Distillation Apparatus

Abstract

In order to provide a distillation device that exhibits increased component-separation efficiency relative to conventional technology, a distillation device 400 is provided with at least one distillation column including a gas-liquid contact device 440, and a cylindrical peripheral wall 432 that accommodates the at least one distillation column, wherein the gas-liquid contact device 440 causes a treatment liquid that is flowing along the distillation column in the axial direction to flow in the circumferential direction of the peripheral wall 432 and undergo gas-liquid contact with a treatment gas. This configuration increases the component-separation efficiency.

Description

[Technical field]

[0001] The present invention relates to trays for distillation and vapor-liquid contactor systems. [Background technology]

[0002] Conventionally, there is known a distillation apparatus for separating each component from a raw solution containing multiple components. The distillation apparatus separates desired components from the raw solution by contacting the raw solution with a high-temperature gas inside the apparatus (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 09-299701 Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the present invention is to provide a distillation apparatus capable of increasing the efficiency of component separation in such a distillation apparatus as compared with the prior art.

[0005] In order to solve the above problems, the present invention comprises at least one distillation column including a gas-liquid contactor, and a cylindrical peripheral wall that houses the at least one distillation column, and the gas-liquid contactor causes a treatment liquid that has flowed along the axial direction of the distillation column to flow in the circumferential direction of the peripheral wall, thereby bringing the treatment liquid into gas-liquid contact with the treatment gas. Effect of the Invention

[0006] This configuration allows the efficiency of component separation to be increased compared to the prior art. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a schematic diagram of a distillation apparatus according to a first embodiment. [Diagram 2] FIG. [Diagram 3] FIG. [Figure 4] FIG. [Diagram 5] FIG. [Figure 6] FIG. [Figure 7] FIG. 4 is a cross-sectional view of a distillation apparatus according to a modified example of the first embodiment. [Figure 8] FIG. 4 is a cross-sectional view of a distillation apparatus according to a modified example of the first embodiment. [Figure 9] FIG. 2 is a perspective view showing an example of the shape of a guide lid in the first embodiment. [Figure 10] FIG. 2 is a cross-sectional view of a distillation apparatus according to a further modified example of the first embodiment. [Figure 11] FIG. 1 is a schematic diagram of a distillation apparatus according to a second embodiment. [Figure 12] FIG. [Figure 13] FIG. [Figure 14] FIG. [Figure 15] FIG. [Figure 16] FIG. [Figure 17] FIG. 1 is a cross-sectional view of a distillation apparatus according to the prior art. [Figure 18] FIG. 1 is a cross-sectional view of a distillation apparatus according to the prior art. [Figure 19] FIG. 1 is a cross-sectional view of a distillation apparatus according to the prior art. [Figure 20] 1 shows the concentration gradient of component M5 in the gas phase in a distillation apparatus according to the prior art. [Figure 21] FIG. 4 is a cross-sectional view of a distillation apparatus according to a second embodiment. [Figure 22] FIG. [Diagram 23] FIG. [Figure 24] The concentration gradient of component M5 in the gas phase in the same distillation apparatus is shown. [Diagram 25]FIG. 11 is a perspective view of a distillation apparatus according to a modified example of the second embodiment. [Figure 26] FIG. 11 is a perspective view of a distillation apparatus according to a further modified example of the second embodiment. [Figure 27] FIG. 11 is a cross-sectional view of a distillation apparatus according to a modified example of the second embodiment. [Figure 28] FIG. 11 is a cross-sectional view of a distillation apparatus according to a further modified example of the second embodiment. [Figure 29] FIG. 11 is a perspective view showing an example of the shape of a guide lid of the distillation apparatus according to the second embodiment. [Diagram 30] FIG. 11 is a perspective view of a distillation apparatus according to a modified example of the second embodiment. [Diagram 31] FIG. 11 is a cross-sectional view of a distillation apparatus according to a modified example of the second embodiment. [Diagram 32] FIG. 11 is a cross-sectional view of a distillation apparatus according to a further modified example of the second embodiment. [Diagram 33] FIG. 11 is a cross-sectional view of a distillation apparatus according to a further modified example of the second embodiment. [Diagram 34] FIG. 11 is a cross-sectional view of a distillation apparatus according to a further modified example of the second embodiment. [Diagram 35] FIG. 11 is a cross-sectional view of a distillation apparatus according to a further modified example of the second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, an embodiment of the present invention will be described. For convenience of explanation, in the description of the embodiment, three-dimensional orthogonal coordinates or terms indicating directions may be used. The Z axis of the three-dimensional orthogonal coordinates extends along the direction in which gravity acts, the +Z direction points vertically upward, and the -Z direction points vertically downward. In addition, the distillation apparatus according to the embodiment is divided by a substantially flat partition plate inside, which will be described in detail later. The ±X directions indicate the directions in which the two main surfaces of the partition plate face, and the direction in which one main surface faces is the +X direction, and the direction in which the other main surface faces is the -X direction. The Y axis extends in the width direction of the partition plate. There is no particular clear rule on how to determine the direction in which the Y axis extends.

[0009] The distillation apparatus according to the first embodiment is a vertically divided distillation column type (column-in-column type) distillation apparatus in which multiple distillation columns are arranged in one vessel. In the first embodiment, a distillation apparatus equipped with a partition plate inside is described, which can increase the gas-liquid contact cross-sectional area more than that of conventional apparatuses without increasing the size of the distillation apparatus.

[0010] A vertically divided distillation column is designed to separate the raw liquid fed into the vessel through a single raw material inlet into multiple components and to extract each component.

[0011] Fig. 1 is a schematic diagram of a distillation apparatus. As shown in Fig. 1, distillation apparatus 10 includes at least three distillation columns. In the illustrated example, distillation apparatus 10 includes first to third distillation columns D1, D2, and D3. In Fig. 1, solid arrows indicate the movement path of liquid within distillation apparatus 10, and dashed arrows indicate the movement path of gas within distillation apparatus 10.

[0012] The distillation apparatus 10 has a cylindrical distillation tower 12 that extends along the Z axis and has closed top and bottom parts. The direction in which the distillation tower 12 extends is sometimes called the axial direction. Conventionally used distillation apparatuses are composed of three towers, whereas the distillation apparatus 10 accommodates the functions of the three towers in one packed distillation tower, forming a so-called combined distillation tower. A first distillation column D1 is disposed in the middle of the axial direction of the distillation apparatus 10, a second distillation column D2 is disposed near the top of the distillation apparatus 10, and a third distillation column D3 is disposed near the bottom of the distillation apparatus 10. A condenser 14 is connected to the top side of the distillation tower 12, and a reboiler 16 is connected to the bottom side. The distillation apparatus 10 is used to separate and extract liquids rich in components M1, M2, and M3, which have different boiling points, from the raw liquid supplied.

[0013] The inside of the distillation tower 12 is divided into a first section S1 to a fourth section S4 in order from the top. The number of sections inside the distillation tower can be appropriately selected depending on the application. In each of the sections S1 to S4, packings or trays are arranged as a gas-liquid contact device for transferring material by contacting the ascending vapor with the descending liquid. As the tray, a plate having a shape conforming to the cross-sectional shape of the XY plane of the distillation tower with a countless number of holes formed on the surface can be used. The structure of the tray will be described later. As the packing, for example, structured packings formed by processing a plate-like body or a net-like body into a corrugated shape or the like and forming it into a block shape conforming to the cross-sectional shape of the XY plane of the distillation tower, or irregular packings formed by collecting a large number of solid bodies processed into ring shapes or the like can be used.

[0014] 1, the second section S2 and the third section S3 are separated by a partition plate 18 that separates the distillation column 12 into two chambers aligned along the X-axis. The second section S2 is divided into adjacent sections 2a S2a and 2b S2b, sandwiched between the partition plate 18. The third section S3 is divided into adjacent sections 3a S3a and 3b S3b, sandwiched between the partition plate 18.

