Target liquid purification device

Abstract

The purpose of the present invention is to provide a target liquid purification device with which it is possible, while reliably performing dialysis and reducing the total amount of dialysate used in the dialysis, to accurately measure the concentration of a target substance in blood despite having a structure that is simple and so safe so as not to affect the human body without any blood being collected.　A target liquid purification device according to the present invention comprises a body 1, a concentration measurement device 2, a control device 3, and a notification device 4. The body 1 is provided with a separation device 100, an unpurified target liquid passage 11, a purified target liquid passage 12, a filtered dialysate passage 21, a dialysate passage 412, a drainage passage 24, a first flow rate adjustment device 36, and a concentration sensor 35 for outputting a signal that corresponds to the concentration of a target substance in the target liquid. The concentration measurement device 2 measures the concentration of the target substance in the target liquid on the basis of the output signal from the concentration sensor 35 during a period in which the first flow rate adjustment device 36 is controlling the flow rate of a filtered dialysate to be equal to or less than the flow rate of the unpurified target liquid.

Description

Target liquid purification equipment

[0001] The present invention relates to a device for purifying a target liquid.

[0002] Conventionally, from the viewpoint of reducing the total amount of dialysate used in dialysis methods, blood purification methods involving partial regeneration using an adsorbent have been proposed (see, for example, Patent Document 1).

[0003] U.S. Patent No. 9,302,038

[0004] However, the dialysis method disclosed in Patent Document 1 has the problem that the total amount of dialysis is still large because a substitution fluid is supplied during dialysis. Also, a large amount of substitution fluid is required. In other words, the dialysis method disclosed in Patent Document 1 is insufficient from the viewpoint of reducing the total amount of dialysis fluid.

[0005] Furthermore, reducing the total volume of dialysis fluid generally poses a problem of insufficient dialysis. From the perspective of reducing the total volume of dialysis fluid, it is conceivable to measure the concentration of a target substance in the target fluid (blood) during purification (during dialysis) in order to determine whether dialysis has been performed sufficiently. One method involves directly inserting a measuring device that measures the target substance into the human body. However, inserting a measuring device into the human body complicates the device or dialysis method from a safety standpoint, posing problems in terms of safety and efficiency.

[0006] Another possible method is to collect blood during dialysis without using a measuring device. However, this method requires blood to be collected during dialysis through a separate fluid passageway that is separate from the fluid passageway connecting to the dialysis machine. This complicates the device or dialysis method from a safety standpoint, posing safety and efficiency challenges.

[0007] Another possible method is to install a measuring device inside the dialysis machine. However, this method has the problem that the blood only comes into contact with the porous membrane for a short period of time during dialysis, resulting in a difference in concentration before and after passing through the porous membrane, making it impossible to accurately measure the concentration of the target substance in the blood.

[0008] Therefore, the present invention aims to provide a target fluid purification device that can reliably perform dialysis, reduce the total amount of dialysis fluid used in dialysis, and accurately measure the concentration of a target substance in blood without sampling blood, while having a simple structure that is safe enough not to affect the human body.

[0009] In order to achieve the above object, the liquid purification device has the following invention-specific features.

[0010] a target fluid purification device for removing at least one target substance from an unpurified target fluid, the target fluid purification device comprising: a porous membrane having a pore size that allows the target substance contained in the unpurified target fluid to pass through; and a first portion and a second portion separated by the porous membrane, a separation device that generates a dialysis fluid by passing the unpurified target fluid containing the target substance from the first portion through the porous membrane and introducing it into the second portion, and generates a purified target fluid by removing the target substance contained in the unpurified target fluid through this passage; an unpurified target fluid passage for introducing the unpurified target fluid into the first portion of the separation device; a purified target fluid passage for leading the purified target fluid from the first portion of the separation device; a dialysis fluid passage for leading the dialysis fluid from an outlet of the second portion of the separation device; a drainage passage for discarding the dialysis fluid from the dialysis fluid passage as drainage; and a dialysis fluid passage for leading the dialysis fluid to an inlet provided upstream of the outlet of the second portion. The device comprises a concentration sensor provided in at least one of the dialysis fluid passage and the drainage passage, and outputting a signal corresponding to the concentration of the target substance in the dialysis fluid; a flow rate adjustment device provided in at least one of the dialysis fluid passage and the drainage passage, and adjusting the flow rate of the dialysis fluid; and a concentration measurement device that measures the concentration of the target substance based on the output signal of the concentration sensor during a period when the flow rate adjustment device controls the flow rate of the dialysis fluid to be equal to or lower than the flow rate of the unpurified target fluid.

[0011] The target fluid purification device having the above-described configuration preferably further comprises a replenishment fluid passage for introducing a replenishment fluid into the target fluid purification device, and the replenishment fluid passage is configured to introduce the replenishment fluid into at least one of the unpurified target fluid passage, the purified target fluid passage, and the dialysis fluid passage.

[0012] In the target fluid purification device having any of the above configurations, it is preferable that the drainage passage is configured to branch off from the filtrate dialysate passage and to discard a first liquid that is a part of the filtrate dialysate as drainage, and that the filtrate dialysate passage is configured to introduce a second liquid that is the remainder of the filtrate dialysate into an inlet part of the dialysis fluid passage as dialysis fluid.

