WO2024014218A1

WO2024014218A1 - Ultrapure water production apparatus and method for operating ultrapure water production apparatus

Info

Publication number: WO2024014218A1
Application number: PCT/JP2023/021987
Authority: WO
Inventors: 浩一永田
Original assignee: 栗田工業株式会社
Priority date: 2022-07-14
Filing date: 2023-06-13
Publication date: 2024-01-18
Also published as: JP7513213B2; JPWO2024014218A1; TW202402687A

Abstract

A subsystem 4 of this ultrapure water production apparatus has: a first TOC meter 41 for measuring the TOC concentration on an inlet side of a first ultraviolet oxidation device 24; a hydrogen peroxide meter 42 for measuring the hydrogen peroxide concentration in water treated in a platinum group metal catalyst resin column 25; a dissolved oxygen (DO) meter 43 for measuring the dissolved oxygen concentration in water treated in a membrane-type deaeration device 26; and a second TOC meter 44 for measuring the TOC concentration in water treated in a non-regeneration type mixed bed ion exchange device 28. The first TOC meter 41 can send measurement data to a control means 45, and the control means 45 can control the first ultraviolet oxidation device 24 on the basis of the sent data. The first ultraviolet oxidation device 24 is composed of three blocks with two ultraviolet lamps per block, wherein the illumination level of the ultraviolet lamps can be adjusted within the range of 30%-100% for each block. Such an ultrapure water production apparatus can suppress excess ultraviolet irradiation in the ultraviolet oxidation device and can stably produce ultrapure water with a low TOC concentration.

Description

Ultrapure water production equipment and operating method of ultrapure water production equipment

The present invention relates to an ultrapure water production device equipped with a primary water purification device and a secondary water purification device, and a method of operating this ultrapure water production device, and particularly to an ultrapure water production device equipped with an ultraviolet oxidation device and a platinum group metal catalyst resin in the secondary water purification device. The present invention relates to an ultrapure water production apparatus having a column and a method of operating the ultrapure water production apparatus.

Conventionally, ultrapure water used in the electronics industry such as semiconductors is produced by ultrapure water production consisting of a pretreatment device, a primary water purification device, and a secondary deionization device (subsystem) that processes the primary water purification. It is manufactured by treating raw water with equipment.

In general, an ultrapure water production device 1 is comprised of three stages of devices: a pretreatment device 2, a primary deionization device 3, and a secondary deionization device (subsystem) 4, as shown in FIG. In the pretreatment device 2 of such an ultrapure water production device 1, the raw water W is subjected to pretreatments such as filtration, coagulation sedimentation, and microfiltration membrane, and mainly removes suspended solids.

The primary water deionization device 3 includes a tank 11 for pre-treated water W0, a reverse osmosis membrane device 12, a plurality of ultraviolet lamps, and an ultraviolet (UV) oxidation device 13 (hereinafter referred to as “UV” for convenience of explanation) whose output can be controlled. 2), a regenerative ion exchange device (mixed bed type or 4 bed 5 column type, etc.) 14, and a membrane deaerator 15. Note that 16 is a preheater. be. Here, most of the electrolyte, particulates, viable bacteria, etc. in the pretreated water W0 are removed, and organic matter is decomposed.

The subsystem 4 includes a subtank 21 that stores the primary pure water W1 produced by the above-mentioned primary water purifier 3, a pump 22 that supplies the primary pure water W1 stored in the subtank 21, and a pump 22 that supplies the primary pure water W1 stored in the subtank 21. An ultraviolet oxidation device 24 (hereinafter, for convenience of explanation, it may be referred to as the first ultraviolet oxidation device 24) whose output can be controlled by a plurality of ultraviolet lamps that process W1, a platinum group metal catalyst resin tower 25, and a membrane type It is composed of a deaerator 26, a reverse osmosis membrane device 27, a non-regenerative mixed bed ion exchange device 28, and an ultrafiltration (UF) membrane 29 as a membrane filtration device. It is an exchanger. In this subsystem 4, a trace amount of organic matter (TOC component) contained in the primary pure water W1 is oxidized and decomposed by ultraviolet rays in an ultraviolet oxidation device 24, and hydrogen peroxide generated by the irradiation with ultraviolet rays is transferred to a platinum group metal catalyst resin column. 25, and a subsequent membrane deaerator 26 removes dissolved gases such as DO (dissolved oxygen). Subsequently, residual carbonate ions, organic acids, anionic substances, as well as metal ions and cationic substances are removed by treatment with a reverse osmosis membrane device 27 and a non-regenerative mixed bed ion exchange device 28 . Then, ultrapure water (secondary pure water) W2 is obtained by removing particulates with an ultrafiltration (UF) membrane 29, and this is supplied to the use point 5 from the feed pipe 30, and the unused ultrapure water is The water is returned to the sub tank 21 from the return pipe 31.

In the ultrapure water production apparatus 1 as described above, the oxidative decomposition mechanism of the TOC component in the ultraviolet oxidation device 24 is to oxidize and decompose water to generate OH radicals, and use these OH radicals to oxidize and decompose the TOC component. Usually, the ultraviolet rays in this ultraviolet oxidation device 24 are irradiated in an excessive amount to sufficiently oxidize and decompose TOC in the water. When the amount of ultraviolet irradiation from the ultraviolet oxidation device 24 is large as described above, OH radicals generated by water decomposition become excessive, and the excess OH radicals combine to form hydrogen peroxide. The generated hydrogen peroxide is decomposed by contacting with the platinum group metal catalyst resin tower 25 in the latter stage, but in order to operate the platinum group metal catalyst resin tower 25 stably over a long period of time, it is necessary to reduce the hydrogen peroxide load. It is desirable that it be as low as possible.

