JP6953070B2 - Medical purified water production equipment - Google Patents

Description

The present invention relates to an apparatus for producing purified medical water such as water for artificial dialysis, and a method for producing purified medical water using the apparatus.

Conventionally, an apparatus for producing purified water in which an activated carbon apparatus, a membrane separation apparatus, an EDI apparatus and the like are combined, and a method for producing purified water using the apparatus are known.
When producing purified water using these purified water production devices, it is important to sterilize the inside of the device from the viewpoint of hygiene.

Patent Document 1 describes a medical purified water production apparatus having a combination of a first circulation line and a second circulation line (claim 1), and a medical purified water having a combination of a first circulation line and a third circulation line. An invention for sterilizing the manufacturing apparatus (claim 3) of the above with hot water is described.

Japanese Patent No. 5923827

INDUSTRIAL APPLICABILITY When producing medical purified water by a medical purified water production apparatus, the present invention can heat sterilize the inside of the apparatus without causing a sudden temperature change in heating and cooling for thermal sterilization of the apparatus. Another object of the present invention is to provide an apparatus for producing purified water for medical use, which can easily cool the inside of the apparatus after heat sterilization, and an operation method thereof.

The present invention includes an activated carbon adsorption device (hereinafter referred to as "activated carbon device") (3).
Reverse osmosis membrane treatment device (hereinafter referred to as "RO device") (5),
An RO water tank (6) equipped with a heating means (6a) for storing treated water (hereinafter referred to as "RO water") treated by the RO device (5), and
It has a heat exchanger (8) with raw water cooling means connected to the RO water tank (6).
The raw water supply source and the activated carbon device (3) are connected by the raw water supply line (11,12,13).
The activated carbon device (3) and RO device (5) are connected by a pretreatment water line (14).
The RO device (5) and RO water tank (6) are connected by the RO water line (17),
The RO water outlet of the RO water tank (6) is connected to the first end of the first water intake line (18), the middle part of the first water intake line (18) is connected to the water intake part, and the first water intake line (18) is connected. ) Is connected to the RO water inlet side of the RO water tank (6).
The RO water tank (6) and the heat exchanger (8) share a part with the first water intake line (18) from the RO water tank (6) to the heat exchanger (8), and the water inlet line (21). A medical purified water production device connected by a water discharge line (22) from the heat exchanger (8) to the RO water tank (6).
It has a circulation line that circulates hot water or cooling water when the production operation of purified medical water is stopped.
The circulation line is a combination of a first circulation line, a second circulation line, and a fourth a circulation line.
The first circulation line is a circulation line that returns from the RO water tank (6) to the RO water tank (6) through the water inlet line (18, 21), the heat exchanger (8), and the water outlet line (22).
The second circulation line is from the RO water tank (6) to the first intake line (18), the first return line (23), the raw water supply line (13), the activated carbon device (3), and the pretreatment water line (14). , RO device (5), RO water line (17) and back to RO water tank (6).
The 4a circulation line is a circulation line that returns from the RO water tank (6) through the first intake line (18) to the RO water tank (6), and is a first intake line located near the RO water tank (6). A part of (18) has a narrow passage that has a narrower flow path than the other parts, and further has a bypass flow path with an on-off valve that connects the upstream side and the downstream side between the barriers. , A device for producing purified water for medical use, and a method for producing purified water for medical use using the apparatus.

Further, the present invention includes an adsorption device using activated carbon (hereinafter referred to as "activated carbon device") (3).
Reverse osmosis membrane treatment device (hereinafter referred to as "RO device") (5),
An RO water tank (6) equipped with a heating means (6a) for storing treated water (hereinafter referred to as "RO water") treated by the RO device (5), and
It has a heat exchanger (8) with raw water cooling means connected to the RO water tank (6).
The raw water supply source and the activated carbon device (3) are connected by the raw water supply line (11,12,13).
The activated carbon device (3) and RO device (5) are connected by a pretreatment water line (14).
The RO device (5) and RO water tank (6) are connected by the RO water line (17),
The RO water tank (6) and heat exchanger (8) are the water inlet line (21) from the RO water tank (6) to the heat exchanger (8), and the heat exchanger (8) to the RO water tank (6). Connected by the flood line (22) to
In addition, an electroregenerative deionization device (hereinafter referred to as "EDI device") (9) is provided.
The RO water tank (6) and the EDI device (9) are connected by the second RO water line (31).
The EDI device (9) and the EDI water tank (10) for storing the treated water treated by the EDI device (9) (hereinafter referred to as "EDI water") are connected by an EDI water line (32).
A medical purified water production device in which an EDI water tank (10) is connected to an intake line (18).
It has a circulation line that circulates hot water or cooling water when the production operation of purified medical water is stopped.
The circulation line is a combination of a first circulation line, a third circulation line, and a fourth b circulation line.
The first circulation line is a circulation line that returns from the RO water tank (6) to the RO water tank (6) through the water inlet line (21, 31), the heat exchanger (8), and the water outlet line (22).
The third circulation line is from the EDI water tank (10) to the intake line (18), line (23), raw water supply line (13), activated carbon device (3), pretreatment water line (14), RO device (5). ), 1st RO water line (17), RO water tank (6), 2nd RO water line (31), EDI device (9), circulation line returning to EDI water tank (10) through EDI water line (32) And
The 4b circulation line passes from the EDI water tank (10) through the first intake line (18) to the RO water tank (6), the second RO water line (31), the EDI device (9), and the EDI water line (32). It is a circulation line that returns to the EDI water tank (10) via Further, a medical purified water production device having a bypass flow path with an on-off valve that connects the upstream side and the downstream side between the blind roads, and the production of medical purified water using the apparatus. Provide a method.

According to the medical purified water production apparatus of the present invention and the operation method using the same, it is possible to regularly sterilize the portion in the production apparatus where chlorine is removed and bacteria are likely to grow at a sufficient flow rate. Therefore, the safety against the risk of bacterial contamination is enhanced, and it becomes easy to achieve a high degree of cleaning inside the device, especially in the production of water for artificial dialysis.

