JP2012125449A - Apparatus for producing dilution water for making dialysate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To carry out hot water washing of an apparatus for producing dilution water for making dialysate, in a comparatively short time to maintain the apparatus at high cleanliness for a long period of time.SOLUTION: The apparatus includes a raw water storage tank 3, a pretreatment means 5 containing activated carbon, an RO membrane module 8, a purified water storage tank 9, etc., arranged in this order. An EDI 15 is installed to separate permeated water from the RO membrane module 8 into desalted water, electrode water and concentrated water. The apparatus further includes a desalted water supply passage 24 for supplying desalted water from the EDI to the purified water storage tank 9; circulating lines 12, 13, 21, 22, 23 for returning the permeated water and concentrated water from the RO film module 8 and the desalted water, electrode water and concentrated water from the EDI 15 to the raw water storage tank 3; a heating means 28 provided at the raw water storage tank 3 to heat raw water in the raw water storage tank 3 and circulating water into the raw water storage tank 3 when the RO membrane module 8 and EDI 15 are washed with hot water; and a three-way valve 25 for switching the desalted water supply passage 24 to the desalted water circulating line 21 so that the desalted water in the desalted water supply passage 24 is not supplied to the purified water storage tank 9 during hot water washing.

Description

  The present invention relates to an apparatus for producing dialysate-producing dilution water, which is used to prepare a dialysate for hemodialysis by mixing a powder for dialysis or a concentrated concentrate for dialysis and dilution water at a predetermined ratio.

  In a so-called central dialysis system that allows centralized management of hemodialysis for a large number of people, when preparing dialysate for use in individual hemodialysis, a large amount of stock solution for dialysis is prepared. There are many cases. These dialysis stock solutions are prepared by mixing dialysis powder or dialysis concentrate and dilution water at a predetermined mixing ratio, and dissolving the dialysis powder with dilution water or diluting the dialysis concentrate to a predetermined concentration with dilution water. Is prepared in large quantities. Such a dialysate preparation dilution water usually requires high cleanliness.

  In recent years, the cleanliness requirement for dilution water for preparing dialysate has been further increased. As a device for producing dialysate dilution water, a device equipped with a reverse osmosis membrane module (hereinafter, reverse osmosis is abbreviated as RO) is known. In order to further improve water quality, an RO membrane module is used. It is known to connect two stages in series.

  Furthermore, in the field of pharmaceutical purified water, which has a higher water quality standard than the field of manufacturing dilution water for dialysate preparation, in addition to the RO membrane module, an electric regenerative pure water production device (this device is an electric deionized water production device) (Hereinafter referred to as EDI)) is used (see Patent Document 1). This EDI is basically a desalination chamber in which a gap formed by a cation exchange membrane and an anion exchange membrane is filled with an ion exchanger to form a desalination chamber. A deionized water is produced by applying a direct current through the exchange membrane to electrically exclude impurity ions in the water to be treated into the concentrated water flowing outside the ion exchange membranes. By providing such EDI in the subsequent stage of the RO membrane module, the permeated water of the RO membrane can be further purified.

  In the field of manufacturing dialysate preparation dilution water, a dialysate preparation diluting water manufacturing apparatus in which EDI is added after the RO membrane module is being studied in order to follow the advancement of water quality standards for dilution water (Patent Documents). 2).

JP 2004-74109 A JP 2007-252396 A JP 2010-194092 A

  In the apparatus for producing dialysate preparation dilution water, water used for diluting the dialysate to be put into the human body is produced, and therefore, it is necessary to sterilize the system before starting normal production. In the device for producing purified water for pharmaceuticals disclosed in Patent Document 1, sterilization cleaning with hot water is performed.

  Therefore, also in the apparatus for producing dialysate preparation dilution water using RO membrane module and EDI, sterilization of RO membrane primary and secondary lines, EDI desalted water line, electrode water line and concentrated water line In order to ensure the cleanliness and maintain high cleanliness in the long term, it was considered to carry out sterilization washing with hot water. However, this implementation has the following problems.

