KR20210091115A - A method for starting an ultrapure water production apparatus and an ultrapure water production apparatus - Google Patents

Abstract

The present invention aims to shorten the startup period of the pure water production apparatus, and the method for starting the ultrapure water production apparatus of the present invention includes a flow path for flowing target water, and provided on the flow path, wherein the target water is used at a use point. A method for starting up an ultrapure water production apparatus having a water treatment system including at least an ultrafiltration membrane device for water treatment in the previous stage, the step of installing a temporary filter device in a front stage of the ultrafiltration membrane device on the flow path, the temporary filter device after installation, cleaning the water treatment system by starting water supply along the flow path, and separating the temporary filter device from the ultrapure water production device after a predetermined period has elapsed from the start of cleaning by the water supply; will be.

Description

A method for starting an ultrapure water production apparatus and an ultrapure water production apparatus

The present invention relates to a method of starting an ultrapure water production apparatus used when newly installed and started using an ultrapure water production apparatus as an example, and an ultrapure water production apparatus to which the starting method can be applied.

An ultrapure water production apparatus used in a semiconductor manufacturing process, etc., by a water treatment system including a flow path of the target water directed to a use point (place of use), and various treatment devices, treats the target water flowing over the flow path to obtain ultrapure water . This kind of ultrapure water production apparatus mainly includes a primary pure water production unit and a secondary pure water production unit. The primary pure water production unit uses, for example, a pretreatment unit to remove suspended substances in raw water, and a reverse osmosis membrane device or ion exchange device to remove all organic carbon (TOC) components or ion components in the pretreated water. to manufacture On the other hand, the secondary pure water production unit manufactures secondary pure water (ultra pure water) by removing particulates, colloidal substances, organic substances, metals, anions, etc. remaining in the primary pure water.

Here, for example, when the ultrapure water production device is newly installed and started, for example, when assembling the ultrapure water production device at the installation site, the fine particles, live cells, and all organic carbon components in the water treatment system are removed. There are problems such as mixing and elution of metal components from pipes constituting the flow path of the to-be-treated water. Then, as a countermeasure, washing|cleaning the water treatment system in an ultrapure water manufacturing apparatus in advance before normal operation of an ultrapure water manufacturing apparatus is performed (for example, refer patent document 1).

Japanese Laid-Open Patent Publication No. 2004-122020

However, even after continuing the above-mentioned washing|cleaning over a long period of time, the ultrapure water manufactured by the ultrapure water manufacturing apparatus may not meet the desired manufacturing specification. For example, when the connection points of piping in the ultrapure water production apparatus are complicatedly connected, or when there is a problem with the cleanliness of the environment in which the ultrapure water production apparatus is installed, for example, metal particles or sand with a relatively large particle diameter In some cases, the back is present in the water treatment system while being captured by the ultrafiltration membrane device or the like disposed at the front end of the use point. At this time, the elution of components such as metal particles continues for a long period of time in the water treatment system, and as a result, the quality of the produced ultrapure water is continuously deteriorated.

The present invention has been made in order to solve the above problems, and an object of the present invention is to provide a method for starting an ultrapure water production apparatus and an ultrapure water production apparatus which can shorten the startup period of the ultrapure water production apparatus.

The method of starting an ultrapure water production apparatus of the present invention includes a water treatment system comprising at least a flow path for flowing target water, and an ultrafiltration membrane device installed on the flow path to water-treat the target water at the front end of the use point. A method of starting an ultrapure water production device, comprising the steps of: installing a temporary filter device at the front end of the ultrafiltration membrane device on the flow path; and starting water supply along the flow path after installation of the temporary filter device It has the process of washing|cleaning, and the process of isolate|separating the said provisional filter apparatus from the said ultrapure water manufacturing apparatus after a predetermined period has elapsed from the start of the said washing|cleaning by water supply.