Therefore, conventionally, the subsystem 4 had a configuration as shown in FIG. 5. That is, in the subsystem 4, a TOC meter 51 for measuring the TOC concentration on the inlet side of the first ultraviolet oxidizer 24 is provided after the first ultraviolet oxidizer 24, and a TOC meter 51 that measures the TOC concentration on the inlet side of the first ultraviolet oxidizer 24, and a TOC meter 51 that measures the TOC concentration on the inlet side of the first ultraviolet oxidizer 24 and A hydrogen peroxide meter 52 that measures the hydrogen oxide concentration, a dissolved oxygen meter 53 that measures the dissolved oxygen (DO) concentration of the water treated by the membrane deaerator 26, and a non-regenerative mixed bed ion exchange device 28. A TOC meter 54 is provided to measure the TOC concentration of the treated water. Here, the first ultraviolet oxidation device 24 is composed of a plurality of blocks, for example, two ultraviolet lamps per block, and about three blocks.

In such a subsystem 4, a TOC meter 51, a hydrogen peroxide meter 52, a dissolved oxygen meter 53, and a TOC meter 54 monitor the TOC concentration, hydrogen peroxide, and dissolved oxygen concentration, respectively. Then, according to the measurement result of the TOC concentration of the primary pure water W1 supplied to the first ultraviolet oxidizer 24 by the TOC meter 51, the number of lit ultraviolet lamps (the number of operating blocks) of the first ultraviolet oxidizer 24 is determined. By controlling the output through manual adjustment by a worker, excessive irradiation of ultraviolet rays in the first ultraviolet oxidizer 24 is suppressed as much as possible, and the amount of hydrogen peroxide produced is reduced.

However, in the ultrapure water production apparatus 1 equipped with the subsystem 4 as described above, the first ultraviolet oxidation device 24 is manually adjusted by turning on and off the number of lighting blocks of the ultraviolet lamp. It is not possible to quickly respond to changes in the quality of the primary pure water W1 supplied to the oxidizer 24. In addition, since control is performed by the number of lighting blocks of the ultraviolet lamp, delicate adjustment of the amount of ultraviolet irradiation is difficult. Therefore, there is a problem that excessive irradiation of ultraviolet rays may occur and generation of hydrogen peroxide cannot be sufficiently suppressed.

The present invention has been made in view of the above problems, and is capable of suppressing excessive irradiation of ultraviolet rays in an ultraviolet oxidation device in a subsystem and stably producing ultrapure water with a low TOC concentration. The purpose of the present invention is to provide an ultrapure water production device that can produce ultrapure water and a method of operating the ultrapure water production device.

In view of the above object, the present invention is, firstly, an ultrapure water production device comprising a primary water purification device and a secondary water purification device for further processing the primary pure water treated by the primary water purification device. , the secondary water deionization device includes a first ultraviolet oxidation device that irradiates the primary deionized water with ultraviolet rays to generate a first treated water, and a first ultraviolet oxidation device that processes the first treated water to generate a second treated water. a platinum group metal catalytic resin device that generates , a first TOC meter that measures the TOC concentration of the primary pure water provided on the inlet side of the first ultraviolet oxidation device, and a measured value of the first TOC meter. There is provided an ultrapure water production apparatus having a control means capable of controlling the output of the first ultraviolet oxidation apparatus based on (Invention 1).

According to this invention (invention 1), the output of the first ultraviolet oxidation device can be controlled by the control means based on the measured value of the first TOC meter, and the output of the first ultraviolet oxidation device can be controlled. Adjustments can be made quickly and frequently, reducing excessive UV irradiation in the first UV oxidizer and suppressing the production of hydrogen peroxide, preventing an increase in dissolved oxygen and producing ultraviolet oxidizers with low TOC concentrations. Pure water can be stably produced.

In the invention (invention 1), the primary water purification device includes a second ultraviolet oxidation device and a third TOC meter that measures the TOC concentration of the water to be treated in the second ultraviolet oxidation device, The secondary water deionization device includes a membrane deaerator that processes the second treated water to generate deaerated water after the platinum group metal catalyst resin device, and a membrane deaerator that generates deaerated water by treating the second treated water, and a membrane deaerator that generates deaerated water after the platinum group metal catalyst resin device. a dissolved oxygen meter provided, a non-regenerative mixed ion exchange device that processes this degassed water to produce third treated water, and a third non-regenerative mixed ion exchange device provided after the non-regenerative mixed ion exchange device. a second TOC meter that measures the TOC concentration of the treated water, the control means being able to control the output of the second ultraviolet oxidation device based on the measured value of the third TOC meter, Furthermore, it is preferable that the output of the second ultraviolet oxidation device can be corrected based on the measured values of the dissolved oxygen meter and the second TOC meter (invention 2).

According to this invention (invention 2), the output of the first ultraviolet oxidation device is adjusted by the control means based on the measured value of the first TOC meter, and the output of the first ultraviolet oxidation device is adjusted based on the measured value of the third TOC meter. The output of the second UV oxidizer can be adjusted. Furthermore, based on the measured values of the dissolved oxygen meter and the second TOC meter, the output of the second ultraviolet oxidation device is corrected so that the TOC concentration of the primary pure water treated with the first ultraviolet oxidation device is optimized. Therefore, by minimizing the excessive irradiation of ultraviolet rays in the first ultraviolet oxidation device, it is possible to suppress the generation of hydrogen peroxide and stably produce ultrapure water with a particularly low TOC concentration. can.

The present invention also provides an ultrapure water production device comprising a primary pure water device and a secondary pure water device for further processing the primary purified water treated by the primary pure water device, wherein the secondary pure water The device includes a first ultraviolet oxidation device that irradiates the primary pure water with ultraviolet rays to generate a first treated water, and a platinum group metal that processes the first treated water to generate a second treated water. a catalytic resin device, a membrane deaerator that processes the second treated water to generate deaerated water, which is provided downstream of the platinum group metal catalytic resin device, and a membrane deaerator that is provided downstream of the membrane deaerator. a dissolved oxygen meter provided, a non-regenerative mixed ion exchange device that processes the degassed water to produce third treated water, and a third non-regenerative mixed ion exchange device provided after the non-regenerative mixed ion exchange device. a second TOC meter for measuring the TOC concentration of the treated water; and a control means capable of controlling the output of the first ultraviolet oxidation device based on the measured value of the second TOC meter. A pure water production device is provided (Invention 3).