[0015] The position of the partition plate 18 along the X-axis is preferably a position that passes through the center of the horizontal cross section of the distillation column 12. However, the position of the partition plate 18 along the X-axis is not limited to this, and the partition plate 18 may be appropriately shifted along the X-axis depending on the ratio of the components in the stock solution.

[0016] 1, the first distillation column D1 is composed of the 2a section S2a and the 3a section S3a, the second distillation column D2 is composed of the 1st section S1 and the 2b section S2b, and the third distillation column D3 is composed of the 3b section S3b and the 4th section S4. The upper section of each distillation column functions as a concentration section for increasing the concentration of low boiling point components, and the lower section functions as a stripping section for increasing the concentration of high boiling point components.

[0017] The distillation tower 12 is provided with a feed nozzle 20 for feeding the raw liquid into the distillation tower 12, and a side cut nozzle 22 for taking out the separated components (liquid rich in component M2 in this embodiment) to the outside of the tower. In addition, a top vapor outlet 24 and a reflux liquid inlet 26 are provided at the top of the distillation tower 12. The top vapor outlet 24 and the reflux liquid inlet 26 are connected to a condenser 14 provided outside the distillation tower 12 for cooling and liquefying a gas (gas rich in component M1 in this embodiment). The condenser 14 may be provided integrally with the distillation tower 12. In addition, a bottom outlet 28 and a bottom vapor inlet 30 are provided at the bottom of the distillation tower 12. The bottom outlet 28 and the bottom vapor inlet 30 are connected to a reboiler 16 provided outside the distillation tower 12 for heating and evaporating a liquid (liquid rich in component M3 in this embodiment). The reboiler 16 may be integral with the distillation column 12 .

[0018] The partition plate 18 divides the interior of the distillation column 12 into a plurality of sections. The partition plate 18 extends partially along the Z axis within the internal space of the distillation column 12. The +Z and -Z ends of the partition plate 18 are located within the internal space of the distillation column 12, and liquid or gas within the distillation column 12 can move around the ends of the partition plate 18 from one main surface side to the other main surface side of the partition plate 18. The ±Y end portions of the partition plate 18 are fixed to the inner surface of the peripheral wall 32 of the distillation column 12.

[0019] The distillation apparatus 10 uses packing or trays as the gas-liquid contactor, and the type of gas-liquid contactor to be disposed in which section can be appropriately selected according to the type of raw liquid. For example, packing can be used as the gas-liquid contactor above the feed nozzle 20, and a tray can be used as the gas-liquid contactor below the feed nozzle 20. This allows a tray, which is relatively easy to clean, to be disposed in a position where dirt is relatively likely to occur.

[0020] Next, the structure of the tray will be described in detail. Fig. 2 is a perspective view of the distillation apparatus. More specifically, Fig. 2 shows the 2b section S2b with a part of the peripheral wall 32 of the distillation apparatus 10 removed. The tray structure described below is applicable to the gas-liquid contact device provided facing the partition plate 18, and is also applicable to sections other than the 2b section S2b. In other words, the tray structure described below is applicable to any of the 2a section S2a, the 3a section S3a, the 2b section S2b, and the 3b section S3b.

[0021] The 2b section S2b includes a tray 40 used to bring the liquid and the gas into contact with each other. The number of trays 40 included in the 2b section S2b may be one or more. The tray 40 is formed of a thin plate having an upper surface 40u and a lower surface 40l of a substantially semicircular shape. Here, the substantially semicircular shape refers to a shape obtained by cutting a circle along a chord Ch. Therefore, the substantially semicircular shape means a semicircular shape when the chord Ch corresponds to a diameter, and means a shape consisting of a region surrounded by the arc R and the chord Ch when the chord Ch does not correspond to a diameter. Here, the case where the chord Ch does not correspond to a diameter includes both a case where the chord Ch is on the +X side of the diameter and a case where the chord Ch is on the -X side of the diameter.

[0022] The tray 40 is disposed so that its chord Ch extends along the Y-axis and its upper surface 40u and lower surface 40l are perpendicular to the main surface of the partition plate 18 and parallel to the XY plane. The chord Ch of the tray 40 is disposed so as to contact the main surface of the partition plate 18. The arc R of the tray 40 is disposed so as to contact the inner surface of the peripheral wall 32. The tray 40 is surrounded by the partition plate 18 and the peripheral wall 32 when viewed along the Z-axis, and essentially divides a space in the ±Z directions.

[0023] The upper surface 40u of the tray 40 is formed of a liquid receiving portion 42 that receives liquid flowing from the +Z direction (above), a gas-liquid contact portion 44 that is disposed adjacent to the liquid receiving portion 42 and brings the gas and liquid into gas-liquid contact, and a liquid drainage portion 46 that allows the liquid that has been brought into gas-liquid contact to flow in the -Z direction (below). The liquid is received by the liquid receiving portion 42, flows onto the upper surface of the tray 40, passes through the gas-liquid contact portion 44, and flows into the liquid drainage portion 46.

[0024] The liquid receiving portion 42 and the liquid drainage portion 46 are provided along the chord Ch. More specifically, when the upper surface 40u of the tray 40 is bisected along the X-axis (or along a line perpendicular to the main surface of the partition plate 18), the liquid receiving portion 42 is formed on one side (the +Y direction side in the example of the upper tray shown in the figure), and the liquid drainage portion 46 is formed on the other side (the -Y direction side in the example of the upper tray shown in the figure). The liquid receiving portion 42 is a substantially rectangular region that expands by a predetermined width from the chord Ch toward the +X side and extends in the Y-axis direction along the main surface of the partition plate 18. The liquid drainage portion 46 is a substantially rectangular opening that expands by a predetermined width from the chord Ch toward the +X side and extends in the Y-axis direction along the main surface of the partition plate 18. In other words, an opening of a predetermined width is provided between the tray 40 and the partition plate 18, and this opening becomes the liquid drainage portion 46.

[0025] The gas-liquid contact portion 44 is a substantially semicircular region occupying most of the upper surface 40u of the tray 40. A plurality of holes 48 penetrating from the upper surface 40u to the lower surface 40l of the tray 40 are formed in the gas-liquid contact portion 44. The size of the holes 48 is designed so that the pressure of the gas flowing from the lower surface 40l toward the upper surface 40u suppresses the flow of liquid from the upper surface 40u toward the lower surface 40l.

[0026] The tray 40 may include a weir structure 50. The weir structure 50 is provided between the gas-liquid contact section 44 and the drainage section 46, and is formed by a wall rising from the upper surface of the tray 40 in the +Z direction. By providing the weir structure 50, the liquid depth above the gas-liquid contact section 44 can be maintained. The weir structure 50 may be a single wall having the same length as the drainage section 46 along the Y axis, or may be a discontinuous wall with gaps formed intermittently along the Y axis.

[0027] A baffle plate 52 is preferably provided between the liquid receiving section 42 and the liquid drainage section 46. The baffle plate 52 prevents the liquid that has flowed into the liquid receiving section 42 from drifting when passing through the gas-liquid contact section 44, and can prevent the liquid in the liquid receiving section 42 from reaching the liquid drainage section 46 without passing through the gas-liquid contact section 44. The baffle plate 52 is provided on the upper surface 40u of the tray 40, and is a plate that extends in the +X direction from the main surface of the partition plate 18 parallel to the XZ plane. The baffle plate 52 preferably extends from the main surface of the partition plate 18 to near the center of the gas-liquid contact section 44 in the direction along the X-axis.

[0028] The length of the baffle plate 52 along the X-axis may be adjustable. In this case, an extension 54 is provided at the tip of the baffle plate 52 on the +X side. The extension 54 can be fixed at any position to the main body of the baffle plate 52 using fixing means 56 such as a screw. By adjusting the position of the extension along the X-axis and fixing the extension 54 to the main body of the baffle plate 52 at that position, the protruding length of the baffle plate 52 in the +X direction can be adjusted. This makes it possible to adjust the flow path width between the baffle plate 52 and the peripheral wall 32.

