CN220779045U - Tray structure of extractive distillation tower - Google Patents

Abstract

The utility model discloses a tray structure of an extractive distillation column, which comprises a plurality of layers of trays, wherein an odd layer of trays comprise two half trays which are correspondingly arranged, each half tray comprises a first tray, the arc-shaped edge of the first tray is connected with a column body to form a liquid receiving tray, the straight edge of the first tray is connected with a liquid falling plate, and a liquid descending channel is formed between the liquid falling plates of the two half trays; the even-layer tray comprises a second tray plate, two opposite arc edges of the second tray plate are connected with the tower body to form a liquid receiving disc, the liquid receiving disc of the even-layer tray is positioned in the middle of the second tray plate, two opposite straight edges of the second tray plate are connected with a liquid falling plate, and a liquid descending channel is formed between the liquid falling plate of the even-layer tray and the tower body; the height of the overflow weir of the tray of the upper half part is higher than that of the tray of the lower half part; a plurality of caps are arranged on the tray of the odd layer and the tray of the even layer. The utility model has the characteristics that impurities are not easy to deposit on the tray and stably run for a long time.

Description

Tray structure of extractive distillation tower

Technical Field

The utility model relates to the technical field of distillation towers, in particular to an extractive distillation tower tray structure.

Background

At present, most of the solvents used in the extractive distillation tower are sulfolane, and because the sulfolane is inevitably subjected to oxidative decomposition and hydrolysis during the use period, the pH value of the solvents is reduced, and monoethanolamine needs to be periodically injected into the system to reduce corrosion, so that the betaine of the system is gradually increased along with the prolongation of the operation time, and meanwhile, the pH value of the solvents is reduced and the acidity is enhanced, so that on one hand, equipment corrosion is aggravated, mechanical impurities and sulfonates are generated by corrosion, and on the other hand, high-boiling-point substances are generated by olefin polymerization are increased. Although most impurities are removed by means of a solvent filter, a solvent regeneration tower and the like, some mechanical impurities and high-boiling impurities still enter the extractive distillation tower and are gradually deposited on the surfaces of the tray and the float valve, so that the float valve is difficult to open or can not be opened. The efficiency of the extractive distillation tower is gradually reduced after the extractive distillation tower runs for about 18 months, and the phenomena of temperature reversal, flooding and the like of a feeding section occur, so that the full-load long-period running of the device is affected, and a plurality of refineries are plagued.

Disclosure of Invention

The utility model provides a tray structure of an extractive distillation tower, which aims to solve the problem that mechanical impurities and high-boiling impurities are deposited on a tray after the extractive distillation tower is operated for a long time.

In order to solve the technical problems, the utility model comprises a plurality of layers of trays arranged in a tower body, and the structure is characterized in that: the odd-layer trays in the tower body comprise two half trays which are correspondingly arranged, each half tray comprises a first tray plate, the arc-shaped edge of each first tray plate is connected with the tower body to form a liquid receiving tray, the straight edge of each first tray plate is connected with a liquid falling plate, a liquid descending channel is formed between the liquid falling plates of the two half trays, and the liquid receiving tray of the adjacent even-layer tray is arranged below the liquid falling plate of each half tray; the even-layer tray comprises a second tray plate, two opposite arc edges of the second tray plate are connected with the tower body to form a liquid receiving tray, the liquid receiving tray of the even-layer tray is positioned in the middle of the second tray plate, two opposite straight edges of the second tray plate are connected with a liquid reducing plate, a liquid descending channel is formed between the liquid reducing plate of the even-layer tray and the tower body, and the liquid receiving tray of the adjacent odd-layer tray is arranged below the liquid reducing plate of the even-layer tray; the overflow weir is formed at the joint of the liquid-falling plate, the first tower plate and the second tower plate, and the height of the overflow weir of the tray at the upper half part in the tower body is higher than that of the overflow weir of the tray at the lower half part; and a plurality of caps for gas and liquid to pass through are arranged on the odd-layer trays and the even-layer trays.

