JP3236845B2 - Internal heat exchange distillation column - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an internal device that includes a low-pressure column and a high-pressure column, and performs heat exchange between the high-pressure column (concentrating unit) and the low-pressure column (recovering unit) by transferring heat between the two. It relates to a heat exchange type distillation column.

[0002]

2. Description of the Related Art As a distillation column excellent in energy saving, a low-pressure column and a high-pressure column are provided, and heat exchange is performed between the two columns. There is known an internal heat exchange type distillation column which does not require a heat exchanger. From the viewpoint of promoting the energy saving of the distillation operation, this internal heat exchange type distillation column is the most faithful theory for energy saving, and it is natural in principle,
It is being recognized from academics.

[0003] Further, as an internal heat exchange type distillation column, a plurality of tubes (in some cases, a single tube) are connected to the main body by means of a tube plate at both ends, so that the inside and outside of the plurality of tubes are isolated inside the main body. The structure is made, and the inlet and outlet of gas and liquid are provided inside and outside the pipe, the operating temperature is made different by making the operating pressure inside and outside the pipe different, and the pipe wall of multiple pipes is used as a heat transfer surface. There has been proposed a structure in which a single distillation column is configured by transferring heat from a high pressure side to a low pressure side so that a high pressure side is a concentration section and a low pressure side is a recovery section (Japanese Patent No. 2694425). The internal heat exchange type distillation column has a structure as shown in FIGS. 7 (a) and 7 (b).

That is, in this internal heat exchange type distillation column, the main body 1 and a plurality of pipes (tubes) 25 inserted into the main body 1 are connected to both ends of a tube plate (upper tube plate (tower tube plate) 3a). It is formed by being connected to the main body 1 by a lower tube sheet (tower tube sheet) 3b). And the inside 4 of the plurality of tubes 25
And the outer tube 5 have a structure isolated from each other.

[0005] The inside 4 and outside 5 of the pipe are filled with fillers, respectively. The inside 4 is a high pressure side enrichment section, and the outside 5 is a low pressure side recovery section (however, the inside 4 can be a low pressure side collection section and the outside 5 can be a high pressure side enrichment section. Is).

At the upper part of the main body 1, there is provided a liquid inlet 6 for supplying liquid to the outside of the tube (recovery unit) 5, and a vapor outlet 7 for collecting the vapor from the outside of the tube (recovery unit) 5. A concentrating section liquid inlet 8 for supplying a liquid to the inside of the pipe (concentrating section) 4 is provided in an end chamber 14a above the top-side tube sheet 3a and communicating with the inside of the pipe (concentrating section) 4. Is arranged, and
A vapor outlet 9 for the concentrating section for extracting vapor from the pipe (concentrating section) 4 is provided.

On the other hand, at the lower part of the main body 1, a recovery section steam inlet 10 for supplying steam to the outside of the pipe (recovery section) 5, and a recovery section liquid outlet 11 for extracting liquid from the outside of the pipe (recovery section) 5. Is disposed in an end chamber 14b below the bottom tube plate 3b and communicating with the inside of the tube (concentrating unit) 4;
A vapor inlet 12 for supplying the vapor to the concentrator is provided, and a liquid outlet 13 for the liquid from the concentrator for extracting the liquid from the pipe (concentrator) 4 is provided. In this way, the pipe wall of the plurality of pipes 25 is used as a heat transfer surface, and the inside (high-pressure side) 4 of the pipes is concentrated.
One distillation column (internal heat exchange type distillation column) having the outside (low pressure side) 5 as a recovery section is formed.

By the way, in the above-mentioned internal heat exchange type distillation column, the heat transfer from the enrichment section 4 side to the recovery section 5 side and the gas-liquid contact between the flowing liquid and the ascending vapor in the enrichment section are sufficiently performed. Is very important, for example, when the enrichment section is a packed tower system, the liquid flows to the pipe wall 25a (the inner wall of the pipe 25), and the amount of liquid flowing down the pipe wall 25a becomes a nonnegligible amount and the flowing liquid The heat transfer resistance increases, the amount of liquid flowing down the surface of the packing decreases, and the gas-liquid contact efficiency decreases. May not be performed.