According to this invention (invention 3), the control means adjusts the output of the first ultraviolet oxidation device by feedback control based on the measured value of TOC of the third treated water, which is the final treated water. By reducing excessive irradiation of ultraviolet rays in the first ultraviolet oxidation device and suppressing the production of hydrogen peroxide, it is possible to prevent an increase in dissolved oxygen and stably produce ultrapure water with a low TOC concentration. .

In the above invention (invention 3), the primary water deionization device includes a second ultraviolet oxidation device and a fourth TOC meter that measures the TOC concentration of the treated water of the second ultraviolet oxidation device, and the The secondary water deionization device has a dissolved oxygen meter downstream of the membrane deaerator, and the control means controls the output of the second ultraviolet oxidation device based on the measured value of the fourth TOC meter. It is preferable that the output of the second ultraviolet oxidation device can be controlled based on the measured values of the dissolved oxygen meter and the second TOC meter (invention 4).

According to this invention (invention 4), the control means can adjust the output of the second ultraviolet oxidation device by feedback control based on the measured value of the fourth TOC meter. Furthermore, based on the measured value of TOC of the dissolved oxygen meter and the third treated water, which is the final treated water, the TOC concentration of the primary pure water to be treated with the first ultraviolet oxidation device is optimized. Since the output of the second ultraviolet oxidation device can be corrected, by minimizing the excessive irradiation of ultraviolet rays in the first ultraviolet oxidation device, the production of hydrogen peroxide can be suppressed, and ultrapure hydrogen peroxide with a particularly low TOC concentration can be produced. Water can be produced stably.

In the above invention (invention 2 or 4), the first ultraviolet oxidation device and the second ultraviolet oxidation device are composed of a plurality of blocks of ultraviolet lamps, and the illuminance of each ultraviolet lamp is controllable. Preferable (invention 5).

According to the invention (invention 5), the output of the ultraviolet oxidizer can be finely adjusted by controlling the number of blocks in which the ultraviolet oxidizer operates and the illumination intensity of the ultraviolet lamp using the control means.

Second, the present invention provides ultrapure water that processes treated raw water with a primary water purifier to produce primary pure water, and further processes this primary pure water with a secondary water purifier to produce secondary pure water. The production method includes a first ultraviolet oxidation step in which the primary pure water is irradiated with ultraviolet rays to produce a first treated water, and a second treatment in which hydrogen peroxide in the first treated water is decomposed. A platinum group metal catalyst resin treatment step for generating water; and a step of measuring the TOC concentration of the primary pure water before the ultraviolet oxidation step and controlling the amount of ultraviolet rays irradiated to the primary pure water based on this TOC concentration. (Invention 6).

According to this invention (Invention 6), the TOC concentration of the primary pure water before the ultraviolet oxidation step is measured, and the amount of ultraviolet rays irradiated to the primary pure water is controlled based on this TOC concentration. The output of the ultraviolet oxidizer can be adjusted quickly and frequently, reducing excessive ultraviolet irradiation in the ultraviolet oxidizer and suppressing the production of hydrogen peroxide, thereby preventing an increase in dissolved oxygen and increasing TOC. Ultrapure water with low concentration can be stably produced.

In the above invention (invention 6), in the primary water purification device, a second ultraviolet oxidation step in which the water to be treated is irradiated with ultraviolet rays and a TOC concentration of the water to be treated in this second ultraviolet oxidation step are measured. , a step of controlling the amount of ultraviolet irradiation in the second ultraviolet oxidation step, and in the secondary water purification device, after the platinum group metal catalyst resin treatment step, the dissolved gas in the second treated water is In producing the third treated water, a degassing step removes ionic impurities to produce deaerated water, and a deionization step removes ionic impurities from this deaerated water to produce the third treated water. , while measuring the dissolved oxygen concentration of the deaerated water, the TOC concentration of the third treated water, and based on the dissolved oxygen concentration and the TOC concentration of the third treated water, the second It is preferable to adjust the amount of ultraviolet ray irradiation in the ultraviolet oxidation step (Invention 7).

According to this invention (Invention 7), in the primary water purification device, the amount of ultraviolet rays to be treated in the second ultraviolet oxidation device is controlled based on the TOC concentration of the water to be treated in the second ultraviolet oxidation step. . Furthermore, when generating the third treated water in the secondary water purification device, the dissolved oxygen concentration of the degassed water is measured, and the TOC concentration of the third treated water is measured, and this dissolved oxygen concentration and the third treated water are measured. By correcting the amount of ultraviolet irradiation in the second ultraviolet oxidation step so that the TOC concentration of the primary pure water treated in the first ultraviolet oxidation step is optimized based on the TOC concentration in the treated water. By minimizing excessive irradiation of ultraviolet rays in the ultraviolet oxidation device, generation of hydrogen peroxide can be suppressed, and ultrapure water with a low TOC concentration can be stably produced.

Furthermore, the present invention provides ultrapure water production in which the treated raw water is treated with a primary water purification device to produce primary pure water, and the primary pure water is further processed with a secondary water purification device to produce secondary pure water. The method includes, in the secondary water purification device, a first ultraviolet oxidation step of irradiating the primary pure water with ultraviolet rays to produce a first treated water, and hydrogen peroxide in the first treated water. a platinum group metal catalyst resin treatment step of decomposing to generate second treated water; and after the platinum group metal catalyst resin treatment step, removing gas dissolved in the second treated water to generate degassed water. a degassing step and a deionization step of removing ionic impurities from the degassed water to produce third treated water, a step of measuring the TOC concentration of the third treated water, and a step of measuring the TOC concentration of the third treated water; There is provided a method for operating an ultrapure water production apparatus, comprising the step of controlling the output of the first ultraviolet oxidation apparatus based on the TOC concentration of the treated water (invention 8).

According to this invention (Invention 8), by adjusting the output of ultraviolet rays in the first ultraviolet oxidation step by feedback control based on the measured value of TOC of the third treated water which is the final treated water, By reducing excessive irradiation with ultraviolet rays in the first ultraviolet oxidation step and suppressing the production of hydrogen peroxide, it is possible to prevent an increase in dissolved oxygen and stably produce ultrapure water with a low TOC concentration.