The explanatory view of the production flow of the medical purified water of this invention. A cross-sectional view showing a bottleneck formed in a line. The explanatory view of the production flow of the medical purified water of this invention which is another embodiment. The figure which shows the change of the viable cell count when the manufacturing method of the medical purified water of Example 1 and Comparative Example 1 was carried out.

(1) Medical purified water production equipment and its operation method shown in Fig. 1 <Medical purified water production operation>
The raw water (tap water or groundwater) is sent to the prefilter 1 by the first raw water line 11, and if there is a large foreign substance, it is removed.
The water treated by the pre-filter 1 is sent to the water softening device 2 by the second raw water line 12, and the amount of hardness components is reduced.
The water treated by the water softening device 2 is sent to the adsorption device (activated carbon device) 3 using activated carbon by the third raw water line 13, and the amount of chlorine in the raw water is reduced.
From the raw water source to the activated carbon device 3, the raw water pump 61 is driven to send water. The pre-filter 1 and the water softening device 2 may not be installed depending on the quality of the raw water. Further, when used for producing purified water for artificial dialysis, a heater or a heat exchanger for raising the water temperature in the cold season may be provided in front of the pre-filter 1.

The water treated by the activated carbon device 3 is sent to the reverse osmosis membrane treatment device (RO device) 5 by the pretreatment water line 14. An RO device pump 62 is installed in the pretreatment water line 14.
A line heater 4 as an auxiliary heating means can be installed in the pretreatment water line 14 as needed, but in the embodiment shown in FIG. 1, a dead space may occur and the viable cell count may increase. It is desirable not to install it because of the high cost and the need to secure a mounting place.

A known RO device 5 can be used, and for example, device models VCR40 series, VCR80 series, NER40 series, NER80 series, SHR series and the like sold by Daisen Membrane Systems Co., Ltd. can be used. can.
However, as the RO membrane module, it is necessary to use a heat-resistant RO membrane module using a heat-resistant material such as a membrane material and an adhesive member.
As the RO apparatus 5, a device having a processing capacity (capacity for producing treated water) of 30 to 5000 L / hr can be used, but the RO apparatus 5 is not limited to the above range and is appropriately selected according to the amount of purified water supplied. can do.

The treated water (RO water) treated by the RO device 5 is sent to the RO water tank 6 by the RO water line 17 and stored.
A heater 6a is installed in the RO water tank 6 as a main heating means, and the RO water can be heated by the heater 6a.
Further, a thermometer is installed in the RO water tank 6 so that the water temperature in the tank can be monitored from the outside.
Further, in order to equalize the water temperature in the tank, a stirring device can be attached if necessary.
A part of the concentrated water generated by the RO device 5 is discharged from the concentrated water line 16a, and the rest is returned to the pretreatment water line 14 by driving the concentrated water circulation pump 64.

The water storage capacity of the RO water tank 6 can be, for example, 100 to 3000 L. The RO water tank 6 is made of metal such as stainless steel.
The shape of the RO water tank 6 is not particularly limited, but from the viewpoint of preventing the liquid from remaining inside the tank and facilitating the flow of the liquid, a RO water tank 6 having a conical or quadrangular pyramid-shaped bottom is used. preferable.

The RO water tank 6 has a ventilation hole with an air filter to prevent bacteria and the like from entering from the outside atmosphere, and if necessary, an ultraviolet lamp can be attached inside for the purpose of sterilization. ..

It is preferable to install a water level gauge in the RO water tank 6 so that the operation of the RO device 5 can be started or stopped according to the water level. For example, the upper limit and the lower limit of the water level in the RO water tank 6 are determined in advance, the operation of the RO device 5 is stopped when the upper limit is reached, and conversely, the RO device 5 is stopped when the lower limit is reached. Try to start the operation.

The RO water in the RO water tank 6 is sent to the ultrafiltration membrane device (UF device) 7 by the first intake line 18, and endotoxin, bacteria, and the like are removed. The UF device 7 may be omitted.
An intake pump (UF device pump) 63 is installed in the first intake line 18.

The purified water treated by the UF device 7 is sent to the artificial dialysate preparation device 50 via the second water intake line 19 and the third water intake line 20 branched from the second water intake line 19.
The second water intake line 19 is further connected to the RO water tank 6, and the purified water that has not been taken in by the artificial dialysate preparation device 50 via the third water intake line 20 is returned to the RO water tank 6.

In the medical purified water production apparatus of the present invention, a combination of a first circulation line, a second circulation line, and a fourth a circulation line that circulates hot water or cooling water when the production operation of the medical purified water is stopped. It has a circulation line consisting of.
The first circulation line is a circulation line that returns from the RO water tank 6 to the RO water tank 6 through the water inlet line 21 (partly shared with the water intake line 18), the heat exchanger 8, and the water discharge line 22. ..
The heat exchanger 8 is connected to the first raw water line 11 by a cooling water line 24 so that raw water as a cooling medium can be supplied into the heat exchanger 8.
The heat exchanger 8 has a drainage line 25 for raw water used for cooling.
Since the heat exchange water is hot immediately after the start of cooling operation after the completion of hot water sterilization, a storage pot equipped with a thermometer is provided in the drain line 25, and raw water is provided until the water temperature in the storage pot drops to a predetermined temperature. It is desirable to mix with and cool and then drain.
Since the drainage (raw water) from the drainage line 25 is tap water or groundwater, it can be used for other purposes.

The second circulation line passes from the RO water tank 6 through the first intake line 18, the first return line 23, the raw water supply line 13, the activated carbon device 3, the pretreatment water line 14, the RO device 5, and the RO water line 17. It is a circulation line returning to the RO water tank 6.
The 4a circulation line is a circulation line that returns from the bottom of the RO water tank 6 (RO water outlet) to the RO water inlet of the RO water tank 6 through the first intake line 18, the UF device 7, and the second intake line 19. , RO water flows from the RO water outlet side (upstream side) to the RO water inlet side (downstream side).
A part of the second intake line 19 located near the RO water tank 6 has a bottleneck 78 whose flow path is narrower than the other parts, and further opens and closes to connect the upstream side and the downstream side with the bottleneck 78 in between. It has a bypass flow path 26 with a valve 79.
Bottleneck 78, in the embodiment of FIG. 1, the narrow path 78 by the flow path of the flow regulating valves partially close are formed. Partially closed means that 30 to 70% of the part is closed (70 to 30% is closed), assuming that the cross-sectional area of the flow path when the bottleneck (flow rate adjusting valve ) 78 is fully opened is 100%. It is preferably open).
In addition, as shown in FIG. 2, the bottleneck 19a may be formed by reducing the inner diameter of a part of the second intake line 19.

