Gas-liquid separator, and water electrolysis system

Abstract

To provide other technique for improving gas-liquid separation performance in a gas-liquid separator.SOLUTION: A gas-liquid separator, which separates gas-liquid two-phase flow into a gas phase and a liquid phase, comprises: a container body having an inlet port in which an internal space is formed and which flows a gas-liquid two-phase flow into the internal space, a gas phase outlet port which flows out the gas phase from the internal space, and a liquid outlet port which flows out the liquid phase from the internal space; and a filling part including a laminar filling layer made from a plurality of filling materials, and a supporter having a support plate which supports the filling layer from a lower side in a gravity direction. The filling part is detachably provided on the lower side in the gravity direction with respect to the inlet port and the gas phase outlet port in the container body and on the upper side in the gravity direction with respect to the liquid phase outlet port.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a gravity type gas-liquid separator.

Background Art

[0002] A gravity type gas-liquid separator is a device for separating a liquid and a gas by a density difference. In a gravity type gas-liquid separator, the separated liquid accumulates in the lower part (the lower side in the gravity direction) of the main body of the gas-liquid separator to form a liquid pool. When the gas-liquid two-phase flow flowing into the gas-liquid separator is separated and the separated liquid falls into the liquid pool, the liquid surface becomes rough and bubbles are generated in the liquid pool. The bubbles thus generated are discharged together with the liquid from the liquid outlet at the lower part of the gas-liquid separator, which causes a decrease in the gas-liquid separation performance. In order to reduce the bubbles in the discharged liquid, it is conceivable to increase the water level in the liquid pool and remove the bubbles, but there is a problem that the size of the gravity type gas-liquid separator becomes large when doing so.

[0003] In response to such problems, a technique has been proposed in which a plate-like member is provided inside the gas-liquid separator to reduce the falling speed of the liquid falling into the liquid pool and suppress the bubbles in the liquid pool (see, for example, Patent Documents 1 and 2).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, in the techniques described in the above patent documents, water may accumulate on the plate-like member, or the bubbles in the liquid phase may not be sufficiently suppressed. Therefore, other techniques for improving the gas-liquid separation performance are required.

[0006] Therefore, an object of the present disclosure is to provide another technique for improving gas-liquid separation performance in a gas-liquid separator.

Means for Solving the Problems

[0007] The present disclosure has been made to solve at least a part of the above-described problems and can be realized in the following forms.

[0008] (1) According to one aspect of the present disclosure, there is provided a gas-liquid separator that separates a gas-liquid two-phase flow into a gas phase and a liquid phase by gravity. This gas-liquid separator includes a container body having an internal space, an inlet for allowing the gas-liquid two-phase flow to flow into the internal space, a gas-phase outlet for allowing the gas phase to flow out of the internal space, and a liquid-phase outlet for allowing the liquid phase to flow out of the internal space, a packing layer formed in a layer by a plurality of packings, and a support having a support plate for supporting the packing layer from below in the gravity direction, and a packing portion including the support, the packing portion being detachably provided below the inlet and the gas-phase outlet in the container body in the gravity direction and above the liquid-phase outlet in the gravity direction.

[0009] According to this configuration, since the packing layer is provided below the inlet and the gas-phase outlet in the container body in the gravity direction and above the liquid-phase outlet in the gravity direction, the liquid is separated from the gas-liquid two-phase flow flowing in from the inlet by gravity, and the liquid passes through the packing layer. When the liquid passes through the packing layer, its momentum is reduced, so that the speed at which the liquid falls into the liquid pool accumulated in the container body is decreased, and the generation of bubbles in the liquid pool can be suppressed. As a result, the gas-liquid separation performance can be improved.

[0010] Also, according to this configuration, since the filling part is detachably provided in the container body, the filling part can be provided as necessary depending on usage conditions and the like. That is, when sufficient gas-liquid separation performance can be obtained even without the filling part, the pressure loss can be suppressed by not providing the filling part. When necessary, the gas-liquid separation performance can be improved by attaching the filling part.

[0011] (2) The gas-liquid separator according to the above aspect, wherein the packing layer has a thickness of 90 mm or more, and the liquid phase liquid level may be arranged in the packing layer. By setting the thickness of the packing layer in this way, the generation of bubbles in the liquid pool can be further suppressed. Further, since the packing layer is arranged such that the liquid level is located in the packing layer, the falling speed of the liquid can be reduced and the disturbance of the liquid level can be suppressed. Therefore, it is possible to suppress the entrainment of gas when the separated liquid falls, and further suppress the generation of bubbles in the liquid pool. Therefore, the gas-liquid separation performance can be further improved.

[0012] (3) The gas-liquid separator according to the above aspect, wherein the size of the packing and the thickness of the packing layer satisfy (ΔP1 + ΔP2) ≤ 50 Pa, where ΔP1 is the pressure loss in the packing layer and ΔP2 is the pressure loss in the support. In this way, it is possible to suppress the retention of the liquid phase on the packing layer and suppress the bubbles in the liquid pool.

[0013] (4) The gas-liquid separator according to the above aspect, wherein the support plate has a plurality of holes, the diameter of the circumcircle of each of the plurality of holes is shorter than the minimum length of the packing, and the porosity of the support plate satisfies (ΔP1 + ΔP2) ≤ 50 Pa, where ΔP1 is the pressure loss in the packing layer and ΔP2 is the pressure loss in the support. In this way, it is possible to suppress the retention of the liquid phase on the packing layer and suppress the bubbles in the liquid pool.