In the above invention (invention 8), in the primary water purification device, a second ultraviolet oxidation step of irradiating the treated object with ultraviolet rays and a TOC concentration of the treated water of this second ultraviolet oxidation step are measured; and a step of controlling the amount of ultraviolet irradiation in the second ultraviolet oxidation step, and in the secondary water purification device, the dissolved oxygen concentration of the degassed water is measured, and the TOC concentration of the third treated water is measured. It is preferable to measure the amount of ultraviolet rays in the second ultraviolet oxidation step based on the dissolved oxygen concentration and the TOC concentration of the third treated water (invention 9).

According to this invention (invention 9), the output of ultraviolet light in the second ultraviolet oxidation step can be adjusted by feedback control based on the measured value of the fourth TOC meter by the control means. Furthermore, based on the dissolved oxygen concentration and the measured TOC value of the third treated water, which is the final treated water, the TOC concentration of the primary pure water to be treated in the first ultraviolet oxidation step is optimized. Since the output of the second ultraviolet oxidation step can be corrected, by minimizing the excessive irradiation of ultraviolet rays in the first ultraviolet oxidation step, the production of hydrogen peroxide can be suppressed, making it possible to suppress the production of hydrogen peroxide, especially for ultrapure products with low TOC concentrations. Water can be produced stably.

In the above invention (invention 7 or 9), the first ultraviolet oxidation step and the second ultraviolet oxidation step are performed using an ultraviolet oxidation device, and the ultraviolet oxidation device is composed of a plurality of blocks of ultraviolet lamps. In addition, it is preferable that the illumination intensity of each ultraviolet lamp is controllable, and that the amount of ultraviolet irradiation is controlled by the number of operating blocks of the ultraviolet lamp and the illuminance of each ultraviolet lamp (invention 10).

According to the invention (invention 10), the output of the ultraviolet oxidizer can be finely adjusted by controlling the number of blocks in which the ultraviolet oxidizer operates and the illumination intensity of the ultraviolet lamp.

The ultrapure water production apparatus of the present invention includes a primary pure water apparatus and a secondary pure water apparatus that further processes the primary purified water treated by the primary pure water apparatus. It is equipped with an ultraviolet oxidation device of Since it adjusts the output of the device, it reduces excessive irradiation of ultraviolet rays in the first ultraviolet oxidation device, suppresses the production of hydrogen peroxide, prevents an increase in dissolved oxygen, and produces ultrapure products with a low TOC concentration. Water can be produced stably.

1 is a schematic diagram showing an ultrapure water production apparatus to which the present invention can be applied. 1 is a schematic diagram showing a subsystem in an ultrapure water production apparatus according to a first embodiment of the present invention. It is a schematic diagram showing an ultrapure water production apparatus according to a second embodiment of the present invention. It is a schematic diagram showing an ultrapure water production apparatus according to a third embodiment of the present invention. 1 is a schematic diagram showing a conventional subsystem in an ultrapure water production device.

[First embodiment]
Hereinafter, a first embodiment of the ultrapure water production apparatus of the present invention will be described with reference to FIGS. 1 and 2.

(Ultrapure water production equipment)
The ultrapure water production apparatus of this embodiment has the same basic overall configuration as that shown in FIG. 1 described above, and is characterized by the subsystem 4.

<Subsystem 4>
In this embodiment, the subsystem 4 includes a first TOC meter 41 that measures the TOC concentration on the inlet side of the first ultraviolet oxidizer 24, and treated water from the platinum group metal catalyst resin column 25, as shown in FIG. A hydrogen peroxide meter 42 that measures the hydrogen peroxide concentration of the (second treated water), a dissolved oxygen meter 43 that measures the dissolved oxygen (DO) concentration of the treated water of the membrane deaerator 26, and a non-regenerated It has a second TOC meter 44 that measures the TOC concentration of the treated water (third treated water) of the mixed bed type ion exchange device 28. The first TOC meter 41 can transmit measurement data to a control means 45 such as a personal computer, and the control means 45 can control the first ultraviolet oxidation device 24 based on this transmitted data. It becomes.

Here, the first ultraviolet oxidation device 24 is composed of a plurality of blocks of ultraviolet lamps each including a plurality of ultraviolet lamps, and the control means 45 described above controls the number of blocks to be lit and also controls the ultraviolet rays of each block. It is preferable that the output of ultraviolet rays in the first ultraviolet oxidizer 24 can be controlled by adjusting the illuminance of the lamp. As the above-mentioned ultraviolet oxidation device 24, it is possible to use “JPW”, “JPH”, and “ZK-UV” manufactured by Nippon Photoscience Co., Ltd., which can adjust both the illuminance of the ultraviolet lamp and the number of lighting blocks. can. In addition, "COX", "WOX", and "NWOX" manufactured by Chiyoda Kohan Co., Ltd. are examples of UV lamps that only have the function of adjusting the illumination intensity. It is preferable to use one that can adjust both the number of lighting blocks and the number of lit blocks, and in particular, “JPW” and “ZK-UV” manufactured by Nippon Photo Science Co., Ltd. are preferable because they have high TOC decomposition performance. Specifically, in this embodiment, each block consists of three blocks with two ultraviolet lamps, and the illuminance of the ultraviolet lamps can be adjusted in the range of 30 to 100% for each block. . With such a configuration, the number of lighting blocks is 1 to 3, so the amount of ultraviolet rays from the ultraviolet lamp can be adjusted in the range of 10 to 100% of the maximum output of ultraviolet rays.

(How to operate ultrapure water production equipment)
A method of operating the ultrapure water production apparatus 1 as described above will be described below.
First, when the raw water W is supplied to the pretreatment device 2, suspended matter and colloidal substances in the raw water W are removed by coagulation, pressurized flotation (sedimentation), filtration (membrane filtration), etc., and the raw water is treated as raw water. Pretreated water W0 is obtained. In this process, polymeric organic substances, hydrophobic organic substances, etc. are also removed to some extent.

