RU172835U1 - Direct-flow mass transfer plate for gas and liquid separation processes - Google Patents

Abstract

The utility model relates to the hardware design of mass transfer processes in steam (gas) - liquid systems and can be used in the chemical, petrochemical and food industries. The technical result is achieved by using a direct-flow mass transfer plate for the separation of gas and liquid media, consisting of a horizontal web with sparging elements and an overflow device in the form of a streamlined static hydraulic lock, the front wall of which is made with a slope of 12-15 degrees to the wall of the column body, with a protruding overflow threshold, the front wall of which is two times higher than the rear wall, made in the form of blinds with bent upper edges of the slit, and the height of the side walls is equal to Roughly varies from its front to the back wall, while between the bubbling elements and the protruding overflow threshold, with a slope in the direction of the vapor-liquid flow, a forplank is installed with a length equal to the length of the front wall of the protruding overflow threshold. The technical result is to increase the performance of the mass transfer plate and improve the quality of separation.

Description

The utility model relates to the hardware design of mass transfer processes in steam (gas) - liquid systems and can be used in the chemical, petrochemical and food industries.

Currently, mass transfer plates with cross-phase movement are most widely used, liquid flows along the plate in the direction of the overflow device, and gas (steam) sparges through the liquid layer on the plate and once-through plates in which gas (steam) and liquid move in the same direction: from the wall of the column to the overflow device. The overflow device of the mass transfer plate has a significant impact not only on the performance of the mass transfer plates, but also on the installation of the plates in the column apparatus. The design of the overflow device is characterized by its throughput, that is, the permissible fluid velocities in the receiving pocket, determined by the conditions for the separation of the two-phase flow, as well as the installation conditions, in which the installation accuracy and the depth of the hydraulic seal must be ensured in order to exclude the leakage of steam through the overflow device. Some designs of overflow devices determine the magnitude of the liquid gradient on the plate, which increases the uniformity of flows along the cross section of the column. In some cases, the method of creating a water seal affects the performance of the plate, the range of its stable operation, as well as the size of the entire apparatus.

A known design of a mass transfer plate (JP patent No. 57034002, IPC B01D 3/22, 1982), consisting of a horizontal web mounted on ring supports, bubble elements, as well as overflow devices forming a water seal in the inter-tray space of an inclined conical and horizontal ring elements, in which the function of the receiving pocket is the cavity between the drain edge of the plate and the column body.

The disadvantages of this design are, first of all, the lack of liquid distribution over the cross-section of the column, since the distribution is carried out only by spraying liquid from the annular support on the wall of the column, parts of the overflow device are mounted on different nodes, the inclined cone is mounted on a plate, and the annular support forming a dynamic water lock - on the wall of the column, which requires accuracy of their mutual installation, in addition, spraying liquid from a height of the location of the dynamic shutter cannot provide smooth flow of fluid on the underlying plate.

Known steel solid distillation plates of a typical design, in which liquid from an overlying plate enters through a drain threshold into a receiving pocket of a segment shape and is evenly distributed through the overflow threshold along the front of the base of the plate and moves in the diametrically opposite direction to the drain threshold and further through the receiving pocket to the next plate . Gas (steam) rises from the underlying tray, sparges through the liquid and goes up. The receiving pocket, partially filled with liquid, performs the function of a water trap, preventing gas from penetrating upwards through the overflow device (Machines and equipment for chemical production: a textbook for universities / A. Timonin, B. G. Baldin, V. Ya. Borschev, Yu.I. Gusev et al. // 2008 .-- 872 p. - S. 556).

The disadvantages of this design are the irrational use of the working area of the plate, since a significant part of it is occupied by an overflow device and is thus excluded from the process of active mass transfer, which ultimately reduces the performance of the column, in addition, the installation of plates requires the accuracy of combining two elements, located on different plates, the segment-shaped receiving pocket is mounted on a higher located plate, and the overflow threshold, which forms a water seal together with the overflow pocket, is on the bottom her plate.

A known design of the contact plate for carrying out heat and mass transfer processes with an overflow nozzle and a disk located under it, mounted on a vertical axis (ed. St. SU No. 375077, IPC B01D 3/20, 03/23/1973). The disk is equipped with guide vanes located on the nozzle side.

The disadvantage of this design is poor steam separation, since the vapor-liquid flow directly from the plate into the overflow pipe, and the water seal depends on the gap between the lower end of the overflow pipe and the disc.

Known design of the valve plate (autosw. SU 341498, IPC B01D 3/30, 14.6.1972), equipped with direct-flow valves with slots and vertical partitions having in the lower part of the hole for leveling the liquid level over the entire area of the plate, receiving and overflow pockets .