  1) In the above hot water cleaning, as shown in Patent Document 1, the raw water tank is provided with heating means for making hot water, and the hot water is sequentially passed through the RO membrane module and the EDI, and the raw water is again supplied. It is conceivable to adopt a circulation system that returns to the tank. However, the apparatus disclosed in Patent Document 1 is a system comprising a raw water tank, an RO membrane module, and EDI in this order, and the water circulated by hot water cleaning is hot water passing through the EDI desalted water line concentrated water line. Only.

  In such a system, the water flowing in the EDI electrode chamber (electrode water) is water near the cathode or anode, and when an EDI voltage is applied (during normal operation), the electrolytic product, ie, the cathode water is hydrogen gas, The anodized water contains an oxidizing gas such as oxygen gas, chlorine gas, ozone gas, and hydrogen peroxide. For this reason, when anodized water containing oxidizing gas is returned to the raw water tank, the performance of the RO membrane in the latter stage (oxidation degradation) may be reduced, or even the RO membrane may permeate into the EDI in some cases. It may cause performance degradation (oxidation degradation). Therefore, a line for discharging these electrode waters to the outside of the system has been provided, and it has been necessary to discharge them outside the system.

  Therefore, the water recovery rate does not become 100% in a system in which the raw water tank, the RO membrane module, and the EDI are provided in this order. In addition, since the same line is used during sterilization washing with hot water (when the EDI voltage is stopped), the electrode water is discharged out of the system, and the hot water returned to the raw water tank is reduced. Hot water supplied to the EDI via the RO membrane module continues to decrease. That is, the utilization efficiency of hot water is low. In order to improve this, an amount equivalent to the amount of electrode water discharged during the cleaning time is added to the raw water tank so that the water in the raw water tank is not exhausted during the hot water cleaning process. It is necessary to keep it. As a result, there arises a problem that the raw water tank is enlarged. Since the dialysate is produced in a hospital facility, not in a pharmaceutical manufacturing factory, a device for manufacturing the dialysate preparation dilution water is required to have a size that can be easily transported and installed in the hospital facility. The problem of increasing the size of the raw water tank cannot meet this requirement. Furthermore, a drainage treatment facility is required along with the discharge line for discharging the electrode water together with the installation of this manufacturing apparatus, and is not suitable as a manufacturing apparatus for diluting water for making dialysate in a hospital facility.

  2) Since it is not preferable to supply hot water to the RO membrane and the EDI ion exchange membrane at once, the temperature rise in the raw water tank gradually increases while circulating between the RO membrane, EDI and the raw water tank. It is desirable to keep warm. However, as described above, the hot water recirculated to the raw water tank is reduced, and the RO membrane and the EDI ion exchange membrane inhibit the temperature rise. It takes time to raise the temperature. In addition, some of the heat in the system is released along with the discharge of the electrode water, and the anode water containing oxidizing gas remains in the electrode chamber after normal operation. Since it is necessary to perform the hot water washing operation after discharging, the hot water washing operation cannot be started immediately after the normal operation.

  3) The daily dialysis treatment time tends to be longer due to the implementation of night dialysis, etc., and the waiting time until the next day dialysis is shortened. Need to finish. However, as described above, since it takes time to raise the temperature of the cleaning water, it is difficult to meet the demand for cleaning in this short time.

  As a technique related to the present invention, Patent Document 1 describes a technique for performing hot water sterilization in the production of purified water for pharmaceuticals. However, the technique described in Patent Document 1 is subject to treatment with the present invention. Is different from the purified water for pharmaceutical production and does not mention dialysate. Further, the apparatus described in Patent Document 1 has a circulation path through which hot water can be circulated between a system equipped with an RO membrane module and EDI in this order and a raw water tank, but treated water that has passed through the RO membrane module and EDI. Is passed through only the heat exchanger, and pretreatment means including at least activated carbon is not provided in the hot water circulation path. Therefore, as in the present invention, after passing hot water sequentially through the raw water tank, the pretreatment means, the RO membrane module, and the EDI, a circulation path for circulating the EDI demineralized water, electrode water, and concentrated water to the raw water tank is provided. Is different.