This pretreated water W0 is supplied to the primary water purifier 3 and temporarily stored in the tank 11, and then sent by a pump (not shown) and preheated by a preheater 16 to reduce the viscosity of the pretreated water W0, which is then used to reduce the viscosity of the pretreated water W0, which is then used to reduce the viscosity of the pretreated water W0. Supply to 12. By treating the water to be treated with this reverse osmosis membrane device 12 at a predetermined recovery rate, salts are removed, as well as ionic and colloidal TOC. Next, the second ultraviolet oxidation device 13 reduces the TOC component to a predetermined level (second ultraviolet oxidation step). Subsequently, ionic components such as salts are removed by a regenerative ion exchange device 14. Then, in the membrane deaerator 15, inorganic carbon (IC) and dissolved oxygen are removed to produce primary pure water W1.

This primary pure water W1 is sent to the subsystem 4 via piping 17. In the subsystem 4, primary pure water W1 is pumped by a pump 22, and a first ultraviolet oxidation device 24 using a low-pressure ultraviolet oxidation device converts TOC into an organic acid and further with ultraviolet light of about 185 nm emitted from a low-pressure ultraviolet lamp. It is decomposed to _CO2 level to produce the first treated water (first ultraviolet oxidation step). Next, hydrogen peroxide (H ₂ O ₂ ) is decomposed into water (H ₂ O ₂ ) and oxygen (O ₂ ) in the platinum group metal catalyst resin tower 25 to generate second treated water (platinum group metal catalyst resin column 25). metal catalyst resin treatment process). Next, the oxygen generated here and dissolved carbon dioxide are removed by a membrane deaerator 26, and then trace amounts of remaining low molecular weight organic matter and ionic impurities are removed by a reverse osmosis membrane 27 and a non-regenerative mixed bed ion exchanger. It is removed in the device 28 to produce third treated water (deionization step). Then, in the ultrafiltration (UF) membrane 29, fine particles are removed, and ultrapure water W2 can be produced by removing fine particles flowing out from the non-regenerative mixed bed ion exchange device 28 and the like.

In the manufacturing process of the ultrapure water production device 1 as described above, the TOC concentration of the primary pure water W1 flowing into the first ultraviolet oxidation device 24 is measured by the first TOC meter 41, and control is performed based on this measurement value. The means 45 controls the output of the first ultraviolet oxidizer 24 so that the amount of ultraviolet rays is necessary for decomposing TOC. At this time, in this embodiment, the first ultraviolet oxidation device 24 is composed of a plurality of blocks of about three blocks with two ultraviolet lamps per block. Since the light can be adjusted within the range of ~100%, the amount of ultraviolet rays from the UV lamp is adjusted within the range of approximately 10~100% of the maximum output of the ultraviolet rays of the first ultraviolet oxidizer 24. be able to. As a result, according to the TOC concentration of the primary pure water W1, which is the water to be treated by the first ultraviolet oxidation device 24, the output of ultraviolet rays can be quickly adjusted to an appropriate value, compared to the case where the treatment is performed only by turning on the number of ultraviolet lamps. Therefore, by reducing excessive irradiation of ultraviolet rays in the first ultraviolet oxidation device 24 and suppressing the generation of hydrogen peroxide, an increase in dissolved oxygen is prevented and the ultrapure water W2 with a low TOC concentration is stabilized. It can be manufactured by Adjustment of the ultraviolet output in the first ultraviolet oxidizer 24 is performed by determining the optimum amount of ultraviolet irradiation based on the correlation between the amount of primary pure water W1 processed in the subsystem 4 and the TOC concentration measured by the first TOC meter 41. Calculate in advance and perform the calculation based on this.

Furthermore, the dissolved oxygen concentration and TOC concentration of the ultrapure water W2 may be measured using the dissolved oxygen meter 43 and the second TOC meter 44, and it may be monitored whether the required water quality of the ultrapure water W2 is satisfied.

[Second embodiment]
Next, a second embodiment of the ultrapure water production apparatus of the present invention will be described with reference to FIGS. 1 and 3.

(Ultrapure water production equipment)
The basic overall configuration of the ultrapure water production apparatus of this embodiment is the same as that shown in FIG. 1 described above.

As shown in FIG. 3, in this embodiment, a third TOC meter 46 that measures the TOC concentration on the inlet side of the second ultraviolet oxidation device 13 of the primary water purification device 3 and the treated water of the regenerative ion exchange device 14 are used. The third TOC meter 46 is capable of transmitting measurement data to the control means 45, and is connected to the dissolved oxygen meter 43 of the subsystem 4 and the fourth TOC meter 47. It has the same configuration as the first embodiment described above, except that the measurement data of the second TOC meter 44 can also be transmitted to the control means 45. The control means 45 is capable of controlling the output of the second ultraviolet oxidizer 13 based on the measurement data of the third TOC meter 46, and also controls the dissolved oxygen meter 43 and the second TOC meter 44. The output of the second ultraviolet oxidizer 13 can be corrected based on the measured data.

The second ultraviolet oxidation device 13 has the same configuration as the first ultraviolet oxidation device 24 described above, and is composed of a plurality of blocks of ultraviolet lamps each including a plurality of ultraviolet lamps. It is preferable that the output of ultraviolet rays can be controlled by controlling the number of lit blocks and adjusting the illuminance of each ultraviolet lamp. Specifically, in this embodiment, each block consists of three blocks with two ultraviolet lamps, and the illuminance of the ultraviolet lamps can be adjusted in the range of 30 to 100% for each block. . With this configuration, the number of lighting blocks is 1 to 3, so the amount of ultraviolet rays from the ultraviolet lamp can be adjusted within a range of about 10 to 100% of the maximum output of ultraviolet rays. .

(How to operate ultrapure water production equipment)
A method of operating the ultrapure water production apparatus 1 of the second embodiment as described above will be described below. The ultrapure water production process in the ultrapure water production apparatus 1 of this embodiment is the same as that of the first embodiment described above, so detailed explanation thereof will be omitted.