The cleaning described above preferably includes a sterilization treatment. In addition, after the step of separating, it is preferable to start water supply along the flow path and perform a step of treating water until ultrapure water meeting the desired production specifications is obtained. In addition, the ultrapure water production device further includes a tank on the upstream side of the temporary filter device on the flow path, and the flow path has a circulation line returning to the tank after passing through the ultrafiltration membrane device, In the washing, it is preferable to circulate the supplied water to the circulation line. In addition, it is preferable that the predetermined period is a period in which the number of circulations calculated from the water quantity and flow rate in the circulation line becomes 0.5 to 2200 times, for example, in accordance with the start of the cleaning.

On the other hand, the ultrapure water production apparatus of the present invention includes a flow path for flowing target water, an ultrafiltration membrane device installed on the flow path to water-treat the target water at the front end of the use point, and the ultrafiltration membrane device on the flow path It is provided at the front end of the filter, and is provided with a filter attachment and detachment mechanism that enables attachment and detachment of the temporary filter device with respect to the flow passage.

It is preferable that the provisional filter apparatus mentioned above is, for example, a microfiltration membrane apparatus. In addition, the flow path is composed of a first pipe, on the other hand, the filter attachment and detachment mechanism once branched from the flow path, while passing through the temporary filter device, a second pipe constituting a branch flow path that joins on the downstream side of the flow path is provided with a plurality of joints removably connected to the first pipe, and a first opening/closing valve provided between a position of the branch in the first pipe and a position of the merging in the first pipe. In addition, on the second pipe, for example, it is preferable that a pair of second on-off valves are provided before and after the temporary filter device, respectively.

ADVANTAGE OF THE INVENTION According to this invention, it is possible to provide the starting method and ultrapure water manufacturing apparatus of the ultrapure water manufacturing apparatus which can shorten the starting period of an ultrapure water manufacturing apparatus.

1 is a block diagram schematically showing the configuration of an ultrapure water production apparatus according to an embodiment of the present invention.
FIG. 2 is a block diagram showing the configuration of a secondary pure water production unit included in the ultrapure water production apparatus of FIG. 1 .
3 is a view showing a state in which the temporary fixed microfiltration membrane device is separated from the secondary pure water production unit of FIG. 2 .
4 is a flowchart showing a method of starting an ultrapure water production apparatus according to an embodiment of the present invention.
FIG. 5 is a diagram illustrating a configuration example in which a circulation line of untreated water is partially different from that of the secondary pure water production unit of FIG. 2 .
6 is a view illustrating another separation state different from the separation state of the microfiltration membrane device of FIG. 3 .

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described based on drawing.

As shown in FIG. 1 , the ultrapure water production apparatus 10 according to the present embodiment is an apparatus for obtaining ultrapure water by water treatment of the untreated water, and includes a pretreatment unit 12 , a primary pure water production unit 14 , and the untreated water. A water treatment system 15 including a flow path 31 , a tank 16 , and a secondary pure water production unit 18 is provided. The pretreatment unit 12 introduces tap water, well water, industrial water, etc. as raw water. The pre-treatment unit 12 has an appropriate configuration according to the quality of raw water, etc., and removes suspended substances from the raw water to generate pre-treated water. The pretreatment part 12 is provided with, for example, a sand filtration device, a microfiltration device, etc., and also has a heat exchanger etc. for adjusting the temperature of to-be-processed water as needed.

The primary pure water production unit 14 removes organic components, ionic components, dissolved gas, etc. in the pretreated water to prepare primary pure water, and supplies it to the primary pure water tank (TK) 16 . The primary pure water production unit 14 includes, for example, a reverse osmosis membrane device, an ion exchange device (a cation exchange device, an anion exchange device, a mixed-bed type ion exchange device, etc.), an ultraviolet oxidation device, and a degassing device (vacuum degassing device, degassing device, etc.) base film device, etc.) by appropriately combining one or more of them. The primary pure water has, for example, a total organic carbon (TOC) concentration of 5 μgC/L or less, and a resistivity of 17 MΩ·cm or more. The tank 16 stores the primary pure water, and supplies the required amount to the secondary pure water production unit 18 .