[0014] (5) According to another aspect of the present disclosure, there is provided a water electrolysis system having the gas-liquid separator and the water electrolysis device of the above aspect. In this water electrolysis system, the gas-liquid separator is connected to the water electrolysis device and separates the gas and water generated by the water electrolysis device.

[0015] According to this configuration, since the gas-liquid separator is in the above aspect and the gas-liquid separation performance is improved, the hydrogen generation efficiency in the water electrolysis device can be improved.

[0016] Note that the present disclosure can be realized in various aspects, for example, in the form of a carbon dioxide electrolysis system including a carbon dioxide electrolysis device and a gas-liquid separator, a co-electrolysis system including a co-electrolysis device and a gas-liquid separator, and the like.

Brief Description of the Drawings

[0017]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Embodiments for Carrying Out the Invention

[0018] <First Embodiment> FIG. 1 is an explanatory diagram conceptually showing a cross-sectional configuration of a gas-liquid separator 100 as a first embodiment of the present disclosure. The gas-liquid separator 100 separates a gas-liquid two-phase flow into a gas phase (gas) and a liquid phase (liquid) by gravity. As shown in the figure, the gas-liquid separator 100 includes a container body 10 in which an internal space V into which the gas-liquid two-phase flow flows is formed, and a packing portion 20 detachably provided in the container body 10.

[0019] The container body 10 is formed in a substantially cylindrical shape by an upper surface 17 having a substantially circular planar shape, a bottom surface 18 having a planar shape substantially the same as that of the upper surface 17, and a side surface 19 connecting the upper surface 17 and the bottom surface 18. In the container body 10, an inlet 12 for allowing the gas-liquid two-phase flow to flow into the internal space V and a gas-phase outlet 14 for allowing the gas phase to flow out from the internal space V are formed on the side surface 19, and a liquid-phase outlet 16 for allowing the liquid phase to flow out from the internal space V is formed on the bottom surface 18. The gas-liquid separator 100 is arranged such that the bottom surface 18 is substantially directly below the upper surface 17 in the gravitational direction. The upper surface 17 of the container body 10 is detachably formed.

[0020] The packing portion 20 includes a packing layer 22 formed in a layer by a plurality of packings 21, and a support 24 that supports the packing layer 22 from below in the gravitational direction. The thickness of the packing layer 22 is not particularly limited, but for example, 50 mm or more is preferable, and 90 mm or more is more preferable. When the thickness of the packing layer 22 is 90 mm or more, when the liquid phase is water, bubbles in the liquid flowing out from the liquid-phase outlet 16 can be significantly suppressed.

[0021] FIG. 2 is an explanatory diagram schematically showing an example of the outer shapes of the packing 21 and the support plate 26. As shown in FIG. 2(A), the packing 21 of the present embodiment has a cylindrical shape. As the packing 21, for example, Raschig rings can be used. The packing 21 is not limited to a cylindrical shape, but a shape in which voids are formed when packed in the container body 10, such as a spherical shape or an oblong spherical shape, is preferable. For example, Dixon packing or the like may be used. The packing 21 is preferably formed of glass, metal, or the like.

[0022] The size of the packing 21, the porosity of the packing 21, and the thickness of the packing layer 22 are preferably determined so that no liquid stays on the packing layer 22. Specifically, they are determined so that the pressure loss when the liquid passes through the packing layer 22 is smaller than a predetermined value. This will be described in detail later.

[0023] The support 24 has a disc-shaped support plate 26 and legs 28 that support the support plate 26. The packing portion 20 is provided below the inflow port 12 and the gas-phase outlet 14 in the container body 10 in the gravitational direction and above the liquid-phase outlet 16 in the gravitational direction. The internal space V of the container body 10 is divided by the packing portion 20, and the container body 10 has a first space V1 above the gravitational direction and a second space V2 above the gravitational direction.

[0024] In the present embodiment, the support plate 26 is a wire mesh. In FIG. 2(B), as an example, a welded wire mesh (wire mesh) in which vertical lines and horizontal lines are arranged at right angles is shown. The support plate 26 may be a diamond wire mesh. The wire mesh is not limited to the welded wire mesh, and various wire meshes such as woven wire meshes can be used. The support plate 26 is not limited to the wire mesh, and various plates having holes, such as perforated metal and honeycomb structures, can be used. Furthermore, a plate having no holes may be used. When the support plate 26 has no holes, a gap may be provided between the side surface 19 of the container body 10 and the support plate 26 so that the liquid drops from the gap.

[0025] In the present embodiment, when the diameter of the packing 21 is L1 and the height is L2 (FIG. 2(A)), L1 < L2. That is, the minimum length of the packing 21 in the present embodiment is L1. On the other hand, the diameter R of the circumscribed circle C of the hole 27 of the support plate 26 (FIG. 2(B)) is shorter than the diameter L1 of the packing 21. That is, the diameter R of the circumscribed circle C of the hole 27 of the support plate 26 is shorter than the minimum length of the packing 21. Therefore, the packing 21 does not fall into the second space V2 from the hole 27 of the support plate 26 and is placed on the support plate 26.

