Filtration device and filtration method

Abstract

The present invention addresses the problem of providing a filtration device and a filtration method for continuously filtering a sample by means of a continuously conveyed filter media sheet, wherein air contamination of the filtrate can be prevented or reduced. The filtration device comprises: a sample supply unit; a filter media sheet support member provided below the sample supply unit; a suction unit that suctions the fluid sample filtered through the filter media sheet supported by the filter media sheet support member, the fluid sample being suctioned from the opposite side of the filter media sheet relative to the sample supply unit; and a conveyance mechanism that continuously supplies the filter media sheet to the filter media sheet support member. The problem is solved by the filtration device comprising one or more of the following air contamination prevention mechanisms (1) to (3): (1) an angle adjustment member for adjusting the angle at which the filter media sheet is supplied to a support surface of the filter media sheet support member; (2) a position adjustment member for adjusting the relative position of the sample supply unit and the suction unit in the filter media sheet conveyance direction; and (3) a moistening member for moistening the filter media sheet before the filter media sheet is supplied to the filter media sheet support member.

Description

Filtration device and filtration method

[0001] The present invention relates to a filtering device and a filtering method.

[0002] In quantitative analysis, the separation of the target substance from other inhibitors is very important for accurate analysis. There are various separation methods such as solvent extraction, solid-phase extraction, chelate extraction, and chromatographic separation, but filtration is frequently used as a physical method for separating suspended matter from solution.

[0003] In qualitative and quantitative analysis, filtration is used to separate suspended matter from the solution when supplying samples to an analytical instrument. Filtration is usually performed for each sample, and the filtered sample is then fed to the analytical instrument.

[0004] As an example of an apparatus for continuously filtering samples to be continuously analyzed, Patent Document 1 discloses a filtering device that includes a sample supply section, a filter sheet that is continuously transported below the sample supply section, and a suction section that sucks the filtered fluid sample from the opposite side of the filter sheet from the sample supply section.

[0005] Japanese Patent Publication No. 2022-177660

[0006] In the conventional techniques described above, the sample supply flow rate is set to be higher than the sample suction flow rate to prevent air from being mixed into the filtrate, but air occasionally gets mixed into the filtrate, which can reduce filtration efficiency and adversely affect analytical results.

[0007] One embodiment of the present invention aims to provide a filtration device and a filtration method that continuously filters a sample using a continuously transported filter sheet, and that can prevent or reduce the inclusion of air in the filtrate.

[0008] In order to solve the above problems, a filtration device according to one embodiment of the present invention includes the following configuration.

[0009] 1. A filtration device for filtering a fluid sample, comprising: a sample supply unit; a filter sheet support member provided below the sample supply unit; a suction unit that suctions the filtered fluid sample from a filter sheet supported by the filter sheet support member from the opposite side to the sample supply unit; and a transport mechanism that continuously supplies the filter sheet to the filter sheet support member, wherein the support member is a base having a support surface for the filter sheet, and the base is provided with a through-hole for suctioning the fluid sample that has passed through the filter sheet by the suction unit, and the filter sheet support member is arranged at a position where the filter sheet supported by the filter sheet support member does not come into contact with the sample supply unit, and the filtration device comprises one or more of the following air intrusion prevention mechanisms (1) to (3): (1) an angle adjustment member that adjusts the angle at which the filter sheet is supplied to the support surface of the filter sheet support member; (2) a position adjustment member that adjusts the relative position of the sample supply unit and the suction unit in the filter sheet transport direction; (3) A wetting member that wets the filter sheet before the filter sheet is fed to the filter sheet support member.

[0010] In order to solve the above problems, a filtration method according to one embodiment of the present invention includes the following configuration.

[0011] A filtration method for filtering a fluid sample, comprising: a step of supplying the fluid sample from a sample supply unit; and a filtration step of filtering the supplied fluid sample with a filter sheet provided below the sample supply unit, wherein in the filtration step, the filtered fluid sample is sucked by a suction unit from the opposite side of the filter sheet from the sample supply unit, the sample supply unit and the filter sheet are not in contact with each other, and the filter sheet is continuously transported below the sample supply unit; and the filtration method comprises one or more of the following air inclusion prevention steps (1) to (3): (1) an angle adjustment step of adjusting the angle at which the filter sheet is supplied below the sample supply unit; (2) a position adjustment step of adjusting the relative position of the sample supply unit and the suction unit in the filter sheet transport direction; and (3) a wetting step of wetting the filter sheet before it is supplied below the sample supply unit.

[0012] According to one embodiment of the present invention, a filtration device and a filtration method can be provided that can prevent or reduce the inclusion of air in the filtrate, thereby preventing a decrease in filtration efficiency and adverse effects on analytical results.

[0013] FIG. 1 is a side view showing a schematic configuration of a filtration device according to one embodiment of the present invention. FIG. 2 is a perspective view showing a partial configuration of a filtration device according to one embodiment of the present invention. FIG. 3 is a perspective view showing a partial configuration of a filtration device according to one embodiment of the present invention. FIG. 4 is a side view showing a position adjustment member and a filter sheet support member in a filtration device according to one embodiment of the present invention. FIG. 5 is a diagram showing the relationship between the relative positions of a sample supply unit and a suction unit in the filter sheet conveying direction and the range through which a fluid sample flows in a filtration device according to one embodiment of the present invention. FIG. 6 is a side view showing a schematic configuration of a filtration device according to one embodiment of the present invention. FIG. 7 is a side view showing a schematic configuration of a filtration device according to one embodiment of the present invention. FIG. 8 is a side view showing a schematic configuration of a filtration device according to one embodiment of the present invention. FIG. 9 is a side view showing a schematic configuration of a filtration device according to one embodiment of the present invention. FIG. 10 is a perspective view showing a partial configuration of a filtration device according to one embodiment of the present invention. FIG. 11 is a diagram showing a schematic configuration of a flow analyzer according to one embodiment of the present invention. FIG. 12 is a diagram showing a schematic configuration of a flow analyzer according to one embodiment of the present invention.

[0014] Hereinafter, embodiments of the present invention will be described in detail. However, the present invention is not limited to these, and various modifications are possible within the scope of the description. Embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the present invention. In addition, unless otherwise specified in this specification, "A to B" representing a numerical range means "greater than or equal to A and less than or equal to B."

[0015] (I) Filtration Device (I-1) Embodiment 1 In the process of investigating the cause of air being mixed into the filtrate, the inventors noticed that when the filter sheet is supplied to the base that supports the filter sheet, a pressure guide is applied from above to the filter sheet to align it with the support surface upstream of the base in the filter sheet conveyance direction, but the filter sheet does not adhere sufficiently to the support surface, resulting in a gap. Note that in this specification, "applying pressure to the filter sheet from above" means that the pressure guide itself does not move, but the filter sheet is pressed down by the pressure guide.

[0016] Therefore, the inventors arranged a pressure guide so that the lower part of the longitudinal side of the pressure guide was in contact with the surface extending upstream of the support surface in the filter sheet conveyance direction, so that the filter sheet was fed parallel to the support surface of the base. However, even with this method, the filter sheet could not be sufficiently adhered to the support surface. This was thought to be because when the pressure guide applied downward pressure to the filter sheet, the filter sheet rebounded upward and floated off the support surface. Furthermore, it was found that the smaller the angle between the upper surface of the filter sheet on the upstream side of the pressure guide in the filter sheet conveyance direction and the support surface, the greater the rebound of the filter sheet when downward pressure was applied.

[0017] Based on this knowledge, the inventors conducted extensive research to improve the adhesion of the filter sheet to the support surface, and found that by further providing a mechanism for adjusting the angle between the surface of the filter sheet on the upstream side of the pressure guide in the filter sheet conveying direction and the support surface, it is possible to prevent the filter sheet from floating off the support surface and prevent air from being mixed into the filtrate. In other words, it was found that by using an angle adjustment member equipped with the pressure guide and the mechanism to adjust the angle at which the filter sheet is supplied to the support surface of the filter sheet support member, it is possible to prevent the filter sheet from floating off the support surface and prevent air from being mixed into the filtrate.

[0018] That is, the filtration device of embodiment 1 is a filtration device for filtering a fluid sample, and comprises a sample supply section, a filter sheet support member provided below the sample supply section, an suction section that suctions the filtered fluid sample from the opposite side of the sample supply section to the filter sheet supported by the filter sheet support member, and a conveying mechanism that continuously supplies the filter sheet to the filter sheet support member, wherein the support member is a base having a support surface for the filter sheet, and the base is provided with a through hole for suctioning the fluid sample that has passed through the filter sheet by the suction section, and the filter sheet support member is positioned at a position where the filter sheet supported by the filter sheet support member does not come into contact with the sample supply section, and is equipped with an angle adjustment member that adjusts the angle at which the filter sheet is supplied to the support surface of the filter sheet support member.

[0019] The filtration device according to the first embodiment will be described below with reference to Figs. 6, 3, and 9. Fig. 6 is a side view showing a schematic configuration of the filtration device according to the first embodiment. Fig. 3 is a perspective view showing the configuration of a portion of the filtration device according to one embodiment of the present invention. Fig. 9 is a perspective view showing the configuration of an angle adjustment member of the filtration device according to one embodiment of the present invention. Note that hereinafter in this specification, the "filter material sheet conveying direction" may be simply referred to as the "conveying direction."

[0020] The filtration device 1a according to the first embodiment is a filtration device for filtering a fluid sample. The term "fluid sample" is not particularly limited as long as it is a fluid sample, but it may be, for example, a suspension sample containing soluble and insoluble components. The term "filtering" refers to separating and removing insoluble components having a certain particle size or larger from the fluid sample. As shown in FIG. 6, the filtration device 1a according to the first embodiment includes a sample supply unit 2, a suction unit 4, a filter sheet support member 3 (hereinafter sometimes simply referred to as the "support member"), and a winding device (not shown).

[0021] The sample supply unit 2 is a member for supplying a fluid sample to the filter sheet 7. The sample supply unit 2 is provided with a sample supply port for discharging the fluid sample.

[0022] The filter sheet support member 3 is provided below the sample supply unit 2. Specifically, the filter sheet support member 3 is located between the sample supply unit 2 and the suction unit 4, at a position where the filter sheet 7 supported by the filter sheet support member 3 can receive the fluid sample that is discharged from the sample supply port and drops down.

