JP2009285574A - Water treatment apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a water treatment apparatus 1 which can supply a stable amount of pure water to external equipment without increasing an installation space. <P>SOLUTION: The water treatment apparatus 1 comprises a water storage tank 6 storing first treated water obtained by purifying water to be treated, a purification portion 7 purifying the first treated water supplied from the water storage tank 6 to obtain second treated water, a feed pump 8 connected to predetermined external equipment and supplying the first treated water and/or the second treated water to the predetermined external equipment, a connecting line 10d connecting the purification portion 7 to the feed pump 8, and an auxiliary line 10e connecting the connecting line 10d to the water storage tank 6. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a water treatment apparatus, and more particularly to a water treatment apparatus for obtaining high-purity pure water used for semiconductor cleaning and the like.

Conventionally, water that does not contain impurities, so-called pure water, is often used for cleaning semiconductors and the like. Generally, as a water treatment device for obtaining pure water from raw water such as industrial water, a reverse osmosis membrane device (RO device) using a reverse osmosis membrane, or an electric deionization using an ion exchange membrane and an ion exchange resin A device (EDI device) or the like is used. For example, the reverse osmosis membrane device uses the property of the reverse osmosis membrane that allows the solvent to pass but not the solute, and selectively passes only water as a solvent by applying a pressure higher than the osmotic pressure of the water to be treated. Can be collected (see, for example, Patent Document 1).
JP-A-5-220480

  By the way, in recent years, with the development of electronic technology such as semiconductors, pure water used as cleaning water has been required to have higher purity. In the reverse osmosis membrane device, the removal of ions in the raw water may be incomplete when the reverse osmosis membrane device alone is used. Therefore, for example, it may be necessary to selectively purify higher-purity pure water by further purifying the treated water obtained by purification using a reverse osmosis membrane device using an electric deionization device.

  In the electric deionization apparatus, a deionization chamber is configured by filling an ion exchange resin between stacked cation exchange membranes and anion exchange membranes. Therefore, the loss of pressure when passing water through the deionization chamber is high, and in order to supply a predetermined amount of water to an external device, for example, a water supply pump is provided on the downstream side of the electric deionization device. It is necessary to supply a predetermined flow rate from an electric deionizer to an external device. However, if the water supply pump is arranged downstream of the electric deionization device, for example, when the balance between the flow rate of the electric deionization device and the flow rate of the supply pump varies, the electric deionization arranged on the upstream side There was a risk of creating a back pressure on the ion exchange membrane of the apparatus. Or the feed water pump arrange | positioned downstream may become a negative pressure, and there also existed a possibility of generating cavitation.

  This can be avoided by installing a water storage tank on the downstream side of the electric deionizer, but if a new water storage tank is installed, for example, it is necessary to secure an installation space for the water storage tank. And there is a problem that it takes a great deal of cost to install a water storage tank. In addition, there is a problem that the carbon dioxide gas may be newly dissolved again by providing the water storage tank.

  Therefore, an object of the present invention is to provide a water treatment apparatus that can supply a stable amount of pure water to an external device without increasing the installation space.

  The water treatment apparatus of the present invention has a water storage tank for storing first treated water obtained by refining the water to be treated, and a purification for obtaining second treated water by refining the first treated water supplied from the water storage tank. A connection line for connecting the first treatment water and / or the second treatment water to the predetermined external device, and connecting the purification unit and the supply pump. And an auxiliary line for connecting the connection line and the water storage tank.

  Moreover, it is preferable that the said refinement | purification part performs the refinement | purification using an ion exchanger.

  The purification unit preferably performs purification using a reverse osmosis membrane.

  Moreover, it is preferable that a water treatment apparatus is further equipped with the return line which connects the said refinement | purification part and the said water storage tank, and returns the said 2nd treated water from the said refinement | purification part to the said water storage tank.

  The auxiliary line is preferably provided with a check valve for restricting the first treated water from flowing out of the water storage tank to the connection line.

  According to the present invention, the water treatment apparatus can supply a stable amount of pure water to an external device without increasing the installation space.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[1] First Embodiment FIG. 1 is a flow sheet showing a water treatment apparatus 1 according to a first embodiment of the present invention. As shown in FIG. 1, the water treatment device 1 according to the first embodiment includes an activated carbon filtration device 2, a soft water device 3, a water supply tank 4, a first reverse osmosis membrane device 5, a water storage tank 6, The system is mainly composed of a type deionizer (purification unit) 7 and a supply pump 8.