On the other hand, the secondary pure water manufacturing unit 18 removes impurities in the primary pure water produced by the primary pure water manufacturing unit 14 to manufacture secondary pure water that becomes ultrapure water, and the use point (POU), which is a place of use of ultrapure water. : Point Of Use) (20). The flow path 31 is a flow path for flowing the to-be-treated water, and is water-treated by the pre-treatment unit 12, the primary pure water production unit 14, and the secondary pure water production unit 18 constituting the water treatment system 15. The water to be treated is directed toward the use point 20 . 1 and 2 , the above-described tank 16 is provided on the upstream side of a microfiltration membrane device (temporary filter device) 27 to be described later on the flow path 31 . In addition, the flow path 31 has a circulation line 31b that returns to the tank 16 after passing through the ultrafiltration membrane device 28 described later. Here, in the examples of FIGS. 1 and 2 , the circulation line 31b passes through the tank 16 and the secondary pure water production unit 18 at the position of the use point 20 located at the most downstream, the use point 20 ) to form a return path. That is, the surplus ultrapure water passing through the use point 20 is recovered from the tank 16 through the circulation line 31b of the flow path 31 .

Specifically, as shown in FIGS. 2 and 3 , the secondary pure water production unit 18 includes a circle pump (treated water supply pump) 22 , a heat exchanger (HEX: Heat Exchanger) 23 , UV oxidation Apparatus (TOC-UV) (24), membrane degasifier (MDG) (25), polisher (26), filter detachment mechanism (30), ultrafiltration membrane (UF: Ultrafiltration Membrane) device (28) and particulates A system (29) is provided.

The circle pump 22 is a target water supply pump that supplies the target water (primary pure water) accommodated in the tank 16 to the heat exchanger 23 . The heat exchanger 23 adjusts the temperature of the target water supplied from the circle pump 22 . At this time, it is preferable that the temperature of the water to be treated is controlled to, for example, 25±3° C. by the heat exchanger 23 .

The ultraviolet oxidation device 24 irradiates ultraviolet rays to the water to be treated (primary pure water) whose temperature is controlled by the heat exchanger 23 to decompose and remove trace organic matter in the water to be treated. The ultraviolet oxidation device 24 has, for example, an ultraviolet lamp, and generates ultraviolet rays having a wavelength of around 185 nm. The ultraviolet oxidation device 24 may generate ultraviolet rays having a wavelength of around 254 nm. When ultraviolet rays are irradiated to the water to be treated in the ultraviolet oxidation device 24, the ultraviolet rays decompose water molecules to generate OH radicals, and the OH radicals oxidatively decompose organic substances in the water to be treated.

The membrane degassing device 25 is a device that depressurizes the secondary side of the gas-permeable membrane and allows only the dissolved gas in the water to be treated that flows through the primary side to permeate to the secondary side to remove it. The polisher 26 is a non-regeneration type mixed-bed ion exchange device that has a mixed bed ion exchange resin in which a cation exchange resin and an anion exchange resin are mixed, and adsorbs and removes trace amounts of cation and anion components in the water to be treated.

The filter attachment/detachment mechanism (filter attachment/removal mechanism) 30 to be described later is provided at the front end (immediately before) of the ultrafiltration membrane device 28 on the flow path 31 of the water to be treated, and is connected to the flow path 31 . In contrast, the microfiltration membrane device 27 can be attached and detached. The ultrafiltration membrane device 28 is provided at the front end (immediately before) of the most downstream use point 20 on the flow path 31 .

The ultrafiltration membrane device 28 has a plurality of hollow fiber modules, and the water flow rate per one hollow fiber module is 5 m 3 /h or more. In general, it is 10 m3/h or more. This ultrafiltration membrane device 28 installed on the flow path 31 further treats the water to be treated by the polisher 26 (or the microfiltration membrane device 27 when installed) with water at the front end of the use point 20, For example, microparticles|fine-particles with a particle diameter of 50 nm or more are removed, and ultrapure water (secondary pure water) is obtained.