[0023] The support member 3 is a member for supporting the filter sheet 7. The support member 3 is a base having a support surface for the filter sheet 7. The base is formed with a through-hole 6 for aspirating the fluid sample that has passed through the filter sheet 7 by the aspirator 4.

[0024] The filter sheet 7 can be continuously transported by winding up the rolled filter sheet 8 using a winding device (not shown). Continuously transporting the filter sheet 7 ensures that new filter sheet 7 is always transported between the sample supply unit 2 and the suction unit 4. Therefore, excess fluid sample not sucked into the suction unit 4 is discharged along with the filtered filter sheet 7 (waste filter sheet) without diffusing upstream along the surface of the filter sheet 7 in the transport direction. Therefore, it is not necessary to install a new filter sheet for each fluid sample. In the filtration device shown in FIG. 6 , the filter sheet 7 can be continuously transported by being wound up by a winding device. However, as long as the filter sheet 7 can be transported, the mechanism does not necessarily have to rely on winding up by a winding device. For example, the filter sheet 7 may be transported by a belt conveyor.

[0025] The angle adjustment member 15 adjusts the angle at which the filter sheet 7 is supplied to the support surface of the filter sheet support member 3. The angle adjustment member 15 includes an arm 12, one end of which is attached with a pressure guide 13 that presses the filter sheet 7 downward, and the other end of which is attached with a guide roller 14, and an angle adjustment mechanism. The arm 12 is positioned so that the pressure guide 13 is located downstream in the conveyance direction relative to the guide roller 14. The pressure guide 13 is a rod-shaped member that does not rotate around its longitudinal center line as its axis of rotation. The arm 12 is a member that extends linearly with a predetermined length. As shown in Figures 6 and 3, the pressure guide 13 is fixed to the frame 5 so that the lower end of its longitudinal side is in contact with an extension line of the support surface of the support member 3 toward the upstream side in the conveyance direction. The arm 12 is rotatably fixed to the frame 5 at the location where the pressure guide 13 is attached, and is rotatable on a plane perpendicular to the filter sheet, with the location where the pressure guide 13 is attached as the center of its axis of rotation. According to this configuration, the pressure guide 13 can press the filter sheet 7 downward, along an extension of the support surface of the support member 3 toward the upstream side in the conveying direction. The position of the guide roller 14 can be adjusted by rotating the arm 12 in the direction indicated by arrow d in FIG. 3 , with the point where the pressure guide 13 is attached as the center of rotation. This increases the angle α between the upper surface of the filter sheet 7 on the upstream side of the pressure guide 13 in the filter sheet conveying direction and the support surface (see FIG. 6 for α). This allows the filter sheet 7 to be in close contact with the support surface of the support member 3 without floating. α is preferably 110 to 180 degrees, more preferably 145 to 155 degrees. In the above-described embodiment, the pressure guide 13 does not rotate around its longitudinal centerline as a rotation axis. However, a rod-shaped member that can rotate around its longitudinal centerline as a rotation axis may also be used as the pressure guide 13.

[0026] However, the lowest point where the guide roller 14 and the filter sheet 7 come into contact is located above the plane extending from the support surface.

[0027] The angle adjustment by the angle adjustment member 15 may be performed while the filtration device is in operation or when the operation of the filtration device is stopped. That is, while the filtration device is in operation or when it is stopped, the arm 12 is rotated by the angle adjustment mechanism around the point where the pressing guide 13 is attached as the center of the rotation axis, and the position of the guide roller 14 is adjusted to a position where the filter medium sheet 7 is in close contact with the support surface of the support member 3 without floating, and then the arm 12 is fixed so as not to rotate by a fixing mechanism (not shown), thereby fixing the guide roller 14 in the optimal position.

[0028] Figure 9 shows an example of a method for adjusting the angle using the angle adjustment member 15. In the example of Figure 9, an arm 12 with a guide roller 14 attached is attached to a pressure guide 13 fixed to the frame 5 by a fixture (fixing screw) 22, and the arm 12 is rotated around the point where the pressure guide 13 is attached, as the center of the rotation axis, to adjust the position of the guide roller 14. After adjusting the position so that the filter sheet 7 is in close contact with the support surface of the support member 3 without floating, the fixture (fixing screw) 21 is tightened to fix the arm 12 so that it does not rotate. In this example, the arm can be rotated by loosening the fixture (fixing screw) 21. Therefore, in this example, the fixture (fixing screw) 21 can also be considered an angle adjustment mechanism.

[0029] The longitudinal length of the pressing guide 13 and the longitudinal length of the guide roller 14 are not particularly limited as long as they can stably support the filter sheet 7, and may be the same as the width of the filter sheet 7, or may be larger or smaller than the width of the filter sheet 7. Furthermore, the longitudinal length of the pressing guide 13 and the longitudinal length of the guide roller 14 may be the same or different.

[0030] The conveying speed of the filter sheet 7 may be any speed that does not allow excess fluid sample that has not been sucked into the suction unit 4 to be diffused upstream in the conveying direction on the surface of the filter sheet 7. The conveying speed of the filter sheet 7 may be set appropriately depending on the supply flow rate of the fluid sample supplied from the sample supply unit 2 and the suction flow rate of the fluid sample that is sucked through the filter sheet 7. The conveying speed of the filter sheet 7 may be, for example, 0.5 cm / min to 10 cm / min, 1 cm / min to 7 cm / min, or 3 cm / min to 5 cm / min.

[0031] The filter sheet 7 and the support surface of the support member 3 are inclined from the upstream to the downstream in the transport direction. This allows excess fluid sample not sucked into the suction unit 4 to flow downstream in the transport direction, more effectively preventing it from flowing from downstream to upstream in the transport direction. As a result, the filter sheet 7 is continuously transported, and the portion of the filter sheet 7 not used for filtration can catch the fluid sample that is discharged from the sample supply port and falls. Excess fluid sample that does not soak into the filter sheet 7 is discharged below the support member 3 as waste liquid together with the waste filter sheet.

[0032] The inclination angle of the filter sheet 7 and the support surface of the support member 3 relative to the horizontal direction is not particularly limited, but is preferably 1 to 30 degrees, more preferably 5 to 20 degrees, and even more preferably 8 to 15 degrees. By setting the inclination angle of the filter sheet 7 and the support surface within this range, the filter sheet 7 can reliably receive the fluid sample discharged from the sample supply port and dropped, while more effectively preventing excess fluid sample not aspirated by the suction unit 4 from flowing from downstream to upstream in the transport direction. In the filtration device shown in FIGS. 6 and 3 , the support surfaces of the filter sheet 7 and the support member 3 are inclined from top to bottom from upstream to downstream in the transport direction. However, as long as excess fluid sample not aspirated by the suction unit 4 does not significantly diffuse across the surface of the filter sheet 7 toward the upstream side in the transport direction, the support surfaces of the filter sheet 7 and the support member 3 do not necessarily have to be inclined, and may be inclined from bottom to top from upstream to downstream in the transport direction.

[0033] The filter sheet 7 is preferably strip-shaped. The width of the filter sheet 7 may be large enough to adequately catch the fluid sample that has been discharged from the sample supply port and dropped. The width of the filter sheet 7 may be, for example, 5 mm to 100 mm, 10 mm to 40 mm, 15 mm to 35 mm, or 20 mm to 30 mm.

[0034] The filter sheet 7 may be any material capable of separating soluble and insoluble components contained in a fluid sample. Examples of filter sheets include filter paper sheets, cloth sheets, and membrane sheets. Examples of materials for the filter sheet 7 include cellulose, polytetrafluoroethylene (PTFE), glass fiber, polyethylene, polypropylene, polyester, rayon, pulp, cotton, hemp, and silk.

[0035] The suction unit 4 suctions the filtered fluid sample from the opposite side of the filter sheet 7 to the sample supply unit 2. A pump (not shown) is connected to the suction unit 4, and the suction unit 4 can suction the filtered fluid sample by using the pump.

[0036] The support member 3 is positioned so that the filter sheet 7 supported by the support member 3 does not come into contact with the sample supply unit 2. The fluid sample supplied from the sample supply unit 2 drops and is filtered by the filter sheet 7. This allows gases contained in the fluid sample (e.g., gases used for segmentation, air occasionally mixed in, gases generated during decomposition, etc.) to be released into the air.

[0037] The supply flow rate of the fluid sample supplied from the sample supply unit 2 is preferably set to be greater than the suction flow rate of the fluid sample that is sucked through the filter sheet 7. This makes it difficult for the suction unit 4 to take in gas when sucking the filtered fluid sample.

[0038] The supply flow rate of the fluid sample supplied from the sample supply unit 2 is preferably 1.05 to 3.0 times, and more preferably 1.1 to 2.0 times, the suction flow rate of the fluid sample aspirated through the filter sheet 7, for example. This allows the suction unit 4 to aspirate the filtered fluid sample while reducing gas intake, and reduces waste of the sample supplied to the filtration device. For example, when the supply flow rate of the fluid sample supplied from the sample supply unit 2 is 0.3 mL / min to 5.0 mL / min, the suction flow rate of the fluid sample aspirated through the filter sheet 7 is preferably 0.2 mL / min to 4.5 mL / min. Furthermore, when the supply flow rate of the fluid sample supplied from the sample supply unit 2 is 0.5 mL / min to 5.0 mL / min, the suction flow rate of the fluid sample aspirated through the filter sheet 7 is preferably 0.3 mL / min to 4.0 mL / min. Furthermore, when the supply flow rate of the fluid sample supplied from the sample supply unit 2 is 1 m / s ...2 mL / min to 4.5 mL / min. When the flow rate is 0 L / min to 3.0 mL / min, the suction flow rate of the fluid sample that is sucked through the filter sheet 7 is preferably 0.5 mL / min to 2.0 mL / min.

[0039] The width of the support member 3 is not particularly limited as long as it can stably support the filter sheet 7, and it may be the same as the width of the filter sheet 7, or it may be larger or smaller than the width of the filter sheet 7.

[0040] A tubular suction part 4 is inserted into the through-hole 6 so as to be in close contact with the through-hole 6. The inner diameter of the through-hole 6 may be large enough to allow the suction part 4 to be inserted and for all of the filtered fluid sample to be sucked into the inside of the suction part 4 without leakage. The inner diameter of the through-hole 6 may be, for example, 0.2 mm to 10.0 mm, 1.0 mm to 5.0 mm, or 2.0 mm to 4.0 mm.