<Sterilization and cooling operation>
When the production operation of purified water by the production apparatus shown in FIG. 1 is continuously carried out, the production operation of purified water is periodically stopped and the sterilization and cooling operations are carried out.

In the manufacturing apparatus shown in FIG. 1, the medical purified water manufacturing operation is performed with the on-off valve 79 of the bypass flow path 26 closed.
The RO water (UF water) in which the RO water in the RO water tank 6 is treated by the UF device 7 is sent from the third water intake line 20 to the artificial dialysate preparation device 50 via the second water intake line 19. The UF water that has not been taken in is returned to the RO water tank 6 through the second intake line 19 and the fourth circulation line including the bottleneck (flow rate adjusting valve) 78.
Since the fourth a circulation line has a long overall length, the pressure may drop in the middle and it may become difficult to flow. However, in the manufacturing apparatus of FIG. 1, a bottleneck ( flow rate adjusting valve) 78 is provided, and the liquid flow of RO water (UF water) is pressurized so that RO water (UF water) can easily flow.
The position of the narrow path ( flow control valve) 78 is arranged in the range of 0.5L to 0.99L, where L is the line length from the RO water outlet at the bottom of the RO water tank 6 to the RO water inlet of the RO water tank 6. It is preferable that it is arranged in the range of 0.6 to 0.99 L, and it is more preferable that it is arranged in the range of 0.6 to 0.99 L.
During the production operation of purified medical water, RO water (UF water) passes through the bypass flow path 26 by opening the opening / closing valves 79 at appropriate intervals in order to prevent the liquid from staying in the bypass flow path 26. It is preferable to make it watered. For example, after the manufacturing operation for 30 minutes, the opening / closing valve 79 is opened for about 5 to 20 seconds so that RO water (UF water) can pass through the bypass flow path 26.

The sterilization operation is carried out according to the following procedure.
With the purified water production operation stopped, the RO water in the RO water tank 6 is heated by the heater 6a.
The temperature of RO water before heating is preferably room temperature or adjusted to 20 to 30 ° C., and is heated to a temperature of 70 ° C. or higher (preferably about 70 to 100 ° C.) by heating with the heater 6a. The temperature is gradually raised at 1 to 5 ° C./min, preferably 0.5 to 4 ° C./min.
The heating temperature is not limited to the above range and can be appropriately selected and changed depending on the RO membrane module used.

The pump 63 is driven to circulate in the first circulation line while heating and raising the temperature of the RO water in the RO water tank 6 at the above-mentioned temperature rising rate.
In parallel with the circulation operation of the first circulation line, the circulation operation of the second circulation line is performed.
Further, although the pressurizing pump 62 of the RO device is stopped, the concentrated water circulation pump 64 is operated to pass water to the concentrated water line 16b.

In this way, the circulation operation by the two circulation lines of the first circulation line and the second circulation line is carried out in parallel.
By the circulation operation of the first circulation line, the temperature of the RO water in the RO water tank 6 is raised evenly, and the RO water can be circulated to the second circulation line while being gradually heated and raised.
Therefore, compared to the case where hot water is circulated from the beginning, the thermal load on the equipment (particularly activated carbon, separation membrane, pipe joint, valves) in the second circulation line can be reduced, and finally Since hot water heated to about 80 to 90 ° C. is circulated, sufficient hot water sterilization is also carried out.
In addition, since the second circulation line has a long flow path and the temperature of hot water drops due to heat radiation from piping and equipment, the temperature of hot water as a sterilization medium can be lowered by heating with the line heater 4 as necessary. It is desirable to prevent it. By providing the line heater 4, more precise control of the heating rate and the heating temperature becomes easy. In the present embodiment, it is preferable to provide a bypass flow path 79 instead of the line heater 4.
In the sterilization operation, in order to carry out sufficient sterilization and suppress the thermal effect on the activated carbon and the separation membrane, after the temperature of the hot water passed through the RO device 5 reaches about 80 to 90 ° C. It is preferable to stop after circulating for at least 10 minutes.

In the sterilization operation using hot water, in addition to the above-mentioned circulation line, a fourth circulation line (UF device 7) consisting of an RO water tank 6, a first intake line 18, a UF device 7, a second intake line 19, and an RO water tank 6 is used. It is also carried out for the circulation line including). The hot water sterilization operation of the fourth circulation line including the UF device 7 is performed at the same time as the sterilization operation of the first circulation line.
When the sterilization operation of the 4a circulation line is performed, the operation is performed with the on-off valve 79 of the bypass flow path 26 open. When the sterilization operation of the 4a circulation line is performed with the opening / closing valve 79 of the bypass flow path 26 opened in this way, a sufficient amount of hot water can be circulated as compared with the case where the bypass flow path 26 is not provided. Even in the long 4a circulation line, the decrease in hot water temperature is small, which is preferable.
By leaving the bottleneck (flow rate adjusting valve) 78 as it is during the sterilization operation, the bottleneck (flow rate adjusting valve) 78 can also be sterilized.
Further, by changing the opening degree of the bottleneck (flow rate adjusting valve) 78 in small steps between 0 and 100% during the sterilization operation, it is possible to sterilize every corner of the bottleneck (flow rate adjusting valve) 78.