[0026] When the support plate 26 is a diamond-shaped wire mesh, the diameter of the circumscribed circle passing through both ends of the long diagonal among the diagonals of the diamond shape is shorter than the minimum length of the packing 21.

[0027] As described above, the packing portion 20 is detachable within the container body 10. When providing the packing portion 20 within the container body 10, for example, the upper surface 17 of the container body 10 is opened (removed), the support 24 is inserted through the upper opening of the container body 10, and then a plurality of packings 21 are scattered from the upper opening of the container body 10. Thereby, a plurality of packings 21 are stacked on the support plate 26 of the support 24, and a packing layer 22 formed in a layer by the plurality of packings 21 is formed. After the packing layer 22 is formed, when the upper surface 17 of the container body 10 is closed, the gas-liquid separator 100 (FIG. 1) is completed.

[0028] As shown in FIG. 1, when the gas-liquid two-phase flow flows into the container body 10 through the inlet 12, it is separated into gas and liquid by gravity. The gas flows out of the container body 10 through the gas-phase outlet 14, and the liquid falls in the direction of gravity (the +Z-axis direction) and flows out of the container body 10 through the liquid-phase outlet 16.

[0029] The liquid separated from the gas-liquid two-phase flow passes through the gaps between the packings 21 in the packing layer 22 and the through-holes of the packing 21, passes through the holes 27 (FIG. 2) of the support plate 26, and falls into the second space V2. At this time, the momentum of the liquid is reduced by the collision with the packing 21 and the friction with the packing 21 and the support plate 26, and the falling speed is reduced.

[0030] FIG. 3 is an explanatory diagram conceptually showing the usage state of the gas-liquid separator 100. The liquid separated from the gas-liquid two-phase flow that has flowed into the container main body 10 from the inlet 12 of the gas-liquid separator 100 falls in the direction of gravity and accumulates, forming a liquid pool LP. In the present embodiment shown in FIG. 3, the liquid surface LS of the liquid pool LP is located in the packing layer 22. Based on the flow rate of the gas-liquid two-phase flow, the flow rate of the liquid flowing out from the liquid-phase outlet 16, the capacity of the second space V2, etc., the thickness of the packing layer 22 is adjusted so that the liquid surface LS of the liquid pool LP is located in the packing layer 22. As described above, the thickness of the packing layer 22 can be adjusted by the number (amount) of the packing 21 placed on the support plate 26. Note that the flow rate of the gas-liquid two-phase flow can be adjusted by a valve (not shown) provided in the pipe connected to the inlet 12. Similarly, the flow rate of the liquid can be adjusted by a valve (not shown) provided in the pipe connected to the liquid-phase outlet 16.

[0031] [Consideration of the Thickness of the Packing Layer 22] FIG. 4 is an explanatory diagram conceptually showing the difference in the bubble suppression effect depending on the thickness of the packing layer 22. FIG. 4 is created based on the experimental results. The thickness of the packing layer 22 of the gas-liquid separator 100 shown in FIG. 4(A) is t1, and the thickness of the packing layer 22 of the gas-liquid separator 100 shown in FIG. 4(B) is t2 (<t1). The two gas-liquid separators 100 are the same except that the thickness of the packing layer 22 is different.

[0032] In the example shown in FIG. 4, t1 = 90 mm and t2 = 50 mm. Also, in the gas-liquid separator 100, the height H from the bottom surface 18 of the container main body 10 to the lower end of the inlet 12 is 480 mm. The diameter of the bottom surface 18 of the container main body 10 is 204 mm. As shown in the figure, the thicker the packing layer 22, the more the generation of bubbles in the broken line portion AR of the liquid pool LP can be suppressed. This is presumably because the thicker the packing layer 22, the greater the reduction in the momentum of the falling liquid.

[0033] Figure 4 shows the results of experiments using a gas-liquid two-phase flow in which the gas phase is oxygen and the liquid phase is water. When the liquid phase is water, even when the thickness of the packing layer 22 was 50 mm, the generation of bubbles in the broken line portion AR of the liquid pool LP could be suppressed. When the thickness of the packing layer 22 was 90 mm or more, the generation of bubbles in the broken line portion AR could be significantly suppressed. From these results, it can be said that a thickness of 90 mm or more for the packing layer 22 is more preferable. The packing layer 22 is composed of a plurality of packings 21, and since the upper surface is uneven, t1 and t2 are calculated as follows. t = (height from the upper surface 17 of the container body 10 to the upper surface of the support plate 26) - (height from the upper surface 17 of the container body 10 to the lowest position of the upper surface of the packing layer 22) Here, t is the thickness of the packing layer 22.

[0034] In the example shown in Fig. 4(B), although there are more bubbles in the liquid pool than in the example shown in Fig. 4(A), the bubbles could be reduced compared to those without the packing layer 22. The bubbles in the liquid pool are entrained in the liquid and discharged from the liquid phase outlet 16, which may cause a decrease in gas-liquid separation performance. In the gas-liquid separator 100 of the present embodiment, since it has the packing portion 20, the bubbles in the liquid pool can be suppressed, and as a result, a decrease in gas-liquid separation performance can be suppressed.