  Furthermore, the heating method is different from the present invention. In the apparatus described in Patent Document 1, since a heater is provided in the circulation pipe, the heating efficiency is lower than the case where the raw water tank is provided with a heating means, and the desired heating is performed. May take a long time.

  In addition, as a technique related to the present invention, Patent Document 2 describes a technique that uses an RO membrane and EDI in the production of dilution water for dialysis fluid preparation. Not mentioned.

  In addition, as a technique related to the present invention, Patent Document 3 describes a technique for performing hot water sterilization in the system in the production of dilution water for preparing dialysate, but the apparatus described in Patent Document 3 The raw water tank, the pretreatment means, and the RO membrane module are provided in this order, and are different from the present invention in that the EDI is not provided.

  Even if the idea of hot water cleaning according to Patent Document 1 is considered in the apparatus described in Patent Document 3, the idea of returning EDI electrode water containing an oxidizing gas to the raw water tank for the reasons described above does not occur. . Therefore, the problem of enlargement of the raw water tank due to the fact that the electrode water cannot be returned to the raw water tank as in the above problem 1) still remains.

  Accordingly, the present invention solves the above-mentioned problems 1) to 3), and allows the apparatus to be washed with hot water in a relatively short time to maintain the apparatus at a high degree of cleanliness for a long period of time. It aims at providing the manufacturing apparatus of the dilution water for preparation. A further object is to allow the raw water tank to be installed with a minimum size so that it can be used in hospital facilities.

  The apparatus for producing dialysate preparation dilution water according to the present invention includes a raw water storage tank for storing raw water, pretreatment means including at least activated carbon for pretreating raw water supplied under pressure from the raw water storage tank, and pretreatment means. A reverse osmosis membrane module that separates raw water that has been pretreated and pressurized and supplied into reverse osmosis membrane into permeated water and concentrated water, and the permeated water from the reverse osmosis membrane module is separated into desalted water, electrode water, and concentrated water An electric regenerative pure water production apparatus (EDI), a purified water storage tank for storing deionized water of the electric regenerative pure water production apparatus as purified water, and a purified water storage tank for demineralized water of the electric regenerative pure water production apparatus And a purified water supply means for supplying purified water stored in the purified water storage tank as dialysate preparation dilution water.

  In order to solve the above problems, according to one aspect of the present invention, the permeated water and concentrated water of the reverse osmosis membrane module, and the demineralized water, electrode water and concentrated water of the electric regenerative pure water production apparatus are respectively A circulation path is provided to return to the raw water storage tank. Furthermore, the raw water in the raw water storage tank, the permeated water and the concentrated water of the reverse osmosis membrane module, and the electric regenerative pure water production apparatus when performing hot water washing of the reverse osmosis membrane module and the electric regenerative pure water production apparatus A heating means for heating circulating water into the raw water storage tank of the demineralized water, electrode water and concentrated water is attached to the raw water storage tank. Furthermore, when performing the hot water cleaning, the desalted water supply path is returned to the raw water storage tank so that the desalted water in the desalted water supply path is not supplied to the purified water storage tank. First flow path switching means capable of switching to the desalted water circulation path is provided.

