Concentrating device

Abstract

Provided is a concentration device that can obtain a concentrated liquid having a higher concentration more quickly. The concentration device of the present invention is a cross-flow type concentration device that concentrates a liquid containing a filtration target object, and includes: a liquid tank that stores the liquid; a tubular member whose both end portions are disposed in the liquid tank and forms a circulation flow path; a circulation pump that circulates the liquid stored in the liquid tank from one end portion of the tubular member to the other end portion; a filter that is provided to a side wall of the tubular member and has a metal porous membrane that filters the filtration target object; a bypass pipe that connects both end portions to the side wall of the tubular member and short-circuits the circulation flow path; a switching valve that switches so that the liquid flowing in the tubular member flows in the bypass pipe; and a control unit that controls the driving of the circulation pump and the switching operation of the switching valve.

Description

TECHNICAL FIELD

[0001] The present application relates to a concentration device of a cross-flow type that concentrates a liquid containing a filtration target. BACKGROUND

[0002] In the past, as a filtration device that filters a liquid containing a filtration target, for example, a filtration device described in Patent Literature 1 (Japanese Patent Application Publication No. 2013-210239) is known. The filtration device of Patent Literature 1 is a device that causes a liquid containing a filtration target to flow along the surface of a filter such as a hollow fiber membrane, and collects a liquid (hereinafter referred to as a filtrate) in which the filtration target has been removed by the filter.

[0003] According to such a filtration device, the liquid containing the filtration target is caused to flow along the surface of the filter, and thus the filtration target captured by the surface of the filter is released from the capture by the flow of the liquid. Thereby, it is possible to suppress clogging of the filter and continuously collect the filtrate for a longer period of time, and it is possible to improve the filtration efficiency.

[0004] In addition, with such a filtration device, the liquid containing the filtration target is caused to circulate and flow along the surface of the filter a plurality of times, and the filtrate is removed by the filter, and thus it is possible to obtain a concentrated liquid in which the concentration of the filtration target is high. Hereinafter, the filtration device for the purpose of obtaining a concentrated liquid will be referred to as a "concentration device".

[0005] PRIOR ART DOCUMENTS

[0006] PATENT LITERATURE

[0007] Patent Literature 1: Japanese Patent Application Publication No. 2013-210239 SUMMARY

[0008] PROBLEMS TO BE SOLVED BY THE INVENTION

[0009] However, in the past filtration device, there is still room for improvement in terms of obtaining a concentrated liquid in which the concentration is higher more quickly.

[0010] Therefore, an object of the present application is to provide a concentration device that can obtain a concentrated liquid in which the concentration is higher more quickly.

[0011] MEANS FOR SOLVING THE PROBLEMS

[0012] In order to achieve the object, a concentration device of one embodiment of the present application is a concentration device of a cross-flow type that concentrates a liquid containing a filtration target, and is characterized by comprising:

[0013] The concentration device comprises:

[0014] a liquid tank that accommodates the liquid;

[0015] A tubular component, with its two ends disposed inside the liquid tank, forms a circulation path;

[0016] A circulation pump that circulates the liquid contained in the liquid tank from one end of the tubular member to the other end.

[0017] A filter, disposed on the side wall of the tubular member, has a porous metal membrane for filtering the object to be filtered;

[0018] A bypass pipe, the two ends of which are connected to the sidewall of the tubular member, to short-circuit the circulation path;

[0019] A switching valve that switches the flow of liquid flowing within the tubular member to flow within the bypass pipe; and

[0020] The control unit controls the driving of the circulating pump and the switching action of the switching valve.

[0021] Invention Effects

[0022] The concentration apparatus according to the present invention can obtain a higher concentration of concentrate more quickly. Attached Figure Description

[0023] Figure 1 This is a schematic structural diagram of the concentration apparatus according to Embodiment 1 of the present invention.

[0024] Figure 2 It is shown Figure 1 A cross-sectional view of the structure near the filter of the concentration unit.

[0025] Figure 3 yes Figure 2 A magnified three-dimensional view of the metal porous membrane of the filter.

[0026] Figure 4 It is shown Figure 1 The flowchart shows the process by which a concentration device filters the object to be filtered to obtain a concentrated liquid.

[0027] Figure 5 It is shown Figure 1 A schematic diagram of the operation of a concentration device to filter the object to be filtered and obtain a concentrated liquid.

[0028] Figure 6 It shows the next step. Figure 5 A summary structure diagram of the actions being performed.

[0029] Figure 7 It shows the next step. Figure 6 A summary structure diagram of the actions being performed.

[0030] Figure 8 is a schematic configuration view of a concentration device of Embodiment 2 of the present application.

[0031] Figure 9 is a schematic configuration view of a concentration device of Embodiment 3 of the present application.

[0032] Figure 10 is a schematic configuration view of a concentration device of Embodiment 4 of the present application.

[0033] Figure 11 is a schematic configuration view of a concentration device of Embodiment 5 of the present application. DETAILED DESCRIPTION

[0034] (Insight underlying the present application)

[0035] The present inventors have conducted intensive studies in order to obtain a concentrated liquid with a higher concentration more quickly, and as a result, have arrived at the following new insight.

[0036] In obtaining a concentrated liquid using a conventional filter device, for example, it is possible to configure such that a liquid containing a filtration target object housed in a liquid tank is caused to flow in a circulation flow path by a circulation pump, the liquid is filtered by a filter provided in the circulation flow path to remove a filtrate, and the remaining liquid is returned to the liquid tank. The liquid returned to the liquid tank is caused to flow in the circulation flow path again by the circulation pump, filtered by the filter to remove a filtrate, and returned to the liquid tank. By repeating this operation, a larger amount of filtrate can be removed from the liquid containing the filtration target object, and a concentrated liquid with a higher concentration can be obtained.