After the hot water sterilization operation for the circulation line is completed, a cooling operation for cooling the circulation line is carried out before restarting the production operation of purified medical water.
The cooling operation is carried out according to the following procedure.
After the hot water sterilization operation is completed, the heating in the RO water tank 6 is stopped, then the on-off valve 73 is opened, and raw water is supplied to the heat exchanger 8 as a cooling medium through the cooling water line 24.
Then, the RO water is cooled while performing the circulation operation of the first circulation line. The cooling rate at this time can be adjusted by adjusting the flow rate of the flow rate control valve 72 or the like.
The water temperature in the RO water tank 6 is gradually lowered by the circulation operation of the first circulation line, and finally is lowered to about 20 to 30 ° C. The temperature lowering rate is preferably adjusted at 0.1 to 5 ° C./min, more preferably 0.5 to 4 ° C./min.

While lowering the temperature of the RO water in the RO water tank 6 by the circulation operation of the first circulation line described above, the circulation operation of the second circulation line or the fourth a circulation line is carried out in parallel with the temperature reduction.
At this time, although the pressurizing pump 62 of the RO device is stopped, the concentrated water circulation pump 64 is operated to pass water to the concentrated water line 16b.

In this way, the circulation operation of the first circulation line and the second circulation line or the fourth a circulation line is carried out in parallel to cool.
Since the RO water is circulated in the second circulation line or the fourth a circulation line while gradually lowering the temperature of the RO water in this way, it is in the second circulation line as compared with the case where cold water (room temperature water) is circulated from the beginning. Thermal effects such as shrinkage due to a sudden temperature drop of the equipment (particularly activated carbon, separation membrane and pipe joints, valves) or the equipment in the 4a circulation line are reduced. In addition, the cooling operation does not require complicated operations such as starting and stopping intermittent water supply when directly supplying and cooling the raw water into the device, and enables a simple and smooth cooling operation.
When the cooling operation is performed on the fourth a circulation line including the UF device 7, the open / close valve 79 of the bypass flow path 26 is opened. The cooling operation of the 4a circulation line including the UF device 7 may be performed at the same time as the cooling operation of the second circulation line, or may be performed separately.
It is desirable that the sterilization operation and the cooling operation using hot water be carried out continuously without interruption.
In addition, the production operation of purified medical water is performed after the completion of hot water sterilization, but even at night and holidays when the artificial dialysis treatment is completed, the first circulation line, the second circulation line, and the fourtha circulation line including the UF device 7 are performed. It is preferable to continue the circulation operation (RO water circulation operation) in order to prevent the growth of bacteria.

(2) Manufacturing device for medical purified water shown in FIG. 3 and its operation method FIG. 1 shows that the manufacturing device shown in FIG. 3 was additionally equipped with an EDI device 9 and an EDI water tank 10, and the line was changed accordingly. It is different from the manufacturing equipment of.

The RO water in the RO water tank 6 is sent to the EDI device 9 on the second RO water line 31. A liquid feeding pump 65 to the EDI device 9 is installed in the second RO water line 31. In the device of FIG. 3, the line corresponding to the RO water line 17 of FIG. 1 is the first RO water line 17.

The EDI device 9 has an ion exchange chamber (demineralization chamber) in the center, two concentration chambers on both outer sides of the desalination chamber, and electrode chambers (positive and negative electrode chambers) on the outside of each of the concentration chambers. It is a known device having a deionized water (EDI treated water) that can be taken out by deionizing in an ion exchange chamber.
Examples of the EDI device 9 include JP-A-2007-252396, JP-A-2007-237062, JP-A-11-244853, JP-A-2001-239270, JP-A-2001-353498, and JP-A. In addition to those described in Japanese Patent Application Laid-Open No. 2004-74109, commercially available EDI system series, EDI system series, trade name MOLSEP (registered trademark) (sold by Daisen Membrane Systems Co., Ltd.), those used in Examples, etc. are used. be able to.
However, it is necessary to use heat-resistant members such as ion exchange resins, ion exchange membranes, and adhesives.

The operating conditions of the EDI device 9 are
The amount of liquid supplied from the RO water line 31 is preferably 50 to 4500 L / hr.
The amount of EDI-treated water (amount of desalinated water) is preferably 30 to 4000 L / hr.
The concentrated water flow rate is preferably a flow rate of 5% to 40% of the supply liquid amount.
The applied voltage is preferably 30 to 1000 V, the applied current is preferably 0.2 to 6 A, and the applied current density is preferably ^{0.05 to 4 A / dm 2.}

The EDI water treated by the EDI device 9 is sent to the EDI water tank 10 and stored.
A heating means can be installed in the EDI water tank 10 as needed.
The concentrated water generated by the EDI device 10 is discharged from the concentrated water line 33.
The EDI water tank 10 and the RO water tank 6 may be communicated with each other by a communication pipe 34 provided with an on-off valve.

The water storage capacities of the RO water tank 6 and the EDI water tank 10 can be, for example, 100 to 3000 L, respectively. The RO water tank 6 and the EDI water tank 10 are made of metal such as stainless steel.

The shapes of the RO water tank 6 and the EDI water tank 10 are not particularly limited, but from the viewpoint of preventing the liquid from remaining inside the tank and facilitating the flow of the liquid, the bottom is a cone or a quadrangular pyramid. A shaped structure is preferable.

The EDI water tank 10 has a ventilation hole with an air filter to prevent bacteria and the like from entering from the outside atmosphere, and if necessary, an ultraviolet lamp can be attached inside for the purpose of sterilization. ..

The EDI water in the EDI water tank 10 is sent to the UF device 7 by the first intake line 18, and endotoxin, bacteria and the like are removed.
An intake pump (UF device pump) 63 is installed in the first intake line 18.

The purified water treated by the UF device 7 is sent to the artificial dialysate preparation device 50 via the second water intake line 19 and the third water intake line 20 branched from the second water intake line 19.
The second intake line 19 is further connected to the RO water tank 6, and the purified water that has not been taken in is returned to the RO water tank 6.