The present invention solves the above-mentioned problems. When the enrichment section is a packed tower system, heat transfer from the enrichment section side to the recovery section side in the distillation column and the flow-down liquid in the enrichment section are reduced. It is an object of the present invention to provide an internal heat exchange type distillation column capable of efficiently performing gas-liquid contact with rising steam and improving an energy saving effect.

[0010]

In order to achieve the above object, the internal heat exchange type distillation column of the present invention is constructed such that a single tube or a plurality of tubes are connected to a main body by means of a tube plate at both ends, thereby forming an inner part of the main body. In the structure, the inside and outside of a single or multiple pipes are separated from each other, and gas and liquid ports are provided inside and outside the pipes, and the operating temperature is increased by providing a difference in the operating pressure between the inside and outside of the pipe. An internal heat exchange type in which the high-pressure side functions as a concentrating unit and the low-pressure side functions as a collecting unit by transferring heat from the high-pressure side to the low-pressure side using the pipe wall of a single pipe or multiple pipes as a heat transfer surface. In a distillation column, a region to be a concentrating unit (in a tube or outside a tube) is filled with a structured packing, and an outer peripheral portion of the structured packing has a predetermined arrangement pitch in a height direction (axial direction). A plurality of mesh strips are wound in the circumferential direction, and On the mesh strip, a thin strip is wound in the circumferential direction, and on the upper side of both sides along the longitudinal direction of the thin strip, an upper side of 15 mm or less is arranged in the circumferential direction. At a set pitch, a plurality of cuts are formed, and the side of the thin plate-shaped body where the cut is formed abuts at least a part thereof on a tube wall that defines a region to be the enrichment section. It is characterized by being bent.

In the present invention, the mesh band means a band formed by using, for example, a wire net or a resin net material, and may be made of various materials. It is.

As described above, a plurality of mesh strips are provided on the outer peripheral portion of the structured packing to be filled in the region to be the concentrating portion (here, the case where the inside of the tube is the concentrating portion). In the width direction (axial direction), the sheet is wound in the circumferential direction so as to have a predetermined arrangement pitch, and on each mesh band, the sheet band is wound in the circumferential direction. A plurality of cuts were formed at an arrangement pitch of 15 mm or less in the circumferential direction on the upper side (tower top side) of both sides along the longitudinal direction, and cuts of the thin plate-like body were formed. By having a configuration in which one side is bent so as to come into contact with a pipe wall (an inner wall of the pipe) that defines an area to be the concentrating section, the liquid flowing down the pipe wall is
The liquid is efficiently separated from the tube wall through the bent portion (bent portion) of the thin strip and moves to the thin strip side, and the liquid transferred to the thin strip is distributed between the thin strip and the filler. In many places, it is guided to the packing material side via the thin band material and the mesh band material that comes into contact with the packing material. Therefore, the amount of liquid flowing down along the pipe wall is reduced, the thickness of the flowing liquid is reduced, the heat transfer resistance is reduced, and sufficient gas-liquid contact is performed as the amount of liquid flowing down the surface of the filler. It is possible to increase the distillation efficiency by securing the liquid amount necessary for the distillation.

That is, the thin strip acts like a scraper to separate and remove the liquid flowing down the pipe wall and transfer it to the thin strip side (however, the amount of liquid necessary to wet the pipe wall is secured. Capacity) is large, but it is difficult to fit into the shape of the outer peripheral surface of the packing (for example, thin plate regular packing),
Since the number of contact points is small, the ability to guide the liquid peeled and removed from the tube wall toward the filler is not always sufficient. In addition, the liquid transferred to the thin strip does not transfer to the packing, but reaches the lower end of the thin strip, where the vapor that rises on the packing surface flows toward the pipe wall side (rises on the packing surface). Some of the steam has a lower surface temperature than the steam and flows toward the tube wall where condensation of the steam occurs, so that the droplets may be torn off and scattered, returning to the tube wall again. There is also. On the other hand, the mesh strip does not function like a scraper, but is filled (for example, a thin-plate ordered packing).
It is easy to conform to the shape of the outer peripheral surface and comes into contact with the filler at many points, so that the ability to guide the liquid to the filler is high. Further, it is easily compatible with the thin strip, and comes into contact with the thin strip at many points. Therefore, as in the present invention, by using a combination of a thin strip and a mesh strip, the liquid can be efficiently separated and removed from the tube wall, and the liquid can be efficiently transferred to the filler side. .