[0041] The outer diameter of the suction part 4 need only be large enough to allow it to be inserted into the through-hole 6 and to allow all of the filtered fluid sample to be sucked into the inside of the suction part 4 without leakage. Therefore, it is preferable that the inner diameter of the through-hole 6 and the outer diameter of the suction part 4 are the same. The outer diameter of the suction part 4 may be, for example, 0.2 mm to 10.0 mm, 1.0 mm to 5.0 mm, or 2.0 mm to 4.0 mm.

[0042] The inner diameter of the suction part 4 may be any size that allows all of the filtered fluid sample to be aspirated into the suction part 4 and that allows stable filtration to be performed. The inner diameter of the suction part 4 may be, for example, 0.05 mm to 5.0 mm, 0.1 mm to 2.0 mm, or 0.2 mm to 1.5 mm.

[0043] Alternatively, instead of the suction part 4 being inserted into the through hole 6, the through hole 6 itself may be the suction part 4, and the through hole 6 may be connected to a pipeline to which a pump is connected.

[0044] (I-2) Embodiment 2 The inventors further focused on the fact that the range of the fluid sample flowing on the filter sheet changes depending on the relative positions of the sample supply unit and the suction unit in the filter sheet conveyance direction. Figure 5 shows the relationship between the relative positions of the sample supply unit and the suction unit in the filter sheet conveyance direction and the range of the fluid sample flow. Figure 5 is a top view of the support member 3, with the arrow indicating the filter sheet conveyance direction and the shaded area indicating the range of the fluid sample flow. Specifically, Figure 5 shows the range of the fluid sample flowing on the filter sheet (on the support member 3) when the sample supply unit 2 is positioned directly above the suction unit (through-hole 6 in the support member 3) (20) and when the sample supply unit 2 is positioned upstream of the suction unit (through-hole 6 in the support member 3) in the conveyance direction (30). As shown in Figure 5, when the sample supply unit 2 is positioned upstream of the suction unit in the conveyance direction, the area of ​​the fluid sample flowing through the suction unit is significantly increased compared to when the sample supply unit is positioned directly above the suction unit. Note that Figure 5 shows the relationship between the relative positions and the range through which the fluid sample flows when the filter sheet and the support surface of the support member 3 are inclined from top to bottom from upstream to downstream in the conveying direction, or when they are not inclined.

[0045] Based on this finding, the inventors hypothesized that an insufficient area of ​​the fluid sample flowing through the suction section was one cause of air mixing into the filtrate, and that increasing the area of ​​the fluid sample flowing through the suction section would reduce air mixing into the filtrate. Therefore, they provided the filtration device with a position adjustment member that adjusts the relative positions of the sample supply section and the suction section in the filter sheet conveyance direction, and positioned the sample supply section upstream of the suction section in the conveyance direction, and found that this indeed reduced air mixing into the filtrate.

[0046] That is, the filtration device of embodiment 2 is a filtration device for filtering a fluid sample, and comprises a sample supply section, a filter sheet support member provided below the sample supply section, a suction section that sucks the filtered fluid sample from the opposite side of the sample supply section to the filter sheet supported by the filter sheet support member, and a conveying mechanism that continuously supplies the filter sheet to the filter sheet support member, wherein the support member is a base having a support surface for the filter sheet, and the base is provided with a through hole for sucking the fluid sample that has passed through the filter sheet by the suction section, and the filter sheet support member is positioned at a position where the filter sheet supported by the filter sheet support member and the sample supply section do not come into contact, and is provided with a position adjustment member that adjusts the relative position of the sample supply section and the suction section in the filter sheet conveying direction.

[0047] A filtration device according to a second embodiment will be described below with reference to Fig. 7, Fig. 3, and Fig. 4. Fig. 7 is a side view showing a schematic configuration of a filtration device according to the second embodiment. Fig. 3 is a perspective view showing a configuration of a portion of a filtration device according to one embodiment of the present invention. Fig. 4 is a side view showing a position adjustment member and a filter sheet support member in the filtration device according to the second embodiment.

[0048] In the filtering device 1b according to the second embodiment, the sample supplying section 2, the suction section 4, the filter sheet supporting member 3, and the winding device are the same as those in the filtering device according to the first embodiment.

[0049] The position adjustment member 16 is a member that grips the sample supply unit 2 so as to be movable upstream and downstream along the conveyance direction of the filter sheet 7 (in this embodiment, if the conveyance direction of the filter sheet is inclined relative to the horizontal, this refers to the direction of the conveyance direction projected onto a horizontal plane, i.e., the direction indicated by the arrow (x) in Figure 4). As shown in Figures 3 and 4, the position adjustment member 16 has two guide holes 17 that guide the sample supply unit 2 along the conveyance direction as a conveyance direction position adjustment mechanism for adjusting the position of the sample supply unit 2 in the filter sheet conveyance direction, and is also equipped with a gripping mechanism 18 that grips the sample supply unit 2. The guide holes 17 are elongated holes extending in the filter sheet conveyance direction. Fixing devices (fixing screws) for fixing the position adjustment member 16 to the frame 5 are inserted into the guide holes 17, respectively. Loosening the fixing devices (fixing screws) allows the sample supply unit 2 to be moved along the conveyance direction. By moving the sample supply unit 2 along the transport direction, the relative positions of the sample supply unit and the suction unit in the filter sheet transport direction can be adjusted to a position that reduces the mixing of air into the filtrate, and then the sample supply unit 2 can be fixed in the optimal position by using a fixing device (fixing screw) to prevent it from moving.

[0050] In the filtering device shown in Figures 7, 3, and 4, two guide holes 17 are formed in the position adjustment member 16, but the number of guide holes 17 is not limited to two and may be one, or three or more. The fastener is not limited to a screw. Furthermore, the conveying direction position adjustment mechanism is not limited to a guide hole as long as it can adjust the position along the conveying direction.

[0051] On the support surface of the support member 3, the distance between the position where the fluid sample is supplied from the sample supply section 2 (the position where the fluid sample falls) and the position of the suction section (the through-hole 6 of the support member 3) is, for example, 0.5 mm to 10.0 mm, more preferably 1.0 mm to 5.0 mm, and even more preferably 2.0 mm to 4.0 mm.

[0052] In addition, in an embodiment that does not include a position adjustment member 16, the distance on the support surface of the support member 3 between the position where the fluid sample is supplied from the sample supply unit 2 (the position where the fluid sample falls) and the position of the suction unit 4 (the through-hole 6 of the support member 3) is, for example, greater than 0 mm and less than 0.5 mm.

[0053] 7, 3, and 4, the sample supply unit 2 is disposed upstream of the suction unit (through-hole 6 of the support member 3) in the conveying direction, but the sample supply unit 2 may be disposed downstream of the suction unit (through-hole 6 of the support member 3) in the conveying direction. For example, if the filter medium sheet and the support surface of the support member 3 are inclined from bottom to top from the upstream to the downstream in the conveying direction, the sample supply unit 2 may be disposed downstream of the suction unit (through-hole 6 of the support member 3) in the conveying direction.

[0054] In addition to the transport direction position adjustment mechanism, the position adjustment member 16 also includes a gripping mechanism 18 that grips the sample supply unit 2. In FIG. 3 , the gripping mechanism 18 is a gripping member 18 formed to protrude toward the sample supply unit 2 from the surface on which the guide hole 17 is formed. The gripping member 18 includes a pair of clamping plates that can move toward and away from each other in the horizontal direction. A groove with an arc-shaped cross section is formed in the vertical direction on each of the opposing surfaces of the pair of clamping plates, extending from the upper end to the lower end of the clamping plate. The tubular sample supply unit 2, through which the fluid sample flows, can be freely inserted into the space formed by the two grooves of the pair of clamping plates so that it can be raised and lowered in the vertical direction. A screw hole is formed at the tip of each of the pair of clamping plates, perpendicular to the surface of the clamping plate. After adjusting the vertical position of the sample supply unit 2, the sample supply unit 2 can be fixed to prevent movement with a fixing device (fixing screw), thereby adjusting the vertical position of the sample supply unit 2 (the direction indicated by the arrow (y) in FIG. 4 ). 3, the pair of clamping plates are formed integrally with the position adjustment member 16, but the pair of clamping plates may each be formed as a separate member. Also, the gripping mechanism 18 may be any mechanism as long as it is a member that can grip the sample supply part 2 and can be adjusted to be raised and lowered in the vertical direction.

[0055] The distance between the sample supply port of the sample supply unit 2 and the support surface of the filter sheet support member 3 is, for example, 0.1 mm to 10.0 mm, more preferably 0.5 mm to 5.0 mm, and even more preferably 1.0 mm to 3.0 mm. Here, the distance between the sample supply port of the sample supply unit 2 and the support surface of the filter sheet support member 3 refers to the length of a line drawn vertically downward from the sample supply port of the sample supply unit 2 to the support surface of the filter sheet support member 3. A distance of 0.1 mm or more is preferable because it prevents contamination and damage to the filter sheet caused by bringing the sample injection port close to the filter sheet. Furthermore, a distance of 10.0 mm or less is preferable because it prevents air from being mixed in before the fluid sample reaches the filter sheet after being dropped.

[0056] 3, the position adjustment member 16 (gripping mechanism 18) can adjust the sample supply unit 2 so that it can be raised and lowered in the vertical direction, but the position adjustment member 16 (gripping mechanism 18) may be a member that cannot be adjusted in the vertical direction. In that case, the position adjustment member 16 may be a member that can grip the sample supply unit 2, and the gripping mechanism 18 that grips the sample supply unit 2 may be any mechanism.

[0057] (I-3) Embodiment 3 The inventors further discovered that when the filter sheet is moistened before being supplied to the filter sheet support member, the filter sheet is more likely to adhere to the support surface of the filter sheet support member, thereby preventing or reducing the inclusion of air in the filtrate.

[0058] That is, the filtration device of embodiment 3 is a filtration device for filtering a fluid sample, and comprises a sample supply section, a filter sheet support member provided below the sample supply section, a suction section that suctions the filtered fluid sample from the opposite side of the sample supply section to the filter sheet supported by the filter sheet support member, and a conveying mechanism that continuously supplies the filter sheet to the filter sheet support member, wherein the support member is a base having a support surface for the filter sheet, and the base is provided with a through hole for suctioning the fluid sample that has passed through the filter sheet by the suction section, and the filter sheet support member is positioned at a position where the filter sheet supported by the filter sheet support member does not come into contact with the sample supply section, and is equipped with a wetting member that wets the filter sheet before the filter sheet is supplied to the filter sheet support member.