In the manufacturing process of the ultrapure water production device 1 of this embodiment, in the primary water purification device 3, the third TOC meter 46 measures the TOC concentration of the water to be treated flowing into the second ultraviolet oxidation device 13. Based on the measured value, the control means 45 controls the output of the second ultraviolet oxidizer 13 so that the amount of ultraviolet rays necessary for decomposing TOC is obtained ((1) in FIG. 3). At this time, in this embodiment, the second ultraviolet oxidation device 13 is composed of a plurality of blocks of about three blocks, with two ultraviolet lamps per block, and the illumination intensity of the ultraviolet lamp is adjusted to 30 Since the light can be adjusted within the range of ~100%, the amount of ultraviolet irradiation from the UV lamp is adjusted within the range of approximately 10~100% of the maximum output of the ultraviolet rays of the second ultraviolet oxidizer 13. be able to.

Further, in the subsystem 4, the TOC concentration of the primary pure water W1 flowing into the first ultraviolet oxidation device 24 is measured by the first TOC meter 41, and based on this measurement value, the control means 45 controls the decomposition of TOC. The output of the first ultraviolet oxidizer 24 is controlled so that the required amount of ultraviolet rays is obtained ((2) in FIG. 3). At this time, in this embodiment, the first ultraviolet oxidation device 24 is composed of a plurality of blocks of about three blocks with two ultraviolet lamps per block. Since the light can be adjusted within the range of ~100%, the amount of ultraviolet rays from the UV lamp is adjusted within the range of approximately 10~100% of the maximum output of the ultraviolet rays of the first ultraviolet oxidizer 24. be able to.

On the other hand, in the primary water purifier 3, when the TOC in the primary pure water W1 becomes sufficiently low, the amount of TOC decomposed in the first ultraviolet oxidizer 24 of the subsystem 4 is small, so that the first ultraviolet rays as described above If only the output of the ultraviolet rays in the oxidizer 24 is controlled, the amount of ultraviolet rays irradiated to the TOC may be extremely excessive. In this case, the amount of hydrogen peroxide (H ₂ O ₂ ) generated in the first ultraviolet oxidation device 24 increases. When this becomes noticeable, the dissolved oxygen concentration in the second treated water treated in the platinum group metal catalyst resin tower 25 increases and hydrogen peroxide (H ₂ O ₂ ) also breaks out, causing the dissolved oxygen in the treated water in the membrane deaerator 26 to increase. Either the oxygen concentration will increase or the organic matter (TOC) in the third treated water will increase due to the ion exchange resin in the non-regenerative mixed bed ion exchange device 28. Therefore, in this embodiment, the dissolved oxygen concentration is measured by a dissolved oxygen meter 43 downstream of the membrane deaerator 26, and a second TOC meter 44 is measured downstream of the non-regenerative mixed bed ion exchange device 28. If the TOC concentration of the third treated water is measured and one or both of them shows a tendency to increase, the control means 45 determines that the TOC concentration of the primary pure water W1 is too low, The TOC concentration of the primary pure water W1, which is the water to be treated in the first ultraviolet oxidation device 24, is increased. Specifically, the control means 45 controls the second ultraviolet oxidizer 13 to reduce its ultraviolet output ((3) in FIG. 3). The degree of reduction in the output of ultraviolet rays is calculated using a pre-calculated formula based on the amount of primary pure water W1 processed in the subsystem 4 and the rising tendency of the dissolved oxygen meter 43 and the second TOC meter 44. Bye. This can improve the increase in dissolved oxygen concentration in the first treated water.

According to the ultrapure water production apparatus of the second embodiment as described above, the TOC concentration of the primary pure water W1, which is the water to be treated by the first ultraviolet oxidation apparatus 24, is In addition to optimally controlling the output of ultraviolet rays in the first ultraviolet oxidizer 24, it also controls the second ultraviolet oxidizer 13 of the primary water purification device 3 so that the decomposition of TOC in the first ultraviolet oxidizer 24 is optimized. Therefore, by further reducing excessive irradiation of ultraviolet rays in the first ultraviolet oxidation device 24 and suppressing the generation of hydrogen peroxide, an increase in dissolved oxygen is prevented and the ultrapure water W2 with a low TOC concentration is stabilized. It can be manufactured using

[Third embodiment]
Furthermore, a third embodiment of the ultrapure water production apparatus of the present invention will be described with reference to FIGS. 1 and 4.

As shown in FIG. 4, in this embodiment, a third TOC meter 46 that measures the TOC concentration on the inlet side of the second ultraviolet oxidation device 13 of the primary water purification device 3 and the treated water of the regenerative ion exchange device 14 are used. The fourth TOC meter 47 is capable of transmitting measurement data to the control means 45, and the control means 45 is configured to measure the TOC concentration of the fourth TOC meter 47. The second ultraviolet oxidation device 13 can be controlled based on the data of 47.

The subsystem 4 also includes a first TOC meter 41 that measures the TOC concentration on the inlet side of the first ultraviolet oxidizer 24, and a filter for treating water (second treated water) in the platinum group metal catalyst resin column 25. A hydrogen peroxide meter 42 that measures hydrogen oxide concentration, a dissolved oxygen meter 43 that measures dissolved oxygen (DO) concentration, and treated water (third treated water) of non-regenerative mixed bed ion exchange device 28. It has a dissolved oxygen meter 43 that measures dissolved oxygen (DO) concentration and a second TOC meter 44 that measures TOC concentration. The dissolved oxygen meter 43 and the second TOC meter 44 are capable of transmitting measurement data to the control means 45, and the control means 45 transmits the measurement data to the first TOC meter 44 based on the measurement data of the second TOC meter 44. The ultraviolet output of the ultraviolet oxidizer 24 can be controlled, and the ultraviolet output of the second ultraviolet oxidizer 13 can be corrected based on the measurement data of the dissolved oxygen meter 43 and the second TOC meter 44. It has become.

(How to operate ultrapure water production equipment)
A method of operating the ultrapure water production apparatus 1 of the third embodiment as described above will be described below.
The ultrapure water production process in the ultrapure water production apparatus 1 of this embodiment is the same as that of the first embodiment described above, so detailed explanation thereof will be omitted.