  In such an apparatus according to the present invention, the permeated water and concentrated water of the reverse osmosis membrane module, the desalted water, the electrode water and the concentrated water of the electric regenerative pure water production apparatus are circulated to the raw water storage tank via the circulation path. The temperature is raised by the heating means attached to the raw water storage tank, and the reverse osmosis membrane module and the electric regenerative pure water production apparatus are subjected to hot water washing. Therefore, the permeated water (secondary side permeated water) and concentrated water (primary side concentrated water) of the reverse osmosis membrane module, and the desalinated water, electrode water, and concentrated water of the electric regenerative pure water production device are recovered in the raw water storage tank. Thus, the reverse osmosis membrane module and the electric regenerative pure water production apparatus are washed with hot water without reducing the amount of hot water circulating water, and the washing effect of hot water is maintained high. Further, in a system including a raw water storage tank, a reverse osmosis membrane module, and an electric regenerative pure water production apparatus in this order, before the reverse osmosis membrane module has activated carbon capable of removing the oxidizing gas contained in the anode water. By providing the treatment means, it is possible to return the electrode water of the electric regenerative pure water production apparatus to the raw water storage tank upstream of the pretreatment means, and the water recovery rate becomes 100%. For this reason, unlike the conventional configuration where it is necessary to discharge the electrode water of the electric regenerative pure water production apparatus, it is not necessary to increase the size of the raw water storage tank in anticipation of the discharge amount of the electrode water. It is possible to provide a device for producing dialysate-preparing dilution water having a size that can be easily transported and installed. In addition, the manufacturing apparatus of the present application is very suitable as an apparatus used in a hospital facility because it does not require a facility for draining the electrode water of an electric regeneration type pure water manufacturing apparatus.

  In addition, since the raw water and the circulating water in the circulation path are gradually heated by the heating means, high-temperature hot water is not supplied to the reverse osmosis membrane at once, and the reverse osmosis membrane and the electric regenerative pure water production apparatus are It can be washed at the desired temperature conditions. In addition, the total amount of circulating water is not reduced, but the whole amount is heated by the heating means attached to the raw water storage tank. As a result, high heating efficiency can be obtained, and the temperature can be raised to the target temperature in a short time. Since it does not take time to raise the temperature to the target temperature, it is possible to finish the desired hot water cleaning in a short time, and it is possible to easily cope with the cleaning time at night which is getting shorter. Furthermore, since the heated hot water is passed not only from the reverse osmosis membrane module and the electric regenerative pure water production apparatus but also from the raw water storage tank to the pretreatment means, efficient hot water cleaning of the pretreatment means is also possible. Thus, bacterial contamination and the like in the pretreatment means can be more appropriately prevented, and excellent cleaning of the entire system becomes possible. Since cleaning with excellent performance is possible in a short time, it is possible to easily handle dilution water production in a central dialysis system that requires production of a relatively large amount of dilution water for preparing dialysate.

  According to the apparatus for producing dialysate preparation dilution water according to the present invention, the electrode water that has passed through the electric regeneration type pure water production apparatus in hot water cleaning can be returned to the raw water storage tank. Minimize and allow the device to be used in hospital facilities.

  Furthermore, the raw water and the circulating water for cleaning the reverse osmosis membrane module and the electric regenerative pure water production apparatus can be efficiently heated to a desired temperature, and the reverse osmosis membrane module, the electric regenerative pure water production apparatus, The treatment means can also be efficiently washed with hot water in a short time, and can easily cope with the production of diluting water for preparing dialysate in the central dialysis system.

It is an equipment system diagram of a manufacturing device of dilution water for dialysate preparation concerning a 1st embodiment of the present invention. FIG. 5 is a schematic cross-sectional view showing a configuration example of another EDI that can be substituted for the EDI in FIG. 1.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 shows an apparatus for producing dialysate-preparing dilution water according to the first embodiment of the present invention, and shows an example in which the RO membrane module has one stage. 1 includes a raw water storage tank 3 for storing the supplied raw water 2, a pressurizing pump 4 for pressurizing and supplying the raw water in the raw water storage tank 3, Pretreatment means 5 for pretreating the raw water supplied by the pressure pump 4, a high pressure pump 6 for further pressurizing and supplying the raw water pretreated by the pretreatment means 5, and reverse osmosis of the raw water supplied by the high pressure pump 6 RO membrane module 8 that separates permeated water and concentrated water by a membrane (hereinafter abbreviated as RO membrane), and electric regeneration type that separates the permeated water from RO membrane module 8 into desalted water, electrode water, and concentrated water Pure water production apparatus (hereinafter abbreviated as EDI) 15, purified water storage tank 9 that stores demineralized water from EDI 15 as purified water, and dilution of purified water stored in purified water storage tank 9 for dialysis fluid preparation Purified water supply means for supplying as water 10 And a water pump 11 of Te.