Here, the ultrapure water (ultrapure water that satisfies the desired water quality condition) in the production specifications in the ultrapure water production apparatus 10 of the present embodiment has a particle size of 50 nm or more and 200 particles/L or less, and the total organic carbon concentration is 1 µgC /L or less, and furthermore, the resistivity is 18 MΩ·cm or more. The particle meter 29 measures the particle diameter of particles in the secondary pure water (ultra-pure water) treated with the ultrafiltration membrane device 28 .

Next, the filter attachment/detachment mechanism 30 and the temporary temporary microfiltration membrane device 27 will be described in detail. The filter attachment/detachment mechanism 30 is provided with the some joint 36, 37, 41, 42 and the on-off valve (1st on-off valve) 33, as shown in FIG.2, FIG.3. On the other hand, the microfiltration membrane (MF: Microfiltration Membrane) device 27 is provided with a membrane having a larger pore diameter than that of the membrane of the ultrafiltration membrane device 28 at the rear stage. Although the pore diameter of this microfiltration membrane is not specifically limited, What has the filtration precision which isolate|separates 0.2 micrometer or more particle|grains is more preferable. This is because, in the present invention, a microfiltration membrane having a relatively large pore diameter is sufficient because the causative agent that inhibits early start-up is relatively large fine particles. In addition, since such a microfiltration membrane substantially reduces the number of membranes and the pressure loss becomes small, good water flow performance is obtained.

As a microfiltration membrane, the thing of a surface layer filtration type may be sufficient, and the thing of a depth filtration (Depth Filtration) type may be sufficient. The latter depth filtration microfiltration membrane is more preferable because it can ensure a large flow rate of water passing through, and thereby uses a small number of membranes and is inexpensive.

In addition, the depth filtration microfiltration membrane is generally used in the front end side of the ultrapure water production device, for example, a guard filter of a reverse osmosis membrane installed in the primary pure water production section, or in the pretreatment section, but as in this embodiment, 2 In the case of application to the tea pure water production unit, it was thought that the removal of fine particles could not be expected because the pore diameter was too large in the depth filtration microfiltration membrane, so it was surprising that it showed an effect at the start.

HDCII series and polyfine II series (manufactured by Pall) for surface-layer filtration microfiltration membranes, and Betafine series (manufactured by 3M Japan), Profile II, Nexis series, and Profile UP series for depth filtration microfiltration membranes (above manufactured by Pall) etc. can be used preferably.

That is, the microfiltration membrane device 27 includes metal particles (foreign substances) desorbed from, for example, piping in the ultrapure water production device 10 , or mixed into the water treatment system 15 in the installation environment of the ultrapure water production device 10 . It becomes possible to capture sand and the like.

The microfiltration membrane device 27 is a temporary (temporary) protection filter device. This microfiltration membrane device 27 is attached to the ultrapure water production device 10 when the ultrapure water production device 10 is newly installed and started, for example, but after the start of the ultrapure water production device is completed, the ultrapure water production device 10 is installed. ) is removed (removed) through the filter removal mechanism 30 in the.

Here, the flow path 31 of the to-be-processed water is comprised by the piping 31a. In addition, in order to temporarily set the microfiltration membrane device 27 as a temporary station, a branch flow path 32 that branches off from the flow path 31 and joins on the downstream side of the flow path 31 while passing through the microfiltration membrane device 27 is constituted. The piping (2nd piping) 32a for carrying out is prepared. That is, the microfiltration membrane device 27 is interposed in the middle of the pipe 32a.

2 and 3 , the joints 41 and 42 connect the pipe 32a to the pipe 31a so that it can be removed. Further, the joints 36 and 37 also connect the pipe 32a to the pipe 31a in a removable manner. Specifically, the joints 36 and 37 together with the on-off valves 34 and 35 enable the pipe 32a to be removed from the pipe 31a. In this embodiment, as shown in FIG. 3, the aspect which removes the pipe|tube 32a and the provisional microfiltration membrane device 27 from the pipe|tube 31a mainly through the joints 41 and 42 is illustrated.