The disadvantages of this design of the overflow device are the large area occupied by its elements, creating a water seal, which reduces the working surface of the plate, requires accurate assembly of elements, in particular, combining the water seal nodes.

A known design of an overflow device (patent RU No. 2158624, IPC B01D 3/20, 10.11.2000) used in gas dehydration absorbers, separators, filters or sections of multifunctional mass transfer apparatuses, and contains a curved pocket with an inlet and outlet nozzle that is shorter than the inlet and equipped with a valve connected to the float. The float is installed inside the outlet pipe and is connected to the valve, which is located on the outlet pipe, a rod equipped with a lift limiter and placed with the possibility of vertical movement in guides fixed to the wall of the outlet pipe by brackets. The lower part of the outlet pipe is located below the lower part of the inlet pipe and is equipped with a removable plug. The device ensures reliable operation of the device due to the filling of the overflow device with process fluid during operation of the device and preventing the emptying of the overflow device during pulsating operation modes of the device.

The disadvantage of this design is poor steam separation, since the vapor-liquid flow enters directly from the plate into the overflow pipe.

The closest is the mass transfer plate for the separation of gas and liquid media, consisting of a horizontal web with bubble elements, overflow devices, including a receiving pocket, overflow threshold and drain threshold, an overflow device that forms a permanent static hydraulic lock, made autonomous as a whole and is attached from the bottom in the hole of the horizontal plate cloth hanging between the plates with the protrusion of the overflow pocket part above the plate cloth, which is the overflow threshold, The holes for draining the liquid are well made, the receiving pocket of the overflow device is closed from below with a guide plate directing the downward flow of liquid to the column wall, on which the drain threshold is rigidly fixed, which mainly forms an obtuse angle with this plate, and the chipper lowered into the receiving pocket forms a gap, the cross section of which is not less than the gap between the upper edge of the drain threshold and the said chipper, the shape of the edge of the guide plate repeats mainly the shape of the forming wall of the column, e, the water seal imposed on a working surface, increases a working area of mass transfer (patent RU №2438748, IPC B01D 3/16, 10.01.2012).

This design does not fully solve the technical problem, since the guide plate that covers the receiving pocket from below creates a lot of resistance to the upward flow of steam, in addition, creates stagnant zones, which reduces the efficiency of interaction between the vapor and liquid phases.

The objective is the purposeful design development of a direct-flow mass transfer plate with an autonomous suspension overflow device with an expansion of the range of properties of shared media (low foaming) and improved gas separation.

The technical result of the utility model is to increase the performance of the mass transfer plate and improve the quality of separation.

The technical result is achieved by using a direct-flow mass transfer plate for the separation of gas and liquid media, consisting of a horizontal canvas with sparging elements and rigidly fixed in the hole of the canvas plate overflow device, made in the form of a static valve with a protruding overflow threshold, in the walls of which holes are made in the form horizontal slots located above the plate cloth, while the front wall of the static valve, below the plate cloth, nene with a slope of 12-15 degrees to the wall of the column body, and the profile of the static hydraulic seal is streamlined, in addition between the bubbling elements and the protruding overflow threshold, with a slope in the direction of the vapor-liquid flow, a forplank is installed, the length of which corresponds to the length of the front wall of the protruding overflow threshold, and the front wall of the protruding overflow threshold is two times higher than its rear wall, made in the form of blinds with bent upper edges of the slit, and the height of the side walls of the protruding the overflow threshold varies uniformly from its front to the back wall.

Direct-flow mass transfer plate for the processes of separation of gas and liquid media is characterized by the fact that the sparging elements on the plate are staggered.

The essence of the technical solution lies in the reconstruction of a direct-flow mass transfer plate and a self-contained suspension type overflow device, the water trap of which is removed from the working area of the plate canvas into the inter-tray space, and the problem is solved by the following design features:

- the front wall of the protruding overflow threshold is twice as high as its rear wall, and the height of the side walls of the protruding overflow threshold evenly changes from its front to the back wall, significantly reducing the transfer of the vapor-liquid layer from the plate directly into the overflow pocket, and when it hits the wall, the separation of this flow, the liquid flows down, and the steam rises up, which ultimately allows you to increase the performance of the mass transfer plate by increasing throughput its overflow device and improving gas (vapor) separation therein.

- additional installation between the bubbling elements and the protruding overflow threshold inclined in the direction of the vapor-liquid flow forplank, the length of which corresponds to the length of the front wall of the protruding overflow threshold, allows you to drain the liquid flowing from the front wall into the drain holes and to the walls of the column, excluding the return of fluid to the plate , which provides an increase in the performance of the mass transfer plate by improving the separation of gas (steam).

- execution of the front wall of the static hydraulic lock, below the plate of the plate, with a slope of 12-15 degrees to the wall of the column body, and the streamlined shape of the bottom of the pocket reduce hydraulic resistance to vapor flow, eliminate the formation of stagnant zones and increase the performance of the mass transfer plate.