  The pretreatment means 5 includes at least activated carbon, and includes, for example, at least one of various filter membranes (MF membrane, UF membrane, NF membrane, etc.), softener, and filter.

  The EDI 15 is desalted by, for example, filling a chamber defined by the cation exchange membrane 16 and the anion exchange membrane 17 with an ion exchanger (ion exchange resin, monolithic organic porous ion exchanger, ion exchange fiber, etc.). The chamber 18 is configured, and two concentration chambers 19a and 19b are provided on both sides of the desalting chamber 18, and the desalting chamber 18 and the concentration chambers 19a and 19b are divided into a cathode chamber 20a having a cathode and an anode chamber having an anode. 20b. An anion exchange membrane 16 or a cation exchange membrane 17 is also provided between the concentration chamber 19a and the electrode chamber 20a and between the concentration chamber 19b and the electrode chamber 20b. Although FIG. 1 shows a flat plate type EDI, a spiral type or a concentric type may be used. Moreover, although the case where the number of the desalination chamber 18 is one is illustrated, as shown in FIG. 2, another ion exchange membrane (anion exchange membrane 17 in this case) is provided in the desalination chamber 18, and the desalination chamber 18 is provided. The structure which divides | segments may be sufficient.

  In the case of the configuration of FIG. 1, the permeated water from the RO membrane module 8 is branched and passes through the ion exchanger layer filled in the desalting chamber 18, the concentration chambers 19 a and 19 b, and the electrode chambers 20 a and 20 b. It has become. In the case of the configuration of FIG. 2, it is preferable that the permeated water of the RO membrane module 8 passes through the second desalting chamber 18b after passing through the first desalting chamber 18a. In any case, a voltage is applied between the cathode of the electrode chamber 20a and the anode of the electrode chamber 20b, and the water flows through the cation exchange membrane 16 and the anion exchange membrane 17 on both sides of the desalting chamber 18. By applying a direct current in a perpendicular direction, impurity ions in the RO membrane permeated water flowing through the desalting chamber 18 are electrically excluded into the RO membrane permeated water flowing through the concentrating chambers 19a and 19b. Demineralized water is produced. The RO membrane permeated water in the concentration chambers 19a and 19b that has received the impurity ions (salts) from the desalting chamber 18 is discharged out of the EDI 15 as concentrated water. Further, the RO membrane permeate flowing in the electrode chambers 20a and 20b contains electrolytic products such as hydrogen gas, oxygen gas, chlorine gas, ozone gas, hydrogen peroxide, and other oxidizing gas, and is discharged outside the EDI 15 as electrode water. Discharged.

  The concentrated water and permeated water of the RO membrane module 8, the demineralized water of the EDI 15, the electrode water and the concentrated water are the concentrated water circulating path 12 and the permeated water circulating path 13 from the RO membrane module 8, and the desalted water circulating path from the EDI 15, respectively. 21, it is configured to be circulated to the raw water storage tank 3 through the concentrated water circulation path 22 and the electrode water circulation path 23. The demineralized water circulation path 21 of the EDI 15 is connected via a three-way valve 25 to a demineralized water supply path 24 sent from the demineralized chamber 18 of the EDI 15 to the purified water storage tank 9. By the three-way valve 25 (first flow path switching means), the desalted water supply path 24 that sends the desalted water from the desalting chamber 18 of the EDI 15 to the purified water storage layer 9 in the production of the dilution water for dialysate preparation, At the time of washing with hot water before production of the dialysate preparation dilution water, the hot water can be switched to the desalted water circulation path 21 that sends the hot water from the desalting chamber 18 of the EDI 15 to the raw water storage tank 3.

  Further, the purified water stored in the purified water storage tank 9 is supplied as the dialysate preparation dilution water 10 by the water pump 11 when the dialysate preparation dilution water is manufactured, or the dialysate preparation dilution water is manufactured. It is configured to be circulated to the raw water storage tank 3 through the purified water circulation path 14 switched by the three-way valve 26 (second flow path switching means) at the time of previous hot water washing.