[0037] In addition, in the configuration, for example, the flow rate of the liquid can be increased by increasing the output of the circulation pump, or the amount of liquid flowing in the circulation flow path can be increased by increasing the inner volume (length x opening area) of the circulation flow path, so that a concentrated liquid can be obtained more quickly.

[0038] However, for example, in the case where the filtration target object is a biological substance such as a cell, when the flow rate of the liquid is increased, the shear force and friction force received by the biological substance become large, and the stress applied to the biological substance becomes large. In addition, in the case where the circulation flow path is lengthened to increase the inner volume, the time during which the biological substance flows in the circulation flow path becomes long, and thus the stress applied to the biological substance becomes large. Therefore, there is a limit to increasing the flow rate of the liquid or lengthening the circulation flow path in order to obtain a concentrated liquid more quickly.

[0039] In addition, when the filter removes the filtrate from the liquid flowing in the circulation flow path, a foam (air bubbles mixed in the liquid) can be generated due to a decrease in the amount of liquid. When the foam is generated, for example, an adverse effect on the operation of the pump can occur, and the pressure of the liquid flowing in the circulation flow path can fluctuate greatly. The foam is easily generated when the amount of the liquid (the concentrated liquid) in the liquid tank is, for example, 2 times or less the internal volume of the circulation flow path. Therefore, when the amount of the liquid in the liquid tank is 2 times or less the internal volume of the circulation flow path, it is desirable to stop the filtration, and thus, it is difficult to obtain a concentrated liquid with a higher concentration. In particular, the more the internal volume of the circulation flow path is increased, the more the amount of the liquid in the liquid tank needs to be increased, and it is difficult to obtain a concentrated liquid with a higher concentration.

[0040] In view of the above, the present inventors have found that a bypass pipe is provided to a side wall of a tubular member that forms a circulation flow path, and a switching valve is provided that switches so that the liquid flowing in the tubular member flows in the bypass pipe. According to this structure, in the initial stage of filtration, the internal volume of the circulation flow path can be increased, and a concentrated liquid can be obtained more quickly. In addition, for example, by switching the switching valve at a timing at which a foam is generated, the circulation flow path can be short-circuited, and the internal volume of the circulation flow path can be substantially reduced. Thus, the filtration can be continued while suppressing the generation of a foam, and a concentrated liquid with a higher concentration can be obtained. Based on these new insights, the present inventors have made the following invention.

[0041] A concentration device of one embodiment of the present application is a cross-flow type concentration device that filters a liquid containing a filtration target object to obtain a concentrated liquid,

[0042] The concentration device includes:

[0043] a liquid tank that accommodates the liquid;

[0044] a tubular member whose both end portions are disposed in the liquid tank and forms a circulation flow path;

[0045] a circulation pump that circulates the liquid accommodated in the liquid tank from one end portion to the other end portion of the tubular member;

[0046] a filter that is provided to a side wall of the tubular member and has a metal-made porous membrane that filters the filtration target object;

[0047] a bypass pipe whose both end portions are connected to the side wall of the tubular member and short-circuits the circulation flow path;

[0048] a switching valve that switches so that the liquid flowing in the tubular member flows in the bypass pipe; and

[0049] a control portion that controls the driving of the circulation pump and the switching operation of the switching valve.

[0050] According to this structure, it is possible to obtain a concentrated liquid with a higher concentration more quickly.

[0051] Note that, when the remaining amount of the liquid housed in the liquid tank is equal to or less than a threshold amount, the control section can switch the switching valve so that the liquid flowing in the tubular member flows in the bypass pipe. According to this structure, it is possible to suppress the generation of foam and obtain a concentrated liquid with a higher concentration more quickly.

[0052] In addition, when the pressure or flow rate of the liquid flowing in the tubular member is equal to or less than a threshold value, the control section can switch the switching valve so that the liquid flowing in the tubular member flows in the bypass pipe. According to this structure, it is possible to suppress the generation of foam and obtain a concentrated liquid with a higher concentration more quickly.

[0053] In addition, as the filtration progresses, the concentration of the concentrated liquid flowing in the circulation flow path becomes higher, and the filtration target objects are likely to collide with other filtration target objects or the side wall of the tubular member and be pressed. Therefore, the filtration device can further include a filtrate pump that causes a portion of the liquid flowing in the tubular member to pass through the filter, and the control section can control the drive force of the filtrate pump to be reduced when the switching valve is switched so that the liquid flowing in the tubular member flows in the bypass pipe. According to this structure, it is possible to slow down the filtration speed (concentration speed) compared to the initial stage and suppress the pressing of the filtration target objects.

[0054] In addition, the bypass pipe can include a first bypass pipe and a second bypass pipe that short-circuits the circulation flow path more than the first bypass pipe, the switching valve can be configured to be switched so that the liquid flowing in the tubular member flows in the first bypass pipe or the second bypass pipe, and the control section can cause the filtrate pump to be driven at a first drive force when the switching valve is switched so that the liquid flowing in the tubular member flows in the first bypass pipe and cause the filtrate pump to be driven at a second drive force smaller than the first drive force when the switching valve is switched so that the liquid flowing in the tubular member flows in the second bypass pipe. According to this structure, it is possible to gradually (stagedly) slow down the filtration speed, obtain a concentrated liquid with a higher concentration more quickly, and suppress the pressing of the filtration target objects.

[0055] Note that, the control section can control the switching valve to be switched so that the liquid flows in the second bypass pipe for a longer time than the liquid flows in the first bypass pipe. According to this structure, it is possible to slow down the speed of the concentrated liquid flowing in the second bypass pipe, which has a higher concentration than the concentrated liquid flowing in the first bypass pipe, and further suppress the pressing of the filtration target objects.