In the operation process of the ultrapure water production apparatus 1 of this embodiment, the primary water purification apparatus 3 assumes in advance the TOC concentration of the treated water of the regenerative ion exchange apparatus 14 measured by the fourth TOC meter 47. The amount of TOC decomposed by the second ultraviolet oxidation device 13 is determined based on the difference in the TOC concentration of the treated water from the regenerative ion exchange device 14, and feedback control is performed to determine whether the amount of TOC decomposed by the second ultraviolet oxidation device 13 is too much or not. The output of the second ultraviolet oxidizer 13 is controlled so that the amount of UV oxidation is maintained ((1) in FIG. 4). At this time, in this embodiment, the second ultraviolet oxidation device 13 is composed of a plurality of blocks of about three blocks, with two ultraviolet lamps per block, and the illumination intensity of the ultraviolet lamp is adjusted to 30 Since the light can be adjusted within the range of ~100%, the amount of ultraviolet irradiation from the UV lamp is adjusted within the range of approximately 10~100% of the maximum output of the ultraviolet rays of the second ultraviolet oxidizer 13. be able to.

In addition, in the subsystem 4, the measurement data of the second TOC meter 44 of the treated water (third treated water) of the non-regenerative mixed bed ion exchanger 28, which is the final water quality, and the data assumed in advance are used. The output of the first ultraviolet oxidation device 24 is controlled by feedback control based on the difference in the TOC concentration of the treated water from the non-regenerative mixed bed ion exchange device 28 ((2) in FIG. 4). At this time, in this embodiment, the first ultraviolet oxidation device 24 is composed of a plurality of blocks of about three blocks with two ultraviolet lamps per block. Since the light can be adjusted within the range of ~100%, the amount of ultraviolet rays from the UV lamp is adjusted within the range of approximately 10~100% of the maximum output of the ultraviolet rays of the first ultraviolet oxidizer 24. be able to.

On the other hand, in the primary water deionization device 3, when the TOC in the primary deionization water W1 becomes sufficiently low, less TOC is decomposed in the first ultraviolet oxidation device 24 of the subsystem 4. If only the output of the ultraviolet rays in the device 24 is controlled, the amount of ultraviolet rays irradiated to the TOC may be extremely excessive. In this case, the amount of hydrogen peroxide (H ₂ O ₂ ) generated in the first ultraviolet oxidation device 24 increases. If this becomes noticeable, hydrogen peroxide (H ₂ O ₂ ) will break through the platinum group metal catalyst resin column 25, and the dissolved oxygen concentration of the treated water in the membrane deaerator 26 will increase, or the non-regenerative mixed bed ion exchange Organic matter (TOC) will be generated due to the ion exchange resin in device 28. Therefore, in this embodiment, the dissolved oxygen concentration is measured by the dissolved oxygen meter 43 at the latter stage of the non-regenerative mixed bed type ion exchange device 28, and the TOC concentration is also measured by the second TOC meter 44, and either one of these is used. , or both show a tendency to increase, the TOC concentration of the primary pure water W1, which is the water to be treated in the first ultraviolet oxidation device 24, is increased ((3) in FIG. 4). Specifically, the control means 45 controls the second ultraviolet oxidizer 13 to reduce its ultraviolet output. The degree of reduction in the ultraviolet output can be calculated using a pre-calculated formula based on the amount of primary pure water W1 processed in the subsystem 4 and the rising tendency of the dissolved oxygen meter 43 and the second TOC meter 44. good.

According to the third embodiment as described above, depending on the dissolved oxygen concentration and TOC concentration in the final treated water, the treated water of the non-regenerative mixed bed ion exchange device 28 (third treated water). In addition to adjusting the first ultraviolet oxidation device 24 to an appropriate ultraviolet output through feedback control, the Since it controls the second ultraviolet oxidation device 13, excessive irradiation of ultraviolet rays in the first ultraviolet oxidation device 24 is further reduced, and by suppressing the generation of hydrogen peroxide, an increase in dissolved oxygen is prevented and the TOC is Ultrapure water W2 with low concentration can be stably produced.

Above, reference has been made to the attached drawings regarding the ultrapure water production apparatus and its operating method according to the present embodiment, but the present invention can be applied as long as the subsystem 4 includes an ultraviolet oxidation device and a platinum group metal catalyst resin column. Therefore, it can be particularly suitably applied to ultrapure water production equipment that has an ultraviolet oxidation device in the primary water purification equipment, but there are no particular restrictions on other configurations, and reverse osmosis membrane equipment or electrodeionization equipment can be used. General-purpose devices such as devices may be appropriately arranged. Further, feedforward control as in the second embodiment and feedback control as in the third embodiment may be used together.

1 Ultrapure water production equipment 2 Pre-treatment equipment 3 Primary water purification equipment 4 Secondary water purification equipment (subsystem)
5 Use point 11 Tank 12 Reverse osmosis membrane device 13 Ultraviolet (UV) oxidation device (second ultraviolet oxidation device)
14 Regenerative ion exchange device 15 Membrane deaerator 16 Preheater 17 Piping 21 Sub-tank 22 Pump 23 Heat exchanger 24 Ultraviolet oxidation device (first ultraviolet oxidation device)
25 Platinum group metal catalyst resin column 26 Membrane deaerator 27 Reverse osmosis membrane device 28 Non-regenerative mixed bed ion exchange device 29 Ultrafiltration (UF) membrane (membrane filtration device)
30 Feed pipe 31 Return pipe 41 First TOC meter 42 Hydrogen peroxide meter 43 Dissolved oxygen meter 44 Second TOC meter 45 Control means 46 Third TOC meter 47 Fourth TOC meter W Raw water W0 Pretreated water W1 Primary pure water W2 Ultra pure water (secondary pure water)