[0013] In any of the above-described target fluid purification devices, it is preferable that the device further comprises a replenishment fluid passage for introducing a replenishment fluid into the target fluid purification device, and that the replenishment fluid passage is configured to introduce the replenishment fluid into at least one of the unpurified target fluid passage, the purified target fluid passage, the filtered dialysis fluid passage, and the dialysis fluid passage.

[0014] In the target fluid purification device having any of the above configurations, it is preferable that the device further comprises a regeneration unit that is provided in the filtered dialysate passage between a branch point of the discharge passage and an inlet of the dialysate passage, the regeneration unit having an adsorbent that adsorbs the target substances, and that removes at least one of the target substances from the second liquid by bringing the second liquid introduced from the filtered dialysate passage into contact with the adsorbent, thereby producing a regenerated liquid having a reduced concentration of the target substances, and that the regeneration unit is configured to introduce the regenerated liquid into the inlet of the dialysate passage as the dialysate.

[0015] In any of the above-described target fluid purification devices, it is preferable that the device further comprises a replenishment fluid passage for introducing a replenishment fluid into the target fluid purification device, and that the replenishment fluid passage is configured to introduce the replenishment fluid into at least one of the unpurified target fluid passage, the purified target fluid passage, the filtered dialysis fluid passage, and the dialysis fluid passage.

[0016] In any of the above-described target liquid purification devices, it is preferable that the target liquid purification device further comprises a waste liquid flow rate adjusting device that adjusts the flow rate of the first liquid, and a replenisher liquid flow rate adjusting device that adjusts the flow rate of the replenisher liquid.

[0017] In any of the target liquid purification devices having the configuration described above, it is preferable to include an abnormality detection device that detects abnormalities based on time-series fluctuations in the concentration of the target substance, and an alarm device that notifies of abnormalities detected by the abnormality detection device.

[0018] In the subject fluid purification device having any of the above configurations, the concentration sensor and the flow rate regulator are provided in at least one of the dialysate passage and the drain passage, so that the degree of purification of the subject fluid can be estimated without separately sampling blood.

[0019] The concentration measuring device measures the concentration of the target substance based on the output signal of the concentration sensor during the period when the flow rate adjusting device controls the flow rate of the dialysis fluid to be equal to or lower than the flow rate of the unpurified target fluid. Therefore, when the concentration measuring device measures the concentration of the target substance in the target fluid (e.g., blood), the unpurified target fluid is in contact with the porous membrane for a long period of time. This results in the concentration of the target substance in the unpurified target fluid being approximately the same as the concentration of the target substance in the dialysis fluid. Therefore, the concentration of the target substance in the unpurified target fluid can be measured efficiently, safely, and accurately without having to separately collect blood or insert a concentration measuring device into the human body.

[0020] FIG. 1 is a diagram illustrating the configuration of a target liquid purification device. FIG. 2 is a diagram illustrating the configuration of a main body of a target liquid purification device according to a first embodiment. FIG. 3 is a diagram illustrating the configuration of a main body of a target liquid purification device according to a second embodiment. FIG. 4 is a diagram illustrating the configuration of a main body of a target liquid purification device according to a fourth embodiment. FIG. 5 is a diagram illustrating the concentration of urea nitrogen in the unpurified target liquid and the concentration of the first liquid for each flow rate of replenishment liquid in the target liquid purification device according to the example. Ｄ (replenishment fluid flow rate) and C ＤＯ1 is a diagram showing the relationship between the urea nitrogen concentration and the position of the separation device as seen from the unpurified target liquid passage when the flow rate of the replenisher liquid is 500 mL / min in the target liquid purification device of the embodiment. FIG. 2 is a diagram showing the relationship between the urea nitrogen concentration and the position of the separation device as seen from the unpurified target liquid passage when the flow rate of the replenisher liquid is 230 mL / min in the target liquid purification device of the embodiment. FIG. 3 is a diagram showing the relationship between the urea nitrogen concentration and the position of the separation device as seen from the unpurified target liquid passage when the flow rate of the replenisher liquid is 150 mL / min in the target liquid purification device of the embodiment.

[0021] (First Embodiment) The target fluid purification device according to the first embodiment shown in Fig. 1 includes a main body 1, a concentration measuring device 2, a control device 3, and an alarm device 4. Fig. 2 is a schematic diagram of the main body 1 shown in Fig. 1 according to the first embodiment. As shown in Fig. 2, the main body 1 includes a separation device 100, an unpurified target fluid passage 11, a purified target fluid passage 12, a filtered dialysate passage 21, a dialysate passage 412, a drainage passage 24, a first flow rate adjustment device 36, and a concentration sensor 35 that outputs a signal corresponding to the concentration of a target substance in the target fluid. The concentration measuring device 2 measures the concentration of the target substance in the target fluid based on the output signal of the concentration sensor 35.