The proposed design reduces the labor and installation time of plates due to the fact that the overflow device is self-contained with rigidly fixed elements, it can be pre-mounted on a plate and installation is reduced to the installation of plates.

In FIG. 1 shows a direct-flow mass transfer plate;

in FIG. 2 shows a straight-through mass transfer plate in a section (view along AA).

Direct-flow mass transfer plate for the separation of gas and liquid media consists of a horizontal sheet 1 with bubble elements 2 and a plate of overflow device 3 rigidly fixed in the hole of the sheet 1, made in the form of a static hydraulic lock 4 with a protruding overflow threshold 5, in the walls of which openings 6 in horizontal slots located above the plate 1 of the plate. The front wall 7 of the static hydraulic lock 4 below the canvas 1 plates made with a slope of 12-15 degrees to the wall 8 of the column body, and the profile of the static hydraulic lock 4 is made streamlined. Between the bubbling elements 2 and the protruding overflow threshold 5, a preplan 9 is installed, the length of which corresponds to the length of the front wall 10 of the protruding overflow threshold 5. Forplan 9 is installed with an inclination in the direction of movement of the vapor-liquid flow. The front wall 10 of the protruding overflow threshold 5 is two times higher than its rear wall 11, made in the form of blinds with bent upper edges of the slit, and the height of the side walls 12 of the protruding overflow threshold 5 varies uniformly from its front 10 to the rear 11 of the wall.

Bubbling elements 2 on the plate can be staggered to maximize the use of the area of the canvas 1 plate.

The mass transfer plate works as follows: the liquid phase enters from the upstream plate through a static hydraulic lock 4 to a horizontal sheet 1 below the located plate and moves along the sheet to the overflow threshold 5. A part of the clarified liquid through the openings 6 enters the static hydraulic lock 4, the main part of the liquid in the form of vapor-liquid (gas-liquid) mixture flows into a static hydraulic lock 4 through the top of the rear wall 11 of the overflow threshold 5 of the overflow device 3. Due to the pressure difference created oprotivleniem plates, in static water seal 4 is automatically set to a specific level of the liquid. The liquid level in the static valve 4 provides good gas separation, since gas bubbles in the liquid must overcome the column of liquid in which the hydrostatic pressure increases. The reliability of the static valve 4 eliminates the penetration of the gas phase through the overflow device 3.

The vapor (gas) stream rises from the bottom up, passes through the bubbled elements 2 and comes into contact with the liquid phase, as a result of which mass transfer is carried out, and the performance of the plate is largely determined by the area of the active interaction of the phases.

The proposed structural elements of the mass transfer plate have the following advantages in comparison with the prototype and the base object:

- no installation of the drain and overflow slats is required, since the liquid level on the plates is provided by a part of the proposed design of the overflow device protruding above the plate;

- functionally related elements of the proposed overflow device, installed at certain angles, provide a smooth entry of liquid and steam onto the plate;

the proposed overflow device provides good gas separation due to the height of the liquid column in the receiving pocket and the use of foreplank;

allows you to increase the throughput of the overflow device due to additional holes in the walls of the overflow threshold located above the surface of the plate canvas.

Thus, the use of a direct-flow mass transfer plate for the separation of gas and liquid media, in which a forplank is installed between the bubblers and the overflow threshold with a slope in the direction of the vapor-liquid flow, the front wall of the static valve is made with a slope of 12-15 degrees to the wall of the column body , the profile of the static hydraulic seal is streamlined, and the front wall of the protruding overflow threshold is two times higher than its rear wall, which provides increased production elnosti mass transfer trays and improving the quality of separation.

Claims (2)

1. Direct-flow mass transfer plate for the separation of gas and liquid media, consisting of a horizontal canvas with sparging elements and rigidly fixed in the hole of the canvas plate overflow device, made in the form of a static valve with a protruding overflow threshold, in the walls of which holes are made in the form of horizontal slots, located above the plate cloth, characterized in that the front wall of the static hydraulic seal, below the plate cloth, is made with a slope of 12-15 degrees to the wall column, and the profile of the static hydraulic seal is streamlined, in addition between the bubbling elements and the protruding overflow threshold, with a slope in the direction of the vapor-liquid flow, a forplank is installed, the length of which corresponds to the length of the front wall of the protruding overflow threshold, and the front wall of the protruding overflow threshold is two times higher its rear wall, made in the form of blinds with bent upper edges of the slit, and the height of the side walls of the protruding overflow threshold is uniformly changed Xia from the front to the back wall. 2. Direct-flow mass transfer plate according to claim 1, characterized in that the sparging elements on the plate are staggered.

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