[0035] [Effect of Pressure Loss] Regarding the gas-liquid separator 100 of the present embodiment shown in Fig. 4(A), the pressure loss in the packing portion 20 was determined. The pressure loss of the packing layer 22 was determined by the following (Equation 1), and the pressure loss of the support 24 was determined by the following (Equation 2).

[0036] [Equation]

[0037] [Equation]

[0038] The thickness of the packing layer 22 was 90 mm, the void fraction of the packing 21 was 92%, the diameter of the circumscribed circle of the projection view of the packing 21 was 12.7 mm, the viscosity coefficient of the liquid was 0.001005 [Pa·s], and the density of the liquid was 997 [kg / m 3 3

[0039] The support plate 26 of the support 24 is a wire mesh with an opening diameter of 10 mm (a wire mesh made by arranging vertical and horizontal wires at right angles and spot-welding the intersections), and the aperture ratio (void fraction) is 71%. The pressure loss ΔP2 of the support plate 26 obtained by the above (Equation 2) is 1.34 Pa.

[0040] Since the pressure loss ΔP in the packing section 20 is the sum of the pressure loss ΔP1 in the packing layer 22 and the pressure loss ΔP2 in the support 24, the pressure loss ΔP in the packing section 20 is 6.34 Pa.

[0041] As shown in Fig. 4(A), in the gas-liquid separator 100, no water retention was observed above the packing layer 22. In the gas-liquid separator 100, since the pressure loss in the packing section 20 is relatively small, it is considered that no liquid remained above the packing layer 22. Also, the liquid level LS of the liquid pool LP was within the packing layer 22, and the bubbles in the liquid pool LP could be sufficiently suppressed. Therefore, it can be said that the pressure loss ΔP in the packing section 20 is large enough to reduce the velocity of the falling liquid to such an extent that no bubbles are formed. That is, the pressure loss ΔP in the packing section 20 of the gas-liquid separator 100 shown in Fig. 4(A) is large enough to suppress the generation of bubbles in the liquid pool and small enough that no liquid remains above the packing section 20.

[0042] FIG. 5 is an explanatory diagram conceptually showing the usage state of the gas-liquid separator of the comparative example. FIG. 5 is also created based on the experimental results, similar to FIG. 4. The gas-liquid separator 100P1 as the first comparative example has a partition plate 26P1 instead of the packing section 20 in the gas-liquid separator 100 of the present embodiment, and the 100P2 as the second comparative example has a partition plate 26P2 instead of the packing section 20 in the gas-liquid separator 100. That is, the gas-liquid separators 100P1 and 100P2 of the comparative example do not include the packing layer 22. Further, in the gas-liquid separators 100P1 and 100P2 of the comparative example, the partition plates 26P1 and P2 are fixed in the container body 10.

[0043] The partition plate 26P1 of the gas-liquid separator 100P1 is a perforated metal with an opening diameter of 5 mm, and the opening ratio is 35%. The pressure loss ΔP2 of the partition plate 26P1 obtained by the above (Equation 1) is 123 Pa. The density of the liquid and the superficial velocity of the liquid [m / s] were calculated in the same manner as those of the above gas-liquid separator 100.

[0044] When a gas-liquid two-phase flow was introduced into the gas-liquid separator 100P1 under the same conditions as those shown in FIG. 4 and the liquid was discharged under the same conditions, as shown in FIG. 5(A), in the gas-liquid separator 100P1, the liquid level LS of the liquid pool LP was below the partition plate 26P1 in the gravitational direction, and the liquid had accumulated on the partition plate 26P1. In the gas-liquid separator 100P1, it is considered that the liquid has accumulated on the partition plate 26P1 because the pressure loss in the partition plate 26P1 is large. Also, many bubbles were formed in the liquid pool LP. Since the liquid level LS of the liquid pool LP is below the partition plate 26P1 in the gravitational direction, it is considered that when the liquid falls into the liquid pool LP, the liquid level LS becomes rough and entrains gas to form many bubbles.

[0045] The partition plate 26P2 of the gas-liquid separator 100P2 is a wire mesh with an opening diameter of 10 mm, and the opening ratio is 71%. The partition plate 26P2 is the same as the support plate 26 of the above embodiment. The pressure loss ΔP2 of the partition plate 26P2 obtained by the above (Equation 2) is 18 Pa. The density of the liquid and the superficial velocity of the liquid [m / s] were calculated in the same manner as those of the above gas-liquid separator 100.

[0046] Even in the gas-liquid separator 100P2, when a gas-liquid two-phase flow was introduced under the same conditions as those shown in FIG. 4 and the liquid was discharged under the same conditions, no liquid retention was observed on the partition plate 26P2 in the gas-liquid separator 100P2 as shown in FIG. 5(B). In the gas-liquid separator P2, since the pressure loss in the partition plate 26P2 is small, it is considered that no liquid remained on the partition plate 26P2. However, even in the gas-liquid separator 100P2, bubbles were formed in the liquid reservoir LP. In the gas-liquid separator 100P2, since the frequency of the liquid colliding with the solid in the partition plate 26P2 is low, the reduction in the momentum of the falling liquid is not sufficient, and the falling speed of the falling liquid remains relatively high. Therefore, when the liquid falls into the liquid reservoir LP, the liquid surface LS becomes rough, and it is considered that a large amount of bubbles are formed by entraining the gas.