  The raw water storage tank 3 is provided with a heating means 28 for heating the raw water and the circulating water collected through the circulation paths 12, 13, 14, 21, 22, and 23. As this heating means, a general heating means such as a heater may be used as it is.

  When the RO membrane module 8 and the EDI 15 are washed with hot water before the dialysate preparation dilution water is manufactured, the desalted water supply path 24 is connected only to the desalted water circulation path 21 by the three-way valve 25 and the on-off valve 27 is opened. The required amount of raw water 3 is stored in the raw water storage tank 3. Thereafter, the heating means 28, the pressure pump 4 and the high pressure pump 6 are operated. Thereby, the raw water in the raw water storage tank 3 is passed through the pretreatment means 5, the RO membrane module 8 and the EDI 15 in this order, and again through the circulation paths 14, 21, 22, and 23. Reflux to 3. By repeating such circulation, the purity of the raw water in the raw water storage tank 3 increases each time the pretreatment means 5, the RO membrane module 8 and the EDI 15 pass, and the temperature is gradually raised by the heating means 28. Thus, the RO membrane module 8 and the EDI 15 are subjected to hot water cleaning.

  However, the entire system including the pretreatment means 5 to the purified water storage tank 9 can be cleaned with the heated hot water. This is because the three-way valve 25 switches the desalted water supply path 24 from the connection with the desalted water circulation path 21 to the connection with the purified water storage tank 9, and at the same time, the three-way valve 26 switches from the purified water storage tank 9 to the purified water circulation path. It becomes possible by switching to 14.

  Further, in the present embodiment, a bypass circuit 29 is provided that connects the outlet side of the pressurizing pump 4 and the inlet side of the high-pressure pump 6 to bypass the pretreatment means 5. The bypass circuit 29 can be switched between a path for allowing the pretreatment means 5 to pass through and a path for preventing the passage of the pretreatment means 5, whereby the temperature of the hot water passing through the pretreatment means 5 and the passage after the RO membrane module 8 are passed. It is possible to switch to the temperature of hot water to be used.

  The apparatus 1 for producing dialysate-preparing dilution water configured as described above has several effects as follows.

  Permeated water and concentrated water separated by the RO membrane module 8, demineralized water of EDI 15, electrode water, and concentrated water are circulated to the raw water storage tank 3 via the respective circulation paths 12, 13, 21, 22, 23, The temperature is gradually raised by the heating means 28 attached to the raw water storage tank 3. Therefore, the total amount of the circulating water that has been circulated and heated without being reduced is supplied to the RO membrane module 8 and the EDI 15 with hot water, and the use efficiency of the hot water is maintained high. In particular, in a system including the raw water storage tank 3, the RO membrane module 8 and the EDI 15 in this order, the pretreatment means 5 including activated carbon capable of removing the oxidizing gas contained in the anode water is provided in the preceding stage of the RO membrane module 8. As a result, the electrode water of the EDI 15 can be returned to the raw water storage tank 3 upstream of the pretreatment means 5, so that the water recovery rate becomes 100%. For this reason, unlike the conventional configuration which requires discharging the EDI electrode water, it is not necessary to increase the size of the raw water storage tank 3 in anticipation of the discharge amount of the electrode water.

  In the case of the conventional configuration in which the electrode water cannot be circulated, for example, if the discharge amount of the electrode water from the EDI is 30 liters per hour, 120 liters of water is lost after 4 hours of hot water washing. Further, as shown in FIG. 1, in the system for returning water from the raw water storage tank 3 to the raw water storage tank 3 again through the RO membrane module 8 and EDI 15 and the like, the components other than the raw water storage tank 3 are also used in order not to run idle. It is necessary to keep water. If the amount of retained water is, for example, 70 liters, 190 liters of raw water must be stored in the raw water storage tank 3 in the conventional configuration together with the amount of lost water in the electrode water. That is, the raw water storage tank 3 must be large enough to accommodate at least 190 liters of raw water. On the other hand, in the present invention in which the electrode water can be returned to the raw water storage tank 3, the hot water in the system is not reduced. In the above numerical example, according to the present invention, the capacity of the raw water tank can be reduced to half or less than the conventional configuration.

