JP7171386B2 - Method for starting up ultrapure water production device and ultrapure water production device - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for starting up an ultrapure water production apparatus, which is used, for example, when a new ultrapure water production apparatus is installed and started up, and an ultrapure water production apparatus to which this startup method can be applied.

Ultrapure water production equipment used in the semiconductor manufacturing process, etc., uses a water treatment system that includes a flow path for the water to be treated that is directed to the point of use (place of use). Get pure water. This type of ultrapure water production system mainly includes a primary pure water producing section and a secondary pure water producing section. The primary pure water production unit includes, for example, a pretreatment unit that removes suspended solids in the raw water, and a reverse osmosis membrane device or an ion exchange device that removes total organic carbon (TOC) components and ion components in the pretreated water. to produce primary pure water. On the other hand, the secondary pure water production section produces secondary pure water (ultra-pure water) by removing fine particles, colloidal substances, organic substances, metals, anions, etc. remaining in the primary pure water.

Here, for example, in order to newly install and start up an ultrapure water production apparatus, for example, when assembling the ultrapure water production apparatus at the installation site, fine particles, viable bacteria, There are problems such as contamination of all organic carbon components and elution of metal components from pipes forming the flow path of the water to be treated. Therefore, as a countermeasure, prior to the normal operation of the ultrapure water production apparatus, the water treatment system in the ultrapure water production apparatus is washed in advance (see, for example, Patent Document 1).

Japanese Patent Application Laid-Open No. 2004-122020

However, even after the above-described cleaning is continued for a long period of time, there are cases where the ultrapure water produced by the ultrapure water production apparatus does not fall within the expected production specifications. For example, if the connection points of pipes in the ultrapure water production equipment are complicatedly connected, or if there is a problem with the cleanliness of the environment where the ultrapure water production equipment is installed, Large metal particles, sand, etc. may exist in the water treatment system in a state of being captured by an ultrafiltration membrane device or the like placed upstream of the point of use. At this time, elution of components such as metal particles continues for a long period of time in the water treatment system, and as a result, the water quality of the produced ultrapure water continuously deteriorates.

The present invention has been made to solve the above problems, and provides a method for starting up an ultrapure water production apparatus and an ultrapure water production apparatus capable of shortening the startup period of the ultrapure water production apparatus. for the purpose.

A method for starting up an ultrapure water production apparatus of the present invention includes a flow path for flowing water to be treated, and an ultrafiltration membrane device provided on the flow path for treating the water to be treated before the point of use. and a method for starting up an ultrapure water production system comprising a water treatment system comprising at least a step of installing a temporarily placed filter device upstream 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 installing the temporarily placed filter device; from the ultrapure water production apparatus.

The cleaning described above includes sterilization. Further, after the separating step, water treatment is carried out until ultrapure water within the desired manufacturing specifications is obtained by starting water supply along the flow path. Further, the ultrapure water production apparatus further includes a tank on the upstream side of the temporarily placed filter device on the flow path. Moreover, the flow path has a circulation line returning to the tank after passing through the ultrafiltration membrane device. Further, it is preferable that the predetermined period is a period in which the number of times of circulation calculated from the amount and flow rate of water in the circulation line is, for example, 0.5 to 2200 times when the cleaning is started.

On the other hand, the ultrapure water production apparatus of the present invention includes a flow path for flowing water to be treated, an ultrafiltration membrane device provided on the flow path, and performing water treatment on the water to be treated before the point of use, a filter attachment/detachment mechanism that is provided on the flow path before the ultrafiltration membrane device and that enables attachment and detachment of a temporarily placed filter device to the flow path.

The temporary filter device described above is, for example, a microfiltration membrane device. Moreover, the said flow path is comprised by the 1st piping. On the other hand, the filter attachment/detachment mechanism connects a second pipe that forms a branched flow path that once branches from the flow path and merges on the downstream side of the flow path via the temporarily placed filter device to the first pipe. and a first on-off valve provided between the branch position and the confluence position in the first pipe. Further, on the second pipe, for example, a pair of second on-off valves and the like are provided before and after the temporarily placed filter device.