[0056] In addition, the bypass pipe filter can be provided on the side wall of the bypass pipe and have a metal-made porous membrane that filters the filtration target. According to this structure, even if the filter is clogged, the liquid can be continuously filtered by the bypass pipe filter, and thus, a more concentrated concentrated liquid can be obtained more quickly.

[0057] In addition, the inner diameter of the bypass pipe can be smaller than the inner diameter of the tubular member. According to this structure, the inner volume of the circulation flow path can be further reduced, and a more concentrated concentrated liquid can be obtained. In addition, the filtration speed can be reduced compared to the initial stage, and the filtration target can be prevented from being pressed.

[0058] It is to be noted that, in this case, when the liquid flows from the tubular member having a large inner diameter to the bypass pipe having a small inner diameter at a position on the upstream side of the bypass pipe in the flow direction of the liquid, the flow of the liquid is hindered, and the control of the pressure of the liquid becomes difficult. Therefore, the filter is preferably provided at a position on the downstream side of the bypass pipe in the flow direction of the liquid. According to this structure, the liquid can be more stably filtered (concentrated) by the filter.

[0059] Hereinafter, an embodiment of the present application will be described with reference to the drawings. It is to be noted that the present application is not limited by this embodiment.

[0060] (Embodiment 1)

[0061] The concentration device of the present embodiment 1 is a cross-flow type concentration device that filters a liquid containing a filtration target to obtain a concentrated liquid. Figure 1 is a schematic configuration view of the concentration device of the present embodiment 1.

[0062] As Figure 1 shown, the concentration device 1 of the present embodiment 1 includes a liquid tank 2 and a tubular member 3.

[0063] The liquid tank 2 is a container that stores a liquid 12 containing a filtration target 11. As Figure 1 shown, the liquid tank 2 can be an open-top container or a closed container.

[0064] In the present embodiment 1, the filtration target 11 is a biological substance contained in a liquid. In the present specification, the "biological substance" refers to a substance derived from a living organism such as a cell (eukaryote), a bacterium (prokaryote), a virus, and the like. As the cell (eukaryote), for example, there are included an ovum, a sperm, an induced pluripotent stem cell (iPS cell), an ES cell, a stem cell, a mesenchymal stem cell, a monocyte, a single cell, a cell aggregate, a planktonic cell, an adherent cell, a neural cell, a leukocyte, a lymphocyte, a cell for regenerative medicine, an autologous cell, a cancer cell, a blood circulating cancer cell (CTC), HL-60, HELA, and a fungus. As the bacterium (prokaryote), for example, there are included Escherichia coli and Mycobacterium tuberculosis.

[0065] The tubular member 3 forms a circulation flow path for the liquid 12 to flow. The tubular member 3 is, for example, a pipe having a circular, elliptical, rectangular, or the like cross-sectional shape. As the material of the tubular member 3, for example, there are mentioned stainless steel, silicone, PVDF (Teflon: registered trademark), vinyl chloride, glass, and butadiene-free resin. A coating material can also be applied to the inner surface of the tubular member 3 so that the filtration target 11 is difficult to adhere.

[0066] Both end portions of the tubular member 3 are arranged in the liquid tank 2. That is, one end portion 3A and the other end portion 3B of the tubular member 3 are arranged in the liquid tank 2.

[0067] The circulation pump 4 is installed in the tubular member 3, which circulates the liquid 12 housed in the liquid tank 2 from the one end portion 3A to the other end portion 3B of the tubular member 3. By driving of the circulation pump 4, the liquid 12 housed in the liquid tank 2 flows from the one end portion 3A to the other end portion 3B of the tubular member 3, and returns to the liquid tank 2. By continuing the driving of the circulation pump 4, the liquid 12 returned to the liquid tank 2 flows from the one end portion 3A to the other end portion 3B of the tubular member 3, and returns to the liquid tank 2 again.

[0068] The filter 5 that filters the filtration target 11 is provided to the side wall of the tubular member 3. As shown in FIG. 1, the filter 5 is installed in the through-hole 3a provided to a portion of the side wall of the tubular member 3 along the side wall. Figure 2

[0069] The filter 5 has a metal-made porous membrane 51 that filters the filtration target 11, and a frame 52 that holds the outer periphery of the metal-made porous membrane 51.

[0070] The metal-made porous membrane 51 is arranged along the flow direction of the liquid 12. In the present embodiment 1, the metal-made porous membrane 51 is a porous membrane for separating a biological substance. As shown in FIG. 2, the metal-made porous membrane 51 is installed in the through-hole 3a provided to a portion of the side wall of the tubular member 3 along the side wall. Figure 3 ​As shown, the metal-made porous membrane 51 has a first main surface 51a and a second main surface 51b facing each other. In addition, the metal-made porous membrane 51 is provided with a plurality of through-holes 51c that penetrate the first main surface 51a and the second main surface 51b. The through-holes 51c separate the biological substance from the liquid 12. The shape and size of the through-holes 51c are appropriately set according to the shape and size of the biological substance. The through-holes 51c are, for example, arranged at equal intervals or periodically. The shape of the through-holes 51c is, for example, a square when viewed from the first main surface 51a or the second main surface 51b of the metal-made porous membrane 51. The size of the through-holes 51c is, for example, 0.1 μm or more and 500 μm or less in the longitudinal direction, and 0.1 μm or more and 500 μm or less in the lateral direction. The interval between the through-holes 51c is, for example, greater than 1 times and 10 times or less, and more preferably 3 times or less, of the opening diameter of the through-holes 51c. In addition, the opening ratio of the through-holes 51c in the metal-made porous membrane 51 is, for example, 10% or more.