[0014] As described above, the surface temperature of the tube wall is lower than that of the rising steam rising in the concentrating section.
Condensed in contact with the surface (cooling surface) of the pipe wall, the pressure in that part is lower than in other parts, and the rising steam tends to flow near the pipe wall, and as a result, the rising steam Since it flows uniformly, it becomes possible to improve the gas-liquid contact efficiency in the concentration section.

As described above, in the present invention, since the thin strip and the mesh strip are combined and used, the liquid flowing down the pipe wall is peeled off by the thin strip, and the liquid flows through the mesh strip. It is possible to efficiently guide to the structured packing side. As a result, the amount of liquid flowing down the pipe wall is reduced, the thickness of the flowing liquid is reduced, the heat transfer resistance is reduced, and the amount of liquid flowing down the surface of the packing is increased to increase the gas-liquid contact efficiency. This makes it possible to achieve a very significant effect for the internal heat exchange type distillation column, which is to improve the efficiency of gas-liquid contact in the enrichment section by making the ascending vapor flow uniformly in the enrichment section.

In the case of a structured packing used in a conventional distillation column and the like, when the column diameter of the distillation column is increased, a plurality of the structured packings are bundled and formed into a predetermined shape corresponding to the shape of the distillation column. For this reason, it has been practiced to wind a sheet strip, and it has also been practiced to provide a plurality of cuts on the side of the sheet strip on the top side of the column. It is not intended to sufficiently use the above-mentioned respective functions.
That is, in the internal heat exchange type distillation column, heat exchange is performed with the recovery unit via the tube wall of the concentration unit, and a large amount of condensate (reflux liquid) is generated on the tube wall of the concentration unit. However, realizing a configuration that can achieve the above-mentioned effects is an indispensable requirement for putting the internal heat exchange type distillation column into practical use. There is no proposal of a configuration having a sufficient function and effect.

The reason why the arrangement pitch of the cuts in the circumferential direction is set to 15 mm or less is that, in an internal heat exchange type distillation column, the diameter of a pipe (single pipe or plural pipes) is usually as small as about 300 mm. As shown in FIG. 8, when the arrangement pitch P1 of the cuts 26 of the thin plate-shaped body 22 becomes 30 mm or more,
This is because the number of portions (corners) 28a of the bent portion (cut formation portion) 28 that comes into contact with the tube wall 25a is reduced, and the efficiency of guiding the liquid flowing down the tube wall 25a to the side of the structured packing 21 is reduced.

Further, the internal heat exchange type distillation column according to claim 2 comprises:
The arrangement pitch of the mesh band and the thin plate in the height direction is 50 mm or less.

By setting the arrangement pitch in the height direction of the mesh strip and the thin strip to be 50 mm or less, the liquid flowing down the pipe wall can be thinned and the plurality of strips arranged in the height direction. Repeatedly to the structured packing side through
The amount of liquid flowing down the pipe wall is reliably reduced, the thickness of the flowing liquid is reduced, the heat transfer resistance is reduced, and the amount of liquid flowing down the surface of the packing is increased to improve gas-liquid contact efficiency. Can be improved. In addition, it is possible to improve the gas-liquid contact efficiency in the concentrating unit by allowing the rising steam rising in the concentrating unit to uniformly rise in the concentrating unit.

Further, the internal heat exchange type distillation column according to claim 3 comprises:
The distance (vertical distance from the upper side) from the upper side of the thin strip to the tip of the cut of the thin strip is 15 mm or less, and the total width of the thin strip is 3 mm.
It is characterized by being less than 0 mm.

The distance from the upper side of the thin strip to the tip (vertical distance from the upper side) of the cut of the thin strip is 15 mm or less, and the total width of the thin strip is 3 mm.
By setting the thickness to 0 mm or less, it is ensured that the entire width of the thin strip is suppressed while allowing the notch forming portion to be bent and abut on the pipe wall, and a plurality of thin strips are arranged at a dense pitch. It is possible to make the present invention more effective.