[0059] Hereinafter, a filtration device according to embodiment 3 will be described with reference to Fig. 8 and Fig. 2. Fig. 8 is a side view showing a schematic configuration of the filtration device according to embodiment 3. Fig. 2 is a perspective view showing a configuration of a part of the filtration device according to one embodiment of the present invention.

[0060] In the filtering device 1c according to the third embodiment, the sample supplying section 2, the suction section 4, the filter sheet supporting member 3, and the winding device are the same as those in the filtering device according to the first embodiment.

[0061] The wetting member 9 includes a wetting liquid supply unit 10 provided above the filter sheet 7 before it is supplied to the filter sheet support member 3, and a gripping unit 11 that grips the wetting liquid supply unit 10. The wetting liquid supply unit 10 includes a wetting liquid supply port.

[0062] The wetting liquid supply unit 10 is positioned so that it does not come into contact with the filter sheet 7, and the wetting liquid supplied from the wetting liquid supply unit 10 falls and wets the filter sheet 7. As a result, even if the filter sheet 7 contains impurities, the wetting liquid supply unit 10 does not come into contact with the filter sheet 7, so the wetting liquid supply unit 10 is not contaminated. This is therefore preferable because it allows the filter sheet to be cleaned without being contaminated. However, the wetting liquid supply unit 10 may also come into contact with the filter sheet 7.

[0063] The wetting member 9 is disposed upstream of the support member 3 in the filter sheet conveying direction. This allows the filter sheet 7 to be moistened before it is supplied to the filter sheet support member 3. When the pressure guide or guide roller, or the angle adjustment member described above, is disposed upstream of the support member 3 in the filter sheet conveying direction, the wetting member 9 is disposed upstream of the pressure guide or guide roller, or the angle adjustment member described above in the filter sheet conveying direction. This allows wetting the filter sheet 7 and adjusting the angle of the filter sheet 7 with the pressure guide or guide roller, or the angle adjustment member described above, to more effectively prevent or reduce air from being mixed into the filtrate. However, as long as the wetting member 9 can prevent or reduce air from being mixed into the filtrate, it may be disposed between the pressure guide or guide roller, or the angle adjustment member described above, and the support member 3.

[0064] The wetting liquid is not particularly limited as long as it can wet the filter sheet 7, and can be, for example, water. Specifically, pure water or ultrapure water such as ion-exchanged water, ultrafiltered water, reverse osmosis water, or distilled water can be used. The wetting liquid can also be a liquid used as a blank in an analysis. Examples of liquids used as a blank in an analysis include aqueous solutions containing acids such as hydrochloric acid and nitric acid.

[0065] When the same wetting liquid is used for the blank and the analysis, the influence of the wetting liquid on the analysis results can be ignored. Furthermore, when the wetting liquid used for the blank is used as the wetting liquid, the influence on the analysis results can be further reduced.

[0066] The filtration device according to the third embodiment includes a wetting member that wetting the filter sheet before the filter sheet is fed to the filter sheet support member. This not only prevents or reduces the inclusion of air in the filtrate, but also washes away impurities, such as metal elements, that may be contained in the filter sheet. It is known that several metal elements leach from filter paper. Therefore, if the filter paper is not washed, the blank value of the eluted metal elements may increase, adversely affecting the analytical results, especially when analyzing trace amounts. The filtration device according to the third embodiment allows for continuous cleaning of the filter sheet. Therefore, even when analyzing trace amounts, the influence of impurities, such as metal elements, that may be contained in the filter sheet can be reduced, enabling accurate analysis. From the perspective of washing away impurities, such as metal elements, that may be contained in the filter sheet, the wetting liquid may be water, as described above, but is preferably an aqueous solution containing an acid, such as hydrochloric acid or nitric acid, and more preferably a blank solution containing an acid, such as hydrochloric acid or nitric acid. The aqueous solution or blank may contain an acid selected from hydrochloric acid, nitric acid, etc., either singly or in combination of two or more kinds.

[0067] The total concentration of the acid in the aqueous solution containing an acid such as hydrochloric acid or nitric acid is preferably, for example, 0.1% to 10.0%, more preferably 0.1% to 5.0%, and even more preferably 0.2% to 5.0%. Here, the concentration (%) may be a value expressed as (mass (g) of solute / mass (g) of solution)×100 or a value expressed as (mass (g) of solute / volume (mL) of solution)×100.

[0068] The supply flow rate of the wetting liquid supplied from the wetting liquid supply unit 10 is not particularly limited, but is preferably 0.2 mL / min to 10.0 mL / min, more preferably 0.5 mL / min to 5.0 mL / min, and even more preferably 1.0 mL / min to 3.0 mL / min. If the supply flow rate is 0.2 mL / min or more, the filter sheet can be more effectively adhered to the support member. Furthermore, if the supply flow rate is 0.5 mL / min or more, impurities such as metal elements that may be contained in the filter sheet can be more effectively washed away. If the supply flow rate is 10.0 mL / min or less, consumption of the wetting liquid is reduced, which is preferable.

[0069] The configuration of the gripping unit 11 that grips the dampening fluid supply unit 10 is not particularly limited as long as it is capable of gripping the dampening fluid supply unit 10. The gripping unit 11 may be the same as the gripping mechanism 18 described in the second embodiment.

[0070] In the example shown in Fig. 2, the wetting member 9 is provided with a wetting liquid receptacle 19 below the filter sheet 7, so that the waste wetting liquid can be discharged. The wetting liquid receptacle 19 has a bottom plate disposed therein so as to slope downward toward a wetting liquid discharge port (not shown) at the bottom of the receptacle 19, and the waste wetting liquid received by the receptacle 19 is guided to the wetting liquid discharge port by the bottom plate. The configuration of the wetting liquid receptacle 19 is not limited thereto as long as it is capable of discharging the waste wetting liquid. The wetting liquid receptacle 19 may be, for example, a container capable of collecting the waste wetting liquid, and a wetting liquid discharge pipe may be connected to the container so that the waste wetting liquid collected in the receptacle 19 is discharged from the wetting liquid discharge pipe.

[0071] In a filtration device that includes at least an angle adjustment member 15 in addition to the wetting member 9 (described below), it is preferable to adjust the guide roller 14 so that the lowest point where the guide roller 14 and the filter sheet 7 contact is lower than the upstream end of the support surface of the support member 3 in the conveying direction. This creates a pool of wetting liquid near the contact point between the guide roller 14 and the filter sheet 7, through which the filter sheet 7 passes, and is then conveyed upward toward the support surface of the support member 3, thereby preventing the wetting liquid from flowing into the suction section 4 and improving the cleaning effect of the filter sheet 7. In this case, the pressure guide 13 can no longer hold down the filter sheet 7, but because the filter sheet 7 is wet, it is less likely to float from the support surface of the support member 3. In this case, a separate guide roller may be installed between the pressure guide 13 and the support member 3, if necessary. This creates a mechanism that makes it more difficult for air to be mixed in.

[0072] (I-4) Embodiment 4 As shown in FIG. 1, the filtration device according to embodiment 4 is a filtration device 1 for filtering a fluid sample, comprising a sample supply unit 2, a filter sheet support member 3 provided below the sample supply unit 2, a suction unit 4 that suctions the filtered fluid sample from the side opposite the sample supply unit 2 to the filter sheet supported by the filter sheet support member 3, and a conveying mechanism that continuously supplies the filter sheet to the filter sheet support member 3, wherein the support member 3 is a base having a support surface for the filter sheet, and the base is provided with a through hole 6 through which the suction unit 4 suctions the fluid sample that has passed through the filter sheet, and the filter sheet support member 3 is positioned so that the filter sheet supported by the filter sheet support member 3 does not come into contact with the sample supply unit, and the filtration device comprises all of the following configurations (1) to (3).

[0073] (1) Angle adjustment member 15 for adjusting the angle at which the filter sheet is supplied to the support surface of the filter sheet support member; (2) Position adjustment member 16 for adjusting the relative position of the sample supply section and the suction section in the filter sheet transport direction; (3) Wetting member 9 for wetting the filter sheet before it is supplied to the filter sheet support member.

[0074] The filtering device according to the fourth embodiment has the above-described configuration, and can more effectively prevent or reduce the mixing of air into the filtrate.

[0075] In the filtration device 1 of embodiment 4, the sample supply section 2, suction section 4, filter sheet support member 3, winding device, and angle adjustment member 15 are as described in the section on the filtration device of embodiment 1, the position adjustment member 16 is as described in the section on the filtration device of embodiment 2, and the moistening member 9 is as described in the section on the filtration device of embodiment 3.

[0076] (I-5) Other Embodiments The filtration device according to the fourth embodiment has all of the configurations (1) to (3) described above, but a filtration device according to one embodiment of the present invention may have two configurations selected from the configurations (1) to (3) described above, such as (1) and (2), (1) and (3), or (2) and (3).

[0077] (I-6) Use of the Filtration Device The filtration device according to one embodiment of the present invention enables continuous filtration and prevents or reduces the inclusion of air in the filtrate, thereby preventing a decrease in filtration efficiency and adverse effects on analytical results. Therefore, the filtration device according to one embodiment of the present invention can be used for a variety of analyses and can be connected to a wide range of analytical devices, including but not limited to the flow analyzer described below.

[0078] (II) Filtration Method Hereinafter, a filtration method according to one embodiment of the present invention will be described. For the sake of convenience, the details already described for the filtration device in (I) will not be described again.

[0079] A filtration method according to one embodiment of the present invention is a filtration method for filtering a fluid sample, comprising: a step of supplying the fluid sample from a sample supply unit; and a filtration step of filtering the supplied fluid sample with a filter sheet provided below the sample supply unit. In the filtration step, the filtered fluid sample is aspirated from the side opposite the sample supply unit relative to the filter sheet, the sample supply unit and the filter sheet are not in contact, and the filter sheet is continuously transported below the sample supply unit. The filtration method comprises one or more of the following air inclusion prevention steps (1) to (3): (1) an angle adjustment step of adjusting the angle at which the filter sheet is supplied below the sample supply unit; (2) a position adjustment step of adjusting the relative position between the sample supply unit and the suction unit in the filter sheet transport direction; and (3) a wetting step of wetting the filter sheet before it is supplied to the filter sheet support member.