After the structure is adopted, gas in the tower flows from bottom to top through the caps of each layer of tower tray, liquid flows from the upper layer of tower tray to the adjacent lower layer of tower tray, and the gas can disturb the liquid and transfer mass when passing through the caps; the odd-layer tray comprises two half trays which are correspondingly arranged, a liquid receiving tray of the half trays is positioned at the edge close to the inner wall of the tower body, and the liquid of the liquid receiving tray flows to the straight edge in the middle and then flows to the even-layer tray below along the liquid dropping plate; the liquid receiving tray of the even-layer tray is positioned in the middle of the tray, and liquid flows from the liquid receiving tray to straight sides at two sides and then flows onto the odd-layer tray below along the liquid dropping plate. The structure of the tray structure is different between the odd-layer tray and the even-layer tray, the odd-layer tray comprises two trays, liquid flows from liquid receiving discs at two sides to a liquid reducing plate at the middle, the even-layer tray is one tray, liquid flows from the liquid receiving disc at the middle to the liquid reducing plate at two sides, the existing tray structure is that the liquid flows from the liquid receiving disc at one side of the tray to the liquid reducing plate or a downcomer at the other side, the flowing distance of the liquid is longer, and the flowing distance of the liquid in each tray structure is shorter, so that the deposition of mechanical impurities and high-boiling impurities caused by long-distance flowing of the liquid can be reduced; the liquid in the tray of the lower half part in the tower body has higher mechanical impurity and high boiling point impurity content, the overflow weir height of the tray of the lower half part is set lower, the liquid layer thickness is reduced, the mechanical impurity and the high boiling point impurity are carried out when the liquid flows, the disturbance effect of gas on the liquid on the tray of the lower half part is stronger, and the deposition of the mechanical impurity and the high boiling point impurity is further reduced. The tray structure can reduce the deposition of mechanical impurities and high-boiling impurities on the tray, further reduce the probability of phenomena such as efficiency reduction, temperature difference inversion of a feeding section, flooding and the like of the extractive distillation tower, and realize long-term stable operation of the device. In addition, the tray structure does not adopt a float valve, and the problem that the float valve is difficult to open due to deposition of mechanical impurities and high-boiling impurities can be avoided.

Further, the height of the overflow weir of the odd-numbered trays in the upper half tray in the tower body is higher than that of the even-numbered trays, and the height of the overflow weir of the odd-numbered trays in the lower half tray in the tower body is higher than that of the even-numbered trays.

Furthermore, the height of the overflow weir of the tray of the odd layer in the tray of the upper half part in the tower body is 19-21mm, and the height of the overflow weir of the tray of the even layer is 14-16mm; the height of the overflow weir of the tray in the odd layers in the tray at the lower half part in the tower body is 12-14mm, and the height of the overflow weir of the tray in the even layers is 5-7mm.

Further, a plurality of air passing holes are formed in the first tower plate and the second tower plate, the cap cover is arranged on the upper surfaces of the first tower plate and the second tower plate which are opposite to the air passing holes, the cap cover comprises a cylinder body which is vertically communicated, a notch is formed in the bottom of the side face of the cylinder body, a plurality of supporting columns are arranged at the top of the cylinder body, and the upper ends of the supporting columns are connected with the top plate.

Further, the edge of the top plate is connected with a demisting cover, and a plurality of holes are formed in the demisting cover.

Further, the aperture ratio of the demisting cover is 50-60%.