[0047] From the above results, in the gas-liquid separator 100 of the present embodiment, when the pressure loss in the packing layer 22 is ΔP1 and the pressure loss in the support 24 is ΔP2, (ΔP1 + ΔP2) ≤ 50 Pa It is preferable that the size of the packing 21 and the thickness of the packing layer 22 satisfy this condition. By doing so, it is possible to suppress the retention of the liquid above the packing layer 22 and sufficiently suppress the generation of bubbles in the liquid reservoir SL. It is more preferable that the size of the packing 21 and the thickness of the packing layer 22 satisfy (ΔP1 + ΔP2) ≤ 45 Pa, and it is even more preferable that the size of the packing 21 and the thickness of the packing layer 22 satisfy (ΔP1 + ΔP2) ≤ 40 Pa.

[0048] Also, in the gas-liquid separator 100 of the present embodiment, the porosity of the support plate 26 is (ΔP1 + ΔP2) ≤ 50 Pa It is preferably a porosity that satisfies this. By doing so, it is possible to suppress the retention of the liquid above the packing layer 22 and, at the same time, sufficiently suppress the generation of bubbles in the liquid pool SL. It is more preferable to set the porosity to satisfy (ΔP1 + ΔP2) ≤ 45 Pa, and it is even more preferable to set the porosity to satisfy (ΔP1 + ΔP2) ≤ 40 Pa.

[0049] As described above, according to the gas-liquid separator 100 of the present embodiment, since the packing layer 22 is provided below the inlet 12 and the gas-phase outlet 14 in the container body 10 in the gravitational direction and above the liquid-phase outlet 16 in the gravitational direction, the liquid is separated from the gas-liquid two-phase flow flowing in from the inlet 12 by gravity, and the liquid passes through the packing layer. When the liquid passes through the packing layer, its momentum is reduced, so the speed at which the liquid falls into the liquid pool accumulated in the container body 10 is decreased, and the generation of bubbles in the liquid pool can be suppressed. As a result, the gas-liquid separation performance can be improved.

[0050] Moreover, according to the gas-liquid separator 100 of the present embodiment, since the packing part 20 is detachably provided in the container body 10, the packing part 20 can be provided as necessary depending on usage conditions and the like. That is, when sufficient gas-liquid separation performance can be obtained even without the packing part 20, the pressure loss can be suppressed from decreasing by not providing the packing part. When necessary, the gas-liquid separation performance can be improved by attaching the packing part.

[0051] In the gas-liquid separator 100 of the present embodiment, as described above, when the packing part 20 is provided in the container body 10, after putting the support 24 into the container body 10, a plurality of packings 21 are scattered on the support 24. As a result, a plurality of packings 21 are stacked on the support plate 26 of the support 24, and a packing layer 22 formed in a layer shape by the plurality of packings 21 is formed, so that the packing part 20 can be easily provided.

[0052] In addition, in a gravity type gas-liquid separator without the filling part 20, in order to suppress the bubbles in the liquid pool, it is conceivable to increase the water level of the liquid pool. However, there is a problem that the size of the gas-liquid separator increases when the water level of the liquid pool is increased. On the other hand, according to the gas-liquid separator 100 of the present embodiment, by providing the filling part 20, it is possible to suppress the bubbles in the liquid pool without increasing the water level of the liquid pool, so that an increase in the size of the gas-liquid separator can be suppressed.

[0053] Furthermore, in the gas-liquid separator 100 of the present embodiment, when the liquid phase is water, the thickness of the packing layer 22 is set to 90 mm or more, and the liquid level LS of the liquid pool LP by the separated liquid phase is located in the packing layer 22. When the packing layer 22 is arranged, the generation of bubbles in the liquid pool can be significantly suppressed. Therefore, the gas-liquid separation performance can be significantly improved.

[0054] In addition, in the gas-liquid separator 100 of the present embodiment, when the pressure loss in the packing layer 22 is ΔP1 and the pressure loss in the support 24 is ΔP2, (ΔP1 + ΔP2) ≤ 50 Pa By adjusting the size (size) of the packing 21, the thickness of the packing layer 22, the porosity of the support plate 26, etc. so as to satisfy the above, regardless of the type of the liquid phase, for example, even when the liquid phase is an organic solvent, the generation of bubbles in the liquid pool can be appropriately suppressed, and the gas-liquid separation performance can be improved.

[0055] <Second Embodiment> FIG. 6 is an explanatory diagram conceptually showing a cross-sectional configuration of a gas-liquid separator 100A as a second embodiment of the present disclosure. The difference between the gas-liquid separator 100A of the present embodiment and the gas-liquid separator 100 of the first embodiment is only the position of the liquid phase outlet 16. In the embodiments described below, the same components as those of the gas-liquid separator 100 of the first embodiment are denoted by the same reference numerals, and the preceding description is referred to.

[0056] In the gas-liquid separator 100A, the liquid-phase outlet 16 is provided on the lower side in the direction of gravity of the side surface 19 of the container body 10. Even in this case, the same effects as those of the gas-liquid separator 100 of the first embodiment can be obtained.

[0057] <Third Embodiment> FIG. 7 is an explanatory diagram conceptually showing a cross-sectional configuration of a gas-liquid separator 100B as a third embodiment of the present disclosure. The difference between the gas-liquid separator 100B of the present embodiment and the gas-liquid separator 100 of the first embodiment is only the positions of the inlet 12 and the gas-phase outlet 14.