[0080] (III) Flow Analysis Apparatus A flow analysis apparatus according to one embodiment of the present invention will be described below. For the sake of convenience, the matters already described in the filtration apparatus (I) will not be described again.

[0081] [Embodiment 1] A filtering device according to embodiment 1 of the present invention will be described with reference to the drawings. Fig. 10 is a diagram showing a schematic configuration of a flow analyzer 100 according to embodiment 1 of the present invention.

[0082] A flow analysis device 100 according to one embodiment of the present invention includes a sampling device 110, a bubble segmentation device 120, a reagent addition device 130, a heating device 140, a filtration device 1 (or a filtration device 1a, 1b or 1c, the same hereinafter in this specification), and an analysis device 150.

[0083] The sampling device 110 is a device for sampling a sample and introducing it into the pipeline 160. In one embodiment of the present invention, the sampling device 110 includes a collection tube that introduces the sample into the pipeline 160, and a sampling pump that applies suction to the collection tube. The sampling pump introduces the sample into the pipeline 160 at a predetermined flow rate. The sample is a liquid containing a substance or element to be analyzed.

[0084] The bubble segmentation device 120 is a device for performing bubble segmentation on a sample introduced into the conduit 160, creating multiple segments within the conduit 160, each segmented by bubbles. In one embodiment of the present invention, the bubble segmentation device 120 includes a gas inlet pipe for introducing gas into the conduit 160 and a gas introduction pump for applying suction to the gas inlet pipe. By performing bubble segmentation, vortexes within the segmented liquid separated by bubbles can be generated, allowing for efficient mixing of reagents and the like. Furthermore, because the segmented liquid flows through the conduit 160 separated by bubbles, mutual diffusion between samples can be prevented. The gas used for bubble segmentation is preferably air, but may also be an inert gas such as argon or helium, or various gases such as nitrogen and oxygen. These gases may be used alone or in combination. This method, in which a reagent is introduced into a continuous flow in a pipe in which the sample is segmented by bubbles, a reaction operation is carried out, the bubbles are removed, and analysis is carried out using a detector located downstream in the direction of sample flow (hereinafter, in this specification, downstream and upstream in the direction of sample flow may be simply referred to as "downstream" and "upstream", respectively), is called continuous flow analysis (CFA).

[0085] The reagent adding device 130 is a device for adding a reagent to the flow of sample transported along the pipeline 160. The reagent adding device 130 includes a reagent introduction tube that introduces the reagent into the pipeline 160 and a reagent introduction pump that applies suction to the reagent introduction tube. The reagent may be a reagent added during sample pretreatment. Examples of the reagent include, but are not limited to, acids such as hydrogen peroxide, nitric acid, hydrochloric acid, sulfuric acid, perchloric acid, phosphoric acid, and hydrofluoric acid; alkalis such as sodium peroxide, calcium carbonate, and sodium carbonate; and the like.

[0086] The heating device 140 heats the sample transported along the pipeline 160. The heating device 140 may be a thermostatic bath equipped with a heater. However, the configuration of the heating device 140 is not limited thereto and may be an ultrasonic decomposition device, a microwave decomposition device, an autoclave decomposition device, or the like. Furthermore, the pipeline 160 forms a coil or a spiral within the heating device 140. In one embodiment of the present invention, the heating device 140 is provided downstream of the reagent addition device 130. Heating the sample to which the reagent has been added promotes the reaction of the sample with the reagent, thereby enabling pretreatment. In the example of FIG. 10 , the flow analyzer includes a pretreatment unit 170 consisting of one reagent addition device 130 and one heating device 140. However, instead of one reagent addition device 130, multiple reagent addition devices 130 may be provided to add multiple reagents. Furthermore, although the flow analyzer includes one pretreatment unit 170 in the example of FIG. 10 , the flow analyzer may include multiple pretreatment units 170. In such a case, the flow analyzer may be provided with a filtration device 1 for each pretreatment unit 170, and each of the multiple pretreatment units 170 may be provided with a different number of reagent addition devices 130. By providing multiple pretreatment units 170, it is possible to perform pretreatment in the form of, for example, acid decomposition under heating, followed by adding acid again and performing acid decomposition under heating. When multiple reagent addition devices 130 are provided, the reagents added by each reagent addition device 130 may be the same or different.

[0087] 10, the reagent addition device 130 is provided downstream of the bubble segmentation device 120, but the location of the reagent addition device 130 is not limited to this. The reagent addition device 130 may be provided upstream of the bubble segmentation device 120. Alternatively, the reagent addition device 130 may be provided downstream of the heating device 140. Alternatively, one or more reagent addition devices 130 for introducing reagents used in pretreatment may be provided upstream of the heating device 140, and one or more reagent addition devices 130 may be provided downstream of the heating device 140.

[0088] The filtration device 1 filters a sample (fluid sample) to which a reagent has been added and which has been heated. Details of the filtration device 1 are as described in (I). By using the filtration device 1 to remove insoluble components from the fluid sample, it is possible to prevent the insoluble components from clogging the pipeline 160 and / or the downstream analysis device 150, making the analysis impossible. The filtered fluid sample is supplied to the analysis device 150, allowing the analysis device 150 to properly analyze the filtered fluid sample. Furthermore, in the example of FIG. 10, the filtration device 1 is provided downstream of the heating device 140, but the location of the filtration device 1 is not limited thereto. The filtration device 1 may also be provided upstream of the bubble segmentation device 120.

[0089] The analytical device 150 is a device that performs analysis on the filtered fluid sample. In one embodiment of the present invention, the analytical device 150 is an inductively coupled plasma mass spectrometer (ICP-MS). However, the analytical device 150 is not limited to this and may be any analytical device, for example, an atomic absorption spectrometer, an inductively coupled plasma optical emission spectrometer (ICP-OES), an inductively coupled plasma triple quadrupole mass spectrometer, an ion electrode meter, or a spectrophotometer. Furthermore, the analytical device 150 is not limited to a device for measuring the presence or concentration of metal elements, and the object to be measured is not particularly limited. Furthermore, the analysis may be quantitative or qualitative.

[0090] According to the flow analysis device of the above-mentioned embodiment 1, a sample can be continuously introduced into the pipeline 160, bubbles can be segmented, a reagent can be introduced, the reaction can be promoted by the heating device, the fluid sample can be filtered by the filtering device, and analytical data can be continuously measured by the analyzing device.

[0091] In the first embodiment described above, the flow analyzer includes the reagent addition device 130 and the heating device 140. However, the flow analyzer does not necessarily need to include the reagent addition device 130 and the heating device 140, and may be configured without either the reagent addition device 130 or the heating device 140. When analyzing a sample that does not require pretreatment or a sample that has already been pretreated, the flow analyzer may be configured without either the reagent addition device 130 or the heating device 140. Even in such a case, the flow analyzer includes the filtration device 1. Alternatively, the flow analyzer may be configured with only the heating device 140 and without the reagent addition device 130, or conversely, the flow analyzer may be configured with only the reagent addition device 130 and without the heating device 140. Even in such a case, the flow analyzer includes the filtration device 1. For example, when a sample to which a reagent such as an acid or alkali has been added in advance is introduced into the pipeline 160, or when pretreatment requires heating but no reagent, the flow analyzer may be configured with only the heating device 140 and without the reagent addition device 130. Which configuration should be used may be selected appropriately depending on the sample pretreatment method.

[0092] In an embodiment that does not include either the reagent addition device 130 or the heating device 140, the flow analysis device is a flow analysis device that includes a sampling device 110 for introducing a fluid sample into a pipeline 160, and an analysis device 150 for performing analysis on the sample transported through the pipeline 160, and further includes a filtration device 1 for filtering the fluid sample.

[0093] Although not provided in the example of FIG. 10 , the flow analyzer according to one embodiment of the present invention may further include a pool tank (liquid reservoir) in the pipeline 160. Because the flow analyzer performs analysis by flowing a sample through an enclosed space, pressure may build up. Even in such cases, the provision of a pool tank allows pressure to be released and the volume required for each step to be appropriately dispensed and collected. The pool tank may be located anywhere in the pipeline 160, but is preferably located downstream of the heating device 140, more preferably between the heating device 140 (or the most downstream heating device 140 if multiple heating devices 140 are provided) and the analyzer 150. In addition to the pool tank, other means for releasing pressure within the flow analyzer may include, for example, a debubbler for discharging appropriate amounts of air (gas) and liquid, a pressure reducing valve, or the like.

[0094] Furthermore, the flow analyzer according to one embodiment of the present invention may include a pressure device that applies pressure against the flow of the sample from the downstream side of the heating device 140. The pressure device may include, for example, a compressor and a valve. By including such a pressure device, it is possible to suppress the expansion of bubbles in the heating device 140 and promote the reaction in the heating device 140 due to the synergistic effect of heating and pressurization. The pressure applied by the pressure device is not particularly limited, but is, for example, 0.14 MPa or less.

[0095] In addition, in the flow analyzer according to one embodiment of the present invention, an autosampler can be used as the sampling device 110. Furthermore, an ultrasonic homogenizer or a stirrer may be provided to crush and / or stir the sample before sampling.

[0096] Alternatively, the flow analyzer according to one embodiment of the present invention may further include a dilution device in the pipeline 160. This allows the desired dilution to be performed automatically within the flow analyzer when dilution is required depending on the concentration of the sample. The dilution device is not particularly limited, but a commercially available automatic dilution device, for example, can be suitably used.

[0097] Furthermore, the flow analyzer according to one embodiment of the present invention may be an apparatus incorporating an apparatus for pretreating non-liquid samples, such as solids, to prepare a liquid sample into the sampling device 110 or an apparatus incorporating the apparatus upstream of the sampling device 110. A flow analyzer is an apparatus for analyzing liquid samples using flow analysis, and cannot directly measure non-liquid samples, such as solids. Therefore, by incorporating an apparatus for pretreating non-liquid samples, such as solids, to prepare a liquid sample, it is possible to perform a complete process from pretreatment to analysis of non-liquid samples, such as solids. Such an apparatus is more preferably an apparatus for fully automatically pretreating non-liquid samples, such as solids. For example, a fully automatic acid decomposition pretreatment apparatus that automatically performs reagent addition, mixing, heating, and filling can be suitably used.