The internal heat exchange type distillation column according to claim 4 is characterized in that:
A lower end portion of the mesh strip is bent to the opposite side (filler side) to a tube wall defining at least a part of the mesh portion.

The lower end portion of the mesh strip is bent toward the opposite side (filler side) from the tube wall at least part of which defines the enrichment section, so that the liquid is further transferred to the filler side. This makes the present invention more effective.

Further, the internal heat exchange type distillation column according to claim 5 comprises:
The inside of the single tube or the plurality of tubes is a concentrating unit, and the outside of the tube is a collecting unit.

By making the inside of the tube a concentrating unit, the present invention can be constituted by using an ordered packing corresponding to the shape of the inside of the tube, which is usually cylindrical, and a practical internal heat having practicality can be obtained. It becomes possible to provide an exchange type distillation column.

[0026]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described, and features thereof will be described in detail. FIG. 1 is a front sectional view showing a main part of an internal heat exchange type distillation column according to an embodiment of the present invention, and FIG. 2 is a plan sectional view showing a main part of the internal heat exchange type distillation column. The overall configuration (basic configuration) of the internal heat exchange type distillation column is the same as that of the internal heat exchange type distillation column shown in FIGS. Therefore, the description thereof will be simplified or omitted here, and the features of the present invention will be described in detail.

In the internal heat exchange type distillation column of this embodiment, as shown in FIGS.
The outside 5 of the tube on the low pressure side serves as a recovery unit, and heat is transferred from the inside of the tube (concentration unit) 4 to the outside of the tube (collection unit) 5.

In the internal heat exchange type distillation column of this embodiment, a plurality of pipes (tubes) 25 are not shown.
Connects tubes of different diameters at a predetermined position in the height direction so that the cross-sectional area (ie, diameter) decreases stepwise from the bottom to the top so that a desired heat transfer area is secured. It is formed by doing.

In the internal heat exchange type distillation column of this embodiment, each of the inside (enrichment section) 4 and the outside (recovery section) 5 of the plurality of tubes 25 is filled with the structured packing. In addition, as the ordered packing, a metal sheet processed into a corrugated sheet, a metal sheet formed by stacking a large number of metal sheets subjected to unevenness so as not to be in close contact with each other, or a mesh material such as a wire mesh was used. In this embodiment, it is possible to use various types of metal sheets, such as corrugated metal sheets, in such a manner that the corrugated metal sheets are stacked so as not to be in close contact with each other. An ordered packing (overlaid to be radial) is used.

It is also possible to fill at least one of the inside of the tube 4 and the outside of the tube 5 with an irregular packing.
There are no particular restrictions on the types of the ordered packing and the irregular packing, and various packings can be used.

In this embodiment, the diameter is about 280.
A predetermined number of pipes having a diameter (inner diameter) of about 300 mm are arranged as pipes (plural pipes) 25 inside the main body 1 of 0 mm.
As shown in FIG. 1 and FIG. 2, a plurality of mesh bands 32 made of wire mesh are provided on the outer peripheral portion of the substantially cylindrical regular packing 21 filled in the inside (inside the tube) 4 of the tube 25 in the height direction. (Axial direction), a predetermined arrangement pitch P3 (in this embodiment, P3
3 = 42 mm) and wound in the circumferential direction.
On each mesh strip 32, a plurality of thin strips 22 made of a metal thin plate are wound. The arrangement pitch P2 of the thin strips 22 is 42 mm.

In this embodiment, the structured packing 21 is used.
In the state where the mesh band 32 is wound around the outer periphery of the thin band 22 and the thin band 22 is further wound thereon, the thin band 22 is welded from the thin band 22 to the structured packing 2 by welding.
1, the mesh strip 32 and the thin strip 22 are attached to the structured packing 21.

In this embodiment, the thin strip 22 is formed by processing a thin metal (stainless steel) sheet having a thickness of 0.1 mm, and as shown in FIG. ) W is about 22 mm and a predetermined pitch P1 (P1 = 7 mm in this embodiment) is provided on the upper side 23 of both sides 23 and 24 along the longitudinal direction in the circumferential direction.
Thus, a plurality of cuts 26 are formed.