According to the present invention, it is possible to provide a method for starting up an ultrapure water production apparatus and an ultrapure water production apparatus capable of shortening the startup period of the ultrapure water production 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. FIG. 2 is a block diagram showing the configuration of a secondary pure water production unit provided in the ultrapure water production apparatus of FIG. 1; FIG. 3 is a diagram showing a state in which a temporarily placed microfiltration membrane device is separated from the secondary pure water production unit in FIG. 2 ; 4 is a flow chart showing a method for starting up the ultrapure water production apparatus according to the embodiment of the present invention. The figure which showed the structural example which the circulation line of to-be-processed water partially differs from the secondary pure water production part of FIG. FIG. 4 is a view exemplifying another separation state different from the separation state of the microfiltration membrane device of FIG. 3 ;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described based on the drawings.
As shown in FIG. 1, an ultrapure water production apparatus 10 according to the present embodiment is an apparatus for obtaining ultrapure water by treating water to be treated, and includes a pretreatment unit 12, a primary pure water production unit 14, A water treatment system 15 including a flow path 31 for water to be treated, a tank 16 and a secondary pure water production unit 18 is provided. The pretreatment unit 12 introduces city water, well water, industrial water, or the like as raw water. The pretreatment unit 12 has an appropriate configuration according to the quality of the raw water, etc., and removes suspended solids from the raw water to generate pretreated water. The pretreatment unit 12 includes, for example, a sand filter device, a microfiltration device, and the like, and further has a heat exchanger and the like for adjusting the temperature of the water to be treated as necessary.

The primary pure water production unit 14 removes organic components, ion components, dissolved gases, etc. from the pretreated water to produce primary pure water, and supplies this primary pure water to the tank (TK) 16 . The primary pure water production unit 14 includes, for example, a reverse osmosis membrane device, an ion exchange device (cation exchange device, anion exchange device, mixed bed ion exchange device, etc.), an ultraviolet oxidation device, and a degassing device (vacuum degassing device, degassing membrane device, etc.). 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 primary pure water and supplies the required amount to the secondary pure water producing section 18 .

On the other hand, the secondary pure water production unit 18 removes impurities from the primary pure water produced by the primary pure water production unit 14 to produce secondary pure water that becomes ultrapure water, is supplied to a point of use (POU) 20 . The flow path 31 is a flow path for flowing the water to be treated, and the water to be treated by the pretreatment unit 12, the primary pure water production unit 14, and the secondary pure water production unit 18, which constitute the water treatment system 15. Direct the treated water to the point of use 20. Further, as shown in FIGS. 1 and 2, the tank 16 described above is provided upstream of a microfiltration membrane device (temporary filter device) 27 described later on the flow path 31 . Further, 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 extends from the position of the point of use 20 located most downstream to the position of the point of use 20 via the tank 16 and the secondary pure water production unit 18. Constructing a return route. That is, the surplus ultrapure water that has passed through the point of use 20 passes through the circulation line 31 b of the flow path 31 and is collected in the tank 16 .

Specifically, as shown in FIGS. 2 and 3, the secondary pure water production unit 18 includes a circle pump (water supply pump to be treated) 22, a heat exchanger (HEX) 23, an ultraviolet oxidation device ( TOC-UV) 24 , membrane degasifier (MDG) 25 , polisher 26 , filter attachment/detachment mechanism 30 , ultrafiltration membrane (UF) device 28 , and particle counter 29 .

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

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

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

A filter attachment/detachment mechanism (filter attachment/removal mechanism) 30, which will be described in detail later, is provided in the front stage (immediately) of the ultrafiltration membrane device 28 on the flow path 31 of the water to be treated. to enable attachment and detachment of the microfiltration membrane device 27 . The ultrafiltration membrane device 28 is provided in the front stage (immediately before) the most downstream point of use 20 on the channel 31 .

The ultrafiltration membrane device 28 has a plurality of hollow fiber modules, and the water flow rate per hollow fiber module is 5 m ³ /h or more. Generally, it is 10 m ³ /h or more. The ultrafiltration membrane device 28 provided on the flow path 31 further treats the water to be treated by the polisher 26 (or the microfiltration membrane device 27 when attached) at the front stage of the point of use 20, for example Ultrapure water (secondary pure water) is obtained by removing fine particles having a particle size of 50 nm or more.

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

Next, the filter attaching/detaching mechanism 30 and the temporarily placed microfiltration membrane device 27 will be described in detail. The filter attachment/detachment mechanism 30 includes a plurality of joints 36, 37, 41, and 42 and an on-off valve (first on-off valve) 33, as shown in FIGS. On the other hand, the microfiltration membrane (MF) device 27 has a membrane with a pore size larger than that of the ultrafiltration membrane device 28 in the subsequent stage. Although the pore size of the microfiltration membrane is not particularly limited, it is more preferable that the microfiltration membrane has a filtration accuracy to separate particles of 0.2 μm or more. This is because, in the present invention, the causative substances that inhibit the early start-up are relatively large fine particles, so a microfiltration membrane with a relatively large pore size is sufficient. Furthermore, such a microfiltration membrane has a substantially reduced number of membranes and a small pressure loss, so that good water permeability can be obtained.