[0022] The separation device 100 is separated into a first portion 110 and a second portion 120 by a porous membrane 102. The porous membrane 102 has a pore size that allows target substances contained in the unpurified target fluid F11 (e.g., blood, plasma, dialysis effluent, hemofiltrate) to pass through. The "target substance" refers to a pathogenic substance that accumulates in the body during illness, such as at least one ion selected from potassium ions, ammonium ions, calcium ions, magnesium ions, phosphate ions, bicarbonate ions, and organic acid ions, urea, creatinine, uric acid, peptides, and proteins. The separation device 100 generates a dialysis filtrate F21 by passing the unpurified target fluid F11 containing the target substance from the first portion 110 through the porous membrane 102 and introducing it into the second portion 120. The separation device 100 is configured to generate a purified target fluid F12 by removing the target substances contained in the unpurified target fluid F11 through this passage. It should be noted that the fluid moving from the first portion 110 to the second portion 120 here is the water removing fluid F0.

[0023] Here, the "dehydration fluid" refers to excess water contained in the body. This water is preferably excreted during the purification of the target fluid. The amount of dehydration fluid F0 typically varies from person to person and is calculated using a predetermined calculation method based on the user's weight, meal frequency, height, etc. For a normal person (e.g., a person weighing 60 kg or less), it is preferable to keep the flow rate of dehydration fluid F0 within 1000 mL per hour.

[0024] The unpurified liquid passage 11 is configured to introduce the unpurified liquid F11 drawn from the patient's body into the first section 110 of the separation device 100. The purification target liquid passage 12 is configured to introduce the purification target liquid F12 from the first section 110 of the separation device 100 and into the patient's body. The separation device 100 is configured, for example, by a dialyzer. The first section 110 is the internal space of hollow fibers formed by dialysis membranes. As will be described later, the second section 120 is the space around the hollow fibers through which dialysis fluid and / or regenerated fluid flows.

[0025] In this embodiment, the separation device 100 is configured as a "countercurrent separation device" in which the flow direction of the unpurified liquid F1 in the first portion 110 and the flow direction of the regenerated liquid F22 in the second portion 120 are opposite or opposite to each other. On the other hand, in other embodiments, the separation device 100 may be configured as a "parallel current separation device" in which the flow direction of the unpurified liquid F11 in the first portion 110 and the flow direction of the regenerated liquid F22 in the second portion 120 are parallel or in the same direction.

[0026] The dialysate filtrate passage 21 allows the dialysate filtrate F21 to be discharged from the second portion 120 of the separation device 100. The drain passage 24 allows the dialysate filtrate F21 introduced from the dialysate filtrate passage 21 to be discarded as drainage F41.

[0027] The dialysate passage 412 is configured to directly introduce the dialysate F41 into an introduction port provided upstream of the outlet port of the second section 120. Here, the "dialysate" means, for example, fresh dialysate.

[0028] The first flow rate control device 36 is, for example, a flow rate control valve, a pump, or a mass flow controller, and is provided in at least one of the dialysate passage 21 and the drainage passage 24. The first flow rate control device 36 adjusts the flow rate of the dialysate F21. In particular, the first flow rate control device 36 is provided to control the flow rate of the dialysate F21 to be equal to or lower than the flow rate of the unpurified target fluid F11.

[0029] The concentration sensor 35 outputs a signal corresponding to the concentration of the target substance in the target fluid and is provided in at least one of the dialysate passage 21 and the drain passage 24. Different types of concentration sensors 35 may be provided to measure the respective concentrations of multiple target substances. By providing the concentration sensor 35 in the passage through which the dialysate F21 passes, the concentration of the target substance in the unpurified target fluid F11 can be estimated without providing a concentration sensor 35 inside the human body. Furthermore, as will be described later in the results section, the concentration sensor 35 measures the concentration of the target substance while the first flow control device 36 controls the flow rate of the dialysate F21 to be equal to or lower than the flow rate of the unpurified target fluid F11. Therefore, the concentration of the target substance present in the dialysate F21 or the drain F211 can be referred to as the concentration of the target substance in the unpurified target fluid F11. Since the composition of the unpurified target fluid can be determined based on the results measured by the concentration sensor 35, the target fluid purification device can adjust the flow rate of each fluid in the target fluid purification device based on the concentration of the target substance. Furthermore, the degree of purification can be quantified, and purification of the target fluid can be terminated at an appropriate timing. For these reasons, purification of the target fluid is possible without adding more dialysate or substitution fluid than necessary.

[0030] The concentration sensor 35 is preferably provided downstream of the first flow rate control device 36, but may be provided upstream of the first flow rate control device 36. In addition, both the concentration sensor 35 and the first flow rate control device 36 may be provided in either the dialysate passage 21 or the drainage passage 24, or each may be provided in a different location.