The cut 26 is formed in a direction perpendicular to the longitudinal direction of the thin plate-shaped body 22, and its length L
1 (that is, the distance from the upper side portion 23 of the thin plate-shaped body 22 to the tip (vertical distance from the upper side portion 23) of the notch 26) is 10 mm, and the portion where the notch is not formed The distance L2 in the width direction of 27 is 12 mm. That is, in the thin plate-shaped body 22, L1 (10 mm) + L2 (12 mm) = W (22 mm).

Then, a portion (cut forming portion) 28 on the side portion 23 side where the cut 26 of the thin plate-shaped body 22 is formed.
As shown in FIG. 1, is bent outward so as to abut on a tube wall (that is, the inner wall of the tube 25) 25a that defines a region to be a concentrating unit.

The cut forming portion (bending portion) 28 of the thin plate-shaped body 22 is bent outward at a substantially right angle when wound around the structured packing 21 (ie, before being inserted into the pipe 4). By being inserted into the tube 4, the tip of the cut forming portion (bent portion) 28 is moved to the tube wall 2.
5a, and as shown in FIG.
It is configured to be about 5 °.

The mesh band 32 is formed by cutting a fine metal mesh having a coarse mesh of about 40 mesh so as to have a width Wm of 12 mm as shown in FIG. The width Wm of the mesh band 32 is
It is substantially the same as the widthwise distance L2 of the portion 27 of the thin strip 22 where the cut 26 is not formed.

As described above, on the outer periphery of the structured packing 21,
In the internal heat exchange type distillation column according to this embodiment having a configuration in which the mesh strip 32 is wound and the thin strip 22 is further wound thereon, as shown in FIG. 2, the thin strip 22 is bent. Only the two ends (corners) 28a on the distal end side of the notch forming part (bent part) 28 are the tube walls 25.
a, but the cuts 26 are formed at a small arrangement pitch P1 (7 mm pitch) in the circumferential direction,
In addition, the thin band 22 and the mesh band 32 are arranged at a small pitch (the pitch P of the thin band 22)
2 = 42 mm, arrangement pitch of the mesh band 32 P3 = 4
2 mm), the liquid flowing down the tube wall 25a migrates from many places (each end portion 28a of each bent portion 28) of the thin strip 22 to the thin strip 22, and the mesh strip is formed. Through 32, it is efficiently guided to the ordered packing 21 side.

Accordingly, the amount of liquid flowing down along the pipe wall 25a is reduced, the thickness of the flowing liquid is reduced, the heat transfer resistance is reduced, and the liquid flowing down the surface of the thin plate constituting the structured packing 21 is reduced. It is possible to improve the gas-liquid contact efficiency by increasing the amount, and further, from the side of the ordered packing 21,
It is possible to maintain the resistance of the passage of the rising steam flowing through the pipe wall 25a in a state where a sufficient amount of the rising steam can be secured.

In this embodiment, as described above,
Since the thin strip 22 having a small overall width W of 22 mm and the mesh strip 32 having a small total width Wm of 12 mm are used, it is possible to mount a large number of the thin strips 22 and the mesh strip 32 at a small arrangement pitch. That is, it is configured such that the effect of the present invention is secured.

[Performance Test] In order to confirm the performance of the internal heat exchange type distillation column having the configuration of the above embodiment, the structured packing using the thin strip and the mesh strip having the above configuration was concentrated. Heat exchange type distillation column (Example) filled in a tube which is a part, and particularly an internal heat exchange type distillation packed with a regular structured packing which does not use a thin strip and a mesh strip as described above. A performance test was performed on the column (Comparative Example) to confirm the performance of the internal heat exchange type distillation column of the present invention.