[0071] As the material of the metal-made porous membrane 51, for example, gold, silver, copper, platinum, nickel, stainless steel, palladium, titanium, cobalt, alloys thereof, and oxides thereof are cited. The size of the metal-made porous membrane 51 is, for example, 6 mm in diameter, and 0.1 μm or more and 100 μm or less, and preferably 0.1 μm or more and 50 μm or less, in thickness. The outer shape of the metal-made porous membrane 51 is, for example, any one of a circular shape, an elliptical shape, or a polygonal shape. In the present embodiment 1, the outer shape of the metal-made porous membrane 51 is a circular shape. In the outer peripheral portion of the metal-made porous membrane 51, the through-holes 51c can be provided or not provided.

[0072] The frame 52 includes a first frame 52a and a second frame 52b. The first frame 52a and the second frame 52b are each formed in a ring shape (for example, a circular ring shape). The frame 52 holds the metal-made porous membrane 51 by sandwiching the outer peripheral portion of the metal-made porous membrane 51 with the first frame 52a and the second frame 52b. As the material of the first frame 52a and the second frame 52b, for example, metals such as hard aluminum and aluminum, resins such as polyethylene, polystyrene, polypropylene, polycarbonate, polyacetal, and polyetherimide are cited.

[0073] As shown in FIG. 1, the filter 5 includes a metal-made porous membrane 51, a frame 52, and a filter housing 53. The filter 5 is configured to separate a biological substance from the liquid 12. Figure 2 As shown in FIG. 1, one end portion 6A of a filtrate discharge tube 6 is connected to the second frame 52b. The filtrate discharge tube 6 forms a filtrate flow path that allows the filtrate (waste liquid) that has passed through the filter 5 to flow. Figure 1 As shown in FIG. 1, the other end portion 6B of the filtrate discharge tube 6 is arranged in a filtrate tank 7. The filtrate that has flowed from the one end portion 6A to the other end portion 6B of the filtrate discharge tube 6 is stored in the filtrate tank 7. Figure 1 As shown in FIG. 1, the filtrate tank 7 can be an open-top container or a closed container.

[0074] In addition, as shown in FIG. 1, the filter 5 is provided with a liquid inlet tube 4 that is connected to the first frame 52a. The liquid inlet tube 4 forms a liquid flow path that allows the liquid 12 to flow into the filter 5. Figure 1As shown, a first bypass pipe 81 and a second bypass pipe 82 that short-circuit the circulation flow path are connected to the side wall of the tubular member 3. Both end portions of each of the first bypass pipe 81 and the second bypass pipe 82 are connected to the tubular member 3. The second bypass pipe 82 is connected so as to short-circuit the circulation flow path more than the first bypass pipe 81.

[0075] In the present embodiment 1, the first bypass pipe 81 and the second bypass pipe 82 are disposed at a position on the downstream side of the flow direction of the liquid 12 than the circulation pump 4 and at a position on the upstream side of the flow direction of the liquid 12 than the filter 5. The first bypass pipe 81 and the second bypass pipe 82 are pipes made of the same cross-sectional shape and material as the tubular member 3.

[0076] A first valve 91 is provided at a connection portion of the tubular member 3 and one end portion 81A of the first bypass pipe 81. A second valve 92 is provided at a connection portion of the tubular member 3 and the other end portion 81B of the first bypass pipe 81. In the present embodiment 1, a switching valve is constituted by the first valve 91 and the second valve 92, and the switching valve is switched so that the liquid 12 flowing in the tubular member 3 flows in the first bypass pipe 81.

[0077] A third valve 93 is provided at a connection portion of the tubular member 3 and one end portion 82A of the second bypass pipe 82. A fourth valve 94 is provided at a connection portion of the tubular member 3 and the other end portion 82B of the second bypass pipe 82. In the present embodiment 1, a switching valve is constituted by the third valve 93 and the fourth valve 94, and the switching valve is switched so that the liquid 12 flowing in the tubular member 3 flows in the second bypass pipe 82.

[0078] The circulation pump 4, the first valve 91, the second valve 92, the third valve 93, and the fourth valve 94 are electrically connected to the control section CT by wireless or wired. The control section CT controls the driving of the circulation pump 4, the switching operation of the first valve 91, the second valve 92, the third valve 93, and the fourth valve 94.

[0079] Next, the operation of the concentration device 1 to filter the filtration target 11 to obtain the concentrated liquid will be described with reference to Figures 4-7 , which is a flowchart showing the operation of the concentration device 1 to filter the filtration target 11 to obtain the concentrated liquid. Figure 4 , which is a flowchart showing the operation of the concentration device 1 to filter the filtration target 11 to obtain the concentrated liquid. Figures 5-7 , which is a flowchart showing the operation of the concentration device 1 to filter the filtration target 11 to obtain the concentrated liquid.

[0080] According to the operation such as the user pressing a start button (not shown), the control section CT drives the circulation pump 4 (step S1). As a result, as shown in Figure 5 , the liquid 12 in the liquid tank 2 flows from one end portion 3A to the other end portion 3B of the tubular member 3. At this time, the entire length from the one end portion 3A to the other end portion 3B of the tubular member 3 becomes the circulation flow path.

[0081] A portion of the liquid 12 flowing in the tubular member 3 passes through the filter 5, is collected in the filtrate tank 7 as filtrate through the filtrate discharge pipe 6. The filtration target 11 contained in the liquid 12 is filtered by the filter 5 to remain in the tubular member 3, flows to the other end portion 3B of the tubular member 3 in accordance with the flow of the liquid 12, and is collected in the liquid tank 2. Thus, in the liquid tank 2, the concentration of the filtration target 11 contained in the liquid 12 becomes high.