[0058] In the gas-liquid separator 100B, the inlet 12 and the gas-phase outlet 14 are provided on the upper surface 17 of the container body 10. Even in this case, the same effects as those of the gas-liquid separator 100 of the first embodiment can be obtained.

[0059] <Fourth Embodiment> FIG. 8 is an explanatory diagram conceptually showing a cross-sectional configuration of a gas-liquid separator 100C as a fourth embodiment of the present disclosure. The difference between the gas-liquid separator 100C of the present embodiment and the gas-liquid separator 100 of the first embodiment is only the positions of the inlet 12, the gas-phase outlet 14, and the liquid-phase outlet 16.

[0060] In the gas-liquid separator 100C, the inlet 12 and the gas-phase outlet 14 are provided on the upper surface 17 of the container body 10. Also, the liquid-phase outlet 16 is provided on the side surface 19 of the container body 10. Even in this case, the same effects as those of the gas-liquid separator 100 of the first embodiment can be obtained. <Fifth Embodiment> FIG. 9 is an explanatory diagram conceptually showing a schematic configuration of a water electrolysis system 1000 as a fifth embodiment of the present disclosure. The water electrolysis system 1000 includes a water electrolysis device 200, the gas-liquid separator 100 of the first embodiment, a cathode-side gas-liquid separation unit 300, and a control unit 400. The gas-liquid separator 100 functions as an anode-side gas-liquid separation unit.

[0061] In the water electrolysis system 1000 of this embodiment, hydrogen is generated by electrolyzing water in the water electrolysis device 200. As shown in the figure, the water electrolysis system 1000 performs water electrolysis using electric power supplied from a power source. The power source may be grid power, or may be a power source derived from renewable energy that utilizes solar power, hydropower, wind power, wave power, biomass, geothermal heat, etc. (hereinafter also referred to as a "renewable energy source"). By using the electric power obtained from renewable energy, it is possible to synthesize clean hydrogen. The power source supplies an electric current according to an instruction from the control unit 400 to the water electrolysis device 200.

[0062] The water electrolysis device 200 is a PEM (Polymer Electrolyte Membrane) type water electrolysis device and has a membrane electrode assembly (hereinafter referred to as "MEA"). The MEA has an anode (anode) that generates oxygen from oxygen ions generated by electrolysis of water and a cathode (cathode) that generates hydrogen from hydrogen ions joined to both sides of an electrolyte membrane capable of passing hydrogen ions and water. An anode-side flow path such as a groove or pores of a porous member is formed in the anode, and a cathode-side flow path such as a groove or pores of a porous member is formed in the cathode in the same manner as the anode-side flow path. In FIG. 9, a water electrolysis stack in which a plurality of water electrolysis cells are stacked in series is shown as the water electrolysis device 200, but a single water electrolysis cell may also be used. Note that the water electrolysis device is not limited to a PEM type water electrolysis device, and other types of water electrolysis devices such as an alkaline type water electrolysis device can be used.

[0063] In the water electrolysis device 200, hydrogen (H2) and oxygen (O2) are generated by the following reactions. (Anode) H2O → 2H + + 1 / 2O2 + 2e - (Cathode) 2H + + 2e - → H2

[0064] The raw material water is supplied from the anode side, and most of the unreacted water is discharged from the anode side together with the oxygen generated at the anode. A part of the water permeates through the polymer membrane separating the anode and the cathode and is discharged from the cathode side together with hydrogen.

[0065] The gas-liquid separator 100 is connected to the anode of the water electrolysis device 200 via the anode-side discharge flow path 81. A gas-liquid two-phase flow containing oxygen generated at the anode of the water electrolysis device 200 and water that has not been electrolyzed flows into the gas-liquid separator 100 via the anode-side discharge flow path 81. The oxygen (gas) separated in the gas-liquid separator 100 is discharged to the outside via the oxygen flow path 88, and the water (liquid) is stored in the gas-liquid separator 100.

[0066] The gas-liquid separator 100 is also connected to the water electrolysis device 200 via the water supply flow path 82. As described above, the gas-liquid separator 100 stores water from which gas (mainly oxygen) has been separated from the gas-liquid two-phase flow that has flowed in from the water electrolysis device 200 via the anode-side discharge flow path 81. In addition, water is supplied to the gas-liquid separator 100 from the outside in a timely manner via the external water supply flow path 89. Since water is consumed in water electrolysis, when the amount of water stored in the gas-liquid separator 100 decreases, water is supplied from the outside via the external water supply flow path 89. The water stored in the gas-liquid separator 100 is supplied to the water electrolysis device 200 via the water supply flow path 82.

[0067] A pump 83 is provided in the water supply flow path 82. The pump 83 supplies water from the gas-liquid separator 100 to the water electrolysis device 200 according to an instruction from the control unit 400.