The opening/closing valve 33 is provided between the branching position and the merging position in the pipe 31a, and switches the water passing through the pipe 31a and shutting off (non-passing). In addition, on the pipe 32a, a pair of on-off valves (second on-off valves) 34 and 35 are provided before and after the temporary temporary microfiltration membrane device 27, respectively. The opening/closing valve 35 switches the water passing through the pipe 32a and shutting off (no water passing).

Therefore, as shown in Fig. 2, for example, in a state where the microfiltration membrane device 27 is installed, it branches once from the flow path 31 and passes through the branch flow path 32 and the microfiltration membrane device 27 to the flow path ( 31), the on-off valve 33 is closed, while the on-off valves 34 and 35 are opened when water is transmitted and received from the path where it joins on the downstream side. In addition, as shown in FIG. 3, the state in which the microfiltration membrane device 27 is separated (removed) from the ultrapure water production apparatus 10, and the state in which the microfiltration membrane device 27 is installed as shown in FIG. In the case where water is supplied to the flow path 31 in a path that does not pass through the branch flow path 32 and the microfiltration membrane device 27 including, the opening/closing valve 33 is opened while the opening/closing valves 34 and 35 are closed.

In addition, in this case, the section from the joint 36 to the on-off valve 34 and the section from the on-off valve 35 to the joint 37 become a dead space, and we are concerned about water quality deterioration due to the retention of water. So, after removing the temporary microfiltration membrane device 27 together with the pipe 32a, a narrow pipe is installed instead of the separated pipe 32a, and a small flow rate flows from the joint 36 to the joint 37. It is also possible to prevent the retention of water.

Next, a method for starting up the ultrapure water production apparatus 10 according to the present embodiment (a method for producing ultrapure water by the ultrapure water production apparatus 10) is explained in addition to FIGS. 1 to 3, based on the flowchart shown in FIG. 4 . do. When the ultrapure water production apparatus 10 is started, first, in addition to the attachment of the polisher 26, the ultrafiltration membrane apparatus 28, the flow path 31 (pipe 31a), etc., the filter attachment/detachment mechanism 30 is As shown in Figs. 2 and 4, a temporary temporary microfiltration membrane device 27 is installed (attached) on the main body of the ultrapure water production device 10 (S1).

After installation of the microfiltration membrane device 27, the on-off valve 33 on the pipe 31a is closed, while the on-off valves 34 and 35 on the pipe 32a (branch flow path 32) are opened. After this installation of the microfiltration membrane device 27, for example, by starting the water supply along the flow path 31 including the branch flow path 32 and the circulation line 31b at the front end of the pretreatment part 12, FIG. , as shown in Figs. 2 and 4, each device in the pretreatment unit 12, the primary pure water production unit 14, the above-described flow path 31, the polisher 26, the ultrafiltration membrane device 28, etc. to wash the water treatment system 15 (S2). At this time, the microfiltration membrane device 27 traps metal particles in the ultrapure water production device 10 , for example, desorbed from the piping, sand mixed with the water treatment system 15 , and the like.

In the above-mentioned washing, the water for water supply (washing water) for washing the water treatment system 15 is preferably primary pure water. In addition, in this washing, according to the start of the washing, the water (washing water) for washing that has passed through the position of the use point 20 returns to the position of the use point 20 at least once around the circulation line 31b. It will be carried out over a certain period of time.

The number of cycles calculated from the water quantity and flow rate in the circulation line 31b according to the start of the cleaning is preferably 0.5 to 2200 times, more preferably 1 to 1000 times, and still more preferably 40 to 500 times. Moreover, 0.25 hours - 1000 hours are preferable, as for water passing time, 0.5 hours - 720 hours are more preferable, and 24 hours - 170 hours are still more preferable. Moreover, since many foreign substances are contained in the front end side of a circulation system, although an effect is acquired even if the number of circulation is 0.5 times, the effect becomes large when it exceeds one time.