In the tray structure of the extractive distillation tower, the tray structures of the odd-layer trays and the even-layer trays are different, so that the flowing distance of liquid on the trays is shortened, and mechanical impurities and high-boiling-point impurity deposition are reduced; the overflow weir height of the tray at the lower half part is lower, the corresponding liquid layer thickness is also lower, the disturbance effect on liquid is stronger when gas passes through the tray, mechanical impurities and high boiling point impurities are carried out when solution flows, the deposition of the impurities on the tray is reduced, the efficiency is reduced, the temperature difference at the feeding end is reduced, and the flooding phenomenon is generated, so that the extractive distillation tower can stably run for a long time. The overflow weir height of the tray with the odd layers is higher than that of the tray with the even layers, the liquid layer thickness of the corresponding tray with the odd layers is higher than that of the tray with the even layers, the mass transfer effect of the gas and the liquid is stronger when the gas passes through the tray with the odd layers, the efficiency of the extractive distillation tower is ensured, the disturbance effect of the gas on the liquid is stronger when the gas passes through the tray with the even layers, the impurity is not deposited on the tray along with the liquid discharge, the long-term stable operation of the extractive distillation tower is ensured, the loading capacity of the device is improved, and the processing capacity of the device has certain elasticity. The cap cover is not easy to be blocked by impurities, and the demisting cover on the cap cover can separate the sprayed gas-liquid mixture. The utility model has the characteristics of difficult deposition of impurities and long-term stable operation.

Drawings

FIG. 1 is a schematic diagram of the structure of the present utility model;

FIG. 2 is a schematic plan view of an odd-level tray;

FIG. 3 is a schematic plan view of an even layer tray;

FIG. 4 is a schematic structural view of the cap;

FIG. 5 is a view in the direction A of FIG. 4;

in the figure: 1-a tower body; 2-half trays; 21-a first tray; 3-even trays; 31-a second tray; 4-a liquid-falling plate; 41-overflow weir; 5-a cap; 51-a cylinder; 52-notch; 53-support columns; 54-defogging cover; 55-top plate; 6-passing air holes; 7-liquid receiving plate.

Detailed Description

Referring to fig. 1-5, an extractive distillation tower tray structure comprises a tower body 1, wherein a plurality of layers of tower plates are arranged in the tower body 1, an odd layer of tower plates comprise two half tower plates 2 which are correspondingly arranged, the two half tower plates are particularly symmetrically arranged in fig. 1-3, each half tower plate 2 comprises a first tower plate 21, the arc-shaped edge of each first tower plate 21 is connected with the tower body 1 to form a liquid receiving plate 7 of an odd layer of tower plates, a liquid falling plate 4 is connected with the straight edge of each first tower plate 21, liquid falling channels are formed between the two liquid falling plates 4, the liquid receiving plates 7 of the odd layer of tower plates are positioned on two sides of a tower plate plane, the liquid falling plates 4 are positioned in the middle area of the tower plate plane, and liquid flows from two sides to the middle in the flowing direction of the odd layer of tower plates, and a solid arrow in fig. 2 is liquid flowing; the even-numbered layer tray 3 is a tray arranged in the middle area, the even-numbered layer tray 3 comprises a second tray plate 31, the arc edges on two opposite sides of the middle part of the second tray plate 31 are connected with the tower body 1 to form a liquid receiving tray 7 of the even-numbered layer tray 3, the liquid falling plate 4 of the odd-numbered layer tray is positioned above the liquid receiving tray 7 of the adjacent even-numbered layer tray 3, the straight edges on two sides of the second tray plate 31 are connected with the liquid falling plate 4, the liquid falling plate 4 and the inner wall of the tower body 1 form a liquid descending channel, the liquid receiving tray 7 of the even-numbered layer tray 3 is positioned in the middle area of the tray plane, the liquid falling plate 4 is positioned on two sides of the tray plane, the liquid flows from the middle to two sides in the flowing direction of the even-numbered layer tray 3, the solid arrow in fig. 3 is the liquid flowing direction, and the liquid falling plate 4 of the even-numbered layer tray 3 is positioned above the liquid receiving tray 7 of the adjacent odd-numbered layer tray. The connection part of the liquid falling plate 4, the first tower plate 21 and the second tower plate 31 forms an overflow weir 41, the height of the overflow weir 41 of the upper half tray in the tower body 1 is higher than that of the overflow weir 41 of the lower half tray, the height of the overflow weir 41 of the odd-numbered trays in the upper half tray and the lower half tray is higher than that of the overflow weir 41 of the even-numbered trays 3, specifically, the height of the overflow weir 41 of the odd-numbered trays in the upper half tray is 19-21mm, and the height of the overflow weir 41 of the even-numbered trays 3 is 14-16mm; in the bottom half tray, the height of the overflow weir 41 of the tray with the odd layer is 12-14mm, and the height of the overflow weir 41 of the tray with the even layer 3 is 5-7mm. The first column plate 21 and the second column plate 31 are provided with a plurality of gas passing holes 6 for passing gas and liquid, the upper surfaces of the first column plate 21 and the second column plate 31 are provided with caps 5 opposite to the gas passing holes 6, the main structure of each cap 5 is a cylinder body 51 which is penetrated up and down, the bottom of the side surface of each cylinder body 51 is provided with a notch 52, the cylinders 51 are arranged on the column plates to form a bottom gap, the tops of the cylinders 51 are provided with a plurality of support columns 53, the upper ends of the support columns 53 are connected with top plates 55, top gaps are formed between the support columns 53, the edges of the top plates 55 are connected with demisting covers 54, the demisting covers 54 are provided with a plurality of holes, and the opening rate is 50-60%.