[0031] Typically, during purification of the target fluid, it is difficult to achieve uniformity in the flow of the dialysate, so the flow rate of the dialysate F412 is set to about twice the flow rate of the unpurified target fluid F11. On the other hand, when the concentration measuring device 2 measures the concentration of the target substance, the flow rate of the dialysate F412 is set to the same as or lower than the flow rate of the unpurified target fluid F11. In this case, since the unpurified target fluid F11 is in contact with the porous membrane 102 for a long time, the concentration of the unpurified target fluid F11 is approximately the same as the concentration of the dialysis fluid F21. Furthermore, since the flow rate of the dialysis fluid F21 is set higher than that of the replacement fluid F41, water can be removed from the unpurified target fluid F11 by the amount corresponding to the amount of water removed, and the flow rate of the water removal fluid F0 can also be controlled.

[0032] In this embodiment, the flow rate of the dialysate F412 is approximately equal to the sum of the flow rates of the dialysis fluid F21 and the dewatering fluid F0. Since the dialysis fluid F21 and the regeneration fluid F22 flow through a constant-volume flow path, when the flow rate of the dialysate F412, the flow rate of the dialysis fluid F21, and the flow rate of the dewatering fluid F0 are approximately equal, the sum of the flow rates of the unpurified target fluid F11 and the purified target fluid F12 and the flow rate of the dewatering fluid F0 is equal to the difference in flow rate between the dialysis fluid F41 and the dialysis fluid F21.

[0033] In this embodiment, the target liquid purification apparatus includes, in addition to the main body 1 described above, a concentration measuring device 2, a control device 3, and an alarm device 4, as shown in FIG. 1 . The concentration measuring device 2 and the control device 3 are configured with a storage device (such as RAM, ROM, EEPROM, SSD, HDD, etc.) that stores and retains programs (software) and data, a processing device (such as a single-core processor, multi-core processor, or CPU) that reads necessary programs and / or data from the storage device and executes predetermined arithmetic processing, and I / O circuits. As described below, the concentration measuring device 2 and the control device 3 measure the concentration of the target substance based on the signal output by the concentration sensor 35 while controlling the flow rate adjusted by the first flow rate adjustment device 36, and control the entire target liquid purification apparatus. The control device 3 is provided with an abnormality detection device 301, which detects an abnormality based on the concentration of the target substance measured by the measurement device, as described below.

[0034] The notification device 4 includes an output interface 402. The notification device 4 may be an audio output device, an image output device, a personal computer, a mobile phone (smartphone), or any other information terminal device. The notification device 4 is configured to, for example, notify of an abnormality detected by the abnormality detection device 301 and present various information during the purification of the target liquid.

[0035] Second Embodiment Fig. 3 shows a schematic diagram of a second embodiment of the main body 1 in Fig. 1. The second embodiment relates to a subject fluid purification device that further includes a substitution fluid passage 422 for introducing a substitution fluid F42 into the main body 1 of the first embodiment. The substitution fluid passage 422 is configured to introduce the substitution fluid F422 into at least one of the unpurified subject fluid passage 11, the purification subject fluid passage 12, and the dialysate passage 412. The remaining configuration is substantially the same as in the first embodiment, and therefore a description of the overlapping parts will be omitted.

[0036] The replenishment fluid passage 422 may be provided in any one of the above-described passages, or may be provided simultaneously in multiple passages. For example, the replenishment fluid passage 422 may be configured to introduce the replenishment fluid F422 into both the unpurified target fluid passage 11 and the dialysate passage 412. Furthermore, the replenishment fluid passage 422 is preferably configured to introduce the replenishment fluid F422 downstream of the position where the concentration sensor 35 is provided. In this case, when the concentration measurement device 2 measures the concentration of the target substance, the unpurified target fluid F11 contacts the porous membrane 102 for a long period of time, thereby enabling accurate measurement of the concentration of the target substance in the filtered dialysis fluid F21. In addition, without being limited to the above embodiment, the replenishment fluid passage 422 may be configured to introduce the replenishment fluid F422 downstream of the position where the concentration sensor 35 is provided. In this case, the flow rate of the replenishment fluid is adjusted by the third flow rate adjustment device 32 described below. Furthermore, when the concentration measurement device 2 measures the concentration based on the signal from the concentration sensor 35, the flow rate of the replenishment fluid can be adjusted to allow the unpurified target fluid F11 to contact the porous membrane 102 for a long period of time. In addition, by recognizing the flow rate of the filtrate dialysis fluid F21 and the flow rate of the replacement fluid F422 and applying an appropriate correction coefficient based on the ratio of these flow rates, the concentration of the target substance in the unpurified target fluid F422 can be accurately measured.

[0037] The main body 1 may further include a second flow control device 31 that adjusts the flow rate of the first fluid F211 discharged from the target fluid purification device, and a third flow control device 32 that adjusts the flow rate of the replacement fluid F42 introduced into the replacement fluid passage 422. The second flow control device 31 is, for example, a flow control valve or a mass flow controller, and is provided in the drainage passage 24. The third flow control device 32 is, for example, a flow control valve or a mass flow controller, and is provided in the replacement fluid passage 422 or the dialysate passage 412.