(1) Number of theoretical plates per meter of filling height (NT
SM) For the internal heat exchange type distillation columns of Comparative Examples and Examples, F-f
actor [(m / s) × (kg / m ³ ) ^0.5 ] and filling height 1
Number of theoretical stages per m NTSM (inside the tube) [stage / m]
The relationship was investigated. However, in the internal heat exchange type distillation column of the embodiment, the packed height of the structured packing 21 in the enrichment section is 1.9 m, the arrangement pitch P2 of the thin strips 22 is 42 mm, and the arrangement pitch P3 of the mesh strips 32. Is also 42 mm. In addition, F-fac
tor is a coefficient representing the load of the rising steam, and is represented by the following equation. F-factor = (steam flow rate [m / s]) × (steam density [kg /
m ³ ]) ^0.5

In this test, in the case of the internal heat exchange type distillation column of the comparative example, the number of theoretical plates NTS per 1 m of packed height was
M was about 2.5, but in the case of the internal heat exchange type distillation column of the example, the NTSM was about 3.2 to 3.7, which was higher than that of the comparative example (about 2.5). It was confirmed that the distillation separation ability was improved.

This is because, in the internal heat exchange type distillation column of the embodiment, the thin strip and the mesh strip configured as described above are used, so that a considerable amount (suitable amount) of the reflux liquid is regulated. It is considered that the amount of liquid flowing down the tube wall was suppressed from being excessively large because the liquid returned to the packing side, and the distillation separation ability was improved. In the case of the comparative example, since a considerable amount of the reflux liquid did not return to the ordered packing and flowed down the tube wall, it was considered that the distillation separation capacity was lower than that of the internal heat exchange type distillation column of the example. Can be

Further, in the internal heat exchange type distillation column of the example, no difference was observed in the distillation separation capacity (NTSM) between when the internal heat exchange was performed and when the internal heat exchange was not performed.

(2) Internal heat exchange performance (U) With respect to the internal heat exchange type distillation column having the same structure as that in the case where the above-mentioned F-factor was obtained, the flow rate of the liquid flowing down in the concentration section and the internal heat exchange performance U
The relationship of [W / m ² K] was examined. In this test, the temperature difference ΔT between the concentration section and the recovery section was set to 10 ° C.

In this test, in the case of the internal heat exchange type distillation column of the comparative example, the internal heat exchange performance U tended to decrease as the reflux amount at the top of the enrichment section increased. this is,
It is considered that the thickness of the liquid film flowing down the pipe wall increases, and the heat transfer resistance increases.

On the other hand, in the case of the internal heat exchange type distillation column according to the embodiment, the operation state of the enrichment section is changed to the case of full reflux, the product is taken out at a predetermined ratio, If the operating conditions on the side were the same, it was confirmed that the value of the internal heat exchange performance U was almost constant.

It is also known that the value of the internal heat exchange performance U can be increased by reducing the heat transfer resistance on the side of the concentrating section (condensing side) and on the side of the recovering section. This greatly contributes to reducing the heat transfer resistance on the condensing part side (condensing side).

In the above embodiment, the case where the mesh band 32 is a flat band has been described as an example.
As shown in FIG. 5, the lower end portion 32a of the mesh band 32
Is opposite to the tube wall 25a that defines the region to be the enrichment section,
That is, by making the structure bent toward the structured packing 21 side, the liquid can be more efficiently transferred to the structured packing 21 side, and the present invention can be made more effective. Note that, in FIG. 5, portions denoted by the same reference numerals as those in FIG. 1 indicate the same or corresponding portions as those in FIG.
When the lower end 32a of the mesh band 32 is bent, for example, as shown in FIG.
A notch 33 of a predetermined length L3 in the width direction from the lower end side
Is formed at a predetermined arrangement pitch P4 and is bent so that the lower end portion 32a can be easily filled with the ordered packing material 21.
The structure can be bent to the side. In the present invention, there is no particular restriction on the length L3 of the cut 33 and the arrangement pitch P4 of the cut 33,
Normally, it is desirable that L3 and P4 be 8 mm or less.

In the above embodiment, the inside of the tube is a concentrating section,
Although the case where the outside of the tube is the recovery unit has been described as an example, the present invention can also be applied to an internal heat exchange type distillation column in which the outside of the tube is a concentration unit and the inside of the tube is a recovery unit.

The present invention is not limited to the above-described embodiment in other respects, and various applications and modifications can be made within the scope of the present invention.