[0029] The gas-liquid contact device further includes a downcomer plate 58. The downcomer plate 58 defines a flow path 60 (hereinafter referred to as the "downcomer flow path 60") for liquid flowing from the upper tray 40 to the lower tray 40. The downcomer flow path 60 extends along the Z axis and is formed between the downcomer plate 58 and the partition plate 18 from the liquid drainage portion 46 of the upper tray 40 to the vicinity of the liquid receiving portion 42 of the lower tray 40. The downcomer plate 58 extends parallel to the partition plate 18 at a position that does not overlap with the tray 40 along the Z axis. More specifically, the downcomer plate 58 is disposed between the adjacent trays 40 along the Z axis. The radially outer end of the downcomer plate 58 is fixed to the peripheral wall 32, and the radially inner end is fixed to a vertical wall portion 62 extending from the surface of the partition plate 18 along the X axis. Therefore, the downcomer flow path 60 is formed as a closed cross section surrounded by the partition plate 18, the peripheral wall 32, the downcomer plate 58, and the vertical wall portion 62 in the XY plane. The +Z-axis end of the downcomer flow path 60 is continuous with the weir structure 50 of the tray 40, and the downcomer plate 58 is fixed to the chord Ch of the tray 40. The -Z-axis end of the downcomer plate 58 is disposed a predetermined distance away from the upper surface 40u of the lower tray 40 and opens toward the liquid receiving portion 42 of the tray 40. The liquid that has entered the drainage portion 46 after climbing over the weir structure 50 flows along the downcomer flow path 60 to the lower tray 40. It is preferable that no gas-liquid contact is performed in the downcomer flow path 60. Here, "no gas-liquid contact is performed in the downcomer flow path 60" means that the structure of the distillation apparatus 10 does not have a configuration that actively promotes gas-liquid contact in the downcomer flow path 60. That is, the downcomer flow path 60 and the space between the trays 40 are continuous. Therefore, it is substantially impossible to prevent all of the gas in the space between the trays 40 from flowing into the downcomer flow path 60. Therefore, not allowing gas-liquid contact in the downcomer flow path 60 does not mean completely preventing gas-liquid contact, but rather means not actively sending gas into the downcomer flow path 60.In order to achieve this, for example, in order to prevent gas from entering the downcomer flow passage 60, it is preferable that the liquid receiving portion 42 located directly below the downcomer flow passage 60 has a structure that does not allow gas to pass through.

[0030] The interval between the trays 40 along the Z-axis direction can be changed as appropriate depending on the type of concentrate. As an example, the trays of the 2a section S2a and the 2b section S2b adjacent along the X-axis may be disposed at the same height relative to the Z-axis or at different heights.

[0031] 3 and 4 are cross-sectional views of the distillation apparatus. More specifically, FIG. 3 is a cross-sectional view along the XY plane in a structure in which a tray 40a of the 2a section S2a and a tray 40b of the 2b section S2b adjacent to each other along the X axis are arranged at the same height with respect to the Z axis. FIG. 4 is a cross-sectional view along the XY plane showing a tray at the lower stage of the tray shown in FIG. 3. When the heights of the trays in adjacent sections are made the same, it is preferable that the downcomer channels 60a, 60b at the same height are arranged shifted with respect to the Y axis as shown in FIG. 3 and FIG. 4. In the illustrated example, the tray 40a and the downcomer plate 58a of the 2a section S2a on one side of the partition plate 18 and the tray 40b and the downcomer plate 58b of the 2b section S2b on the other side of the partition plate 18 are arranged point-symmetrically with respect to the center of the peripheral wall 32 in the XY plane. With this arrangement, the downcomer channels 60a, 60b in adjacent sections are arranged shifted with respect to each other along the Y axis, not adjacent to each other. Moreover, the trays 40a, 40b adjacent to each other along the Z axis are arranged symmetrically with respect to the X axis. Therefore, the positions of the liquid receiving portion 42 and the liquid drainage portion 46 of the trays adjacent to each other along the Z axis are reversed with respect to the Y axis.

[0032] 5 and 6 are cross-sectional views of the distillation apparatus. More specifically, FIG. 5 is a vertical cross-sectional view of the distillation apparatus seen from the +X side, and FIG. 6 is a vertical cross-sectional view of the distillation apparatus seen from the -X side. In order to make the arrangement of the downcomer flow paths 60a and 60b easier to understand, the peripheral wall 32 is omitted in FIGS. 5 and 6. As can be seen from these figures, the downcomer flow paths 60a and 60b are not adjacent to each other via the partition plate 18. In other words, the downcomer flow paths 60a and 60b are arranged so as not to overlap each other when viewed from the surface direction of the partition plate 18. This makes it difficult for heat exchange to occur between the liquid flowing through the downcomer flow path 60a and the liquid flowing through the downcomer flow path 60b. In addition, when focusing on the downcomer flow paths 60a and 60a arranged along the Z axis, the downcomer flow paths 60a and 60a are not adjacent to each other along the Z axis. Heat transfer between the liquids flowing through the downcomer channels 60a, 60b can be minimized by arranging the downcomer channels 60a, 60b so that they are not adjacent to each other via the partition plate 18. At the same time, the path through which the liquid flows, i.e., the path through which gas-liquid contact can occur, can be lengthened by shifting the downcomer channels 60a, 60a arranged along the Z axis in the Y axis direction.

[0033] Next, the operation of the distillation apparatus will be described. In the following description, it is assumed that at least the second section S2b and the third section 3Sb on the +X-axis side of the partition plate are composed of multiple trays.

[0034] When the raw liquid is supplied to the distillation apparatus 10 from the feed nozzle 20, the gas rich in the components M1 and M2 flows upward, and the liquid rich in the components M2 and M3 flows downward. In the first section S1, the gas rich in the component M1 and the liquid rich in the component M2 are separated, and the liquid rich in the component M2 flows into the second section S2b from above. In the fourth section S4, the gas rich in the component M2 and the liquid rich in the component M3 are separated, and the gas rich in the component M2 flows toward the second section S2b and the third section 3Sb. At this time, the gas rich in the component M2 flows upward through the holes 48 of the multiple trays 40 of the second section S2b and the third section 3Sb.

[0035] When liquid flows in from above, the liquid is supplied to the uppermost tray 40. When a downcomer plate 58 is provided on the upper side of the uppermost tray 40, the liquid is supplied to the liquid receiving portion 42 of the uppermost tray 40 through a downcomer flow path 60 formed by the downcomer plate 58. The liquid that reaches the upper surface of the tray 40 flows in the circumferential direction on the upper surface of the tray so as to bypass the baffle plate 52 (see arrow A in Figures 2 and 3). Gas-liquid contact occurs while the liquid flows through the gas-liquid contact portion 44 on the tray 40. When a predetermined amount or more of liquid is present on the tray 40, the liquid jumps over the weir structure 50 and flows into the downcomer flow path 60. The liquid that flows into the downcomer flow path 60 flows downward along the downcomer flow path 60 (see arrow B in Figures 2 and 5). When the liquid reaches the lower end of the downcomer flow path 60, the liquid flows onto the liquid receiving portion 42 of the lower tray 40. The liquid that has reached the liquid receiving portion 42 of the lower tray 40 flows in the circumferential direction on the upper surface of the tray 40 so as to bypass the baffle plate 52 of the lower tray 40 (see arrow C in Figs. 2 and 4). At this time, the direction in which the liquid flows (arrow C) is opposite to the circumferential direction of the distillation apparatus 10 from the direction in which the liquid flows on the upper tray (arrow A).