When the number of circulations or the water passing time is small, the microfiltration membrane cannot sufficiently replenish foreign substances, so that the effect of shortening the start-up time is not obtained. On the other hand, when the number of circulations or the water passing time is large, the effect of shortening the startup time is not obtained because foreign substances captured by the microfiltration membrane are crushed and flowed out to the rear stage, for example. In addition, the most suitable conditions differ depending on the length or diameter of the installed pipe, the number of branches, etc., so that the conditions are appropriately selected within the above range and cleaning is performed.

Here, the predetermined period may be, for example, one week. In addition, each device in the pre-processing part 12, the primary pure water manufacturing part 14, and the secondary pure water manufacturing part 18 will be in an operating state about during washing|cleaning. By washing as described above, the fine filtration membrane device 27 captures, for example, metal particles and the like desorbed from the pipe flow in the ultrapure water production device 10 .

After a predetermined period has elapsed from the start of washing (YES in S3), the microfiltration membrane device 27 that has captured metal particles and the like is removed (separated) from the ultrapure water production device 10 (S4). Specifically, after stopping water supply, the on-off valves 34 and 35 on the pipe 32a (branch flow path 32) are closed. Moreover, as shown in FIG. 3, the temporary installation microfiltration membrane device 27 is removed together with the piping 32a through the joints 41 and 42.

After removing the microfiltration membrane device 27, the on/off valve 33 is opened, and each device in the pretreatment section 12, the primary pure water production section 14 and the secondary pure water production section 18 is operated. , and the water supply (supply of raw water to the pretreatment unit 12) along the flow path 31 including the circulation line 31b is started, and water treatment by the water treatment system 15 is performed (S5) . Moreover, it is also possible to perform washing|cleaning without stopping the water supply between the operation of the step S4 of removing and the step S5 of performing water treatment. In this case, the on-off valve 33 is opened and the on-off valves 34 and 35 are closed at the same time or thereafter. Then, the microfiltration membrane device 27 may be removed. This water treatment is continued until it is possible to obtain ultrapure water meeting the desired manufacturing specification exemplified above (until the quality of the ultrapure water is within the specification) (S6). At this time, whether or not the particle diameter of the particle|grains in secondary pure water (ultra-pure water) is within the manufacturing specification is measured by the particle meter 29. After that, when the ultrapure water meeting the production specification is obtained (YES in S6), the startup of the ultrapure water production apparatus 10 is completed (S7).

Here, in the starting method of the ultrapure water production apparatus 10 of the present embodiment, the water treatment system 15 is washed in a state where the microfiltration membrane device 27 is installed in the front stage (just before) of the ultrafiltration membrane device 28, After a predetermined period has elapsed, for example, the microfiltration membrane device 27 that has captured metal particles, sand, etc. is removed (separated) from the ultrapure water production device 10, and then water treatment is performed. It is possible to remove the above-mentioned metal particles, sand, etc. from the inside. Therefore, according to the starting method of the ultrapure water production apparatus 10 of the present embodiment, it may exist in the water treatment system 15, for example, the elution of sand or metal particle components continues, and the water quality of the ultrapure water is reduced. It is possible to avoid being in a stagnant state or the like. That is, in the water treatment after the removal of the microfiltration membrane device 27 , ultrapure water meeting the desired production specifications is obtained promptly, whereby the startup period of the ultrapure water production device 10 can be shortened.

In addition, it is possible to perform a sterilization operation in the secondary pure water production unit 18 using hydrogen peroxide or the like at any stage of this operation. In this case, a line (not shown) bypassing the polisher 26 and/or the ultrafiltration membrane device 28 is used to connect the polisher 26 and/or the ultrafiltration membrane device 28 (water treatment system ( 15)), and hydrogen peroxide is added into the system using any of the secondary pure water production units 18, for example, a branch valve installed on the suction side of the tank 16 or the pump 22. After that, a predetermined time cycle is performed. After sufficient sterilization treatment has been performed, the hydrogen peroxide is drained from a place. After the hydrogen peroxide in the system is eliminated, bypassing of the polisher 26 and/or the ultrafiltration membrane device 28 is stopped.