[0082] Next, when the remaining amount of the liquid 12 in the liquid tank 2 (concentrate) is equal to or less than the first threshold amount, as shown in FIG. 2, the control section CT switches the first valve 91 and the second valve 92 so that the liquid 12 flowing from the one end portion 3A of the tubular member 3 flows to the other end portion 3B of the tubular member 3 through the first bypass pipe 81 (steps S2, S3). Thus, the circulation flow path is short-circuited by the first bypass pipe 81. Note that, for example, the remaining amount of the liquid 12 in the liquid tank 2 can be measured by installing a water level gauge (not shown) in the liquid tank 2. Figure 6 A portion of the liquid 12 flowing in the circulation flow path short-circuited by the first bypass pipe 81 passes through the filter 5, is collected in the filtrate tank 7 as filtrate through the filtrate discharge pipe 6. The filtration target 11 contained in the liquid 12 is filtered by the filter 5 to remain in the tubular member 3, flows to the other end portion 3B of the tubular member 3 in accordance with the flow of the liquid 12, and is collected in the liquid tank 2. Thus, in the liquid tank 2, the concentration of the filtration target 11 contained in the liquid 12 becomes even higher.

[0083] Next, when the remaining amount of the liquid 12 in the liquid tank 2 is equal to or less than the second threshold amount, as shown in FIG. 3, the control section CT switches the third valve 93 and the fourth valve 94 so that the liquid 12 flowing from the one end portion 3A of the tubular member 3 flows to the other end portion 3B of the tubular member 3 through the second bypass pipe 82 (steps S4, S5). Thus, the circulation flow path is further short-circuited by the second bypass pipe 82.

[0084] Figure 7 A portion of the liquid 12 flowing in the circulation flow path further short-circuited by the second bypass pipe 82 passes through the filter 5, is collected in the filtrate tank 7 as filtrate through the filtrate discharge pipe 6. The filtration target 11 contained in the liquid 12 is filtered by the filter 5 to remain in the tubular member 3, flows to the other end portion 3B of the tubular member 3 in accordance with the flow of the liquid 12, and is collected in the liquid tank 2. Thus, in the liquid tank 2, the concentration of the filtration target 11 contained in the liquid 12 becomes still higher.

[0085] A portion of the liquid 12 flowing in the circulation flow path further short-circuited by the second bypass pipe 82 passes through the filter 5, is collected in the filtrate tank 7 as filtrate through the filtrate discharge pipe 6. The filtration target 11 contained in the liquid 12 is filtered by the filter 5 to remain in the tubular member 3, flows to the other end portion 3B of the tubular member 3 in accordance with the flow of the liquid 12, and is collected in the liquid tank 2. Thus, in the liquid tank 2, the concentration of the filtration target 11 contained in the liquid 12 becomes still higher.

[0086] ​Next, when the remaining amount of the liquid 12 in the liquid tank 2 is equal to or less than a third threshold amount, the control section CT stops the drive of the circulation pump 4 (steps S6, S7). In this way, a more concentrated concentrated liquid can be obtained in the liquid tank 2.

[0087] According to the concentration device 1 of the present embodiment 1, the first to fourth valves 91 to 94 are switched so that the liquid 12 flowing in the tubular member 3 flows in the first bypass pipe 81 or the second bypass pipe 82. According to this structure, in the initial stage of filtration, the inner volume of the circulation flow path can be increased, and a concentrated liquid can be obtained more quickly. In addition, by switching the first to fourth valves 91 to 94, the circulation flow path can be short-circuited, and the inner volume of the circulation flow path can be reduced. Thus, filtration can be continued while suppressing the generation of foam, and a more concentrated concentrated liquid can be obtained.

[0088] Note that, in the case where the filtration target 11 is a cell, the liquid 12 containing the cell is likely to be subjected to a shear force during the period in which it flows in the circulation flow path having a small diameter. Therefore, in the case where the concentration device is configured so that the cell flows only in the circulation flow path, the pressure caused by the shear force to which the cell is subjected becomes large.

[0089] In this regard, in the concentration device 1 of the present embodiment 1, since the concentration of the liquid 12 housed in the liquid tank 2 is targeted, the entire circulation flow path configured by switching the first to fourth valves 91 to 94 is configured to pass through the liquid tank 2. According to this structure, the liquid 12 containing the cell must flow to the circulation flow path via the liquid tank 2, and thus, in the liquid tank 2, the pressure caused by the shear force to which the cell is subjected can be temporarily alleviated. Thus, it is possible to suppress the occurrence of an adverse effect in which the cell proliferation does not progress when the cell is subcultured.

[0090] Note that the present application is not limited to the described embodiments, and can be implemented in various other ways. For example, in the described embodiments, the control section CT is controlled so that the first to fourth valves 91 to 94 are switched when the remaining amount of the liquid 12 housed in the liquid tank 2 is equal to or less than the first threshold amount or the second threshold amount, but the present application is not limited thereto. For example, in the case where foam is generated, the pressure or flow rate of the liquid 12 flowing in the tubular member 3 sharply decreases. That is, the timing at which foam is generated can be estimated based on the pressure or flow rate of the liquid 12 flowing in the tubular member 3. Therefore, the control section CT can also be controlled so that the first to fourth valves 91 to 94 are switched when the pressure or flow rate of the liquid 12 flowing in the tubular member 3 is equal to or less than a threshold value. According to this structure, it is also possible to suppress the generation of foam, and a more concentrated concentrated liquid can be obtained more quickly. Note that, for example, the pressure or flow rate of the liquid 12 flowing in the tubular member 3 can be measured by installing a pressure gauge or a flow rate gauge in the tubular member 3.

[0091] Further, the remaining amount of the liquid 12 accommodated in the liquid tank 2 has a correlation with the amount of the filtrate in the filtrate tank 7. Therefore, the control section CT can also be controlled to switch the first to fourth valves 91 to 94 when the amount of the filtrate in the filtrate tank 7 is equal to or more than a threshold value. According to this structure, it is also possible to suppress the generation of foam and to obtain a more concentrated concentrate liquid more quickly.