[0053]

As described above, the internal heat exchange type distillation column of the present invention (Claim 1) fills a region to be a concentration section (here, the case where the inside of the tube is a concentration section will be described as an example). On the outer periphery of the structured packing to be performed, a plurality of mesh bands are
In order to have a predetermined arrangement pitch in the height direction (axial direction),
The sheet band is wound in the circumferential direction, and on each mesh band, the sheet band is wound in the circumferential direction, and the upper side (tower top side) of both sides along the longitudinal direction of the sheet band. On the side, a plurality of cuts are formed at an arrangement pitch of 15 mm or less in the circumferential direction, and the side on which the cut of the thin plate-shaped body is formed defines a region to be the enrichment section. (The inner wall of the pipe), the liquid flowing down the pipe wall is efficiently separated from the pipe wall via the bent portion (bent portion) of the thin plate-shaped body. The liquid that has migrated to the thin plate-shaped body while being transferred to the thin plate-shaped object is disposed between the thin sheet-shaped material and the filling material. Therefore, it is guided to the packing material side. Therefore, the amount of liquid flowing down along the pipe wall is reduced, the thickness of the flowing liquid is reduced, the heat transfer resistance is reduced, and sufficient gas-liquid contact is performed as the amount of liquid flowing down the surface of the filler. It is possible to increase the distillation efficiency by securing the liquid amount necessary for the distillation.

When the pitch of the mesh strip and the thin strip in the height direction is set to 50 mm or less as in the internal heat exchange type distillation column of the second aspect, the liquid flowing down the pipe wall is
Repeatedly lead to the ordered packing side through the thin plate and mesh band arranged in the height direction, reduce the amount of liquid flowing down along the pipe wall, and reduce the thickness of the flowing liquid In addition, it is possible to improve the gas-liquid contact efficiency by reducing the heat transfer resistance and increasing the amount of liquid flowing down the surface of the packing. In addition, since the rising steam that rises in the enrichment section can uniformly ascend the enrichment section, the gas-liquid contact efficiency in the enrichment section can be improved, and the present invention can be made effective.

Further, as in the internal heat exchange type distillation column according to claim 3, the distance (vertical distance from the upper side) from the upper side of the thin plate to the tip of the cut is not more than 15 mm. And, when the total width of the sheet-shaped strip is set to 30 mm or less, it is ensured that the entire width of the sheet-shaped strip is reduced while allowing the notch forming portion to be bent and abut on the pipe wall. It is possible to arrange the bodies at a dense pitch, and the present invention can be made more effective.

Further, as in the internal heat exchange type distillation column according to the fourth aspect, the lower end of the mesh strip is opposite to the pipe wall defining at least a part of the enrichment section (the packing material). Side), it becomes easier to transfer the liquid to the filler side, and the present invention can be further effectively demonstrated.

In addition, as in the internal heat exchange type distillation column according to the fifth aspect, the present invention is constituted by using a regular packing corresponding to the shape of the inside of the tube, which is usually cylindrical, by forming the inside of the tube as a concentrating section. And it is possible to provide a practical internal heat exchange type distillation column having practical utility.

[Brief description of the drawings]

FIG. 1 is a front sectional view showing a main part of an internal heat exchange type distillation column according to an embodiment of the present invention.

FIG. 2 is a plan cross-sectional view showing a main part of an internal heat exchange type distillation column according to one embodiment of the present invention.

FIG. 3 is a view showing a main part of a thin plate-shaped body wound around a structured packing packed in a concentrating unit (in a pipe) in an internal heat exchange type distillation column according to an embodiment of the present invention.

FIG. 4 is a diagram showing a main part of a mesh strip wound around a structured packing filled in a concentrating unit (in a tube) in an internal heat exchange type distillation column according to one embodiment of the present invention.

FIG. 5 is a diagram showing a modification of the internal heat exchange distillation column according to one embodiment of the present invention.

6 is a diagram showing a main part of a mesh band used in the internal heat exchange type distillation column shown in FIG.

FIGS. 7A and 7B are diagrams showing a basic configuration of an internal heat exchange type distillation column, wherein FIG. 7A is a front sectional view, and FIG. 7B is a sectional view taken along line bb of FIG.