Further, in the starting method of the ultrapure water production apparatus of the present invention, the water treatment system 15 including the polisher 26 is cleaned in a state in which the ion exchange resin is not filled in the body of the polisher 26, and at a certain stage The cleaning operation may be stopped and the body of the polisher 26 may be filled with an ion exchange resin.

In addition, although the above operation was demonstrated by applying the circulation line 31b containing the use point 20, as shown in FIG. 5, it is also possible to use the circulation line 31c which bypassed the use point 20. do. In this case, an operation is performed to include the use point 20 in the circulation line at a certain stage. In addition, in order to further shorten the starting time, it is preferable to select the starting method in the circulation line 31b including the use point 20 .

In addition, in order to supplement the water supply by the circle pump 22, you may provide the booster pump 43 between the polisher 26 and the joint 36, as shown in FIG. Such a booster pump 43 can also be added to the secondary pure water production unit illustrated in FIGS. 2 and 3 or the secondary pure water production unit shown in FIG. 6 to be described later.

On the other hand, after washing with washing water using an ultrapure water production apparatus not equipped with a temporary filter device (fine filtration membrane device 27) as described above with respect to the device configuration of the ultrapure water production apparatus 10, water treatment is performed In the case of implementation, it has been verified that ultrapure water meeting the manufacturing specifications cannot be obtained even if such washing and water treatment are continued, for example, for a period of 4 months. In this case, metal powder, sand, etc. are trapped in the hollow fiber module in the ultrafiltration membrane device 28, and the captured foreign material is crushed over time and leaked out at the rear end. didn't Therefore, by exchanging all the hollow fiber modules in the ultrafiltration membrane device 28 with new ones and performing water treatment again, ultrapure water meeting the manufacturing specifications was finally obtained.

In addition, when washing with washing water and water treatment are also performed while the microfiltration membrane device 27 is mounted using the ultrapure water manufacturing device having the same device configuration as the ultrapure water manufacturing device 10, such washing and water treatment are performed, for example, , it has been verified that ultrapure water that meets the manufacturing specifications cannot be obtained even if continued for 3 months. In this case, for example, metal powder or sand of a size that can be observed with the naked eye is captured in the microfiltration membrane device 27, and after the microfiltration membrane device 27 is removed, water treatment is performed again, so that ultrapure water barely meeting the manufacturing specifications. has been obtained

On the other hand, according to the starting method of the ultrapure water production apparatus 10 of this embodiment, after cleaning using a cleaning liquid containing hydrogen peroxide in a state where the microfiltration membrane device 27 is installed for one week, the ultrapure water production apparatus 10 For example, it has been verified that ultrapure water meeting production specifications can be obtained immediately by performing water treatment after removing the microfiltration membrane device 27 that has captured metal particles, sand, and the like.

As already described, according to the starting method of the ultrapure water production apparatus 10 of the present embodiment (and the ultrapure water production apparatus 10 to which this starting method is applicable), a temporary filter device (fine filtration membrane device 27) and By carrying out the washing|cleaning and water treatment which utilized the filter attachment/detachment mechanism 30 effectively, shortening of the start-up period of the ultrapure water manufacturing apparatus 10 can be aimed at. In addition, instead of the filter attachment/detachment mechanism 30 shown in FIG. 3, as shown in FIG. 6, it is also possible to apply the filter attachment/detachment mechanism 40 to an ultrapure water manufacturing apparatus and its starting method. In the case of this filter attachment/detachment mechanism 40, after closing the on-off valves 34 and 35, the on-off valves 34 and 35 through the joints 36 and 37 together with the piping 32 (branch flow path 32a) and The microfiltration membrane device 27 is removed (separated). After removing the temporary temporary microfiltration membrane device 27 together with the on/off valves 34 and 35 and the pipe 32a from the ultrapure water production device 10, the part where the pipe 32a was installed at the joints 36 and 37 In this case, for example, blocking plugs (stop stoppers) 38 and 39 are mounted.

As mentioned above, although this invention was demonstrated concretely by embodiment, this invention is not limited as it is this embodiment, In an implementation stage, various changes are possible in the range which does not deviate from the summary. For example, some components may be deleted from all the components shown in the embodiment, and it is also possible to appropriately combine a plurality of components disclosed in the above embodiments.