[0036] According to the distillation apparatus 10, the liquid is first made to flow in the axial direction, then changed direction and made to flow in the circumferential direction to cause gas-liquid contact. This makes it possible to lengthen the path through which the liquid comes into contact with the gas without increasing the size of the apparatus. In addition, by arranging the liquid receiving portion 42 and the liquid draining portion 46 side by side along the chord Ch of the tray 40, the area of ​​the gas-liquid contact portion 44 can be increased. This makes it possible to increase the number of holes 48 on the surface of the tray 40 and the area that the holes 48 occupy on the upper surface 40u of the tray 40.

[0037] Next, a modification of the first embodiment will be described.

[0038] FIG. 7 is a cross-sectional view of a distillation apparatus according to a modified example. More specifically, FIG. 7 is a cross-sectional view in the XZ plane. As shown in FIG. 7, the distillation apparatus 100 includes a rectifying section 102 between the liquid receiving section 42 and the gas-liquid contact section 44 of the tray 40. The rectifying section 102 is a rectifying plate disposed between the liquid receiving section 42 and the gas-liquid contact section 44 and rising upward from the upper surface 40u of the tray 40. The rectifying plate constituting the rectifying section 102 is a single wall having the same length as the length of the liquid receiving section 42 along the Y axis. By providing the rectifying section 102, an upward flow can be created when the liquid flows from the liquid receiving section 42 to the gas-liquid contact section 44. This makes it possible to suppress the obstruction of the liquid flow due to the resistance of the gas flow, even if the holes 48 of the gas-liquid contact section are formed up to the vicinity of the boundary between the gas-liquid contact section 44 and the liquid receiving section 42.

[0039] The distillation apparatus 100 according to the modified example also includes a deflector 104 disposed between the drainage section 46 and the partition plate 18. The deflector 104 is a plate-like member extending from the drainage section 46 to the middle of the downcomer flow path 60. The upper end of the deflector 104 is provided at a position higher than the height in the Z-axis direction at which the liquid flows from the tray 40 into the drainage section 46. The position of the lower end of the deflector 104 is not particularly limited, and is located at the middle of the downcomer flow path 60. Both ends (both ends along the Y-axis) of the deflector 104 are fixed to the peripheral wall 32 and the vertical wall portion 62, respectively. The position of the deflector 104 in the X-axis direction is preferably the center of the downcomer flow path 60. By providing such a deflector 104, the distance over which the liquid that has entered the downcomer flow path 60 splashes within the downcomer flow path 60 after climbing over the edge of the weir structure 50 can be shortened. This shortens the distance over which the liquid comes into contact with the gas in the downcomer flow passage 60, making it possible to suppress gas-liquid contact.

[0040] Fig. 8 is a cross-sectional view of a distillation apparatus according to a further modified example. More specifically, Fig. 8 is a cross-sectional view in the XZ plane. As shown in Fig. 8, in a distillation apparatus 200, a guide lid 202 is formed at the outlet of a hole 48 in the gas-liquid contact section 44 near the boundary with the liquid receiving section 42.

[0041] FIG. 9 is a perspective view showing an example of the shape of the guide lid. As shown in FIG. 9(a) and FIG. 9(b), the guide lid 202 is open toward the gas-liquid contact section 44, and the partition plate 18 side is closed. The guide lid 202 may have a roof shape whose height gradually increases from the partition plate 18 side toward the gas-liquid contact section 44 side. Also, as shown in FIG. 9(c), the guide lid 202 may have a shape in which a tongue portion 204 having a free end is formed by partially cutting the tray, and the tongue portion 204 is raised. In either case, the guide lid 202 has an inclined shape extending toward the +X direction and the +Z direction. When the gas passes through the multiple holes 48, the gas does not rise as it is, but is guided along the guide lid 202 toward the gas-liquid contact section 44 side. By providing such a guide lid 202, the gas can be prevented from moving toward the downcomer flow path 60. As a result, the holes 48 can be formed near the boundary between the gas-liquid contact section 44 and the liquid receiving section 42, and the number of holes 48 can be increased.

[0042] Fig. 10 is a cross-sectional view of a distillation apparatus according to a further modified example. More specifically, Fig. 10 is a cross-sectional view in the XZ plane. As shown in Fig. 10, the distillation apparatus 300 includes a retention structure 302 that temporarily retains liquid in the downcomer flow passage 60. The retention structure 302 is a lid member provided at the lower end of the downcomer plate 58. The lid member is provided with a plurality of holes 304 as a discharge section, which temporarily retains liquid in the downcomer flow passage 60 and allows only a certain amount of liquid to flow from the holes 304 to the liquid receiving section 42 of the tray 40. This makes it possible to make the amount of liquid flowing to the liquid receiving section 42 of the tray 40 uniform.

[0043] The retention structure 302 may be used in combination with the guide lid 202 described above. In this case, the liquid receiving section 42 is formed with a plurality of holes 306 penetrating from the upper surface to the lower surface of the tray. Above the openings of the plurality of holes 306, the guide lid 202 is formed to guide the gas flowing from below toward the gas-liquid contact section 44. By using the retention structure 302 and the guide lid 202 in combination in this way, the holes 48 through which the gas passes can be formed in the liquid receiving section 42 as well, and the number of holes 48, 306 can be increased. In this case, the holes 306 formed in the liquid receiving section 42 function as auxiliary through holes. By applying the gas to the liquid in the liquid receiving section 42 through the holes 306, the liquid can be brought into gas-liquid contact in the liquid receiving section 42.

[0044] Next, a second embodiment of the present invention will be described.

[0045] 11 is a schematic diagram of a distillation apparatus according to the second embodiment. The distillation apparatus according to the second embodiment relates to a so-called single distillation apparatus in which one concentration section and one stripping section are provided in a column.

[0046] The distillation apparatus 400 has a cylindrical distillation tower 402 that extends along the Z axis and has a closed top and bottom. The direction in which the distillation tower 402 extends is sometimes referred to as the axial direction. The top side of the distillation apparatus 400 from the axial middle functions as a concentration section D4, and the bottom side functions as a stripping section D5. The concentration section D4 and the stripping section D5 constitute one distillation column. A condenser 414 is connected to the top side of the distillation tower 402, and a reboiler 416 is connected to the bottom side. The distillation apparatus 400 is used to separate and extract liquids rich in components M4 and M5, which have different boiling points, from the raw liquid supplied.

[0047] Inside the distillation column 402, a tray 440 is disposed as a gas-liquid contactor for transferring mass by contacting the ascending vapor with the descending liquid. As the tray 440, a plate having a surface with numerous holes formed thereon and a shape conforming to the cross-sectional shape of the distillation column in the XY plane can be used. The detailed structure of the tray 440 will be described later. As a part of the gas-liquid contactor, a packing material may be used instead of the plate. As the packing material, for example, a structured packing material formed by processing a plate-like body or a net-like body into a corrugated shape or the like and forming it into a block shape conforming to the cross-sectional shape of the distillation column in the XY plane, or a structured packing material formed by assembling a large number of solid bodies processed into ring shapes or the like can be used.

[0048] The distillation column 402 is provided with a feed nozzle 420 for supplying the raw liquid into the distillation column 402. The top of the distillation column 402 is provided with an overhead vapor outlet 424 and a reflux liquid inlet 426. The overhead vapor outlet 424 and the reflux liquid inlet 426 are connected to a condenser 414 that is provided outside the distillation column 402 and that cools and liquefies a gas (gas rich in component M4 in this embodiment). The condenser 414 may be provided integrally with the distillation column 402. The bottom of the distillation column 402 is provided with a bottom outlet 428 and a bottom vapor inlet 430. The bottom outlet 428 and the bottom vapor inlet 430 are connected to a reboiler 416 that is provided outside the distillation column 402 and that heats and evaporates a liquid (liquid rich in component M5 in this embodiment). The reboiler 416 may be provided integrally with the distillation column 402.