FIG. 8 is a cross-sectional plan view showing a contact state between a thin strip and a pipe wall when a thin strip used for a conventional structured packing is used.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Main body 3a Upper tube sheet (top tube sheet) 3b Lower tube sheet (tower tube sheet) 4 Inside pipe (concentrating section) 5 Outside pipe (recovering section) 6 Recovery section liquid inlet 7 Recovery section steam outlet 8 Concentrating section liquid inlet 9 Concentrating section vapor outlet 10 Recovery section vapor inlet 11 Recovery section liquid outlet 12 Concentrating section vapor inlet 13 Concentrating section liquid outlet 14a, 14b End chamber 21 Ordered packing 22 Thin strip 23, 24 Both sides of thin strip Part 25 Pipes (plural pipes) 25a Pipe wall (inner wall of pipe) 26 Cuts 27 Part of sheet strip where cut is not formed 28 Cut forming part (bent part) of sheet strip 28a Both ends of tip of cut forming part (Corner) 32 Mesh strip 32a Lower end of mesh strip 33 Cut into mesh strip L1 Cut length (vertical distance from upper side) L2 Section where cut is not formed Minute width direction distance L3 Length of cut in mesh strip P1 Pitch of cut in circumferential direction P2 Layout pitch of thin strip in height P3 Layout of mesh strip in height Pitch P4 Circumferentially arranged pitch of cut into mesh band W W Width of sheet band (full width) Wm Width of mesh band (full width)

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Toshinari Nakanishi 2-1-2, Kuisejijima, Amagasaki City, Hyogo Prefecture Inside Kimura Kakoki Co., Ltd. (72) Inventor Hideo Noda 2-97-7 Minami-Nanamatsucho, Amagasaki City, Hyogo No. Kansai Chemical Machinery Co., Ltd. (72) Inventor Takao Nakamura 2-25-10 Hatchobori, Chuo-ku, Tokyo Maruzen Petrochemical Co., Ltd. (56) References JP-A-8-66601 (JP, A) Patent 3085304 (JP, B1) (58) Fields investigated (Int. Cl. ⁷ , DB name) B01D 3/00-3/42

Claims (5)

(57) [Claims] 1. A structure in which a single pipe or a plurality of pipes is connected to a main body by means of a tube plate at both ends, so that the inside of the main body is separated from the outside of the single pipe or the plurality of pipes. In each case, a gas-liquid inlet and outlet are provided, and the operating temperature is made different by making the operating pressure different between the inside and outside of the pipe, and the pipe wall of a single pipe or multiple pipes is used as a heat transfer surface, from the high pressure side to the low pressure side An internal heat exchange type distillation column configured so that the high-pressure side functions as a concentrating section and the low-pressure side functions as a collecting section by heat transfer. The packed area (inside or outside the tube) is filled with structured packing. A plurality of mesh strips are wound around the outer periphery of the structured packing at a predetermined arrangement pitch in the height direction (axial direction) in the circumferential direction, and on each mesh strip, When the thin strip is wound in the circumferential direction A plurality of cuts are formed at an arrangement pitch of 15 mm or less in a circumferential direction on an upper side portion of both side portions along a longitudinal direction of the thin plate-shaped body, and An internal heat exchange type distillation column, characterized in that a side portion where the cut is formed is bent so that at least a part thereof abuts on a tube wall defining an area to be the enrichment section. 2. The internal heat exchange type distillation column according to claim 1, wherein the arrangement pitch of the mesh strip and the thin strip in the height direction is 50 mm or less. 3. A distance (vertical distance from an upper side) from an upper side of the thin strip to a tip of the cut of the thin strip is 15 mm or less, and the cut of the thin strip is formed. 3. The internal heat exchange type distillation column according to claim 1, wherein the total width is 30 mm or less. 4. The mesh belt-like body is characterized in that at least a part thereof is bent to the opposite side (filler side) from a tube wall defining a region to be the concentrating part. Item 4. The internal heat exchange type distillation column according to any one of Items 1 to 3. 5. A concentrating unit in the single tube or a plurality of tubes,
The internal heat exchange type distillation column according to any one of claims 1 to 4, wherein the outside of the tube is a recovery section.