[0038] As described below, the second flow control device 31 and the third flow control device 32 may be controlled by the control device 3 to adjust their respective flow rates in accordance with the concentration of the target substance measured by the concentration sensor 35. In this case, the control device 3 may control each of the second flow control device 31 and the third flow control device 32 to reduce the deviation between the amount of replacement fluid F41 introduced and the amount of the first fluid F211 discharged, or to reduce the deviation between the total amount of replacement fluid F41 introduced and the amount of water removed and the amount of water removed from the first fluid F212. When controlled in this manner, the unpurified target fluid F11 is in contact with the porous membrane 102 for a long period of time, so that the concentration of the target substance in the unpurified target fluid F11 and the concentration of the target substance in the dialysis filtration fluid F21 are approximately equal. Furthermore, by increasing the flow rate of the dialysis filtration fluid F21 relative to the flow rate of the replacement fluid F41, water can be removed from the unpurified target fluid F11, thereby controlling the flow rate of the water remover F0.

[0039] Third Embodiment Fig. 4 is a schematic diagram of the main body 1 in Fig. 1 according to a third embodiment. The third embodiment relates to a subject fluid purification device further including a branching section at the downstream end of the dialysis fluid passage 21 that branches the dialysis fluid F21 into a first fluid F211 and a second fluid F212. The drainage passage 24 branches from the dialysis fluid passage 21 and discards the first fluid F211, which is a portion of the dialysis fluid F21, as drainage. The dialysis fluid passage 21 is also configured to introduce the second fluid F212, which is the remainder of the dialysis fluid F21, into an inlet of the dialysis fluid passage 412 as the dialysis fluid F41. That is, the third embodiment relates to a circulating subject fluid purification device.

[0040] Furthermore, as in the second embodiment, the main body 1 of the third embodiment may further include a replacement fluid passage 422 that introduces the replacement fluid F42 into the main body 1. Here, the replacement fluid passage 422 is configured to introduce the replacement fluid F422 into at least one of the unpurified liquid passage 11, the purified liquid passage 12, and the dialysate passage 412. The other configurations are substantially the same as those of the first or second embodiment, and therefore, a description of the overlapping parts will be omitted.

[0041] Fourth Embodiment FIG. 5 shows a schematic diagram of the main body 1 shown in FIG. 1 according to a fourth embodiment. The fourth embodiment relates to a target fluid purification device further including a regeneration unit 200 disposed between the branch point of the dialysis fluid passage 21 from the drain passage 24 and the inlet of the dialysate passage 412. The regeneration unit 200 includes an adsorbent that adsorbs target substances. The regeneration unit 200 removes at least one target substance from the second fluid F212 by contacting the adsorbent with the second fluid F212 introduced from the dialysis fluid passage 21, thereby producing a regenerated fluid F22 having a reduced concentration of the target substance. The regeneration unit 200 is configured to introduce the regenerated fluid F22 into the inlet of the dialysate passage 412 as the dialysate F41. Other configurations are substantially similar to those of the third embodiment, and therefore, a description of the overlapping portions will be omitted.

[0042] (Configuration of the Regeneration Unit) The regeneration unit 200 has an adsorbent that adsorbs the target substance. The adsorbent may be activated carbon and / or an adsorbent based on activated carbon, a porous adsorbent, a cation exchange resin, an anion exchange resin, a zirconia-based ceramic, a zeolite, or a mixture thereof. The regeneration unit 200 is configured to remove at least a portion of the target substance by contacting a portion of the dialysis fluid (the second fluid F212) with the adsorbent, thereby generating a regenerated fluid F22 in which the concentration of the target substance has been reduced.

[0043] In the fourth embodiment, the second fluid F212 is configured to be introduced into the regeneration unit 200. The drainage passage 24 branches off from the filtrate passage 21 and is configured to discard the first fluid F211 as a drainage fluid out of the first fluid F211 and the second fluid F212 resulting from separation of the filtrate F21. The flow rate of the drainage fluid in the drainage passage 24 (the discarded amount of filtrate F21) may be appropriately controlled based on the inflow rate of the substitution fluid (fresh dialysis fluid) into the regeneration fluid passage 22 and / or the outflow rate of the regeneration fluid F22 from the regeneration fluid passage 22, taking into account the flow rate of the regeneration fluid F22 in the second part 120 of the separation device 100. The regeneration fluid passage 22 is configured to introduce the regeneration fluid F22 from the regeneration unit 200 into the second part 120 of the separation device 100.

[0044] In this embodiment, the reproducing unit 200 is preferably configured with at least one reproducing circuit. When there are two or more reproducing circuits, the reproducing circuits are preferably connected in series with each other, but this is not a limitation and they may be connected in parallel.

[0045] Although the second to fourth embodiments have been described as modifications of the first embodiment, the configurations of the respective embodiments may be combined. For example, the configuration of the second embodiment may be combined with the fourth embodiment.

[0046] (Concentration Measurement Method) Next, a method for measuring the concentration of a target substance in a target liquid in a target liquid purification method executed by the target liquid purification device, which is common to the first to fourth embodiments, will be described.

[0047] The concentration of the target substance is measured, for example, when a request signal is received via the input interface of the target liquid purification device so that a medical professional or the patient can determine whether the target liquid has been sufficiently purified. Furthermore, the concentration of the target substance is automatically measured when the purification of the target liquid begins or when a specified time has elapsed since the previous concentration measurement, for example, when the aperture of the fourth flow control device 2013 is adjusted according to the concentration of the target substance, as in the fourth embodiment.