The microfiltration membrane may be of a surface layer filtration type or a depth filtration type. The latter depth filtration type microfiltration membrane is more preferable because it can secure a large flow rate of water flow, thereby reducing the number of membranes to be used and being inexpensive.

In addition, the depth filtration type microfiltration membrane is generally used in the upstream side of the ultrapure water production apparatus, for example, the guard filter of the reverse osmosis membrane installed in the primary pure water production unit, or in the pretreatment unit. However, when trying to apply it to the secondary pure water production part like this embodiment, the pore size of the depth filtration type microfiltration membrane is too large, so we thought that removal of fine particles could not be expected. It was unexpected to show the effect in .

Surface filtration type microfiltration membranes include the HDCII series and Polyfine II series (manufactured by Pall). Profile UP series (manufactured by Pall) and the like can be preferably used.

In other words, the microfiltration membrane device 27 contains metal particles (foreign matter) detached from, for example, piping in the ultrapure water production device 10, and mixed into the water treatment system 15 from the installation environment of the ultrapure water production device 10. It is possible to capture sand and the like.

The microfiltration membrane device 27 is a temporary (temporary) protective filter (Temporary Guard 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 up, for example, but after the startup of the ultrapure water production device is completed is removed (removed) from the ultrapure water production apparatus 10 via the filter attachment/detachment mechanism 30 .

Here, the flow path 31 for the water to be treated is configured by a pipe 31a. Also, in order to temporarily place the microfiltration membrane device 27, a branch flow path 32 that once branches from the flow path 31 and merges on the downstream side of the flow path 31 via the microfiltration membrane device 27 is provided. A pipe (second pipe) 32a is prepared. That is, the microfiltration membrane device 27 is interposed in the middle of the pipe 32a.

As shown in FIGS. 2 and 3, joints 41 and 42 detachably connect pipe 32a to pipe 31a. Joints 36 and 37 also detachably connect the pipe 32a to the pipe 31a. Specifically, the joints 36 and 37 allow the pipe 32a to be detached from the pipe 31a together with the on-off valves 34 and 35. As shown in FIG. In the present embodiment, as shown in FIG. 3, a mode of removing the pipe 32a and the temporarily placed microfiltration membrane device 27 from the pipe 31a mainly through the joints 41 and 42 will be exemplified.

The on-off valve 33 is provided between the branch position and the confluence position in the pipe 31a, and switches between water flow and cutoff (non-flow) to the pipe 31a. A pair of on-off valves (second on-off valves) 34 and 35 are provided on the pipe 32a before and after the temporarily placed microfiltration membrane device 27, respectively. The on-off valves 34 and 35 switch between passing water and blocking (not passing water) to the inside of the pipe 32a.

Therefore, as shown in FIG. 2, for example, in a state where the microfiltration membrane device 27 is installed, once branched from the flow channel 31 and passed through the branch flow channel 32 and the microfiltration membrane device 27, on the downstream side of the flow channel 31 When water is fed through a confluence route, the on-off valve 33 is closed, while the on-off valves 34 and 35 are opened. In addition, as shown in FIG. 3, the microfiltration membrane device 27 is separated (removed) from the ultrapure water production apparatus 10, and as shown in FIG. 2, the microfiltration membrane device 27 is installed. When water is sent to the channel 31 through a route that does not pass through the branch channel 32 and the microfiltration membrane device 27, the on-off valve 33 is opened, while the on-off valves 34 and 35 are closed.

Next, a method for starting up the ultrapure water production apparatus 10 according to the present embodiment (method for producing ultrapure water by the ultrapure water production apparatus 10) will be described based on the flowchart shown in FIG. 4 in addition to FIGS. explain. When starting up the ultrapure water production device 10, first, in addition to assembling the polisher 26, the ultrafiltration membrane device 28, the flow path 31 (piping 31a), etc. As shown, the temporary microfiltration membrane device 27 is installed (assembled) in the main body of the ultrapure water production device 10 (S1).