[0092] Further, the remaining amount of the liquid 12 accommodated in the liquid tank 2 has a correlation with the output and the driving time of the circulating pump 4. Therefore, the control section CT can also be controlled to switch the first to fourth valves 91 to 94 based on the output and the driving time of the circulating pump 4. According to this structure, it is also possible to suppress the generation of foam and to obtain a more concentrated concentrate liquid more quickly.

[0093] Further, in the above-described embodiment, the filter 5 is disposed at a position on the downstream side of the first and second bypass pipes 81 and 82 in the flow direction of the liquid 12, but the present application is not limited to this. For example, the filter 5 can also be disposed at a position on the upstream side of the first and second bypass pipes 81 and 82 in the flow direction of the liquid 12.

[0094] Further, in the above-described embodiment, the filtration is started in a state in which the first and second bypass pipes 81 and 82 are blocked by the first to fourth valves 91 to 94, but the present application is not limited to this. For example, the filtration can also be started in a state in which the first and second bypass pipes 81 and 82 are open (for example, in a state shown in FIG. 6). Figure 5 Figure 1 Further, in the above-described embodiment, the filtration is started in a state in which the first and second bypass pipes 81 and 82 are blocked by the first to fourth valves 91 to 94, but the present application is not limited to this. For example, the filtration can also be started in a state in which the first and second bypass pipes 81 and 82 are open (for example, in a state shown in FIG. 6).

[0095] Further, in the above-described embodiment, two bypass pipes (the first and second bypass pipes 81 and 82) are connected to the tubular member 3, but the present application is not limited to this. For example, one or more than three bypass pipes can also be connected to the tubular member 3. That is, at least one bypass pipe can be connected to the tubular member 3.

[0096] Further, in the above-described embodiment, four valves (the first to fourth valves 91 to 94) are provided as the switching valve, but the present application is not limited to this. The switching valve can be configured to switch so that the liquid 12 flowing in the tubular member 3 flows in the bypass pipe.

[0097] (Embodiment 2)

[0098] Figure 8 is a schematic configuration view of a concentration device 1A according to Embodiment 2 of the present application.

[0099] ​The concentration device 1A of this embodiment 2 differs from the concentration device 1 of the above-described embodiment 1 in that the filtrate pump 6P is provided in the filtrate discharge pipe 6.

[0100] The filtrate pump 6P is a pump that promotes passage of a portion of the liquid 12 flowing in the tubular member 3 through the filter 5. The filtrate pump 6P is electrically connected to the control section CT by wireless or wired.

[0101] As the filtration progresses, the filtrate 13 is removed from the liquid 12, the concentration of the filtration target in the liquid 12 flowing in the circulation flow path becomes higher, and the filtration target is likely to collide with other filtration targets or the side wall of the tubular member 3 and be pressed.

[0102] Therefore, the control section CT controls so that the filtrate pump 6P is driven at a first driving force smaller than before switching when the first valve 91 and the second valve 92 are switched so that the liquid flowing in the tubular member 3 flows in the first bypass pipe 81. In addition, the control section CT controls so that the filtrate pump 6P is driven at a second driving force smaller than the first driving force when the third valve 93 and the fourth valve 94 are switched so that the liquid flowing in the tubular member 3 flows in the second bypass pipe 82.

[0103] According to the concentration device 1A of this embodiment 2, it is possible to gradually (stagedly) slow down the filtration speed (concentration speed), to obtain a more concentrated concentrate more quickly, and to suppress the filtration target 11 from being pressed.

[0104] Note that the control section CT can also be controlled to switch the first valve 91 to the fourth valve 94 so that the liquid 12 flows in the second bypass pipe 82 for a longer time than the liquid 12 flows in the first bypass pipe 81. According to this structure, it is possible to slow down the speed of the concentrate flowing in the second bypass pipe 82, which is higher in concentration than the concentrate flowing in the first bypass pipe 81, and to further suppress the filtration target from being pressed.

[0105] (Embodiment 3)

[0106] Figure 9 is a schematic configuration view of the concentration device 1B of the embodiment 3 of the present application.

[0107] The concentration device 1B of this embodiment 3 differs from the concentration device 1 of the above-described embodiment 1 in that the bypass pipe filters 5A are provided in the first bypass pipe 81 and the second bypass pipe 82, respectively.

[0108] In this embodiment 3, the bypass pipe filter 5A has the same structure as the above-described filter. That is, the bypass pipe filter 5A has Figure 2The metal-made porous membrane 51 is shown. The filtrate that has passed through the bypass-pipe filter 5A is collected in the filtrate tank 7 through the filtrate discharge pipe 6.

[0109] According to the concentration device 1B of the present embodiment 3, even if the filter 5 is clogged, the filtration is continued through the bypass-pipe filter 5A, and thus a more highly concentrated concentrate can be obtained more quickly.

[0110] Note that, in the present embodiment 1, the first to fourth valves 91 to 94 are switched at the timing at which the foam is generated, but in the present embodiment 3, the first to fourth valves 91 to 94 can be switched at the timing at which the filter 5 is clogged. Thereby, it is possible to suppress the continuous filtration in the state in which the filter 5 is clogged. As a result, it is possible to suppress the filtration target adhered to the filter 5 from being pressed by other filtration targets.

[0111] For example, in the case where the filter 5 is clogged, the pressure of the filtrate 13 flowing in the filtrate discharge pipe 6 decreases. That is, it is possible to estimate the timing at which the filter 5 is clogged on the basis of the pressure of the filtrate 13 flowing in the filtrate discharge pipe 6. Therefore, for example, a pressure gauge (not shown) can be installed to the filtrate discharge pipe 6, and the control section CT can be controlled to switch the first to fourth valves 91 to 94 on the basis of the detected pressure of the pressure gauge.