[0049] Which type of gas-liquid contactor is to be disposed in which section, either packing or tray, can be appropriately selected according to the type of raw liquid. For example, packing can be used as the gas-liquid contactor in the concentration section D4 located above the feed nozzle 420, and trays can be used as the gas-liquid contactor in the stripping section D5 located below the feed nozzle 420. This allows trays, which are relatively easy to clean, to be disposed in positions where dirt is relatively likely to occur.

[0050] Next, the structure of the tray will be described in detail. Figure 12 is a perspective view of the distillation apparatus. More specifically, Figure 12 shows a state in which a part of the distillation apparatus 400 has been removed. The multiple arrows in Figure 12 indicate the paths along which the liquid flows.

[0051] 12, trays 440 used for contacting liquid with gas are built into distillation column 402. The number of trays 440 may be one or more. Tray 440 is formed of a thin plate having a substantially semicircular upper surface 440u and a lower surface 440l.

[0052] The tray 440 is arranged so that the chord Ch extends along the Y axis and the upper surface 440u and the lower surface 440l are parallel to the XY plane. In the illustrated example, two trays 440 are arranged so that their chords Ch are adjacent to each other, and these two trays 440 are formed in multiple stages in the distillation tower 402. When the two trays 440 are viewed from the Z-axis direction, the two trays 440 form an approximately circular shape. At this time, one tray 440 is arranged on the +X side of the chord Ch extending parallel to the Y axis, and one tray 440 is arranged on the -X side. In other words, when the distillation tower 402 is viewed from the Z-axis direction, it can be said that a layer of multiple trays 440 is formed on both sides of the two chords Ch.

[0053] A partition plate 418 is provided in the distillation column 402 between two horizontally adjacent trays 440, i.e., at a position along the chord Ch of the two trays 440. The partition plate 418 extends upward from the chord Ch and prevents liquid from passing between the two horizontally adjacent trays 440. The arc R of the tray 440 is arranged so as to contact the inner surface of the peripheral wall 432 of the distillation column 402 arranged around the tray 440. The tray 440 is surrounded by the partition plate 418 and the peripheral wall 432 when viewed from the Z-axis direction, and substantially divides the space within the distillation column 402 in the ±Z directions.

[0054] The upper surface 440u of the tray 440 is formed of a liquid receiving section 442 that receives liquid flowing from an upper tray 440 in the +Z direction (tower top side), a gas-liquid contact section 444 that is arranged adjacent to the liquid receiving section 442 and brings the gas and liquid into gas-liquid contact, and a liquid drainage section 446 that allows the liquid that has been brought into gas-liquid contact to flow toward the lower tray 440 in the -Z direction (downward). The liquid is received by the liquid receiving section 442, passes through the gas-liquid contact section 444, and flows to the liquid drainage section 446.

[0055] The liquid receiving portion 442 and the liquid drainage portion 446 are provided along the chord Ch. More specifically, when the chord Ch of the tray 440 is divided into two equal parts, the liquid receiving portion 442 is formed on one side (the +Y direction side in the example of the upper tray on the +X side of the figure), and the liquid drainage portion 446 is formed on the other side (the -Y direction side in the example of the upper tray on the +X side of the figure). The liquid receiving portion 442 is a substantially rectangular region that expands by a predetermined width from the chord Ch toward the +X side and extends in the Y-axis direction along the main surface of the partition plate 418. The liquid drainage portion 446 is a substantially rectangular opening that expands by a predetermined width from the chord Ch toward the +X side and extends parallel to the main surface of the partition plate 418. In other words, an opening of a predetermined width is provided between the tray 440 and the partition plate 418, and this opening becomes the liquid drainage portion 446.

[0056] The gas-liquid contact portion 444 is a substantially semicircular region occupying most of the upper surface 440u of the tray 440. A plurality of holes 448 penetrating from the upper surface 440u to the lower surface 440l of the tray 440 are formed in the gas-liquid contact portion 444. The size of the holes 448 is determined so that liquid does not flow from the upper surface 440u to the lower surface 440l due to the pressure of gas flowing from the lower surface 440l to the upper surface 440u.

[0057] The tray 440 may include a weir structure 450. The weir structure 450 is provided between the gas-liquid contact section 444 and the liquid drainage section 446, and is formed by a wall rising from the upper surface 440u of the tray 440 in the +Z direction. By providing the weir structure 450, the liquid depth on the gas-liquid contact section 444 can be maintained. The weir structure 450 may be a single wall having the same length as the liquid drainage section 446 along the Y axis, or may be a discontinuous wall with gaps intermittently formed along the Y axis.

[0058] A baffle plate 452 is preferably provided between the liquid receiving section 442 and the liquid draining section 446. The baffle plate 452 prevents the liquid that has flowed into the liquid receiving section 442 from flowing along a predetermined path when passing through the gas-liquid contact section 444. In other words, the baffle plate 452 functions as a guide for the liquid. The baffle plate 452 is provided on the upper surface 440u of the tray 440, and is a plate that extends from the main surface of the partition plate 418 in the ±X direction parallel to the XZ plane. The baffle plate 452 preferably extends from the main surface of the partition plate 418 to near the center of the gas-liquid contact section 444 in the direction along the X axis.

[0059] Fig. 13 is a perspective view of the distillation apparatus. As shown in Fig. 13, the length of the baffle plate 452 along the X-axis may be adjustable. In this case, an extension 454 is provided at the tip of the +X side of the baffle plate 452. The extension 454 can be fixed at any position along the X-axis to the main body of the baffle plate 452 using fixing means 456 such as a screw. By making the position of the extension 454 adjustable relative to the baffle plate 452, the protruding length of the baffle plate 452 in the +X direction can be adjusted.

[0060] Returning to FIG. 12, the distillation apparatus 400 further includes a plurality of downcomer plates 458. The downcomer plate 458 defines a flow path 460 (hereinafter referred to as the "downcomer flow path 460") that allows liquid to flow from the upper tray 440 toward the lower tray 440 and toward the opposite side in the X-axis direction across the chord Ch. The downcomer plate 458 has a pair of opposing plates 458A and 458B. One end of the pair of plates 458A and 458B in the Y-axis direction is closed, and the other end is fixed to the peripheral wall 432. Therefore, the downcomer flow path 460 is formed as a closed cross section surrounded by the peripheral wall 432, the plate 458A, and the plate 458B in the XY plane. The pair of plates 458A and 458B are arranged apart from each other in the X-axis direction. The downcomer flow path 460 is formed between the pair of plates 458A and 458B. The downcomer flow path 460 is inclined with respect to the Z axis. Assuming that the position of the partition plate 418 is the origin of the X axis, when the upper tray 440 is on the +X side and the lower tray 440 is on the -X side among the two trays 440 connected by the downcomer plate 458, the upper part of the pair of plates 458A and 458B extends toward the tower bottom on the +X side, and the lower part is inclined toward the -X side. That is, the inlet of the downcomer flow path 460 is formed on the +X side of the chord Ch, and the outlet is formed on the -X side of the chord Ch. On the other hand, when the upper tray 440 is on the -X side and the lower tray 440 is on the +X side among the two trays 440 connected by the downcomer plate 458, the upper part of the pair of plates 458A and 458B extends toward the tower bottom on the -X side, and the lower part is inclined toward the +X side. That is, the inlet of the downcomer flow passage 460 is formed on the −X side of the chord Ch, and the outlet is formed on the +X side of the chord Ch.

[0061] Since one stage is composed of two trays 440, two downcomer plates 458 and two downcomer channels 460 extending from the upper tray 440 to the lower tray 440 are provided between each stage. These two downcomer channels 460 are disposed adjacent to each other in the Y-axis direction, and cross each other to form the letter X when the distillation column 402 is viewed from the side (along the Y-axis). Such an arrangement of the downcomer channels 460 allows the space within the distillation column 402 to be used efficiently.