[0068] The cathode-side gas-liquid separator 300 is connected to the cathode side of the water electrolysis device 200 via the cathode-side flow path 91. Different from the gas-liquid separator 100, the cathode-side gas-liquid separator 300 is a gravity-type gas-liquid separator without a packing section 20. The gas-liquid two-phase flow containing hydrogen generated at the cathode of the water electrolysis device 200 and water that has not been electrolyzed flows into the cathode-side gas-liquid separator 300 via the cathode-side flow path 91. The water (liquid) from which hydrogen (gas) has been separated in the cathode-side gas-liquid separator 300 is stored in the cathode-side gas-liquid separator 300. The hydrogen separated in the cathode-side gas-liquid separator 300 is discharged to the outside via the hydrogen flow path 92. For example, a hydrogen tank (not shown) is connected to the hydrogen flow path 92, and the hydrogen generated by the water electrolysis device 200 is stored in the hydrogen tank. Further, for example, a dehydrator may be arranged on the hydrogen flow path 92.

[0069] The control unit 400 is a computer including a ROM, a RAM, and a CPU, and controls the entire water electrolysis system 1000. The control unit 400 controls the pump 83 so as to supply water corresponding to the required hydrogen production amount to the water electrolysis device 200, and controls the power supply so as to supply the current required to electrolyze the supplied water. Here, the computer includes a PLC (Programmable Logic Controller), a PC (Personal Computer), etc.

[0070] As described above, in the water electrolysis system 1000, since the gas-liquid separator 100 is connected to the anode side of the water electrolysis device 200, the amount of water flowing in is larger than that of the cathode-side gas-liquid separator 300 connected to the cathode side. Therefore, the flow rate of the liquid (water) separated from the gas-liquid two-phase flow flowing into the gas-liquid separator 100 is large. When a gas-liquid separator having the same configuration as the cathode-side gas-liquid separator 300 is used as the anode-side gas-liquid separator, bubbles are likely to be generated in the stored water (liquid pool).

[0071] In contrast, in the water electrolysis system 1000 of the present embodiment, since the gas-liquid separator 100 of the first embodiment is used as the anode-side gas-liquid separation unit, bubbles in the liquid pool can be suppressed. Therefore, when the water stored in the gas-liquid separator 100 is supplied to the water electrolysis device 200 and reused, a decrease in the hydrogen generation efficiency in the water electrolysis device 200 can be suppressed. As a result, a decrease in the energy efficiency of the water electrolysis system 1000 can be suppressed.

[0072] Further, in the gas-liquid separator 100, the filler portion 20 is detachable, and the thickness of the filler layer 22 can also be adjusted according to the amount of the filler 21. Therefore, even when the outflow timing of water from the gas-liquid separator 100 is set based on the water level of the water (liquid pool) stored in the gas-liquid separator 100, by adjusting the thickness of the filler layer 22, the liquid level of the liquid pool can be easily adjusted so as to be located in the filler layer 22. Therefore, for example, without changing the water level setting regarding the water outflow timing, generation of bubbles can be sufficiently suppressed.

[0073] Note that the gas-liquid separator 100 of the first embodiment may be used as the cathode-side gas-liquid separation unit. For example, when the configuration is such that the water stored in the cathode-side gas-liquid separation unit 300 is supplied to the gas-liquid separator 100 for electrolysis in the water electrolysis device 200, if the gas-liquid separator 100 of the first embodiment is used as the cathode-side gas-liquid separation unit, bubbles in the water to be reused can also be suppressed on the cathode side, so that a decrease in the energy efficiency of the water electrolysis system 1000 can be suppressed.

[0074] <Modification Example of the Present Embodiment> The present disclosure is not limited to the above-described embodiments, and can be implemented in various aspects without departing from the gist thereof. For example, the following modifications are possible.

[0075] ·In the above-described fifth embodiment, an example was shown in which the gas-liquid two-phase flow of oxygen (gas) and water (liquid) flowing out of the water electrolysis device is separated into gas and liquid in the gas-liquid separator 100. However, the supply source of the gas-liquid two-phase flow flowing into the gas-liquid separator 100 is not limited to the above-described embodiment. For example, as the supply source of the gas-liquid two-phase flow, other electrolysis devices such as a carbon dioxide electrolysis device and a co-electrolysis device may be used. Further, the supply source of the gas-liquid two-phase flow is not limited to an electrolysis device, and various devices that generate a gas-liquid two-phase flow can be used.

[0076] ·In the above-described embodiment, an example was shown in which the liquid pool formed by the separated liquid phase is arranged in the packing layer so that the liquid level is located. However, the position of the liquid level of the liquid pool is not limited to the above-described embodiment. For example, when the liquid level is below the packing layer in the gravitational direction, although there is some disturbance of the liquid level compared to the case where the liquid level is in the packing, the falling speed of the liquid is reduced by the packing layer, so the generation of bubbles in the liquid pool can be suppressed. When the liquid level is above the packing layer in the gravitational direction, the falling speed of the separated liquid does not change, and the disturbance of the liquid level is not suppressed. However, since the packing layer is arranged in the liquid pool, the bubbles come into contact with each other and grow as the fluid moves through the packing layer, and then move upward due to buoyancy. As a result, the bubbles in the liquid pool can be suppressed.

[0077] ·When the pressure loss in the packing layer is ΔP1 and the pressure loss in the support is ΔP2, (ΔP1 + ΔP2) may be > 50 Pa. In this case, even if the liquid stays on the packing layer, since the falling speed of the liquid decreases when the liquid passes through the packing layer, the bubbles in the liquid pool can be suppressed. However, if (ΔP1 + ΔP2) ≤ 50 Pa, the retention of the liquid above the packing layer can be suppressed, and the bubble suppression effect can be enhanced.