The working process comprises the following steps: when the liquid layer thickness on the tray is higher than the overflow weir 41, the liquid flows from the tray of the present layer to the tray of the lower layer along the liquid falling plate 4, specifically, the liquid is baffled from top to bottom through the half tray 2 of the tray of the odd layer, the tray 3 of the even layer, the half tray 2, the tray 3 of the even layer; when gas passes through the gas holes 6 on the tower tray, liquid is carried by bottom gaps and upwards enters the cap cover 5, the gas and the liquid are mixed and contact to generate mass transfer, the gas and the liquid are sprayed outwards from the top gaps after being impacted by the top plate 55, part of liquid drops are condensed and fall onto the tower plate after being impacted by the top plate 55, the gas is sprayed out from the holes of the demisting cover 54 and upwards enters the upper tower tray, part of liquid drops fall onto the tower plate after being impacted by the upper tower plate, a small amount of liquid drops enter the upper tower tray along with the gas, and the demisting cover 54 improves the gas-liquid separation effect and prevents excessive liquid drops from entering the upper tower tray to influence the gas-liquid mass transfer efficiency of the upper tower tray. The liquid flows from top to bottom in the tower body 1, mechanical impurities and high boiling point impurities in the liquid of the tray at the lower part are higher, the overflow weir height of the tray at the lower part is low, the liquid layer thickness on the tray is also low, the disturbance effect on the liquid when the gas passes through the tray is stronger, the impurities are not easy to deposit on the tray, and the impurities are beneficial to being carried out along with the liquid flow. The liquid on the trays of the odd layers flows from the edge of the tower body 1 to the middle area, then flows onto the trays 3 of the even layers adjacent below along the liquid falling plate 4 of the half tray 2, the liquid on the trays 3 of the even layers flows from the middle area of the tower body 1 to two sides, then flows onto the trays of the odd layers adjacent below along the liquid falling plate 4 of the trays 3 of the even layers, each layer of the conventional tray structure comprises one tray, the liquid flows from the liquid receiving plate 7 on one side of the tray to the liquid falling plate 4 on the other side of the tray, the flowing distance of the liquid is long, mechanical impurities and high boiling impurities are easy to deposit, and the flowing distance of the liquid of the tray structure of the utility model on each layer of trays is short, and the mechanical impurities and the high boiling impurities are difficult to deposit due to the disturbance effect of gas. The height of the overflow weir 41 of the odd-layer tray of the upper half tray and the lower half tray is higher than that of the even-layer tray 3, the liquid layer on the odd-layer tray is larger in thickness and holds more liquid, the gas has stronger mass transfer effect with the liquid when passing through the odd-layer tray, the efficiency of the extractive distillation tower is ensured, and the shock load resistance is stronger; the liquid layer thickness on the even-numbered trays 3 is smaller, the disturbance effect of gas on liquid is larger when passing through the even-numbered trays 3, mechanical impurities and high-boiling impurities are not easy to deposit, and the impurities are easier to carry out along with the liquid, so that the extractive distillation tower can stably operate for a long time. Taking an extractive distillation tower with a set of 80 trays as an example, the height of an overflow weir 41 of an odd-numbered tray in 1-40 trays is set to be 20mm, the height of an overflow weir 41 of an even-numbered tray 3 is set to be 15mm, the height of an overflow weir 41 of an odd-numbered tray in 41-80 trays is set to be 13mm, and the height of an overflow weir of an even-numbered tray 3 is set to be 6 mm.