[0098] In this embodiment, the flow analyzer is an analyzer that uses a CFA, but is not limited to a CFA and is not particularly limited.

[0099] 11 is a diagram showing a schematic configuration of a flow analyzer 300 according to a second embodiment of the present invention. For ease of explanation, components having the same functions as those described for the flow analyzer according to the first embodiment are denoted by the same reference numerals, and their description will not be repeated.

[0100] In addition to the configuration of the flow analysis apparatus 100 according to the first embodiment described above, the flow analysis apparatus 300 according to the second embodiment of the present invention further includes a marker introduction device 180, a high-temperature, high-pressure decomposition device 190, a suspended matter collection cartridge 200, a surfactant addition device 210, a mixing coil 220, a marker detection device 230, and a degassing device 240. Furthermore, a bubble segmentation device 120 is further included between the sampling device 110 and the high-temperature, high-pressure decomposition device 190, and between the suspended matter collection cartridge 200 and the surfactant addition device 210.

[0101] Marker introducer 180 is a device for introducing a marker into conduit 160. In one embodiment of the present invention, marker introducer 180 includes a collection tube that introduces the marker into conduit 160, and a pump that applies suction to the collection tube. The marker only needs to contain a substance that can be detected by marker detector 230, and may be the substance itself, a solution containing the substance, or a dispersion containing the substance.

[0102] Here, the marker introduction device 180 and the sampling device 110 are capable of alternately introducing the marker and one or more predetermined number of samples into the pipeline 160. That is, the introduction of the marker from the marker introduction device 180 into the pipeline 160 and the introduction of one or more predetermined number of samples from the sampling device 110 into the pipeline 160 can be alternately switched. This switching may be performed manually or automatically.

[0103] In the case where the marker and one sample can be introduced alternately into the conduit 160, the marker is introduced into the conduit 160 before each sample. Then, for each sample, the marker detection device 230 that detects the marker outputs a marker detection signal to the analyzer 150, and the analyzer 150 acquires analysis data based on the detection signal. As a result, even if the liquid cannot be transferred stably and uniformly from the introduction of the sample to the analyzer, the timing of acquiring the analysis data does not deviate, and the sample can be measured stably and continuously.

[0104] Furthermore, when the marker and two or more predetermined number of samples can be introduced alternately into the conduit 160, the marker is introduced into the conduit 160 once before the two or more predetermined number of samples. Then, the marker detection device 230 detects the marker and outputs a marker detection signal to the analyzer 150. Based on the detection signal, the analyzer 150 sequentially acquires analytical data for the predetermined number of samples. This reduces the timing lag in analytical data acquisition to a certain range, even when sample delivery from introduction to the analyzer is not stable and uniform, enabling stable and continuous sample measurement. The upper limit of the predetermined number may be appropriately selected depending on the type of sample, the pretreatment method, etc., and may be, for example, 80, 77, 50, 20, 15, or 10.

[0105] The marker detectable by the marker detection device 230 is not particularly limited, but is preferably a substance not contained in the sample. Furthermore, the marker is preferably a substance that is not decomposed by a reagent or heat added between the introduction into the pipeline 160 and the marker detection device 230. For example, the marker may be a substance detectable by a spectrophotometer. Examples of such substances include, but are not limited to, rhodium, nickel, copper, chromium, manganese, iodine, cobalt, nitrate ions, phosphate ions, and silicate ions. Alternatively, the substance may be a substance detectable by a voltammetry meter. Examples of such substances include, but are not limited to, copper, cadmium, nickel, mercury, arsenic, and selenium. Alternatively, the substance may be a substance detectable by an ion electrode meter. Examples of such substances include, but are not limited to, calcium, potassium, fluorine, and ammonia. Alternatively, the substance may be a substance detectable by ion chromatography. Such substances are not particularly limited, and examples thereof include ions of inorganic and organic acids, phenols, hydrazines, amino acids, and polysaccharides. Alternatively, the substances may be substances that can be detected with a turbidimeter. Such substances are not particularly limited, and examples thereof include silica, which is a particulate substance that does not dissolve in acids other than hydrofluoric acid. Alternatively, the substances may be substances that can be detected with a fluorometer. Such substances are not particularly limited, and examples thereof include benzene, coumarin, and naphthalene. Among these, rhodium, cobalt, nickel, copper, and the like are particularly preferred markers due to their ease of detection.

[0106] The high-temperature, high-pressure decomposition device 190 is a device for pre-processing, in which metal components are dissolved and organic matter, suspended matter, metal complexes, and the like coexisting in the sample are decomposed. The high-temperature, high-pressure decomposition device 190 separates the sample into a waste liquid and a sample from which the waste liquid has been removed. The high-temperature, high-pressure decomposition device 190 discharges the waste liquid and supplies the sample from which the waste liquid has been removed to the pipeline 160.

[0107] The suspended matter collection cartridge 200 is a device for removing residue of the filter sheet 7 from the filtered fluid sample. Depending on the material of the filter sheet 7, residue of the filter sheet 7 may be mixed into the filtered fluid sample. In this case, the suspended matter collection cartridge 200 removes the residue of the filter sheet 7 from the filtered fluid sample, thereby preventing clogging and contamination of the marker detection device 230 and the analysis device 150 due to the mixture of the residue.

[0108] In this embodiment, the filtering device 1 is disposed between the heating device 140 and the suspended matter collection cartridge 200. However, the location of the filtering device 1 is not limited to this, and it may be disposed between the sampling device 110 and the analysis device 150. The filtering device 1 may be disposed appropriately depending on the type of analysis device 150, and may be disposed, for example, between the sampling device 110 and the bubble segmentation device 120, or between the marker detection device 230 and the degassing device 240.

[0109] The suspended matter collection cartridge 200 is not particularly limited as long as it can collect residue from the filter sheet 7 and does not contaminate the filtered fluid sample. For example, quartz wool, cellulose, etc. can be used as the suspended matter collection cartridge 200.

[0110] The surfactant adding device 210 is a device for adding a surfactant to a fluid sample. Adding a surfactant to a fluid sample allows the liquid to flow stably, prevents adhesion of dirt, and makes it less likely for clogging to occur inside the conduit 160.

[0111] The mixing coil 220 is a device for mixing the fluid sample and the surfactant. When the fluid sample and the surfactant, which have different liquid properties, pass through the spirally wound mixing coil 220, agitation occurs, allowing the fluid sample and the surfactant to be mixed.

[0112] The marker detection device 230 and the analysis device 150 are arranged in series. After the sample pretreatment is completed but before it is introduced into the analysis device 150, the marker detection device 230 continuously measures the liquid introduced from the pipeline 160, and if it detects the marker, it outputs a detection signal to the analysis device 150. Then, after receiving the detection signal, the analysis device 150 starts acquiring analysis data. In this case, the timing at which the analysis data acquisition starts can be adjusted so that the analysis device 150 can measure the sample that has arrived. For example, the analysis device 150 can be set to start acquiring analysis data a predetermined time after receiving the detection signal.

[0113] In one embodiment of the present invention, the marker detection device 230 is a spectrophotometer. If the marker contains rhodium, the marker detection device 230 outputs a detection signal to the analysis device 150 when rhodium is detected. However, the marker detection device 230 is not limited to a spectrophotometer and may be, for example, a voltammetry meter, an ion electrode meter, an ion chromatograph, a turbidimeter, or a fluorometer. The marker and the sample flowing sequentially are introduced into the analysis device 150 and the marker detection device 230 at the same time from the pipeline 160 and the branch pipe, respectively. Alternatively, the timing at which the marker and the sample flowing sequentially are introduced into the analysis device 150 and the marker detection device 230 may be different from each other. In this case, the marker and the sample flowing sequentially need to be introduced into the marker detection device 230 at an earlier timing than the analysis device 150. Furthermore, in the above embodiment, the analysis device 150 starts acquiring analysis data upon receiving the detection signal. However, the analysis device 150 may be configured to start acquiring analysis data a predetermined time after receiving the detection signal.

[0114] In one embodiment of the present invention, the analysis device 150 and the marker detection device 230 are arranged in series as described above. However, the analysis device 150 and the marker detection device 230 may also be arranged in parallel.

[0115] The degassing device 240 is a device for discharging the air bubbles that have separated the segments. The degassing device 240 is equipped with a degassing pipe that discharges the air bubbles from the conduit 160 and a degassing pump that determines the speed at which the air bubbles are discharged. The degassing device 240 discharges the air bubbles, thereby preventing air bubbles from getting mixed into the analyzer 150.

[0116] In the above-described second embodiment, the flow analyzer includes a high-temperature, high-pressure decomposition device 190, a reagent addition device 130, a heating device 140, a suspended matter collection cartridge 200, a surfactant addition device 210, and a mixing coil 220. However, the flow analyzer does not necessarily need to include all of these, and may be configured to include at least one of these, or none of them.

[0117] 12 is a diagram showing a schematic configuration of a flow analyzer 400 according to a third embodiment of the present invention. For ease of explanation, components having the same functions as those described in the flow analyzers according to the first and second embodiments are denoted by the same reference numerals, and their description will not be repeated.

[0118] The flow analysis device 400 of embodiment 3 of the present invention includes a sampling device 110, a filtration device 1, a first reagent addition device 130, a first bubble segmentation device 120, a first mixing coil 220, a degassing device 240, a second bubble segmentation device 120, a second reagent addition device 130, a second mixing coil 220, a third reagent addition device 130, a third mixing coil 220, and an analysis device 150.

[0119] In the third embodiment, first, the first reagent is introduced into the conduit 160 by the first reagent adding device 130 .

[0120] A first bubble splitting device 120 is provided downstream of the first reagent adding device 130 and performs bubble splitting on the first reagent introduced into the pipeline 160 .

[0121] On the other hand, in embodiment 3, the sampling device 110 samples a sample and supplies it to the filtration device 1. The sampling device 110 includes a collection tube that introduces the sample to the filtration device 1 and a sampling pump that applies suction to the collection tube. The sampling pump supplies the sample to the filtration device 1 at a predetermined flow rate. The sample (fluid sample) supplied to the filtration device 1 is filtered by the filtration device 1. The sample, from which insoluble components of a certain particle size or larger have been removed by the filtration device 1, is introduced into the flow of the first reagent, which has been bubble-divided by the bubble-dividing device 120 and is being transported through the filtration device 160, by a sample introduction tube that introduces the sample to the filtration device 160 and a sample introduction pump that applies suction to the reagent introduction tube.