In the medical purified water production apparatus of the present invention, a combination of a first circulation line, a third circulation line, and a fourth b circulation line that circulates hot water or cooling water when the production operation of the medical purified water is stopped. It has a circulation line consisting of.
The first circulation line is a circulation line that returns from the RO water tank 6 to the RO water tank 6 through the water inlet line 21 (some of which includes the second RO water line 31), the heat exchanger 8, and the water discharge line 22.
The heat exchanger 8 is connected to the first raw water line 11 by a line 24 so that raw water as a cooling medium can be supplied into the heat exchanger 8.
The heat exchanger 8 has a drainage line 25 for raw water used for cooling.
Immediately after the start of cooling operation after the completion of hot water sterilization, the heat exchange water is hot, so a storage pot equipped with a thermometer is provided in the drain line 25, and the raw water is used until the water temperature in the storage pot drops to a predetermined temperature. Drain after mixing and cooling.
Since the drainage (raw water) from the drainage line 25 is tap water or groundwater, it can be used for other purposes.

The third circulation line is from the EDI water tank 10, the intake line 18, the line 23, the raw water supply line 13, the activated carbon device 3, the pretreatment water line 14, the RO device 5, the first RO water line 17, the RO water tank 6, and the third. It is a circulation line that returns to the EDI water tank 10 through the 2RO water line 31, the EDI device 9, and the EDI water line 32.
The 4b circulation line passes through the EDI water tank 10, the first water intake line 18, the UF device 7, the second water intake line 19, the RO water tank 6, the second RO water line 31, the EDI device 9, and the EDI water line 32. It is a circulation line returning to the water tank 10, and EDI water (UF water) flows from the outlet side (upstream side) of the EDI water tank 10 to the inlet side (downstream side) of the RO water tank 6.
A part of the second intake line 19 located near the RO water tank 6 has a bottleneck (flow rate adjusting valve) 78 having a narrower flow path than the other parts, and further sandwiches the bottleneck (flow rate adjusting valve) 78 between them. It has a bypass flow path 26 with an on-off valve 79 that connects the upstream side and the downstream side.
The bottleneck (flow rate adjusting valve) 78 is formed by partially closing the flow path of the flow rate adjusting valve 78 in the embodiment of FIG. Partially closing means that 30 to 70% of the part is closed (70 to 30% is open), assuming that the cross-sectional area of the flow path when the flow rate adjusting valve 78 is opened is 100%. ) Is preferable.
In addition, as shown in FIG. 2, the bottleneck 19a may be formed by reducing the inner diameter of a part of the second intake line 19.

<Sterilization and cooling operation>
When the production operation of purified water by the production apparatus shown in FIG. 2 is continuously carried out, the production operation of purified water is periodically stopped and the sterilization and cooling operations are carried out.

In the manufacturing apparatus shown in FIG. 3, the medical purified water manufacturing operation is performed with the on-off valve 79 of the bypass flow path 26 closed.
The EDI water (UF water) in which the EDI water in the EDI water tank 6 is treated by the UF device 7 is sent from the third water intake line 20 to the artificial dialysate preparation device 50 via the second water intake line 19. The EDI water (UF water) that has not been taken in is returned to the RO water tank 6 through the second water intake line 19 and the 4b circulation line including the bottleneck (flow rate adjusting valve) 78.
Since the fourth b circulation line has a long overall length, the pressure may drop in the middle and it may become difficult to flow. However, in the manufacturing apparatus of FIG. 3, a bottleneck (flow rate adjusting valve) 78 is provided, and the liquid flow of EDI water (UF water) is pressurized so that EDI water (UF water) can easily flow.
The position of the narrow path ( flow control valve) 78 is arranged in the range of 0.5L to 0.99L, where L is the line length from the EDI water outlet at the bottom of the EDI water tank 10 to the RO water inlet of the RO water tank 6. It is preferable that it is arranged in the range of 0.6L to 0.99L, and it is more preferable that it is arranged in the range of 0.6L to 0.99L.
During the production operation of purified medical water, in order to prevent the liquid from staying in the bypass flow path 26, the opening / closing valves 79 are opened at appropriate intervals to allow EDI water (UF water) to pass through the bypass flow path 26. It is preferable to make it watered. For example, after the manufacturing operation for 30 minutes, the opening / closing valve 79 is opened for about 5 to 20 seconds so that EDI water (UF water) can pass through the bypass flow path 26.

The sterilization operation is carried out according to the following procedure.
With the purified water production operation stopped, the RO water in the RO water tank 6 is heated by the heater 6a.
The temperature of RO water before heating is adjusted to 20 to 30 ° C., and is heated by the heater 6a to a temperature of 70 ° C. or higher (preferably about 70 to 100 ° C.), preferably 0.1 to 5 ° C./min. More preferably, the temperature is gradually raised at 0.5 to 4 ° C./min.
The heating temperature is not limited to the above range, and can be appropriately selected and changed depending on the RO membrane module and EDI device used.

The pump 65 is driven to circulate in the first circulation line while heating and raising the temperature of the RO water in the RO water tank 6 at the above-mentioned temperature rising rate.
In parallel with the circulation operation of the first circulation line, the circulation operation of the third circulation line or the fourth a circulation line is performed.
Although the pressurizing pump 62 of the RO device is stopped, the concentrated water circulation pump 64 is operated to pass water to the concentrated water line 16b.
Further, the EDI supply pump 65 is operated at a lower pressure (0.1 MPa at the EDI inlet pressure) than during normal EDI operation to supply heated RO water to the EDI device 9.
Further, in the above heating operation, the opening / closing valve provided in the communication pipe 34 connecting the EDI water tank 10 and the RO water tank 6 is opened to allow the water in both tanks to communicate with each other to heat the inside of the EDI water tank 10. It is also possible to maintain a well-balanced water level in both tanks due to circulation operation.