The tray structure of the extractive distillation tower is not easy to deposit mechanical impurities and high boiling point impurities, reduces the possibility of phenomena of reduced treatment efficiency, inverted temperature difference of a feeding section, flooding and the like of the extractive distillation tower, ensures that the extractive distillation tower can stably operate for a long time and has certain impact load resistance.

Claims (6)

1. An extractive distillation column tray structure comprising a plurality of trays mounted within a column (1), characterized by: the odd-layer trays in the tower body (1) comprise two half trays (2) which are correspondingly arranged, each half tray (2) comprises a first tray (21), the arc-shaped edge of each first tray (21) is connected with the tower body (1) to form a liquid receiving tray (7), the straight edge of each first tray (21) is connected with a liquid falling plate (4), a liquid descending channel is formed between the liquid falling plates (4) of the two half trays (2), and the liquid receiving tray (7) of the adjacent even-layer tray (3) is arranged below the liquid falling plate (4) of the half tray (2); the even-numbered layer tray (3) comprises a second tray (31), two opposite arc edges of the second tray (31) are connected with the tower body (1) to form a liquid receiving tray (7), the liquid receiving tray (7) of the even-numbered layer tray (3) is positioned in the middle of the second tray (31), two opposite straight edges of the second tray (31) are connected with a liquid reducing plate (4), a liquid descending channel is formed between the liquid reducing plate (4) of the even-numbered layer tray (3) and the tower body (1), and the liquid receiving tray (7) of the adjacent odd-numbered layer tray is arranged below the liquid reducing plate (4) of the even-numbered layer tray (3); the connection parts of the liquid-reducing plate (4) and the first tower plate (21) and the second tower plate (31) form overflow weirs (41), and the height of the overflow weirs (41) of the upper half tray in the tower body (1) is higher than that of the overflow weirs (41) of the lower half tray; and a plurality of caps (5) for gas and liquid to pass through are arranged on the tray of the odd layer and the tray of the even layer (3).

2. The extractive distillation column tray structure of claim 1 wherein: the height of the overflow weir (41) of the odd-numbered trays in the upper half tray in the tower body (1) is higher than that of the overflow weir (41) of the even-numbered trays (3), and the height of the overflow weir (41) of the odd-numbered trays in the lower half tray in the tower body (1) is higher than that of the overflow weir (41) of the even-numbered trays (3).

3. The extractive distillation column tray structure of claim 2 wherein: the height of an overflow weir (41) of an odd-layer tray in the upper half tray in the tower body (1) is 19-21mm, and the height of an overflow weir (41) of an even-layer tray (3) is 14-16mm; the height of the overflow weir (41) of the tray in the odd layer in the tray in the lower half part of the tower body (1) is 12-14mm, and the height of the overflow weir (41) of the tray in the even layer (3) is 5-7mm.

4. The extractive distillation column tray structure of claim 1 wherein: a plurality of air passing holes (6) are formed in the first column plate (21) and the second column plate (31), the cap cover (5) is arranged on the upper surface of the first column plate (21) and the second column plate (31) which are opposite to the air passing holes (6), the cap cover (5) comprises a barrel body (51) which is penetrated up and down, a notch (52) is formed in the bottom of the side face of the barrel body (51), a plurality of supporting columns (53) are arranged at the top of the barrel body (51), and the upper ends of the supporting columns (53) are connected with a top plate (55).

5. The tray structure of an extractive distillation column of claim 4 wherein: the edge of roof (55) is connected with defogging cover (54), a plurality of holes have been seted up on defogging cover (54).

6. The extractive distillation column tray construction of claim 5 wherein: the aperture ratio of the demisting cover (54) is 50-60%.