[0078] The present aspect has been described based on the embodiments and modified examples above. However, the embodiments of the above-described aspects are for facilitating the understanding of the present aspect and do not limit the present aspect. The present aspect can be changed and improved without departing from its spirit and the scope of the claims, and equivalents thereof are included in the present aspect. Also, if the technical features are not described as essential in this specification, they can be deleted as appropriate.

[0079] The present disclosure can also be realized in the following forms. [Application Example 1] A gas-liquid separator that separates a gas-liquid two-phase flow into a gas phase and a liquid phase by gravity, a container body having an internal space, an inlet for allowing the gas-liquid two-phase flow to flow into the internal space, a gas-phase outlet for allowing the gas phase to flow out of the internal space, and a liquid-phase outlet for allowing the liquid phase to flow out of the internal space, a packing section including a packing layer formed in a layer by a plurality of packings and a support body having a support plate for supporting the packing layer from below in the direction of gravity, comprising the packing section is detachably provided below the inlet and the gas-phase outlet in the container body in the direction of gravity and above the liquid-phase outlet in the direction of gravity, a gas-liquid separator. [Application Example 2] The gas-liquid separator according to Application Example 1, wherein the packing layer has a thickness of 90 mm or more, and is arranged such that the liquid level of the liquid pool formed by the separated liquid phase is located in the packing layer, a gas-liquid separator. [Application Example 3] The gas-liquid separator according to claim 1 or Application Example 2, wherein the size of the packing and the thickness of the packing layer when the pressure loss in the packing layer is ΔP1 and the pressure loss in the support body is ΔP2, (ΔP1 + ΔP2) ≦ 50 Pa The size of the filler and the thickness of the filler layer that satisfy Gas-liquid separator. [Application Example 4] A gas-liquid separator according to any one of Application Examples 1 to 3, The support plate has a plurality of holes, The diameter of the circumscribed circle of each of the plurality of holes is shorter than the minimum length of the filler, The porosity of the support plate is When the pressure loss in the filler layer is ΔP1 and the pressure loss in the support is ΔP2, (ΔP1 + ΔP2) ≦ 50 Pa A gas-liquid separator having a porosity that satisfies [Application Example 5] A water electrolysis system having the gas-liquid separator according to any one of Application Examples 1 to 4 and a water electrolysis device, The gas-liquid separator is connected to the water electrolysis device and separates the gas and water generated by the water electrolysis device. Water electrolysis system.

Explanation of Reference Numerals

[0080] 10... Container body 12... Inlet 14... Gas-phase outlet 16... Liquid-phase outlet 17... Upper surface 18... Bottom surface 19... Side surface 20... Filler section 21... Filler 22... Filler layer 24... Support 26... Support plate 26P1, 26P2... Partition plates 27... Holes 28... Legs 81... Anode-side discharge flow path 82... Water supply flow path 83... Pump 88... Oxygen flow path 89... External water supply flow path 91... Cathode-side flow path 92... Hydrogen flow path 100, 100A, 100B, 100C, 100P1, 100P2... Gas-liquid separator 200... Water electrolysis device 300... Cathode-side gas-liquid separation section 400... Control unit 1000... Water electrolysis system LS... Liquid level V... Internal space V1... First space V2... Second space

Claims

1. A gas-liquid separator that separates a gas-liquid two-phase flow into a gas phase and a liquid phase by gravity, having an internal space, an inlet for allowing the gas-liquid two-phase flow to flow into the internal space, a gas-phase outlet for allowing the gas phase to flow out of the internal space, and a liquid-phase outlet for allowing the liquid phase to flow out of the internal space, a packing part including a packing layer formed in layers by a plurality of packings and a support body having a support plate for supporting the packing layer from below in the gravity direction, comprising, wherein the packing part is detachably provided below the inlet and the gas-phase outlet in the gravity direction in the container body and above the liquid-phase outlet in the gravity direction, a gas-liquid separator.

2. The gas-liquid separator according to Claim 1, wherein the packing layer has a thickness of 90 mm or more, and is arranged such that the liquid level of the liquid pool formed by the separated liquid phase is located in the packing layer, a gas-liquid separator.

3. The gas-liquid separator according to Claim 1, wherein the size of the packing and the thickness of the packing layer Let the pressure loss in the filling layer be ΔP 1 and the pressure loss in the support be ΔP 2 When this is the case, (ΔP 1 + ΔP 2 ) ≤ 50 Pa satisfy, the size of the packing and the thickness of the packing layer, a gas-liquid separator.

4. The gas-liquid separator according to Claim 1, wherein the support plate has a plurality of holes, the diameter of the circumcircle of each of the plurality of holes is shorter than the minimum length of the packing, Let the pressure loss in the filler layer be ΔP 1 and the pressure loss in the support be ΔP 2 When this is the case, (ΔP 1 + ΔP 2 ) ≤ 50 Pa and the porosity of the support plate is a porosity that satisfies, a gas-liquid separator.

5. A water electrolysis system having the gas-liquid separator according to Claims 1 to 4 and a water electrolysis device, wherein the gas-liquid separator is connected to the water electrolysis device and separates the gas and water generated by the water electrolysis device, a water electrolysis system.

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