[0048] When measuring the concentration of a target substance, the output of the first flow control device 36 is set to make the flow rate of the dialysis fluid F21 equal to or less than the flow rate of the unpurified target fluid F11. This prevents the unpurified target fluid F11 from contacting the porous membrane 102 more than necessary, so the concentration of the unpurified target fluid F11 and the concentration of the dialysis fluid F21 are approximately the same. Furthermore, since water can be removed from the unpurified target fluid F11 by the amount that the flow rate of the dialysis fluid F21 is made higher than the flow rate of the replacement fluid F41, the flow rate of the dewatering fluid F0 can also be controlled.

[0049] When the first flow control device 36 reduces the flow rate of the filtered dialysis fluid F21 to the same as or less than the flow rate of the unpurified target fluid F11, the concentration measuring device 2 measures the concentration of the target substance in the target fluid based on the output signal of the concentration sensor 35.

[0050] The concentration of the target substance may be recorded or output to an alarm device at the same time as the measurement, allowing medical personnel and patients to easily grasp the concentration of the target substance during purification of the target liquid and quantitatively determine the degree of purification of the target liquid.

[0051] In addition, when the replenishment fluid passage 422 is configured to introduce the replenishment fluid F422 downstream of the position where the concentration sensor 35 is provided, the concentration measuring device 2 may be configured to accurately measure the concentration of the target substance in the unpurified target fluid F422 by multiplying the concentration of the target substance by an appropriate correction coefficient based on the flow rate ratio between the flow rate of the filtered dialysis fluid F21 and the flow rate of the replenishment fluid F422.

[0052] (Abnormality detection method) In addition to the configuration of the above embodiment, the target liquid purification device is equipped with an abnormality detection device 301 that detects abnormalities based on time-series fluctuations in the concentration of the target substance, and an alarm device 4 that alarms abnormalities detected by the abnormality detection device 301.

[0053] The anomaly detection device 301 constitutes part of the control device 3 and is a device that detects anomalies based on the time series of the concentration of a target substance. Here, the time series fluctuation of the concentration of a target substance refers to, for example, information representing the concentration measured by the concentration measuring device 2 over time. In this case, the values ​​of multiple target substances may be used as the concentration values. Based on the time series information of the concentrations of the multiple target substances, an abnormal value is calculated statistically or using a machine learning method. For example, if the concentration values ​​do not fluctuate, it can be determined that dialysis is not being performed sufficiently. Furthermore, if the concentration of a specific substance is higher than that of other substances, it can be determined that the composition of the replacement fluid and / or dialysis fluid is insufficient.

[0054] The notification device 4 is connected to the target liquid purification device via wireless communication such as a network or wired communication such as a cable. The notification device 4 is, for example, software installed on a personal computer, smartphone, etc. The notification device 4 is carried by, for example, a patient using the target liquid purification device, their family, or a medical professional in charge.

[0055] If the abnormality detection device 301 detects an abnormality, the output interface 402 of the alarm device 4 will be notified of this. This allows the user to recognize the deterioration of the target liquid purification device and / or the target liquid purification process, etc., and based on this recognition, can reliably perform target liquid purification. Furthermore, since medical professionals can recognize in advance the presence or absence of disease or the risk of disease, they can beneficially perform target liquid purification to maintain the health of patients using the target liquid purification device.

[0056] Example 1 is a subject fluid purification device having the configuration of the first embodiment. Figure 6 is a graph showing the concentration of urea nitrogen, a subject substance, in the unpurified subject fluid F11 and the first fluid F211 (the same as the filtered dialysis fluid F21) when the flow rate of the dialysate F41 in the subject fluid purification device of Example 1 was set to 100, 200, 300, and 450 mL / min. Note that the unpurified subject fluid F11 (blood flow rate) was 250 mL / min. Referring to Figure 6, when the flow rate of the dialysate F41 was higher than the flow rate of the unpurified subject fluid F11 (substitution fluid F41 flow rate: 100 or 200 mL / min), the urea nitrogen concentration in the unpurified subject fluid F11 and the urea nitrogen concentration in the first fluid F211 were approximately the same. On the other hand, when the flow rate of the dialysis fluid F41 was greater than the flow rate of the unpurified target fluid F11 (dialysis fluid F41 flow rate: 300, 450 mL / min), the urea nitrogen concentration of the first fluid F211 was lower than the urea nitrogen concentration in the unpurified target fluid F11.

[0057] Here, the removal performance when passing through the target liquid purification device once is expressed as an index called clearance CL. The clearance CL is calculated by multiplying the urea nitrogen concentration C ＢＩ , urea nitrogen concentration C in the purification target liquid F12 ＢＯ , the flow rate Q of the unpurified target liquid F11 ＢUsing the above, the following relational expression (1) is obtained.