After the microfiltration membrane device 27 is installed, 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 such installation of the microfiltration membrane device 27, for example, by starting water supply from the front stage of the pretreatment unit 12 along the flow path 31 including the branch flow path 32 and the circulation line 31b, FIGS. As shown in FIG. 4, the water treatment system 15 including the pretreatment unit 12, each device in the primary pure water production unit 14, the flow path 31 described above, the polisher 26, the ultrafiltration membrane device 28, etc. is washed (S2 ). At this time, the microfiltration membrane device 27 captures metal particles detached from, for example, piping in the ultrapure water production apparatus 10 and sand mixed in the water treatment system 15 .

In the cleaning described above, the water (cleaning water) for cleaning the water treatment system 15 is preferably primary pure water. In addition, in such washing, when the washing is started, the water for washing (washing water) that has passed through the position of the point of use 20 at least circulates through the circulation line 31b to the position of the point of use 20. It is implemented for a predetermined period of time or longer.

With the start of washing, the number of circulations calculated from the amount and flow rate of water in the circulation line 31b is preferably 0.5 to 2200 times, more preferably 1 to 1000 times, and even more preferably 40 to 500 times. Also, the water flow time is preferably 0.25 hours to 1000 hours, more preferably 0.5 hours to 720 hours, and even more preferably 24 hours to 170 hours. In addition, since many foreign matters are contained in the front stage of the circulation system, the effect can be obtained even if the number of times of circulation is 0.5, but the effect becomes large when the number of times exceeds 1.

If the number of times of circulation or the water flow time is small, the microfiltration membrane cannot sufficiently trap foreign matter, so the effect of shortening the start-up time cannot be obtained. On the other hand, if the number of times of circulation or the water flow time is large, the foreign matter captured by the microfiltration membrane is pulverized and flows out to the subsequent stage, so that the effect of shortening the start-up time cannot be obtained. Although the most suitable conditions differ depending on the length and diameter of the installed pipe, the number of branches, etc., washing is carried out by appropriately selecting the conditions within the above range.

Here, the predetermined period may be, for example, one week. During cleaning, each device in the pretreatment unit 12, the primary pure water production unit 14, and the secondary pure water production unit 18 is in operation. Due to the washing as described above, the microfiltration membrane device 27 captures metal particles and the like detached from, for example, pipes in the ultrapure water production device 10 .

After a predetermined period of time has elapsed from the start of cleaning (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 the water supply, the on-off valves 34 and 35 on the pipe 32a (the branch flow path 32) are closed. Further, as shown in FIG. 3, the temporarily placed microfiltration membrane device 27 is removed together with the pipe 32a via the joints 41 and 42 .

After removing the microfiltration membrane device 27, the on-off valve 33 is opened, each device in the pretreatment unit 12, the primary pure water production unit 14, and the secondary pure water production unit 18 is put into operation, and the circulation line 31b is closed. The water supply (supply of raw water to the pretreatment unit 12) along the flow path 31 is started, and water treatment is performed by the water treatment system 15 (S5). It is also possible to perform washing without stopping water supply between the step of removing (S4) and the step of water treatment (S5). In that case, the on-off valve 33 is opened, and the on-off valves 34 and 35 are closed at the same time or after that. Then, the microfiltration membrane device 27 may be removed. This water treatment is continued until ultrapure water within the desired manufacturing specifications exemplified above is obtained (the quality of the ultrapure water meets the specifications) (S6). At this time, the particle size counter 29 measures whether the particle size of the particles in the secondary pure water (ultra-pure water) is within the manufacturing specifications. After that, when ultrapure water within the manufacturing specifications is obtained (YES in S6), startup of the ultrapure water production apparatus 10 is completed (S7).

Here, in the method for starting up the ultrapure water production apparatus 10 of the present embodiment, cleaning inside the water treatment system 15 is started with the microfiltration membrane device 27 installed in the preceding stage (immediately) of the ultrafiltration membrane device 28. Then, after a predetermined period of time has passed, the microfiltration membrane device 27 that captures metal particles, sand, etc., for example, is removed (separated) from the ultrapure water production device 10, and water treatment is performed. It is possible to remove the above-mentioned metal particles, sand, etc. from the inside. Therefore, according to the method for starting up the ultrapure water production apparatus 10 of the present embodiment, the elution of components such as sand and metal particles that may exist in the water treatment system 15 continues, and the quality of the ultrapure water deteriorates. You can avoid being stuck. That is, in the water treatment after removing the microfiltration membrane device 27, ultrapure water within the expected manufacturing specifications can be obtained quickly, thereby shortening the start-up period of the ultrapure water production device 10. can.