In addition to the circulation line described above, the sterilization operation using hot water includes the EDI water tank 10, the first intake line 18, the UF device 7, the second intake line 19, the RO water tank 6, the second RO water line 31, and the EDI device 9. This is also carried out for the 4b circulation line that returns to the EDI water tank 10 via the EDI water line 32.
The hot water sterilization operation of the 4b circulation line including the UF device 7 is performed at the same time as the sterilization operation of the first circulation line.
When the sterilization operation of the 4b circulation line is performed, the operation is performed with the on-off valve 79 of the bypass flow path 26 open. When the sterilization operation of the 4b circulation line is performed with the opening / closing valve 79 of the bypass flow path 26 opened in this way, a sufficient amount of hot water can be circulated as compared with the case where the bypass flow path 26 is not provided. Even in the long 4b circulation line, the decrease in hot water temperature is small, which is preferable.
Incidentally, during sterilization operation, the bottleneck (flow regulating valve) 78 by the intact, can also be sterilized bottleneck (flow regulating valve) 78.
Further, by changing the opening degree of the bottleneck (flow rate adjusting valve) 78 in small steps between 0 and 100% during the sterilization operation, it is possible to sterilize every corner of the bottleneck (flow rate adjusting valve) 78.
When performing the sterilization operation of the 4b circulation line, it is also possible to separately carry out the hot water sterilization operation of the second RO water line 31, EDI device 9, and EDI water line 32 after the RO water tank 6.

In this way, the operation of the first circulation line and the operation of the third circulation line and the fourth b circulation line are carried out.
The RO water in the RO water tank 6 is heated evenly by the circulation operation of the first circulation line, and the circulation operation to the third circulation line is carried out while gradually heating and raising the temperature of the RO water.
Therefore, compared to the case where hot water is circulated from the beginning, the thermal load on the equipment (particularly activated carbon, separation membrane, pipe joint, valves) in the third circulation line can be reduced, and finally Since hot water heated to about 70 to 90 ° C. is circulated, sufficient hot water sterilization is also carried out.
In addition, since the third circulation line has a long flow path and the temperature of hot water drops due to heat radiation from piping and equipment, the temperature of hot water as a sterilization medium can be lowered by heating with the line heater 4 as necessary. It is desirable to prevent it. By providing the line heater 4, more precise control of the heating rate and the heating temperature becomes easy. In the present embodiment, it is preferable to provide a bypass flow path 79 instead of the line heater 4.
In the sterilization operation, in order to carry out sufficient sterilization and suppress the thermal effect on the activated carbon and the separation membrane, after the temperature of the hot water passed through the RO device 5 reaches about 70 to 90 ° C. When the temperature of hot water is 70 to 80 ° C., it is preferably circulated for at least 30 minutes, and when the temperature of hot water is 80 to 90 ° C., it is preferably circulated for at least 10 minutes and then stopped.

The cooling operation is carried out according to the following procedure.
After the hot water sterilization operation is completed, the heating in the RO water tank 6 is stopped, then the on-off valve 73 is opened, and raw water is supplied to the heat exchanger 8 as a cooling medium through the line 24.
Then, the RO water is cooled while performing the circulation operation of the first circulation line. The cooling rate at this time can be adjusted by adjusting the flow rate of the flow rate control valve 72 or the like.
The water temperature in the RO water tank 6 is gradually lowered by the circulation operation of the first circulation line, and finally is lowered to about 20 to 30 ° C. The temperature lowering rate is preferably adjusted at 0.1 to 5 ° C./min, more preferably 0.5 to 4 ° C./min.

While lowering the temperature of the RO water in the RO water tank 6 by the circulation operation of the first circulation line described above, the circulation operation of the third circulation line or the 4b circulation line is carried out in parallel with the temperature reduction.
At this time, although the pressurizing pump 62 of the RO device is stopped, the concentrated water circulation pump 64 is operated to pass water to the concentrated water line 16b.

In this way, the circulation operation of the first circulation line and the third circulation line or the fourth b circulation line is carried out in parallel to cool.
Since the RO water is circulated in the third circulation line or the fourth b circulation line while gradually lowering the temperature of the RO water in this way, it is in the third circulation line as compared with the case where cold water (room temperature water) is circulated from the beginning. Thermal effects such as shrinkage due to a sudden temperature drop of the equipment (especially activated carbon, separation membranes and pipe joints, valves) are reduced. In addition, the cooling operation does not require complicated operations such as starting and stopping intermittent water supply when directly supplying and cooling the raw water into the device, and enables a simple and smooth cooling operation.
The cooling operation of the 4b circulation line may be performed at the same time as the cooling operation of the third circulation line, or may be performed separately.
It is desirable that the sterilization operation and the cooling operation using hot water be carried out continuously without interruption.
In addition, the production operation of purified medical water is performed after the completion of hot water sterilization, but the circulation operation of the first circulation line, the third circulation line, and the 4b circulation line (RO) also at night and on holidays when the artificial dialysis treatment is completed. It is preferable to continue the circulation operation of water and / or EDI water in order to prevent the growth of bacteria.

Example 1 and Comparative Example 1
The production operation of purified medical water was carried out using the production apparatus shown in FIG.
The specifications of each device are as follows.

Activated carbon device 3: Duracol MAC750SH manufactured by Daisen Membrane Systems Co., Ltd.
RO device 5: RO membrane module; SV08-GP-DRA heat-resistant RO water tank manufactured by Daisen Membrane Systems Co., Ltd. 6: SUS316, 280L
UF device 7: UF membrane module; FS10FC-FUST653 manufactured by Daisen Membrane Systems Co., Ltd.
RO water tank electric heater 6a: 20kw
Heat exchanger 8: 70000 kcal
RO water production amount: 1000L / hr

After carrying out the production operation of purified medical water using the device of FIG. 1 (without the line heater 4), the operation was stopped, and the sterilization and cooling operations were performed.
The heating of the RO water tank heater 6a was started, and the circulation operation by the two circulation lines of the first circulation line and the second circulation line was carried out in parallel.
The heating by the heater 6a is performed in the RO water tank 6 at 20 to 30 ° C. while controlling the heating rate at the outlet of the RO module 5 of the second circulation line to be 0.5 to 2.5 ° C./min. The water was heated for about 60 minutes until it became hot water at 80 ° C. to 85 ° C.
Then, the circulation operation was continued for 30 minutes while maintaining the hot water temperature of 80 to 85 ° C., and the heat sterilization operation was carried out.