[0062] The inlet of the downcomer flow path 460 is continuous with the drainage section 446, and the outlet of the downcomer flow path 460 is located at a position a predetermined distance in the Z-axis direction from the liquid receiving section 442 of the lower tray 440. The liquid that has entered the drainage section 446 flows along the downcomer flow path 460 to the lower tray 440. It is preferable not to allow gas-liquid contact to occur in the downcomer flow path 460. In order to achieve this, for example, it is preferable that the liquid receiving section 442 directly below the downcomer flow path 460 has a structure that does not allow gas to pass through so that gas does not enter the downcomer flow path 460.

[0063] 14 and 15 are cross-sectional views of the distillation apparatus. Specifically, FIG. 14 is a cross-sectional view taken along the XY plane. FIG. 15 is a cross-sectional view taken along the XY plane, showing a tray below the tray shown in FIG. 14. FIG. 16 is a cross-sectional view of the distillation apparatus. Specifically, FIG. 16 is a cross-sectional view taken along the XZ plane. In FIG. 16, the tray 440 arranged on the upper side is shown in FIG. 14, and the tray 440 arranged on the lower side is shown in FIG. 15. Hereinafter, where necessary, the description of the tray on the right side in the relevant drawing may be referred to as "tray 440R", and the description of the tray on the left side may be referred to as "tray 440L".

[0064] As shown in Figures 14 to 16, the two adjacent trays 440R, 440L have a positional relationship that is rotated 180 degrees around the central axis of the distillation column 402. Therefore, the positions of the inlets and outlets of the downcomer flow paths 460 of the two trays 440 are also rotated 180 degrees. As shown in Figures 14 to 16, the liquid that enters one downcomer flow path 460 from the drainage portion 446 of the right tray 440R in the upper stage is supplied to the liquid receiving portion 442 of the left tray 440L in the lower stage. In addition, the liquid that enters the other downcomer flow path 460 from the drainage portion 446 of the upper tray 440L is supplied to the liquid receiving portion 442 of the lower tray 440R.

[0065] The operation of the distillation apparatus 400 will now be described with reference to FIG. 11 and FIGS.

[0066] Referring to FIG. 11, when the raw liquid is fed from the feed nozzle 420 to the distillation apparatus 400, the gas rich in component M4 flows upward, and the liquid rich in component M5 flows downward. The gas rich in component M4 reaches the top of the column while passing through the holes 448 of the tray 440. A part of the gas is recovered from the top vapor outlet 424, and the rest is liquefied in the condenser 414 and returned to the distillation column 402. The liquid returned to the distillation column 402 is fed to either the +X side or the -X side of the uppermost tray 440. The liquid flows toward the bottom of the column through one of the two flow paths leading from the top of the column to the bottom of the column.

[0067] Of the raw liquid supplied from the feed nozzle 420, the liquid rich in component M5 is supplied to the flow path from the middle of one of the two flow paths and flows to the bottom of the column. A portion of the liquid rich in component M5 is recovered from the bottom outlet 428 at the bottom of the column, and the remaining liquid is vaporized in the reboiler 416 and returned to the distillation column 402. The gas generated in the reboiler 416 rises toward the top of the column while passing through holes 448 in the tray 440.

[0068] 14 to 16, the liquid flowing from the top to the bottom of the tower flows along two flow paths as indicated by arrows D and E. The liquid flowing through one of the flow paths flows in the circumferential direction of the tray 440R through the tip side of the baffle plate 452 at the upper tray 440R as indicated by arrow D, and is supplied to the lower tray 440L through the downcomer flow path 460. The liquid flowing through the other flow path flows in the circumferential direction of the tray 440L through the tip side of the baffle plate 452 at the upper tray 440L as indicated by arrow E, and is supplied to the lower tray 440R through the downcomer flow path 460. In both flow paths, the liquid comes into contact with the gas rising from the bottom side of the tower at the gas-liquid contact portion 444 of the tray 440. By repeatedly performing the same process at each stage, the purity of the components taken out increases, and the components M4 and M5 with high purity can be taken out from the distillation tower 402.

[0069] Figures 17 to 19 are cross-sectional views of a distillation apparatus according to a comparative example. Specifically, Figure 17 shows a distillation apparatus according to the prior art in the same cross section as Figure 16. Figures 18 and 19 show the same cross sections as Figures 14 and 15, respectively.

[0070] As shown in Figures 17 to 19, a distillation apparatus 1000 according to the prior art has a liquid receiving section 1004 at one end of a circular tray 1002 and a liquid draining section 1006 at the opposite end. When such a distillation apparatus 1000 is used, liquid flows in the directions indicated by arrows F and G. Arrows F and G extend from one end of the tray 1002 to the other end along the diameter of the tray 1002. In other words, in the distillation apparatus 1000 according to the prior art, gas-liquid contact was performed on one tray 1002 over a distance L2 that is shorter than the diameter L1 of the tray 1002. The distance L2 corresponds to the distance from the end of the liquid receiving section 1004 on the tray center side to the end of the liquid receiving section 1004 on the center side. In a distillation apparatus with a small diameter, the distance L2 is about 60% of the diameter (i.e., L2 = 0.6L1).

[0071] FIG. 20 shows the concentration gradient of component M5 in the gas phase in a distillation apparatus according to the prior art. In the figure, the concentration gradients at points P1 to P4 on the tray 1002 in FIGS. 17 to 19 are shown. As shown in FIGS. 17 to 20, points P2 and P3 are on the same line along the Z axis, so the concentration gradient at point P2 near the drain 1006 of the upper tray 1002 and the concentration gradient at point P3 near the liquid receiving portion 1004 of the lower tray 1002 are the same. It is generally known that the amount of mass transfer between the gas phase and the liquid phase due to gas-liquid contact is affected by the difference in component concentration in the gas phase. Since the difference in gradient is small between points P2 and P3, it is considered that the amount of mass transfer is small, especially downstream of point P3.

[0072] The distillation apparatus 400 according to the second embodiment can increase the distance over which gas-liquid contact can occur and can promote mass transfer, as compared with the distillation apparatus 1000 according to the prior art. This point will be described below.

[0073] Figures 21 to 23 are cross-sectional views of a distillation apparatus according to an embodiment. Figures 21 to 23 show the same cross sections as Figures 17 to 19, respectively. Figure 24 shows the concentration of component M5 in the gas phase in a distillation apparatus according to an embodiment, and corresponds to Figure 20.

[0074] 21 to 23, the distillation apparatus 400 according to the embodiment can perform gas-liquid contact on each tray over a distance L3, which is approximately half the circumference of a circle with a diameter of L1 / 2. In other words, the distance L3 is L1π / 4 (≈0.8L1). In this way, by adopting a structure that allows liquid to flow in the circumferential direction, the distance over which gas-liquid contact can be performed on each tray can be increased.

[0075] In addition, the distillation apparatus 1000 according to the conventional technology can only perform gas-liquid contact over the distance L2 (=0.6L1) on one tray. In contrast, the distillation apparatus according to the embodiment has two trays 440 per tray, so gas-liquid contact can be performed over a distance that is substantially 2.5 times the distance L3 (=1.6L1). In other words, it can be seen that the distillation apparatus according to the embodiment has a significantly increased throughput compared to the conventional technology.

[0076] Fig. 24 also shows the concentration gradient of component M5 at points P5 to P8 in Fig. 21 to Fig. 23. Focusing on the flow path from the tray 440 on the right side in Fig. 22 to the tray 440 on the left side in Fig. 23, the concentration gradient at point P6 near the drainage portion 446 of the upper tray 440 is different from the concentration gradient at point P7 near the liquid receiving portion 442 of the lower tray 440. This difference in concentration gradient can promote mass transfer between the gas phase and the liquid phase even immediately after the liquid moves between the stages.