Claims

An ultrapure water production device comprising a primary water purification device and a secondary water purification device that further processes the primary pure water treated with the primary water purification device,
The secondary water deionization device includes a first ultraviolet oxidation device that generates first treated water by irradiating the primary deionization water with ultraviolet rays;
a platinum group metal catalyst resin device that processes the first treated water to generate second treated water;
a first TOC meter that measures the TOC concentration of primary pure water provided on the inlet side of the first ultraviolet oxidation device;
An ultrapure water production device comprising: control means capable of controlling the output of the first ultraviolet oxidation device based on the measured value of the first TOC meter.
The primary water deionization device includes a second ultraviolet oxidation device and a third TOC meter that measures the TOC concentration of the water to be treated in the second ultraviolet oxidation device; a membrane-type deaerator that processes the second treated water to generate deaerated water after the platinum group metal catalyst resin device; a dissolved oxygen meter provided after the membrane-type deaerator; A non-regenerative mixed ion exchange device that processes degassed water to produce third treated water, and a TOC concentration of the third treated water provided at a downstream stage of the non-regenerative mixed ion exchange device. a second TOC meter, and the control means is capable of controlling the output of the second ultraviolet oxidation device based on the measured value of the third TOC meter, and further includes a second TOC meter and a second TOC meter. The ultrapure water production device according to claim 1, wherein the output of the second ultraviolet oxidation device can be corrected based on the measured value of the TOC meter.
An ultrapure water production device comprising a primary water purification device and a secondary water purification device that further processes the primary pure water treated with the primary water purification device,
The secondary water purification device includes a first ultraviolet oxidation device that irradiates the primary pure water with ultraviolet rays to generate first treated water, and a first ultraviolet oxidation device that processes the first treated water to generate second treated water. a platinum group metal catalyst resin device for generating degassed water; a membrane deaerator for treating the second treated water to generate degassed water provided after the platinum group metal catalyst resin device; a dissolved oxygen meter installed downstream of the gas device; a non-regenerative mixed ion exchange device that processes the degassed water to produce third treated water; and a dissolved oxygen meter installed downstream of the non-regenerative mixed ion exchange device. a second TOC meter that measures the TOC concentration of the third treated water,
An ultrapure water production device comprising a control means capable of controlling the output of the first ultraviolet oxidation device based on the measured value of the second TOC meter.
The primary water deionization device includes a second ultraviolet oxidation device and a fourth TOC meter that measures the TOC concentration of the water treated by the second ultraviolet oxidation device; A dissolved oxygen meter is provided downstream of the type deaerator, and the control means is capable of controlling the output of the second ultraviolet oxidation device based on the measured value of the fourth TOC meter, and The ultrapure water production device according to claim 3, wherein the output of the second ultraviolet oxidation device can be corrected based on the measured values of the TOC meter and the second TOC meter.
The ultrapure water production according to claim 2 or 4, wherein the first ultraviolet oxidation device and the second ultraviolet oxidation device are composed of a plurality of blocks of ultraviolet lamps, and the illuminance of each ultraviolet lamp is controllable. Device.
An ultrapure water production method in which treated raw water is processed with a primary water purification device to produce primary pure water, and this primary pure water is further processed with a secondary water purification device to produce secondary pure water, the method comprising:
a first ultraviolet oxidation step of generating first treated water by irradiating the primary pure water with ultraviolet rays;
a platinum group metal catalyst resin treatment step of decomposing hydrogen peroxide in the first treated water to generate second treated water;
A method for operating an ultrapure water production apparatus, comprising: measuring the TOC concentration of the primary pure water before the ultraviolet oxidation step and controlling the amount of ultraviolet rays irradiated to the primary pure water based on the TOC concentration. .
In the primary water purification device, a second ultraviolet oxidation step is performed in which the water to be treated is irradiated with ultraviolet rays, and the TOC concentration of the water to be treated in this second ultraviolet oxidation step is measured, and and controlling the amount of ultraviolet irradiation, and in the secondary water purification device, after the platinum group metal catalyst resin treatment step, remove the dissolved gas in the second treated water to generate degassed water. and a deionization step to remove ionic impurities from this degassed water to generate third treated water, the dissolved oxygen concentration of the degassed water is At the same time, the TOC concentration of the third treated water is measured, and the amount of ultraviolet irradiation in the second ultraviolet oxidation step is determined based on the dissolved oxygen concentration and the TOC concentration in the third treated water. The method for operating an ultrapure water production apparatus according to claim 6, wherein the ultrapure water production apparatus is adjusted.
An ultrapure water production method in which treated raw water is processed with a primary water purification device to produce primary pure water, and this primary pure water is further processed with a secondary water purification device to produce secondary pure water, the method comprising:
In the secondary water purification device, a first ultraviolet oxidation step is performed in which the primary pure water is irradiated with ultraviolet rays to produce first treated water, and hydrogen peroxide in this first treated water is decomposed to produce a second treated water. a platinum group metal catalyst resin treatment step for producing treated water; and a degassing step for removing dissolved gas in the second treated water to generate degassed water after the platinum group metal catalyst resin treatment step; and a deionization step of removing ionic impurities from this degassed water to generate third treated water,
An ultrapure water production device comprising: measuring the TOC concentration of the third treated water; and controlling the output of the first ultraviolet oxidation device based on the TOC concentration of the third treated water. How to drive.
In the primary water purification apparatus, a second ultraviolet oxidation step is performed in which the treated object is irradiated with ultraviolet rays, and the TOC concentration of the treated water in this second ultraviolet oxidation step is measured to determine the amount of ultraviolet rays in the second ultraviolet oxidation step. In the secondary water purification device, the dissolved oxygen concentration of the degassed water is measured, and the TOC concentration of the third treated water is measured, and the dissolved oxygen concentration and 9. The method of operating an ultrapure water production apparatus according to claim 8, wherein the amount of ultraviolet ray irradiation in the second ultraviolet oxidation step is adjusted based on the TOC concentration of the third treated water.
The first ultraviolet oxidation step and the second ultraviolet oxidation step are performed using an ultraviolet oxidation device, and the ultraviolet oxidation device is composed of a plurality of blocks of ultraviolet lamps, and the illuminance of each ultraviolet lamp is controllable. 10. The method of operating an ultrapure water production apparatus according to claim 7, wherein the amount of ultraviolet irradiation is controlled by the number of operating blocks of the ultraviolet lamps and the illuminance of each ultraviolet lamp.