After the completion of the hot water sterilization operation, the cooling operation was continued.
In order to perform the cooling operation, the heating of the RO water tank heater 6a was stopped, then the on-off valve 73 was opened, and raw water was supplied to the heat exchanger 8 as a cooling medium through the cooling water line 24.
The two circulation lines, the first circulation line and the second circulation line, continued the circulation operation in parallel as in the case of the sterilization operation.
For cooling by the heat exchanger 8, hot water at 80 to 85 ° C. is 20 ° C. while controlling the temperature lowering rate at the outlet of the RO module 5 of the second circulation line to be 1.0 to 3.0 ° C./min. It was cooled over about 30 minutes until it reached ~ 30 ° C.

Next, a sterilization operation and a cooling operation with hot water were also carried out on the 4a circulation line (the total length of the line is about 150 m).
In the hot water sterilization operation for the 4a circulation line, the RO water tank heater 6a is started to be heated, the open / close valve 74 is opened, and the first water intake line 18, the UF device 7, the second water intake line 19, and the RO water tank 6 are used. Circulation operation was performed on the circulation line. The on-off valve 79 of the bypass path 26 was fully opened. At this time, the circulation operation of the first circulation line was also performed in parallel.
During the heating operation, the heater 6a controls the temperature rise rate of about 45 to 2.5 ° C./min until the water in the RO water tank 6 at 20 to 30 ° C. reaches 80 ° C. to 85 ° C. It was warmed for a minute.
Then, the circulation operation was continued for 30 minutes while maintaining the hot water temperature of 80 to 85 ° C., and the hot water sterilization operation was carried out. At this time, the temperature of the hot water returned from the second intake line 19 to the RO water tank 6 was about 70 ° C. (return flow rate 600 L / Hr), and the temperature drop was small.
Further, raw water was supplied to the heat exchanger 8 to carry out a cooling operation. The temperature lowering rate was controlled to be 1.0 to 3.0 ° C./min.

The above sterilization operation and cooling operation are performed once a week while performing the purified water production operation, and the purified water production operation is continuously performed for a period of one year or more after the installation of the bypass flow path 26. rice field.
During this operation period, the water in the return water sampling port of the RO tank 6 was sampled regularly (once a month, for the first time in the second week after the installation of the bypass route 26), and the viable cell count was measured. The viable cell count was measured by collecting 200 ml of sample water and using a membrane filter method. The result is shown in FIG.

FIG. 4 shows a device in which the bypass flow path 26 was not installed (Comparative Example 1) at the beginning of the operation, but the bypass flow path 26 was installed 4.5 months after the start of operation (as of October). It shows the change in the viable cell count when operated in (Example 1).
As a result, after installing the bypass flow path 26, a good bactericidal effect could be continuously maintained from 2.5 months onward.
In addition, no troubles such as water leakage due to poor connection of piping, performance deterioration of RO device and UF device, and damage were observed.
Further, it is preferable from the viewpoint that the manufacturing cost is reduced by not using the line heater.

The medical purified water production apparatus of the present invention can be used for producing artificial dialysis water for producing an artificial dialysate, water for an injection solution, and the like.

1 Pre-filter 2 Water softening device 3 Activated carbon device 5 RO device 6 RO water tank 7 UF device 8 Heat exchanger 9 EDI device 10 EDI water tank 26 Bypass path

Claims (6)