10… Ultrapure water production device, 12… preprocessor, 14... Primary pure water production unit, 15 ... Water treatment system, 16... Tank (TK), 18… Secondary pure water production unit, 20... Use Point (POU), 22… Circle pump, 23… Heat exchanger (HEX), 24… Ultraviolet Oxidizer (TOC-UV), 25… Membrane degassing device (MDG), 26... Polisher, 27... Microfiltration membrane device (MF), 28... Ultrafiltration Membrane Device (UF), 29... Particulate system, 30, 40... A filter attachment and detachment mechanism, 31... Euro, 31a... Piping (first pipe), 31b, 31c... Circulation line, 32... Quarterly Euro, 32a… pipe (second pipe), 33... an on-off valve (first on-off valve), 35... On-off valve (second on-off valve), 36, 37, 41, 42... joint, 38, 39... occlusion plug.

Claims (13)

A method of starting an ultrapure water production apparatus having a water treatment system comprising at least a flow path for flowing target water;
A step of installing a temporary filter device in front of the ultrafiltration membrane device on the flow path;
a step of cleaning the water treatment system by starting water supply along the flow path after installation of the temporary filter device;
and a step of separating the provisional filter device from the ultrapure water production device after a predetermined period has elapsed from the start of the washing by the water supply. The method of claim 1,
The said washing|cleaning includes the sterilization process, The starting method of the ultrapure water manufacturing apparatus. 3. The method according to claim 1 or 2,
The starting method of the ultrapure water manufacturing apparatus which further has the process of starting water supply along the said flow path after the said separating process, and performing water treatment until the ultrapure water which meets the desired manufacturing specification is obtained. 4. The method according to any one of claims 1 to 3,
The ultrapure water production device further includes a tank on the upstream side of the temporary filter device on the flow path,
the flow passage has a circulation line returning to the tank after passing through the ultrafiltration membrane device;
In the washing, the starting method of the ultrapure water production apparatus, wherein the supplied water is circulated in the circulation line. 5. The method of claim 4,
The method of starting the ultrapure water production apparatus, wherein the predetermined period is a period in which the number of circulations calculated from the water quantity and flow rate in the circulation line becomes 0.5 to 2200 times according to the start of the washing. 6. The method according to any one of claims 1 to 5,
The temporary filter device has a filtration precision for separating particles of 0.2 μm or more, the starting method of the ultrapure water production device. 7. The method according to any one of claims 1 to 6,
The ultrafiltration membrane device has a plurality of hollow fiber modules,
The water flow rate per one hollow fiber module is 10 m 3 /h or more, the starting method of the ultrapure water production apparatus. 8. The method according to any one of claims 1 to 7,
A method of starting an ultrapure water production apparatus, wherein the ultrapure water meeting the desired production specifications has a particle size of 50 nm or more and 200 particles/L or less. a flow path for flowing the water to be treated;
an ultrafiltration membrane device that is installed on the flow path and treats the water to be treated with water at the front end of the use point;
and a filter attachment/detachment mechanism provided at the front end of the ultrafiltration membrane device on the flow path, and enabling attachment and detachment of the temporary filter device from the flow path. 10. The method of claim 9,
The provisional filter device is a microfiltration membrane device, ultrapure water production device. 11. The method of claim 9 or 10,
The flow path is composed of a first pipe,
The filter removal mechanism is
A plurality of joints for removably connecting a second pipe constituting a branching flow path that branches off from the flow path and merges on a downstream side of the flow path while passing through the temporary filter device with respect to the first pipe;
and a first on-off valve provided between the branching position and the merging position in the first pipe. 12. The method of claim 11,
A pair of second on-off valves are installed on the second pipe before and after the temporary filter device, respectively. 13. The method according to any one of claims 9 to 12,
A tank is further provided on the upstream side of the temporary filter device on the flow path,
and the flow path has a circulation line returning to the tank after passing through the ultrafiltration membrane device.

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