At any stage of this operation, it is possible to sterilize the inside of the secondary pure water production section 18 with hydrogen peroxide or the like. In this case, a line (not shown) that bypasses the polisher 26 and/or the ultrafiltration membrane device 28 is used to connect the polisher 26 and/or the ultrafiltration membrane device 28 to the system (water treatment system 15 ), and hydrogen peroxide is added into the system using a branch valve provided on the suction side of either the secondary pure water production unit 18 , for example, the tank 16 or the pump 22 . After that, circulation is performed for a predetermined time. After sufficient sterilization, the hydrogen peroxide solution is drained from some place. Bypassing the polisher 26 and/or the ultrafiltration membrane device 28 is stopped after the hydrogen peroxide in the system has disappeared.

Further, in the method for starting up the ultrapure water production apparatus of the present invention, the water treatment system 15 including the polisher 26 is cleaned while the ion exchange resin is not filled in the main body of the polisher 26. The cleaning operation may be stopped and the body of the polisher 26 may be filled with ion exchange resin.

Furthermore, the above operation has been described by applying the circulation line 31b including the point of use 20, but it is also possible to use the circulation line 31c bypassing the point of use 20 as shown in FIG. In that case, at some stage, an operation is performed to include the point of use 20 in the circulation line. In addition, in order to shorten the start-up time, it is preferable to select the start-up method in the circulation line 31b including the point of use 20. FIG.

In order to supplement the water supply by the circle pump 22, a booster pump 43 may be provided 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 producing section illustrated in FIGS. 2 and 3 or the secondary pure water producing section shown in FIG. 6, which will be described later.

On the other hand, with respect to the device configuration of the ultrapure water production device 10, an ultrapure water production device that does not have a temporary filter device (microfiltration membrane device 27) as described above was used, and cleaning was performed with cleaning water. In addition, it has been verified that when water treatment is performed, even if such washing and water treatment are continued for a period of, for example, four months, ultrapure water within manufacturing specifications cannot be obtained. In this case, the hollow fiber module in the ultrafiltration membrane device 28 is in a state where metal powder, sand, etc. are trapped, and the trapped foreign matter is pulverized over time and flows out to the subsequent stage. It didn't fit within the manufacturing specs. Therefore, by replacing all the hollow fiber modules in the ultrafiltration membrane device 28 with new ones and performing the water treatment again, ultrapure water within the manufacturing specifications was finally obtained.

In addition, when using an ultrapure water production apparatus having the same device configuration as the ultrapure water production apparatus 10 and with the microfiltration membrane device 27 attached, cleaning with cleaning water and water treatment are also performed. And even if the water treatment is continued for a period of, for example, three months, it has been verified that ultrapure water that falls within the manufacturing specifications cannot be obtained. In this case, the microfiltration membrane device 27 contains, for example, metal powder and sand of a size that can be seen with the naked eye. Ultrapure water was obtained that fits within the

On the other hand, according to the method for starting up the ultrapure water production apparatus 10 of the present embodiment, after one week of cleaning using the cleaning liquid containing hydrogen peroxide with the microfiltration membrane apparatus 27 installed, After removing the microfiltration membrane device 27 that captures, for example, metal particles and sand from the ultrapure water production device 10, water treatment is performed to immediately obtain ultrapure water that falls within the manufacturing specifications. It has been verified that

As described above, according to the startup method of the ultrapure water production apparatus 10 of the present embodiment (and the ultrapure water production apparatus 10 to which this startup method can be applied), a temporary filter device (microfiltration membrane By effectively utilizing the device 27) and the filter attachment/detachment mechanism 30 to perform cleaning and water treatment, it is possible to shorten the start-up period of the ultrapure water production device 10. FIG. As shown in FIG. 6, instead of the filter attaching/detaching mechanism 30 shown in FIG. 3, it is also possible to apply a filter attaching/detaching mechanism 40 to the ultrapure water production apparatus and its start-up method. In the case of this filter attachment/detachment mechanism 40, after the on-off valves 34 and 35 are closed, the piping 32 (branch flow path 32a) and the microfiltration membrane device 27 are removed ( separated). After removing the temporarily placed microfiltration membrane device 27 together with the on-off valves 34 and 35 and the pipe 32a from the ultrapure water production system 10, a blocking plug (stopper Plugs) 38, 39, etc. will be attached.