[0058] CL = ((C BI -C ＢＯ ) / C ＢＩ ) *Q Ｂ　　　 ...(1)

[0059] Here, Q Ｂ When the flow rate is 250 mL / min, a CL of 230 to 250 mL / min means that approximately 100% of the urea nitrogen is removed during a single pass through the target fluid purification device. In addition, the concentration of urea nitrogen in the first fluid F211 at this time can be calculated from the mass balance by dividing the concentration of urea nitrogen in the dialysate F41, the concentration of urea nitrogen in the first fluid F211, and the flow rate of the dialysate F41 by C. ＤＩ , C ＤＯ , Q Ｄ and is expressed by the following relational expression (2).

[0060] Q Ｂ *(C ＢＩ -C ＢＯ ) = Q Ｄ *(C ＤＯ -C ＤＩ ) (2)

[0061] Furthermore, when the overall mass transfer area coefficient KoA is used, the following relational expression (3) is obtained.

[0062] (C ＢＩ -C ＢＯ ) / (C ＢＩ -C ＤＩ ) = (1-exp(KoA(1 / Q ＢＩ -1 / Q ＢＯ ))) / (Q ＢＩ / Q ＤＩ -exp(KoA(1 / Q ＢＩ -1 / Q ＢＯ ))) ...(3)

[0063] Based on the above relations (1) to (3), C ＤＯ At this time, the operating conditions are Ｂ =200mL / min, C ＢＩ= 100 mg / dL, the KoA for urea nitrogen can be considered to be about 3000. The length of the separation device (dialyzer) is 25 cm, and the membrane area is 1.5 m ２ Then, Q Ｄ When C is changed ＤＯ is calculated, and FIG. 7 is obtained.

[0064] 7, when the flow rate of the dialysate F41 is less than 200 mL / min, which is approximately the same as the flow rate of the unpurified target fluid F11, the first fluid F211 has a concentration of 100 mg / dL, which is approximately the same as the unpurified target fluid F11. This is because the urea nitrogen moves from the unpurified target fluid F11 to the separation device in the target fluid purification device at a very high speed. In this case, the concentration distribution of urea nitrogen on the unpurified target fluid F11 side and the dialysate F41 side in the target fluid purification device can be calculated as shown in FIG.

[0065] In Figure 8, the horizontal axis represents the longitudinal position of the separation device 100 (the inflow portion of the unpurified target fluid F11 into the separation device is indicated by 0, and the outflow portion of the purified target fluid F12 is indicated by 25), and the vertical axis represents the urea nitrogen concentration. Here, the solid line represents the urea nitrogen concentration on the first portion 110 side, and the dotted line represents the urea nitrogen concentration on the second portion 120 side. Referring to Figure 8A, when the flow rate of the replacement fluid F41 is 500 mL / min, it can be considered that the urea nitrogen in the unpurified target fluid F11 is substantially 100% removed (the urea nitrogen value at 25 cm is substantially 0). Referring to Figure 8B, when the flow rate of the dialysate F41 is 230 mL / min, the urea nitrogen is also substantially 100% removed. In this case, the value of the y-intercept, which represents the urea nitrogen concentration of the first fluid F211, is 40 mg / dL when the flow rate of the dialysate F41 is 500 mL / min, which is lower than the urea nitrogen concentration of the unpurified target fluid F11. Meanwhile, as the flow rate of the dialysate F41 decreases, the urea nitrogen concentration of the first fluid F211 increases. Referring to FIG. 8C , in the graph where the flow rate of the dialysate F41 is 150 mL / min, the urea nitrogen concentrations of the unpurified target fluid F11 and the first fluid F211 are approximately 100 mg / dL and can be considered equivalent. This allows the urea nitrogen concentration of the unpurified target fluid F11 to be determined by measuring the urea nitrogen concentration of the first fluid F211 or the dialysis fluid F21, without the need to provide a concentration sensor 35 in the unpurified target fluid F11 (blood). As a result, the above-mentioned process is carried out, so that the total amount of dialysate F41 in the subject fluid purification device can be reduced and purification can be reliably carried out.

[0066] Although the results were shown using the values ​​of urea nitrogen in the examples, similar results were observed for substances other than urea nitrogen that had high permeability to the separation membrane. Although not specifically shown, similar results were also observed in an example using potassium ions. Therefore, such a target liquid purification device can accurately measure the concentrations of multiple target substances, enabling overall control of the target liquid purification device based on the concentrations.

[0067] As described above, the target fluid purification device can reduce the amount of dialysis fluid and perform control to reliably remove target substances from the target fluid. Therefore, it can be used for home dialysis, etc. Furthermore, if an abnormality occurs during home dialysis, the abnormality can be communicated to a remote medical professional, etc., thereby providing reliable dialysis treatment. Furthermore, it is possible to provide a target fluid purification device that can reliably perform dialysis, reduce the total amount of dialysis fluid used in dialysis, and accurately measure the concentration of target substances in blood without sampling blood, while having a simple and safe structure that does not affect the human body.

[0068] It should be noted that the present invention is not limited to the above-described embodiments or examples, and it is clear that the scope of the present invention can be modified or altered within a range that is obvious to those skilled in the art. It is also clear that the scope of the present invention is not limited to the above-described embodiments or examples, but also includes modifications and alterations thereof.