[0077] According to such a distillation apparatus 400, the liquid is first flowed in the axial direction, then changed in direction and flowed in the circumferential direction to perform gas-liquid contact. This allows the path through which the liquid comes into contact with the gas to be lengthened without increasing the size of the apparatus. In addition, the area of ​​the gas-liquid contact section 444 can be increased by arranging the liquid receiving section 442 and the liquid discharge section 446 side by side along the chord Ch of the tray 440. This allows the number of holes 448 on the surface of the tray 440 and the area that the holes 448 occupy on the upper surface 440u of the tray 440 to be increased, thereby increasing the overall processing capacity of the distillation apparatus 400. This tendency is particularly noticeable when the diameter of the distillation apparatus 400 is small. In other words, various components are stored inside the peripheral wall 432 of the distillation apparatus 400 in addition to the tray 440, but the size of the components is approximately the same regardless of the diameter of the distillation apparatus 400. Therefore, in a distillation apparatus 400 with a small diameter, the volume occupied by the components in the internal space of the peripheral wall 432 is large. As the volume occupied by the components increases, the number of holes 448 (not the actual number of holes 448, but the number of holes 448 that contribute to the process) decreases. By increasing the area of ​​the gas-liquid contact section 444 as in the distillation apparatus 400 and increasing the number of holes 448 that contribute to the process, the overall throughput of the distillation apparatus 400 can be increased.

[0078] In addition, in a single distillation apparatus, the vapor load tends to be low near the bottom of the column. This tendency is particularly pronounced in a distillation apparatus with a small diameter. In the distillation apparatus 400 according to the second embodiment, the distance over which vapor-liquid contact can be performed can be increased, so that stable vapor-liquid contact can be performed even at the bottom of the column, where the vapor load tends to be relatively low.

[0079] Next, a modification of the second embodiment will be described.

[0080] FIG. 25 is a perspective view of a distillation apparatus according to a modified example. As shown in FIG. 25, the distillation apparatus 500 includes a flow straightening section 502 between the liquid receiving section 442 and the gas-liquid contact section 444 of the tray 440. The flow straightening section 502 is a flow straightening plate disposed between the liquid receiving section 442 and the gas-liquid contact section 444 and rising upward from the upper surface 440u of the tray 440. The flow straightening plate forming the flow straightening section 502 is a single wall having the same length as the length of the liquid receiving section 442 along the Y axis. By providing the flow straightening section 502, an upward flow can be created when the liquid flows from the liquid receiving section 442 to the gas-liquid contact section 444. This makes it possible to suppress the obstruction of the liquid flow due to the resistance of the gas flow, even if the holes 448 of the gas-liquid contact section are formed up to the vicinity of the boundary between the gas-liquid contact section 444 and the liquid receiving section 442.

[0081] Fig. 26 is a perspective view of a distillation apparatus according to a further modified example. Also, as shown in Fig. 26, intermittent cuts may be made in the flow straightening section 502 along the Y axis. In this case, the flow straightening section 502 creates an upward flow of liquid and also functions as a dispersion structure that disperses the flow in the Y axis direction.

[0082] FIG. 27 is a cross-sectional view of a distillation apparatus according to a modification. The distillation apparatus 550 according to the modification includes a deflector 554 disposed between the plate 458A and the plate 458B. The deflector 554 is a plate-like member extending from the drainage section 446 to the middle of the downcomer flow path 460. The upper end of the deflector 554 is provided at a position higher than the height in the Z-axis direction at which the liquid flows from the tray 440 to the drainage section 446. The position of the lower end of the deflector 554 is not particularly limited, and may be anywhere in the middle of the downcomer flow path 460. Both ends (both ends along the Y-axis) of the deflector 504 are fixed to the peripheral wall 432 and the baffle plate 452 (see FIG. 12), respectively. The position of the deflector 554 in the X-axis direction is preferably the center of the downcomer flow path 460 in the X-axis direction. By providing such a deflector 504, it is possible to shorten the distance over which the liquid that has entered the downcomer flow passage 460 splashes within the downcomer flow passage 460 after climbing over the edge of the weir structure 450. This makes it possible to shorten the distance over which the liquid comes into contact with the gas within the downcomer flow passage 460.

[0083] FIG. 28 is a cross-sectional view of a distillation apparatus according to a further modified example. More specifically, FIG. 28 is a cross-sectional view in the XZ plane. As shown in FIG. 28, the distillation apparatus 600 is provided with a guide lid 602 at the outlet of a hole 448 near the boundary with the liquid receiving part 442 in the gas-liquid contact part 444. The hole 448 formed on the lower side of the guide lid 602 also functions as a diffusion through-hole that diffuses the liquid flowing from the liquid receiving part 442. In other words, when the gas penetrates the hole 448 and hits the lower surface of the guide lid 602, a gas flow is generated from the liquid receiving part 442 toward the downstream side in the flow direction of the liquid. This allows the liquid to be diffused and flow toward the downstream side.

[0084] FIG. 29 is a perspective view showing an example of the shape of the guide lid. As shown in FIG. 29(a) and FIG. 29(b), the guide lid 602 is open toward the gas-liquid contact section 444 and closed on the opposite side. The guide lid 602 may have a roof shape whose height gradually increases toward the gas-liquid contact section 444 side. Also, as shown in FIG. 29(c), the guide lid 602 may have a shape in which a tongue portion 604 having a free end is formed by partially cutting the tray, and the tongue portion 604 is raised. In either case, the guide lid 602 has an inclined shape extending toward the +X direction and the +Z direction. When the gas passes through the multiple holes 448, the gas does not rise as it is, but is guided along the guide lid 602 toward the gas-liquid contact section 444 side. By providing such a guide lid 602, the gas can be prevented from heading toward the downcomer flow path 460. As a result, the holes 448 can be formed near the boundary between the gas-liquid contact section 444 and the liquid receiving section 442, and the number of holes 448 can be increased.

[0085] FIG. 30 is a perspective view of a distillation apparatus according to a further modified example, and FIG. 31 is a cross-sectional view of the same distillation apparatus. More specifically, FIG. 31 is a cross-sectional view in the XZ plane. As shown in FIGS. 30 and 31, the distillation apparatus 700 includes a retention structure 702 that temporarily retains liquid in the downcomer flow path 460. The retention structure 702 is a lid member provided at the lower end of the downcomer plate 458. The retention structure 702 is provided with a plurality of holes 704 (corresponding to the discharge portion). The retention structure 702 temporarily retains liquid in the downcomer flow path 460, and allows only a certain amount of liquid to flow into the liquid receiving portion 442 of the tray 440. This allows the amount of liquid flowing into the liquid receiving portion 442 of the tray 440 to be uniform.

[0086] 31, the retention structure 702 and the guide lid 602 described above may be used together. In this case, the liquid receiving section 442 is formed with a plurality of holes 706 penetrating from the upper surface to the lower surface of the tray 440. Above the openings of the plurality of holes 706, the guide lid 602 is formed to guide the gas flowing from the lower side toward the gas-liquid contact section 444. By using the retention structure 702 and the guide lid 602 together in this way, the holes 706 through which the gas passes can be formed in the liquid receiving section 442 as well, and the number of holes penetrating the tray 440 can be increased. In this case, the holes 706 below the guide lid 602 also function as through-holes for diffusing discharged liquid that diffuse the liquid discharged from the holes 704 of the retention structure 702. The guide lid 602 also functions as a diffusion structure that diffuses the liquid discharged from the holes 704 of the retention structure 702. With this configuration, when the liquid hits the upper surface of the guide lid 602, the liquid spreads within the liquid receiving portion 442 and flows downstream.

[0087] 32 and 33 are cross-sectional views of a distillation apparatus according to a further modified example. FIG. 32 shows a cross-sectional view along the XY plane, and FIG. 33 shows a cross-sectional view along the XZ plane. As shown in FIG. 32 and FIG. 33, the feed nozzle 420 may be arranged so that the feed nozzle 420 is located directly above the liquid receiving section 442 when the distillation column 402 is viewed from above. The feed nozzle 420 continues to add the raw liquid while the liquid and gas are circulating in the distillation column 402, so the feed nozzle 420 corresponds to the treatment liquid adding section. In this example, the feed nozzle 420 has a plurality of outlets that discharge the raw liquid toward the column bottom side and the partition plate 418 side, and supplies the raw liquid toward the liquid receiving section 442. With this configuration, the raw liquid can be uniformly supplied along the Y axis.