  Therefore, unlike the conventional configuration in which EDI electrode water needs to be discharged, it is possible to provide a device for producing dialysate-producing diluted water that can be easily transported and installed in a hospital facility. In addition, the production apparatus of the present invention does not require an electrode water discharge line, so there is no need to prepare a waste water treatment facility accompanying the production apparatus, and it is suitable as a production apparatus for dialysate produced in a hospital facility. .

  In addition, since the circulating water is gradually heated by the heating means 28 as described above, the inside of the RO membrane module 8 and the EDI 15 is not exposed to high-temperature hot water all at once, and the RO membrane, ion exchanger, etc. Washed at desired temperature conditions. Furthermore, the total amount of the circulating water is not reduced, but the entire amount is heated by the heating means 28 attached to the raw water storage tank 3, and since there is no discharge of hot water to the outside of the system, the temperature is raised in the raw water storage tank. The heat capacity for can be maintained in a large state. As a result, high heating efficiency can be realized, and the temperature can be raised to the target temperature in a short time. By shortening the temperature raising time, the predetermined cleaning time is also shortened, and it becomes possible to perform sufficient cleaning during the nightly cleaning possible time.

  Further, since the heated hot water is passed through the pretreatment means 5, not only the RO membrane module 8 and the EDI 15 but also the pretreatment means 5 can be efficiently washed with hot water. In this case, bacterial contamination and the like in the pretreatment means 5 can be prevented more appropriately. Furthermore, the purified water storage tank 9 can also be washed with hot water using circulating water, and the whole system can be cleaned efficiently and efficiently.

  Furthermore, by using the flow path switching by the bypass circuit 29, even when the hot water flow temperatures that are optimum for the pretreatment means 5, the RO membrane module 8 and the EDI 15 are different from each other, each part is optimized. It becomes possible to wash more appropriately at the hot water temperature. For example, when the bypass circuit 29 is closed and water is passed only to the pretreatment means 5 side, hot water having an optimum temperature for cleaning the pretreatment means 5 can be passed through the pretreatment means 5 and the bypass circuit 29 is opened. When water is not passed through the pretreatment means 5 side, hot water having a temperature optimal for cleaning the RO membrane 8 module and the EDI 15 can be passed through the RO membrane 8 module and the EDI 15.

  Further, by operating the three-way valves 25 and 26, the temperature of the hot water circulated between the raw water storage tank 3, the RO membrane module 8 and the EDI 15 reaches a predetermined temperature, and after circulating for a predetermined time, the RO membrane module The hot water that has passed through 8 and EDI 15 is supplied to the purified water storage tank 9, and the purified water is circulated between the purified water storage tank 9 and the raw water storage tank 3 via the purified water circulation path 14 by the water supply pump 11. It is also possible to wash hot water from the raw water storage tank 3 to the purified water storage tank 9 with water. That is, the purified water in the purified water storage tank 9 is supplied from the raw water storage tank 9 using the water pump 11 when the cleaning is advanced to some extent by circulating between the raw water storage tank 3 and the RO membrane module 8 and the EDI 15 for a predetermined time. 3 can be circulated. As a result, it is possible to perform final hot water washing using cleaner purified water, and production of diluted water can be appropriately started immediately after the final washing.

  While the present invention has been described with reference to the embodiment, the present invention is not limited to the above embodiment. Various modifications that can be understood by those skilled in the art can be made to the shape and details of the present invention within the scope of the technical idea of the present invention.