Although the present invention has been specifically described with reference to the embodiments, the present invention is not limited to the embodiments as they are, and various changes can be made in the implementation stage without departing from the scope of the invention. For example, some constituent elements may be deleted from all the constituent elements shown in the embodiments, and it is also possible to appropriately combine a plurality of constituent elements disclosed in the above embodiments.

10... Ultrapure water production device, 12... Pretreatment unit, 14... Primary pure water production unit, 15... Water treatment system, 16... Tank (TK), 18... Secondary pure water production unit, 20... Point of use (POU ), 22... Circle pump, 23... Heat exchanger (HEX), 24... Ultraviolet oxidation device (TOC-UV), 25... Membrane degassing device (MDG), 26... Polisher, 27... Microfiltration membrane device (MF) , 28... Ultrafiltration membrane device (UF), 29... Particle counter, 30, 40... Filter attachment/detachment mechanism, 31... Flow path, 31a... Pipe (first pipe), 31b, 31c... Circulation line, 32... Branch Flow path 32a Piping (second piping) 33 On-off valve (first on-off valve) 34, 35 On-off valve (second on-off valve) 36, 37, 41, 42 Joint, 38, 39... Closing plugs.

Claims (12)

Ultrapure water provided with a water treatment system including at least a flow path for flowing water to be treated, and an ultrafiltration membrane device provided on the flow path for treating the water to be treated before a point of use. A method for starting up a manufacturing apparatus,
A temporarily placed filter device is provided on the flow channel before the ultrafiltration membrane device, and a branch flow that once branches from the flow channel and merges on the downstream side of the flow channel while passing through the temporarily placed filter device. installing a path ;
a step of cleaning the water treatment system by starting to supply pure water along the channel after installing the temporary filter device;
a step of separating the temporarily placed filter device and the branch flow path from the ultrapure water production device after a predetermined period of time has elapsed since the start of cleaning by feeding the pure water;
A method for starting up an ultrapure water production apparatus having The washing includes a sterilization treatment,
The method for starting up the ultrapure water production apparatus according to claim 1. After the separating step, a step of starting to feed the water to be treated along the flow path and performing water treatment until ultrapure water within the desired manufacturing specifications is obtained;
The method for starting up an ultrapure water production apparatus according to claim 1 or 2, further comprising: The ultrapure water production apparatus further comprises a tank on the upstream side of the temporarily placed filter device on the branch flow path,
The flow path has a circulation line that returns to the tank after passing through the ultrafiltration membrane device ,
In the cleaning, the sent pure water is circulated through the circulation line;
A method for starting up an ultrapure water production apparatus according to any one of claims 1 to 3. The predetermined period is a period in which the number of circulations calculated from the water volume and flow rate in the circulation line is 0.5 to 2200 when the cleaning is started.
The method for starting up the ultrapure water production apparatus according to claim 4. The temporarily placed filter device has a filtration accuracy that separates particles of 0.2 μm or more,
A method for starting up an ultrapure water production apparatus according to any one of claims 1 to 5. The ultrafiltration membrane device has a plurality of hollow fiber modules,
A water flow rate per one of the hollow fiber modules is 10 m ³ /h or more.
A method for starting up an ultrapure water production apparatus according to any one of claims 1 to 6. Ultrapure water that fits within the expected manufacturing specifications has a particle size of 50 nm or more and the number of particles is 200/L or less.
A method for starting up an ultrapure water production apparatus according to any one of claims 1 to 7. a channel for flowing the water to be treated;
an ultrafiltration membrane device that is provided on the flow path and that treats the water to be treated before the point of use;
a filter attachment/detachment mechanism that is provided in front of the ultrafiltration membrane device on the flow path and enables attachment and detachment of a temporarily placed filter device to the flow path ,
The flow path is composed of a first pipe,
The filter attachment/detachment mechanism includes:
A second pipe, which once branches from the flow channel and forms a branched flow channel that merges on the downstream side of the flow channel via the temporarily placed filter device, can be removed from the first pipe. a plurality of fittings that connect to
a first on-off valve provided between the branch position and the confluence position in the first pipe;
An ultrapure water production device comprising: The temporarily placed filter device is a microfiltration membrane device,
The ultrapure water production apparatus according to claim 9. A pair of second on-off valves are provided on the second pipe before and after the temporarily placed filter device, respectively.
The ultrapure water production apparatus according to claim 9 .
A tank is further provided on the upstream side of the temporarily placed filter device on the flow path,
The ultrapure water production apparatus according to any one of claims 9 to 11, wherein the flow path has a circulation line returning to the tank after passing through the ultrafiltration membrane device.

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