Activated carbon adsorption device (hereinafter referred to as "activated carbon device") (3),
Reverse osmosis membrane treatment device (hereinafter referred to as "RO device") (5),
An RO water tank (6) equipped with a heating means (6a) for storing treated water (hereinafter referred to as "RO water") treated by the RO device (5), and
It has a heat exchanger (8) with raw water cooling means connected to the RO water tank (6).
The raw water supply source and the activated carbon device (3) are connected by the raw water supply line (11,12,13).
The activated carbon device (3) and RO device (5) are connected by a pretreatment water line (14).
The RO device (5) and RO water tank (6) are connected by the RO water line (17),
The RO water outlet of the RO water tank (6) is connected to the first end of the first intake line (18), and the second end of the first intake line (18) is the second of the second intake line (19). The first end is branched and connected to the first end of the first return line (23), and the second end of the second intake line (19) is connected to the RO water inlet side of the RO water tank (6). , The second intake line (19) is branched to the third intake line (20) on the way, and the second end of the first return line (23) is connected to the raw water supply line (13).
The RO water tank (6) and the heat exchanger (8) share a part with the first water intake line (18) from the RO water tank (6) to the heat exchanger (8), and the water inlet line (21). A medical purified water production device connected by a water discharge line (22) from the heat exchanger (8) to the RO water tank (6).
It has a circulation line that circulates hot water or cooling water when the production operation of purified medical water is stopped.
The circulation line is a combination of a first circulation line, a second circulation line, and a fourth a circulation line.
The first circulation line is a circulation line that returns from the RO water tank (6) to the RO water tank (6) through the water inlet line (18, 21), the heat exchanger (8), and the water outlet line (22).
The second circulation line is from the RO water tank (6) to the first intake line (18), the first return line (23), the raw water supply line (13), the activated carbon device (3), and the pretreatment water line (14). , RO device (5), RO water line (17) and back to RO water tank (6).
The 4a circulation line is a circulation line that returns from the RO water outlet of the RO water tank (6) to the RO water inlet of the RO water tank (6) through the first intake line (18) and the second intake line (19). Yes, a part of the second intake line (19) located near the RO water tank (6) has a narrow passage that has a narrower flow path than the other parts, and further, the upstream side and the downstream side are sandwiched between the tunnels. Has a bypass flow path with an on-off valve to connect
The first circulation line, the second circulation line, and the fourth a circulation line have the shortest total length of the first circulation line and the longest total length of the fourth a circulation line.
The boundary of the 4a circulation line is in the range of 0.6L to 0.99L, where L is the line length from the RO water outlet of the RO water tank (6) to the RO water inlet of the RO water tank (6). An apparatus for producing purified water for medical use, which is arranged and has a portion of 30 to 70% closed when the cross-sectional area of the flow path before reaching the sluice is 100%. Furthermore, an ultrafiltration membrane device (7) is provided in the water intake line, and the ultrafiltration membrane device (7) and the RO water tank (6) are connected by the first intake line (18) for ultrafiltration. The RO water inlet side of the membrane device (7) and the RO water tank (6) is connected by the second intake line (19).
A part of the second intake line (19) located near the RO water tank (6) has a bottleneck whose flow path is narrower than the other parts, and further connects the upstream side and the downstream side between the bottleneck. The medical purified water production apparatus according to claim 1, which has a bypass flow path with an on-off valve. Activated carbon adsorption device (hereinafter referred to as "activated carbon device") (3),
Reverse osmosis membrane treatment device (hereinafter referred to as "RO device") (5),
An RO water tank (6) equipped with a heating means (6a) for storing treated water (hereinafter referred to as "RO water") treated by the RO device (5), and
It has a heat exchanger (8) with raw water cooling means connected to the RO water tank (6).
The raw water supply source and the activated carbon device (3) are connected by the raw water supply line (11,12,13).
The activated carbon device (3) and RO device (5) are connected by a pretreatment water line (14).
The RO device (5) and RO water tank (6) are connected by the RO water line (17),
The RO water tank (6) and heat exchanger (8) are the water inlet line (21) from the RO water tank (6) to the heat exchanger (8), and the heat exchanger (8) to the RO water tank (6). Connected by the flood line (22) to
In addition, an electroregenerative deionization device (hereinafter referred to as "EDI device") (9) is provided.
The RO water tank (6) and the EDI device (9) are connected by the second RO water line (31).
The EDI device (9) and the EDI water tank (10) for storing the treated water treated by the EDI device (9) (hereinafter referred to as "EDI water") are connected by an EDI water line (32).
A medical purified water production device in which an EDI water tank (10) is connected to an intake line (18).
It has a circulation line that circulates hot water or cooling water when the production operation of purified medical water is stopped.
The circulation line is a combination of a first circulation line, a third circulation line, and a fourth b circulation line.
The first circulation line is a circulation line that returns from the RO water tank (6) to the RO water tank (6) through the water inlet line (21, 31), the heat exchanger (8), and the water outlet line (22).
The third circulation line is from the EDI water tank (10) to the intake line (18), the first return line (23), the raw water supply line (13), the activated carbon device (3), the pretreatment water line (14), and the RO. To EDI water tank (10) through device (5), 1st RO water line (17), RO water tank (6), 2nd RO water line (31), EDI device (9), EDI water line (32) It is a return circulation line,
The 4b circulation line passes from the EDI water outlet of the EDI water tank (10) through the first intake line (18) and the second intake line (19) to the RO water inlet of the RO water tank (6) and the second RO water line. It is a circulation line that returns to the EDI water tank (10) via the (31), EDI device (9), and EDI water line (32), and is the second intake line (19) located near the RO water tank (6). A part has a narrow passage that has a narrower flow path than the other parts, and further has a bypass flow path with an on-off valve that connects the upstream side and the downstream side between the barriers.
The first circulation line, the third circulation line, and the fourthb circulation line have the shortest total length of the first circulation line and the longest total length of the fourthb circulation line.
The bottleneck of the 4b circulation line
When the line length from the EDI water outlet of the EDI water tank (10) to the RO water inlet of the RO water tank (6) is L, it is arranged in the range of 0.6L to 0.99L and reaches the bottleneck. An apparatus for producing purified water for medical use, wherein 30 to 70% of the cross-sectional area of the front flow path is closed. Furthermore, an ultrafiltration membrane device (7) is provided in the water intake line, and the ultrafiltration membrane device (7) and the EDI water tank (10) are connected by the first intake line (18) for ultrafiltration. The RO water inlet side of the membrane device (7) and the RO water tank (6) is connected by the second intake line (19).
A part of the second intake line (19) located near the RO water tank (6) has a bottleneck whose flow path is narrower than the other parts, and further connects the upstream side and the downstream side between the bottleneck. The medical purified water production apparatus according to claim 3, further comprising a bypass flow path with an on-off valve. A method for producing medical purified water by the medical purified water production apparatus according to claim 1.
The method for producing purified medical water includes the operation for producing medical purified water and the operation for sterilization and cooling with the operation for producing medical purified water stopped.
The medical purified water production operation is carried out with the on-off valve of the bypass flow path closed.
The sterilization operation
An operation in which the RO water in the RO water tank is heated by a heating means and circulated to the first circulation line while raising the temperature at 0.1 to 5 ° C./min.
It includes an operation of circulating the RO water to the second circulation line or the fourth a circulation line in parallel with the operation of circulating the RO water to the first circulation line.
When circulating in the 4a circulation line, the opening / closing valve of the bypass flow path is opened to allow the heated RO water to flow through the bypass flow path.
The cooling operation
After stopping the heating by the heating means, the operation of lowering the temperature at 0.1 to 5 ° C./min while circulating the RO water to the first circulation line is performed.
A method for producing medical purified water by a medical purified water producing apparatus, which comprises an operation of circulating the RO water to a second circulation line or a fourth a circulation line in parallel with an operation of circulating the RO water in the first circulation line. A method for producing medical purified water by the medical purified water production apparatus according to claim 3.
The method for producing purified medical water includes the operation for producing medical purified water and the operation for sterilization and cooling with the operation for producing medical purified water stopped.
The medical purified water production operation is carried out with the on-off valve of the bypass flow path closed.
The sterilization operation
An operation in which the RO water in the RO water tank is heated by a heating means to raise the temperature at 0.1 to 5 ° C./min and the RO water is circulated to the first circulation line.
It includes an operation of circulating the RO water to the third circulation line or the fourth b circulation line in parallel with the operation of circulating the RO water to the first circulation line.
When circulating in the 4b circulation line, the opening / closing valve of the bypass flow path is opened to allow the heated RO water to flow through the bypass flow path.
The cooling operation
After stopping the heating by the heating means, the operation of lowering the temperature at 0.1 to 5 ° C./min while circulating the RO water to the first circulation line is performed.
A method for producing medical purified water by a medical purified water production apparatus, which comprises an operation of circulating to a third circulation line or a fourth b circulation line in parallel with an operation of circulating to the first circulation line.

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