  For example, in the above description, an apparatus in which one RO membrane module is installed on the flow path between the pretreatment means 5 and the EDI 15 is shown. However, even if the RO membrane module 8 is arranged in at least two stages in series, Good. Also in the case of this apparatus, a circulation path for returning the concentrated water and permeated water of the added RO membrane module to the raw water storage tank 3 and a high-pressure pump can be added as appropriate. By providing such a multistage RO membrane module, it is possible to further increase the cleanliness of the dilution water when producing the dilution water for preparing dialysate.

  INDUSTRIAL APPLICABILITY The present invention can be applied to the production of any dialysate-preparing dilution water having pretreatment means, RO membrane module, and EDI. This is suitable for the production of dilution water for liquid preparation.

DESCRIPTION OF SYMBOLS 1 Production apparatus for dilution water for dialysate preparation 2 Raw water 3 Raw water storage tank 4 Pressure pump 5 Pretreatment means 6 High pressure pump 8 Reverse osmosis membrane module 9 Purified water storage tank 10 Dilution water 11 for dialysate preparation Purified water supply means Water pump 12 Concentrated water circulation path 13 of RO membrane module Permeated water circulation path 14 of RO membrane module Purified water circulation path 15 EDI
16 Cation exchange membrane 17 Anion exchange membrane 18, 18a, 18b Desalination chamber 19a, 19b Concentration chamber 20a, 20b Electrode chamber 21 Desalted water circulation path 22 Concentrated water circulation path 23 Electrode water circulation path 24 Desalted water supply path 25, 26 Three-way valve 27 On-off valve 28 Heating means 29 Bypass circuit

Claims (4)

Raw water storage tank for storing raw water,
Pretreatment means including at least activated carbon for pretreating raw water supplied under pressure from the raw water storage tank;
A reverse osmosis membrane module that separates raw water that has been pretreated from the pretreatment means and supplied under pressure with a reverse osmosis membrane into permeated water and concentrated water;
An electric regenerative pure water production apparatus (EDI) for separating permeated water from the reverse osmosis membrane module into demineralized water, electrode water and concentrated water;
A purified water storage tank for storing demineralized water of the electric regenerative pure water production apparatus as purified water;
A demineralized water supply path for supplying demineralized water of the electric regenerative pure water production apparatus to the purified water storage tank;
Purified water supply means for supplying purified water stored in the purified water storage tank as dialysate preparation dilution water,
Circulation paths for returning the permeated water and concentrated water of the reverse osmosis membrane module and the desalted water, electrode water and concentrated water of the electric regenerative pure water production apparatus to the raw water storage tank, respectively.
Attached to the raw water storage tank, when performing hot water washing of the reverse osmosis membrane module and the electric regenerative pure water production apparatus, raw water in the raw water storage tank, permeated water and concentrated water of the reverse osmosis membrane module, Heating means for heating the deionized water, electrode water, and concentrated water circulating in the raw water storage tank of the electric regenerative pure water production apparatus;
When performing the hot water washing, the demineralized water supply path is used so that the demineralized water in the demineralized water supply path is not supplied to the purified water storage tank, and the demineralized water of the electric regenerative pure water production apparatus is used as the raw water storage tank. First flow path switching means capable of switching to a demineralized water circulation path to return to
An apparatus for producing diluting water for preparing dialysate. A purified water circulation path for returning purified water in the purified water storage tank to the raw water storage tank;
A second flow path switching means capable of switching the purified water supplied by the purified water supply means to the flow to the purified water circulation path;
When performing the hot water cleaning, the first flow path switching means supplies demineralized water in the demineralized water supply path to the purified water storage tank, and the second flow path switching means stores the purified water storage tank. 2. The apparatus for producing diluted water for preparing dialysate according to claim 1, wherein the purified water is configured to flow through the purified water circulation path.   The dialysate preparation according to claim 1 or 2, wherein a plurality of the reverse osmosis membrane modules connected in series in multiple stages are arranged between the pretreatment means and the electric regeneration type pure water production apparatus. Dilution water production equipment.   The dialysate preparation according to any one of claims 1 to 3, wherein the pretreatment means further includes at least one of a softener, a filter, and a filter membrane. Dilution water production equipment.

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