[0112] In addition, for example, a CCD camera (not shown) can be installed at a position opposed to the filter 5, and the control section CT can be controlled to determine the clogging of the filter 5 on the basis of the image of the CCD camera, and switch the first to fourth valves 91 to 94.

[0113] (Embodiment 4)

[0114] Figure 10 is a schematic configuration view of the concentration device 1C of the present embodiment 4.

[0115] The concentration device 1C of the present embodiment 4 is different from the concentration device 1B of the present embodiment 3 in that the filter 5 is provided to a portion of the tubular member 3 provided in parallel to the first bypass pipe 81.

[0116] In the present embodiment 4, the control section CT is controlled to switch the first valve 91 and the second valve 92 so that the liquid 12 flows in the first bypass pipe 81 when the filter 5 provided to the tubular member 3 is clogged. In addition, the control section CT is controlled to switch the third valve 93 and the fourth valve 94 so that the liquid 12 flows in the second bypass pipe 82 when the bypass-pipe filter 5A provided to the first bypass pipe 81 is clogged.

[0117] According to the concentration device 1C of this Embodiment 4, even if the filter 5 is clogged, filtration is continued by the bypass pipe filter 5A, so a more highly concentrated concentrate can be obtained more quickly.

[0118] (Embodiment 5)

[0119] Figure 11 is a schematic configuration view of the concentration device 1D of Embodiment 5 of the present application.

[0120] The concentration device 1D of this Embodiment 5 differs from the concentration device 1 of Embodiment 1 in that the inner diameter (opening area) of the first bypass pipe 81 is smaller than the inner diameter of the tubular member 3, and the inner diameter of the second bypass pipe 82 is smaller than the inner diameter of the first bypass pipe 81.

[0121] According to the concentration device 1D of this Embodiment 5, the inner volume of the circulation flow path can be further reduced, and a more highly concentrated concentrate can be obtained. In addition, the filtration rate can be slowed down compared to the initial stage, and the pressure on the filtration target can be suppressed.

[0122] Note that in this case, at a position on the upstream side of the first bypass pipe 81 and the second bypass pipe 82 in the flow direction of the liquid 12, the flow of the liquid 12 is hindered when the liquid 12 flows from the tubular member 3 having a large inner diameter to the first bypass pipe 81 or the second bypass pipe 82 having a small inner diameter. As a result, the control of the pressure of the liquid 12 by the circulation pump 4 becomes difficult. Therefore, as shown in Figure 11 , the filter 5 is preferably provided at a position on the downstream side of the first bypass pipe 81 and the second bypass pipe 82 in the flow direction of the liquid 12. According to this configuration, the liquid can be filtered (concentrated) more stably by the filter 5.

[0123] Note that the effects of each of the embodiments can be achieved by appropriately combining any of the embodiments.

[0124] (Embodiment)

[0125] A specific example of filtering a liquid 12 containing a filtration target 11 to obtain a concentrate using the concentration device 1A of Embodiment 2 shown in Figure 8

[0126] ​Here, the inner diameters of the tubular member 3 and the first bypass pipe 81 are 4.3 mm, respectively. The inner diameter of the second bypass pipe 82 is 1.6 mm. In addition, the length of the tubular member 3 is 207 cm. The length of the circulation flow path that is short-circuited by the first bypass pipe 81 is 172 cm. The length of the circulation flow path that is short-circuited by the second bypass pipe 82 is 149 cm. That is, the inner volume of the circulation flow path based on the length of the tubular member 3 is about 30 ml. The inner volume of the circulation flow path that is short-circuited by the first bypass pipe 81 is about 25 ml. The inner volume of the circulation flow path that is short-circuited by the second bypass pipe 82 is 3 ml.

[0127] First, 500 ml of a cell suspension containing 5 x 10 6 cells is housed in the liquid tank 2 as the liquid 12 containing the filtration target 11.

[0128] Next, the circulation pump 4 and the filtrate pump 6P are driven, and the cell suspension is circulated in the circulation flow path based on the length of the tubular member 3 (refer to Figure 5 ). At this time, the discharge amount of the circulation pump 4 is 200 ml / min, and the discharge amount of the filtrate pump 6P is 20 ml / min.

[0129] Next, when the cell suspension in the liquid tank 2 is reduced from 500 ml to 100 ml, the first valve 91 and the second valve 92 are switched, and the cell suspension is circulated in the circulation flow path that is short-circuited by the first bypass pipe 81 (refer to Figure 6 ). At this time, the discharge amount of the circulation pump 4 is 200 ml / min, and the discharge amount of the filtrate pump 6P is 10 ml / min. The time required from the start of filtration to the switching of the first valve 91 and the second valve 92 is about 20 minutes.

[0130] Next, when the cell suspension in the liquid tank 2 is reduced from 100 ml to 50 ml, the third valve 93 and the fourth valve 94 are switched, and the cell suspension is circulated in the circulation flow path that is short-circuited by the second bypass pipe 82 (refer to Figure 7 ). At this time, the discharge amount of the circulation pump 4 is 200 ml / min, and the discharge amount of the filtrate pump 6P is 10 ml / min. The time required from the switching of the first valve 91 and the second valve 92 to the switching of the third valve 93 and the fourth valve 94 is about 5 minutes.

[0131] Next, when the cell suspension in the liquid tank 2 is reduced from 50 ml to 10 ml, the driving of the circulation pump 4 and the filtrate pump 6P is stopped. The time required from the switching of the third valve 93 and the fourth valve 94 to the stopping of the driving of the circulation pump 4 and the filtrate pump 6P is about 8 minutes. That is, the time during which the cell suspension flows in the second bypass pipe 82 is longer than the time during which the cell suspension flows in the first bypass pipe 81.

