but also can meet the distribution requirements of large-scale gas-liquid mixed-phase feed towers; Moreover, the vapor and liquid in the co-current packing flow diagonally downward in the same direction. The entrained liquid separated in the washing oil collection tank can maintain low liquid level operation and be discharged into the main liquid phase below the distributor in time. The liquid residence time is short, which avoids The packing and oil collecting tank are coked and blocked; in addition, the annular space structure of the centrifugal cyclone and the umbrella-shaped structure of the parallel flow packing layer ensure that the steam flow channel area of the feed distributor is greater than 50%, and the pressure drop of the feed distributor is less than 100Pa. It is crucial for the feed of the pressure reduction tower; in addition, the co-current packing stabilized flow defoaming and self-washing simplifies the structure of the washing section, solves the problem of selecting the liquid distributor of the washing section, and eliminates the constraints that restrict the long-term safe operation of the washing section. the biggest bottleneck.

Claims (3)

1. A centrifugal cyclone defoaming type gas-liquid mixed-phase feed distributor, which is characterized in that the gas-liquid mixed-phase feed port is a rectangular feed structure in a tangential direction, connected with an annular sleeve in the tower; the annular sleeve The lower end is open, 200-1500mm away from the lower end of the annular sleeve, and an annular grid packing with guided deceleration and enhanced entrainment vapor phase separation functions is installed. The height is 50-100mm, the width is 0.3-2.5 times the width of the annular sleeve, and the spacing between the packing plates is 3 -50mm, the horizontal inclination of the packing plate is 30°-90°; the middle part of the annular sleeve is closed to form an annular oil collecting tank, and the outer wall of the bottom of the annular oil collecting tank is connected to the lower part of the annular grid packing through an external connecting pipe or the inner wall is evenly opened A tear hole with an equivalent diameter of 5-30mm; the upper end of the annular sleeve is connected to a parallel-flow packing layer with a steady-flow, defoaming and self-washing function; the inner and outer edges of the parallel-flow packing layer are connected in an umbrella-shaped structure, and the annular width of the packing layer It is 3-500 times the spacing between packing plates, and the spacing between packing plates is 1-30mm. 2. A kind of centrifugal cyclone defoaming type gas-liquid mixed-phase feed distributor according to claim 1, characterized in that the height and width ratio of the gas-liquid mixed-phase feed port is 2-15:1, and the gas-liquid mixed-phase feed distributor The height ratio of the feed port to the annular sleeve in the tower is 1:1-10, and the width ratio of the gas-liquid miscible feed port to the annular sleeve in the tower is 1:1-1.5. 3. A centrifugal cyclone defoaming type gas-liquid mixed-phase feed distributor according to claim 1, characterized in that the annular cross-sectional area of the annular sleeve in the tower accounts for 5%-80% of the tower cross-section, along the height direction The inner wall of the annular sleeve is a cylindrical or conical structure.