[0122] After the sample is introduced into the bubble-separated first reagent flowing in the conduit 160, the flow in the conduit 160 is agitated as it passes through the first mixing coil 220, mixing the sample and the first reagent.

[0123] A degasser 240 is provided downstream of the first mixing coil 220 to remove air bubbles that have separated the segments.

[0124] A second bubble splitter 120 is provided downstream of the degasser 240, and performs bubble splitting again on the sample from which bubbles have been removed.

[0125] Downstream of the second bubble segmentation device 120, a second reagent addition device 130 and a second mixing coil 220, and a third reagent addition device 130 and a third mixing coil 220 are provided in this order, and the second reagent and the third reagent are added to and mixed with the sample being transported through the pipeline 160.

[0126] The sample to which the second and third reagents have been added and mixed is transferred to the analysis device 150 and analyzed.

[0127] The flow analyzer according to the third embodiment can be suitably used, for example, in the hydrochloric acid acid naphthylethylenediamine color reaction CFA method according to JIS K0170 (2019) Part 2, Nitrite Nitrogen, 6.3.5. In such a case, the first reagent may be imidazole, the second reagent may be sulfanilamide, and the third reagent may be N-1 naphthylethylenediamine. The sample and these reagents are mixed at room temperature, color developed, and the absorbance at 545 nm is measured to quantitatively analyze nitrite nitrogen. A spectrophotometer can be used as the analyzer.

[0128] However, in this embodiment, the device configuration and reagents used are not limited to those described above, and can be changed as appropriate depending on the subject of analysis, etc.

[0129] Furthermore, the flow analyzer according to one embodiment of the present invention is not limited to the above-described embodiments 1, 2, and 3, and may be, for example, a flow analyzer described in Patent Application No. 2021-100387, WO2021 / 153442, WO2023 / 188091, etc., equipped with a filtration device according to one embodiment of the present invention.

[0130] (IV) Flow Analysis Method Hereinafter, a flow analysis method according to one embodiment of the present invention will be described. For the sake of convenience, the matters already described in (I) Filtration Device, (II) Filtration Method, and (III) Flow Analysis Device will not be described again.

[0131] A flow analysis method according to one embodiment of the present invention includes a sample introduction step of introducing a sample into a pipeline and an analysis step of analyzing the sample transported through the pipeline, and includes a filtration step of performing filtration by the filtration method (II) described above.

[0132] The sample introduction step is a step of introducing samples into a pipeline, and involves, for example, sampling a plurality of samples using a sampling device and introducing them into the pipeline in succession at a predetermined flow rate.

[0133] The analysis step is a step of analyzing the sample transported along the pipeline. Here, the analysis includes detecting the presence or absence of an analyte or measuring its concentration. The analysis may be quantitative or qualitative. The analysis method is not particularly limited and may be any analysis, such as atomic absorption spectrometry, inductively coupled plasma optical emission spectroscopy, inductively coupled plasma mass spectrometry, inductively coupled plasma triple quadrupole mass spectrometry, ion electrode analysis, or spectrophotometric analysis.

[0134] The subject of analysis is not particularly limited, and may be, for example, a method for measuring the concentration of a metal element.

[0135] Furthermore, the flow analysis method according to one embodiment of the present invention may include a marker introduction step, between a sample introduction step and the next sample introduction step, of introducing a marker into the conduit 160. Here, the marker introduction step and the sample introduction step are preferably performed such that the marker and one or more predetermined number of samples are introduced alternately into the conduit.

[0136] Furthermore, the flow analysis method according to one embodiment of the present invention may include a high-temperature, high-pressure decomposition step in which a high-temperature, high-pressure decomposition process is performed on the sample being transported along the pipeline. The heating temperature, pressure, and time in the high-temperature, high-pressure decomposition step may be appropriately selected depending on the target of analysis, etc., and are not particularly limited. The heating temperature is, for example, 110°C to 130°C, the pressure is, for example, 0.11 MPa to 0.15 MPa, and the time is, for example, 15 minutes to 25 minutes.

[0137] Furthermore, the flow analysis method according to one embodiment of the present invention may include a reagent addition step of adding a reagent into the flow of the sample transported along the pipeline.

[0138] Furthermore, the flow analysis method according to one embodiment of the present invention may include a heating step in which a sample transported along the pipeline is subjected to a heat treatment. In such a case, the analysis step is performed on the sample after the heat treatment. The heating temperature and heating time in the heating step may be appropriately selected depending on the analysis target, pretreatment method, etc., and are not particularly limited. The heating temperature is, for example, 25°C to 150°C, and the heating time is, for example, 5 minutes to 1 hour.

[0139] Furthermore, the flow analysis method according to one embodiment of the present invention may include a suspended matter collection step of collecting residue of the filter sheet from the fluid sample transported along the pipeline.

[0140] Furthermore, the flow analysis method according to one embodiment of the present invention may include a surfactant addition step of adding a surfactant to the fluid sample being transported along the pipeline.

[0141] Furthermore, the flow analysis method according to one embodiment of the present invention may include a mixing step of mixing the fluid sample transported along the pipeline with the surfactant added in the surfactant addition step.

[0142] Furthermore, the flow analysis method according to one embodiment of the present invention may include a marker detection step of detecting a marker and outputting a detection signal to an analysis device. In such a case, the analysis step acquires analysis data based on the detection signal.

[0143] Furthermore, the flow analysis method according to one embodiment of the present invention may include a degassing step for expelling air bubbles that have separated the segments.

[0144] <Summary> One embodiment of the present invention includes the following configuration.

[0145] [1] A filtration device for filtering a fluid sample, comprising: a sample supply unit; a filter sheet support member provided below the sample supply unit; a suction unit that suctions the filtered fluid sample from the opposite side of the sample supply unit to a filter sheet supported by the filter sheet support member; and a transport mechanism that continuously supplies the filter sheet to the filter sheet support member, wherein the support member is a base having a support surface for the filter sheet, and the base is provided with a through-hole for suctioning the fluid sample that has passed through the filter sheet by the suction unit, and the filter sheet support member is arranged at a position where the filter sheet supported by the filter sheet support member does not come into contact with the sample supply unit, and the filtration device is provided with one or more of the following air intrusion prevention mechanisms (1) to (3): (1) an angle adjustment member that adjusts the angle at which the filter sheet is supplied to the support surface of the filter sheet support member; (2) a position adjustment member that adjusts the relative position of the sample supply unit and the suction unit in the filter sheet transport direction; (3) A wetting member that wets the filter sheet before the filter sheet is fed to the filter sheet support member.

[0146] [2] The filtering device described in [1], wherein the wetting member comprises a wetting liquid supply portion provided above the filter sheet before it is supplied to the filter sheet support member, and a gripping portion for gripping the wetting liquid supply portion.

[0147] [3] The angle adjustment member comprises an arm having a pressure guide attached to one end that presses the filter sheet downward and a guide roller attached to the other end, and an angle adjustment mechanism, the arm is arranged so that the pressure guide is located downstream in the conveying direction relative to the guide roller, the arm is rotatably fixed to the frame at the point where the pressure guide is attached so that the pressure guide is positioned on an extension line of the support surface of the filter sheet support member toward the upstream side in the conveying direction, and is rotatable on a plane perpendicular to the filter sheet, with the point where the pressure guide is attached as the center of the rotation axis, a filtration device described in [1] or [2].

[0148] [4] A filtration device described in any one of [1] to [3], wherein the position adjustment member is a member that grips the sample supply section so as to be movable along the conveying direction of the filter sheet.

[0149] [5] A filtration device described in any of [1] to [4], wherein the support surface of the filter sheet support member for the filter sheet is inclined from top to bottom from the source of the filter sheet to the destination of the filter sheet.

[0150] [6] A filtration device described in any of [1] to [5], wherein the conveying mechanism includes a roll on which the filter sheet is wound into a roll and a winding device, and the rolled filter sheet is wound by the winding device, thereby enabling continuous conveyance.

[0151] [7] A flow analysis device including a sampling device for introducing a sample into a pipeline and an analysis device for analyzing the sample transported through the pipeline, the flow analysis device including the filtration device described in any one of [1] to [6].

[0152] [8] A filtration method for filtering a fluid sample, comprising: a step of supplying the fluid sample from a sample supply unit; and a filtration step of filtering the supplied fluid sample with a filter sheet provided below the sample supply unit, wherein in the filtration step, the filtered fluid sample is sucked by a suction unit from the opposite side of the filter sheet from the sample supply unit, the sample supply unit and the filter sheet are not in contact with each other, and the filter sheet is continuously transported below the sample supply unit; and the filtration method comprises one or more of the following air inclusion prevention steps (1) to (3): (1) an angle adjustment step of adjusting the angle at which the filter sheet is supplied below the sample supply unit; (2) a position adjustment step of adjusting the relative position of the sample supply unit and the suction unit in the filter sheet transport direction; and (3) a wetting step of wetting the filter sheet before it is supplied below the sample supply unit.

[0153] [9] The filtration method described in [8], wherein the filter sheet is inclined from top to bottom from the source of transport to the destination of transport.

[0154]

[10] A flow analysis method including a sample introduction step of introducing a sample into a pipeline and an analysis step of analyzing the sample transported through the pipeline, the flow analysis method including a filtration step of filtering by the filtration method described in [8] or [9].

[0155] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

[0156] Example 1 Using the filtration device shown in Figure 6, the angle α between the upper surface of the filter sheet 7 on the upstream side of the pressure guide 13 in the filter sheet conveying direction and the support surface was adjusted using the angle adjustment member 15. When α was set to 100 degrees and 145 degrees, pure water was filtered, and the amount of air mixed into the filtrate was observed and the amount of filtrate was measured. Specifically, filtration was performed by operating the filtration device for 1 minute and 10 minutes, during which time the amount of air mixed in was visually observed and the amount of filtrate was measured. The supply flow rate of the fluid sample supplied from the sample supply unit was 1.4 mL / min, the suction flow rate of the fluid sample sucked through the filter sheet was 1.2 mL / min, and the conveying speed of the filter sheet was 4.0 cm / min. The width of the filter sheet and the support member was 25 mm, the inclination angle of the filter sheet and the support member was 9.6 degrees, the inner diameter of the through-hole was 1.0 mm, the outer diameter of the suction portion was 3.0 mm, and the inner diameter of the suction portion was 1.0 mm. As the filter material sheet, a filter paper sheet (JIS P3801, for quantitative analysis, type 5B) was used.