[0088] 34 and 35 are cross-sectional views of a distillation apparatus according to a further modified example. FIG. 34 shows a cross-sectional view along the XZ plane. As shown in FIG. 34, the feed nozzle 420 may be disposed near the downcomer plate 458. More specifically, the feed nozzle 420 is disposed so as to supply the raw liquid toward the plate 458B, which is downstream in the direction of liquid flow, of the pair of plates 458A and 458B. The feed nozzle 420 is preferably disposed midway between the upper tray 440 and the lower tray 440 in the height direction. In the illustrated example, the feed nozzle 420 is disposed so as to supply the raw liquid toward the inclined surface of the plate 458B. The feed nozzle 420 may be disposed so as to supply the raw liquid toward the vertical surface of the plate 458B. With this configuration, the raw liquid is applied once to the surface of the plate 458B before being mixed with the liquid flow. This allows the raw liquid to be uniformly dispersed along the surface of the plate 458B, and the raw liquid can be uniformly supplied along the Y axis.

[0089] The present invention is not limited to the above-described embodiment or its modified examples, and each configuration can be modified as appropriate without departing from the spirit of the invention. [Industrial Applicability]

[0090] The present invention has industrial applicability in the field of distillation apparatus. [Explanation of symbols]

[0091] 10 distillation apparatus, 18 plate, 32 peripheral wall, 40, 40a, 40b tray, 40l lower surface, 40u upper surface, 42 part, 44 gas-liquid contact part, 46 drainage part, 48 hole, 52 baffle plate, 58, 58a, 58b downcomer plate, 60 downcomer flow path, 60 flow path, 60a, 60b downcomer flow path, 100 distillation apparatus, 102 straightening part, 104 deflector, 200 distillation apparatus, 300 distillation apparatus, 302 retention structure, 304, 306 hole, 400 distillation apparatus, 418 plate, 432 peripheral wall, 440 tray, 440 gas-liquid contact apparatus, 440L, 440R Tray, 440l lower surface, 440u upper surface, 442 portion, 444 gas-liquid contact portion, 446 liquid discharge portion, 448 hole, 452 baffle plate, 458 downcomer plate, 458A, 458B plate, 460 downcomer flow path, 460 flow path, 500 distillation apparatus, 502 straightening portion, 504 deflector, 550 distillation apparatus, 554 deflector, 600 distillation apparatus, 700 distillation apparatus, 702 retention structure

Claims

1. at least one distillation column comprising a vapor-liquid contactor; and a cylindrical peripheral wall that houses the at least one distillation column. the gas-liquid contactor causes the treatment liquid, which has flowed in the axial direction of the distillation column, to flow in the circumferential direction of the peripheral wall, so as to bring the treatment liquid into gas-liquid contact with the treatment gas; The gas-liquid contactor includes a plurality of first trays stacked in the axial direction on one side of an internal space of the peripheral wall when the peripheral wall is viewed in the axial direction, and a plurality of second trays stacked in the axial direction on the other side of the internal space of the peripheral wall; a first downcomer plate that defines a first downcomer flow path through which the treatment liquid flows from a predetermined first tray among the plurality of first trays toward the second tray located below the predetermined first tray; a second downcomer plate that defines a second downcomer flow path through which the treatment liquid flows from a predetermined second tray among the plurality of second trays toward the first tray located below the predetermined second tray; The first tray and the second tray each have an upper surface and a plurality of through holes penetrating from a lower surface to the upper surface, a portion of the treatment liquid flows along the first downcomer flow path from the first tray to the second tray located below the first tray, flows in a circumferential direction on the second tray, and comes into contact with the treatment gas passing through the plurality of through holes provided in the second tray; A distillation apparatus wherein a remaining portion of the treatment liquid flows along the second downcomer flow path from the specified second tray toward the first tray located below it, flows circumferentially above the first tray, and comes into contact with the treatment gas passing through the multiple through holes provided in the first tray.

2. 2. The distillation apparatus according to claim 1, wherein the first downcomer plate and the second downcomer plate are arranged such that the first downcomer flow path and the second downcomer flow path intersect when the first downcomer flow path and the second downcomer flow path are viewed from a side of the distillation apparatus.

3. The first tray has a liquid receiving portion that receives the treatment liquid flowing from the second downcomer flow path; a gas-liquid contact section disposed adjacent to the liquid receiving section on a downstream side in a flow direction of the treatment liquid, the gas-liquid contact section having the plurality of through holes formed therein; a drainage section disposed adjacent to the gas-liquid contact section on a downstream side in a flow direction of the treatment liquid and connected to an inlet of the first downcomer flow path; The distillation apparatus according to claim 1 or 2, further comprising: a baffle plate disposed between the liquid receiving section and the liquid draining section and provided on the upper surface of the first tray.

4. The distillation apparatus according to claim 1 , further comprising a treatment liquid adding section that adds the treatment liquid between two of the first trays that are adjacent to each other in the vertical direction among the plurality of first trays.

5. The distillation apparatus according to claim 4 , wherein the discharge port of the treated liquid adding section opens the treated liquid toward the first downcomer plate.

6. at least three distillation columns, each distillation column comprising a vapor-liquid contactor; a cylindrical peripheral wall housing the at least three distillation columns; A partition plate extending in a chord direction when the peripheral wall is viewed from the axial direction and partitioning a space within the peripheral wall, The gas-liquid contactor is a distillation apparatus in which the process liquid flowing in the axial direction along the partition plate is caused to flow in the circumferential direction of the peripheral wall so as to come into gas-liquid contact with the process gas.

7. The gas-liquid contactor includes a plurality of trays stacked along the axial direction, each having a substantially semicircular upper surface and a plurality of through holes extending from the lower surface to the upper surface; a downcomer plate that, together with the partition plate, defines a downcomer flow path through which the treatment liquid flows from an upper tray to a lower tray among the plurality of trays, 7. The distillation apparatus of claim 6, wherein the process liquid flows axially along the downcomer flow path, flows circumferentially over the generally semicircular upper surface, and contacts the process gas passing through the plurality of through holes.

8. the downcomer plates are disposed between the plurality of trays, The distillation apparatus according to claim 7 , wherein the downcomer plates arranged along the axial direction are arranged alternately with a plane perpendicular to a plane of the partition plate interposed therebetween.

9. A second gas-liquid contactor is provided on the opposite side of the partition plate to the gas-liquid contactor, The gas-liquid contactor includes a plurality of third trays stacked along the axial direction, each having a substantially semicircular upper surface and a plurality of through holes extending from the lower surface to the upper surface; a third downcomer plate that, together with the partition plate, defines a third downcomer flow path through which the treatment liquid flows from the third tray in the upper stage to the third tray in the lower stage; The second gas-liquid contactor includes a plurality of fourth trays stacked along the axial direction, each having a substantially semicircular upper surface and a plurality of through holes extending from the lower surface to the upper surface; a fourth downcomer plate that, together with the partition plate, defines a fourth downcomer flow path through which the treatment liquid flows from the fourth tray in the upper stage to the fourth tray in the lower stage; The distillation apparatus according to claim 6 , wherein the third downcomer plate and the fourth downcomer plate are arranged so as not to overlap each other when viewed from a surface direction of the partition plate.

10. The tray includes a liquid receiving portion for receiving the liquid flowing from the downcomer flow path; a gas-liquid contact portion disposed adjacent to the liquid receiving portion and having the plurality of through holes; 9. The distillation apparatus according to claim 7, further comprising: a drainage section disposed adjacent to the gas-liquid contact section and connected to an inlet of the downcomer flow path; and a baffle plate disposed on the upper surface of the tray and between the liquid receiving section and the drainage section.

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