[0069] 1. Main body 2. Concentration measuring device 3. Control device 4. Notification device 11. Unpurified target fluid passage 12. Purified target fluid passage 21. Filtration dialysis fluid passage 22. Regenerated fluid passage 24. Drainage fluid passage 31. Second flow rate adjustment device 32. Third flow rate adjustment device 35. Concentration sensor 36. First flow rate adjustment device 100. Separation device 102. Porous membrane 110. First part 120. Second part 200. Regeneration section 201. Regeneration circuit 202. Regeneration circuit 221. Regenerated fluid branch passage 222. Regenerated fluid branch passage 301. Abnormality detection device 401. Input interface 402. Output interface 412. Dialysis fluid passage 422. Substitute fluid passage 2011. First circuit (regeneration circuit 201) 2012. Second circuit (regeneration circuit 201) 2013: Fourth flow rate adjustment device (regeneration circuit 201) 2021: First circuit (regeneration circuit 202) 2022: Second circuit (regeneration circuit 202) 2023: Fourth flow rate adjustment device (regeneration circuit 202) F11: Unpurified target fluid F12: Fluid to be purified F21: Filtered dialysis fluid F211: First fluid (discharge fluid) F212: Second fluid F22: Regenerated fluid F41: Dialysis fluid F42: Replacement fluid.

Claims

1. A target fluid purification device for removing at least one target substance from an unpurified target fluid, comprising: a porous membrane having a pore size that allows the target substance contained in the unpurified target fluid to pass through; and a first portion and a second portion separated by the porous membrane, a separation device that generates a dialysis fluid by passing the unpurified target fluid containing the target substance from the first portion through the porous membrane and introducing it into the second portion, and removes the target substance contained in the unpurified target fluid by this passage, thereby generating a purified target fluid; an unpurified target fluid passage for introducing the unpurified target fluid into the first portion of the separation device; a purified target fluid passage for leading the purified target fluid from the first portion of the separation device; a dialysis fluid passage for leading the dialysis fluid from an outlet of the second portion of the separation device; a drainage passage for discarding the dialysis fluid from the dialysis fluid passage as effluent; and a dialysis fluid passage for leading the dialysis fluid to an inlet provided upstream of the outlet of the second portion. a concentration sensor provided in at least one of the dialysis fluid passage and the drainage passage, for outputting a signal corresponding to the concentration of the target substance in the dialysis fluid; a flow rate adjustment device provided in at least one of the dialysis fluid passage and the drainage passage, for adjusting the flow rate of the dialysis fluid; and a concentration measurement device for measuring the concentration of the target substance based on the output signal of the concentration sensor during a period in which the flow rate adjustment device controls the flow rate of the dialysis fluid to be equal to or lower than the flow rate of the unpurified target fluid.

2. A target fluid purification device according to claim 1, further comprising a replacement fluid passageway for introducing replacement fluid into said target fluid purification device, said replacement fluid passageway being configured to introduce said replacement fluid into at least one of said unpurified target fluid passageway, said purified target fluid passageway and said dialysate passageway.

3. A subject fluid purification device according to claim 1, wherein the drainage passage is configured to branch off from the filtered dialysate passage and to discard a first liquid, which is a part of the filtered dialysate, as drainage, and the filtered dialysate passage is configured to introduce a second liquid, which is the remainder of the filtered dialysate, into an inlet of the dialysate passage as dialysate.

4. A target fluid purification device according to claim 3, further comprising a replenishment fluid passage for introducing a replenishment fluid into said target fluid purification device, said replenishment fluid passage being configured to introduce said replenishment fluid into at least one of said unpurified target fluid passage, said purified target fluid passage, said filtered dialysis fluid passage and said dialysis fluid passage.

5. A target fluid purification device according to claim 3, further comprising a regeneration unit provided in the filtered dialysate passage between the branch point of the discharge passage and the inlet of the dialysate passage, the regeneration unit having an adsorbent that adsorbs the target substances, and which removes at least one of the target substances from the second liquid by bringing the second liquid introduced from the filtered dialysate passage into contact with the adsorbent, thereby producing a regenerated liquid having a reduced concentration of the target substances, and the regeneration unit is configured to introduce the regenerated liquid into the inlet of the dialysate passage as the dialysate.

6. A target fluid purification device according to claim 5, further comprising a replacement fluid passageway for introducing replacement fluid into said target fluid purification device, said replacement fluid passageway being configured to introduce said replacement fluid into at least one of said unpurified target fluid passageway, said purified target fluid passageway, said filtered dialysate passageway and said dialysate passageway.

7. A target liquid purification device according to claim 6, comprising a waste liquid flow rate adjusting device for adjusting the flow rate of the first liquid, and a replenisher liquid flow rate adjusting device for adjusting the flow rate of the replenisher liquid.

8. A target liquid purification device according to any one of claims 1 to 7, characterized in that it comprises an abnormality detection device that detects abnormalities based on time-series fluctuations in the concentration of the target substance, and an alarm device that notifies of abnormalities detected by the abnormality detection device.

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