[0157] When α was set to 145°C, no air was observed mixing into the filtrate during 1-minute and 10-minute runs. In contrast, when α was set to 100°C, air was observed mixing into the filtrate during 1-minute and 10-minute runs. Table 1 shows the results of measuring the filtrate volume after five 1-minute runs and one 10-minute run. In Table 1, the theoretical filtrate volume is calculated from the suction flow rate of 1.2 mL / min of the fluid sample sucked through the filter sheet.

[0158] Example 1 showed that the angle adjustment member can be used to adjust the angle α between the upper surface of the filter sheet 7 on the upstream side of the pressure guide 13 in the filter sheet conveying direction and the support surface, thereby preventing air from being mixed into the filtrate.

[0159] Furthermore, as shown in Table 1, when air was mixed into the filtrate, the filtrate volume decreased and the coefficient of variation (RSD) of the filtrate volume increased. These results show that by using the angle adjustment member to prevent air from mixing into the filtrate, it is possible to prevent a decrease in filtration efficiency and adverse effects on the analysis results.

[0160] Example 2 Using the filtration device shown in Figure 7, the relative positions of the sample supply unit 2 and the suction unit 4 in the filter sheet conveyance direction were adjusted using the position adjustment member 16. Specifically, pure water was filtered and the presence of air in the filtrate was visually observed when the sample supply unit 2 was positioned directly above the suction unit 4 and when the sample supply unit 2 was positioned upstream of the suction unit 4 in the conveyance direction, with the distance between the position where the fluid sample was supplied from the sample supply unit 2 (the position where the fluid sample fell) and the position of the suction unit 4 being 3.0 mm. The supply flow rate of the fluid sample supplied from the sample supply unit was 1.4 mL / min, the suction flow rate of the fluid sample sucked through the filter sheet was 1.2 mL / min, and the conveyance speed of the filter sheet was 4.0 cm / min. The width of the filter sheet and the support member was 25 mm, the inclination angle of the filter sheet and the support member was 9.4 degrees, the inner diameter of the through-hole was 3.05 mm, the outer diameter of the suction unit was 3.0 mm, and the inner diameter of the suction unit was 1.0 mm. The filter sheet used was a filter paper sheet (JIS P3801, for quantitative analysis, type 5B). The distance between the sample supply port of the sample supply unit 2 and the support surface of the filter sheet support member 3 was 2.0 mm.

[0161] When the sample supply unit was located upstream of the suction unit in the conveying direction, no air was observed mixing into the filtrate. In contrast, when the sample supply unit was located directly above the suction unit, air was observed mixing into the filtrate. This indicates that air can be prevented from mixing into the filtrate by using the position adjustment member to adjust the relative positions of the sample supply unit and the suction unit in the conveying direction of the filter sheet.

[0162] Example 3: Using a flow analyzer equipped with the filtration device shown in Figure 8 as a filtration device, metal ion count intensities in a blank solution were measured using continuous flow analysis (CFA) and inductively coupled plasma mass spectrometry (ICP-MS). The filtrate was visually observed for air inclusions and measured for metal ion count intensities when the filter sheet was wetted before being supplied to the filter sheet support member and when the filter sheet was not wetted. The supply flow rate of the fluid sample supplied from the sample supply unit was 1.4 mL / min, the suction flow rate of the fluid sample sucked through the filter sheet was 1.2 mL / min, and the filter sheet conveyance speed was 4.0 cm / min. The width of the filter sheet and support member was 25 mm, the inclination angle of the filter sheet and support member was 9.4 degrees, the inner diameter of the through-hole was 3.05 mm, the outer diameter of the suction section was 3.0 mm, and the inner diameter of the suction section was 1.7 mm. The filter sheet used was a filter paper sheet (JIS P3801, for quantitative analysis, type 5B). The analytical device used was an inductively coupled plasma mass spectrometer.

[0163] A 5% nitric acid solution was used as the blank solution. The same 5% nitric acid solution was used as the wetting liquid. The supply flow rate of the wetting liquid supplied from the wetting liquid supply unit was 1.0 mL / min.

[0164] As described above, when the filter sheet was moistened, no air was observed to be mixed into the filtrate. In contrast, when the filter sheet was not moistened, air was observed to be mixed into the filtrate. This indicates that by moistening the filter sheet with the moistening member before it is supplied to the filter sheet support member, it is possible to prevent air from being mixed into the filtrate.

[0165] Table 2 shows the results of measuring the metal ion count intensity when the filter sheet was wetted and when the filter sheet was not wetted. Table 2 shows only metals whose ion count intensity increased when a filtration device was installed. Table 2 also shows the results of quantifying metals without a filtration device as reference data.

[0166] As shown in Table 2, by providing a wetting member in the filtration device and cleaning the filter sheet, the ion count of the blank solution was significantly reduced. These results show that the wetting member was able to wash away impurities such as metal elements that may be contained in the filter sheet. It is clear that cleaning the filter sheet with a wetting member is useful in analyzing trace amounts of metals, where the amount of metal eluted from the filter sheet affects the measurement results.

[0167] The filtration device and filtration method according to one embodiment of the present invention can be used in the analytical field.

[0168] DESCRIPTION OF SYMBOLS 1, 1a, 1b, 1c Filtration device 2 Sample supply unit 3 Support member 4 Suction unit 5 Frame 6 Through-hole 7 Filter medium sheet 8 Filter medium sheet roll 9 Wetting member 10 Wetting liquid supply unit 11 Grip unit 12 Arm 13 Pressing guide 14 Guide roller 15 Angle adjustment member 16 Position adjustment member 17 Guide hole 18 Grip mechanism (gripping member) 19 Wetting liquid receiver 21 Fixing device (fixing screw) 22 Fixing device (fixing screw) 100, 300, 400 Flow analysis device 110 Sampling device 120 Bubble segmentation device 130 Reagent addition device 140 Heating device 150 Analysis device 180 Marker introduction device 190 High-temperature, high-pressure decomposition device 200 Suspension collection cartridge 210 Surfactant addition device 220 Mixing coil 230 Marker detection device 240 Degassing device

Claims

1. A filtration device for filtering a fluid sample, comprising: a sample supply unit; a filter medium sheet support member provided below the sample supply unit; a suction unit that sucks the filtered fluid sample from the side opposite to the sample supply unit with respect to the filter medium sheet supported by the filter medium sheet support member; a transport mechanism that continuously supplies a filter medium sheet to the filter medium sheet support member, wherein the filter medium sheet support member is a pedestal having a support surface for the filter medium sheet, and the pedestal is provided with through holes for sucking the fluid sample that has passed through the filter medium sheet by the suction unit, and the filter medium sheet support member is arranged at a position where the filter medium sheet supported by the filter medium sheet support member and the sample supply unit do not come into contact with each other, and the filtration device further comprises one or more air intrusion prevention mechanisms of the following (1) to (3): (1) an angle adjustment member that adjusts the angle at which the filter medium sheet is supplied to the support surface of the filter medium sheet support member; (2) a position adjustment member that adjusts the relative position in the filter medium sheet transport direction between the sample supply unit and the suction unit; (3) a wetting member that wets the filter medium sheet before the filter medium sheet is supplied to the filter medium sheet support member.

2. The filtration device according to claim 1, wherein the wetting member comprises a wetting liquid supply unit provided above the filter medium sheet before the filter medium sheet is supplied to the filter medium sheet support member, and a gripping unit that grips the wetting liquid supply unit.

3. The filtration device according to claim 1, wherein the angle adjustment member comprises an arm having a pressing guide for pressing the filter medium sheet downward attached to one end and a guide roller attached to the other end, and an angle adjustment mechanism, the arm is arranged such that the pressing guide is located downstream in the transport direction with respect to the guide roller, and the arm is rotatably fixed to the frame at the location where the pressing guide is attached such that the pressing guide is arranged on an extension line of the support surface of the filter medium sheet support member upstream in the transport direction, and is rotatable on a plane perpendicular to the filter medium sheet with the location where the pressing guide is attached as the center of the rotation axis.

4. The filtration device according to claim 1, wherein the position adjustment member is a member that grips the sample supply unit so as to be movable along the transport direction of the filter medium sheet.

5. The filter sheet support member according to claim 1, wherein the support surface for the filter sheet is inclined downward from above in the direction from the conveyance source to the conveyance destination of the filter sheet.

6. The filtration device according to claim 1, wherein the conveyance mechanism includes a roll around which the filter sheet is wound in a roll shape and a winding device, and the filter sheet wound in a roll shape can be continuously conveyed by being wound by the winding device.

7. A flow analysis device including a sampling device for introducing a sample into a pipeline and an analysis device for analyzing the sample transferred in the pipeline, the flow analysis device including the filtration device according to any one of claims 1 to 6.

8. A filtration method for filtering a fluid sample, including a step of supplying the fluid sample from a sample supply unit, and a filtration step of filtering the supplied fluid sample with a filter sheet provided below the sample supply unit. In the filtration step, the filtered fluid sample is sucked by a suction unit from the side opposite to the sample supply unit with respect to the filter sheet. The sample supply unit and the filter sheet are not in contact with each other, and the filter sheet is continuously conveyed below the sample supply unit. The filtration method includes one or more air entrainment prevention steps of the following (1) to (3): (1) an angle adjustment step of adjusting the angle at which the filter sheet is supplied below the sample supply unit; (2) a position adjustment step of adjusting the relative position in the filter sheet conveyance direction between the sample supply unit and the suction unit; (3) a wetting step of wetting the filter sheet before the filter sheet is supplied below the sample supply unit.

9. The filtration method according to claim 8, wherein the filter sheet is inclined downward from above in the direction from the conveyance source to the conveyance destination.

10. A flow analysis method including a sample introduction step of introducing a sample into a pipeline and an analysis step of analyzing the sample transferred in the pipeline, the flow analysis method including a filtration step of performing filtration by the filtration method according to claim 8 or 9.

Images