[0132] Therefore, in the present embodiment, 500 ml of a cell suspension containing 5 x 10 6The time required to concentrate the cell suspension containing 5 x 107cells from 500 ml to 10 ml was 33 minutes (= 20 minutes + 5 minutes + 8 minutes). Note that the cell suspension was circulated in the circulation flow path (refer to Fig. 2) that bypassed the filter 5 through the bypass pipe 82 from the time point at which the filtration was started, and the cell suspension was concentrated to 10 ml in 100 minutes or more. Figure 7 6 The time required to concentrate the cell suspension containing 5 x 107cells from 500 ml to 10 ml was 33 minutes (= 20 minutes + 5 minutes + 8 minutes). Note that the cell suspension was circulated in the circulation flow path (refer to Fig. 2) that bypassed the filter 5 through the bypass pipe 82 from the time point at which the filtration was started, and the cell suspension was concentrated to 10 ml in 100 minutes or more.

[0133] While the present application has been fully described in connection with the preferred embodiments with reference to the accompanying drawings, it is to be noted that various changes, modifications and alterations can be made therein by persons skilled in the art having the benefit of the present disclosure, such that such changes, modifications and alterations are to be understood as being included in the present application as set forth in the appended claims.

[0134] Industrial Applicability

[0135] The present application can obtain a concentrated solution having a higher concentration in a shorter time, and is therefore useful particularly in a concentration device that concentrates a liquid containing biological substances such as cells.

[0136] Explanation of Reference Numerals:

[0137] 1, 1A, IB, 1C, ID concentration device;

[0138] 2 liquid tank;

[0139] 3 tubular member;

[0140] 3a through hole;

[0141] 3A one end portion;

[0142] 3B other end portion;

[0143] 4 circulation pump;

[0144] 5 filter;

[0145] 5A filter for bypass pipe;

[0146] 6 filtrate discharge pipe;

[0147] 6A one end portion;

[0148] 6B other end portion;

[0149] 7 filtrate tank;

[0150] 11 filtration target;

[0151] 12 liquid;

[0152] 13 filtrate;

[0153] ​51 porous film made of metal;

[0154] 51a first main surface;

[0155] 51b second main surface;

[0156] 51c through-hole;

[0157] 52 frame;

[0158] 52a first frame

[0159] 52b second frame;

[0160] 81 first bypass pipe;

[0161] 81A one end portion;

[0162] 81B other end portion;

[0163] 82 second bypass pipe;

[0164] 82A one end portion;

[0165] 82B other end portion;

[0166] 91 first valve;

[0167] 92 second valve;

[0168] 93 third valve;

[0169] 94 fourth valve;

[0170] CT control unit.

Claims

1. A concentration device that is a cross-flow type concentration device that concentrates a liquid containing a filtration target object, the concentration device comprising: a liquid tank that stores the liquid; a tubular member whose both end portions are disposed in the liquid tank and forms a circulation flow path; a circulation pump that circulates the liquid stored in the liquid tank from one end portion to the other end portion of the tubular member; a filter that is provided to a side wall of the tubular member and has a metal-made porous membrane that filters the filtration target object; a filtrate discharge pipe that forms a filtrate flow path in which a filtrate that has passed through the filter flows; a bypass pipe that connects both end portions thereof to the side wall of the tubular member and short-circuits the circulation flow path to substantially reduce the inner volume of the circulation flow path; a switching valve that switches so that the liquid flowing in the tubular member flows in the bypass pipe; and a control unit that controls the driving of the circulation pump and the switching operation of the switching valve, the filter is disposed at a position that is on a downstream side of the bypass pipe in a flow direction of the liquid, the concentration device further comprises a bypass pipe filter that is provided to a side wall of the bypass pipe and has a metal-made porous membrane that filters the filtration target object.

2. The concentration device according to claim 1, wherein when the remaining amount of the liquid stored in the liquid tank is equal to or less than a threshold amount, the control unit switches the switching valve so that the liquid flowing in the tubular member flows in the bypass pipe.

3. The concentration device according to claim 1, wherein when the pressure or flow rate of the liquid flowing in the tubular member is equal to or less than a threshold value, the control unit switches the switching valve so that the liquid flowing in the tubular member flows in the bypass pipe.

4. The concentration device according to any one of claims 1 to 3, wherein the concentration device further comprises a filtrate pump that causes a part of the liquid flowing in the tubular member to pass through the filter, the control unit reduces the driving force of the filtrate pump when the switching valve is switched so that the liquid flowing in the tubular member flows in the bypass pipe.

5. The concentration device according to claim 4, wherein the bypass pipe comprises a first bypass pipe and a second bypass pipe that short-circuits the circulation flow path more than the first bypass pipe, the switching valve is configured to switch so that the liquid flowing in the tubular member flows in the first bypass pipe or the second bypass pipe, the control unit drives the filtrate pump at a first driving force when the switching valve is switched so that the liquid flowing in the tubular member flows in the first bypass pipe, drives the filtrate pump at a second driving force that is smaller than the first driving force when the switching valve is switched so that the liquid flowing in the tubular member flows in the second bypass pipe.

6. The concentration device according to claim 4, wherein the bypass pipe comprises a first bypass pipe and a second bypass pipe that short-circuits the circulation flow path more than the first bypass pipe, the switching valve is configured to switch so that the liquid flowing in the tubular member flows in the first bypass pipe or the second bypass pipe, The switching valve is configured to switch so that the liquid flowing in the tubular member flows in the first bypass pipe or the second bypass pipe, The control section switches the switching valve so that the liquid flows in the second bypass pipe for a longer time than the liquid flows in the first bypass pipe.

7. The concentration device according to any one of claims 1 to 3, wherein The inner diameter of the bypass pipe is smaller than the inner diameter of the tubular member.

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