  The activated carbon filtration device 2 is connected to a source of raw water (not shown). The activated carbon filtering device 2 performs a filtering process on the raw water as the first purification process. Specifically, the activated carbon filtering device 2 obtains first pretreated water from raw water by adsorbing and removing an oxidizing agent such as sodium hypochlorite dissolved in the raw water. The activated carbon filter 2 is provided to prevent early deterioration of the ion exchange capacity of the water softener 3. The activated carbon filtration device 2 also serves to prevent early deterioration of the filtration capacity of the first reverse osmosis membrane device 5 and to improve and stabilize the treatment efficiency of the treated water.

  The soft water device 3 is connected to the downstream side of the activated carbon filtration device 2. The soft water device 3 performs a predetermined purification process on the first pretreated water obtained by the activated carbon filtration device 2. Specifically, the water softener 3 exchanges hardness components (calcium ions and magnesium ions) contained in the first pretreated water with sodium ions using an ion exchange resin. That is, the water softener 3 removes the hardness component from the first pretreated water to obtain the second pretreated water (treated water).

  The water supply tank 4 is connected to the downstream side of the water softener 3. The water supply tank 4 stores the second pretreated water purified by the water softener 3.

  The first reverse osmosis membrane device 5 is connected to the downstream side of the water supply tank 4 via the first supply line 10a. The first reverse osmosis membrane device 5 is mainly composed of a pressurizing pump 51 provided on the upstream side and a reverse osmosis module (hereinafter referred to as “RO module”) 52 provided on the downstream side. The pressurizing pump 51 pressurizes the second pretreated water supplied from the water supply tank 4 toward the RO module 52. The RO module 52 includes a large number of reverse osmosis membranes (not shown), and removes impurities by the reverse osmosis membranes. The 1st reverse osmosis membrane apparatus 5 obtains 1st pure water (1st process water) by selectively permeate | transmitting 2nd pre-treatment water.

  A distribution line 53 and a concentrated water drain line 54 are independently connected to the downstream side of the RO module 52. The first pure water from which impurities have been removed from the second pretreated water by the reverse osmosis membrane flows through the distribution line 53. From the concentrated water drain line 54, the concentrated waste water in which impurities of the second pretreatment water are concentrated by the reverse osmosis membrane of the RO module 52 is discharged.

  The water storage tank 6 is connected to the first reverse osmosis membrane device 5 through a water storage line 10b. The water storage line 10 b is connected to the downstream side of the distribution line 53 of the first reverse osmosis membrane device 5. The water storage tank 6 stores the first pure water purified by the first reverse osmosis membrane device 5.

  One side of the return line 55 is connected to the water storage line 10b in a form branched from the water storage line 10b. The other side of the return line 55 is connected to the water supply tank 4. The return line 55 connects the water storage line 10 b and the water supply tank 4.

  The electric deionizer 7 is connected to the water storage tank 6 through the second supply line 10c. The electric deionization apparatus 7 is mainly composed of a pressurizing pump 71 provided on the upstream side and a deionization module (hereinafter referred to as “EDI module”) 72 provided on the downstream side. The pressurizing pump 71 pressurizes the first pure water circulated from the water storage tank 6 toward the EDI module 72 side. The EDI module 72 is configured by filling an inside of a cation exchange membrane or anion exchange membrane (not shown) stacked with an ion exchanger. Impurities contained are removed. The EDI module 72 obtains second pure water (second treated water) from the first pure water by selectively allowing the first pure water to pass therethrough.

  Further, a distribution line 73 and a concentrated water drain line 74 are independently connected to the downstream side of the EDI module 72. The downstream side of the distribution line 73 is connected to the connection line 10d. The downstream side of the concentrated water drain line 74 is connected to the water supply tank 4. The second pure water from which impurities are removed from the first pure water by the ion exchange membrane flows through the distribution line 73. From the concentrated water drain line 74, the concentrated waste water in which impurities of the first pure water are concentrated by the reverse osmosis membrane is discharged. The concentrated wastewater is returned to the water supply tank 4 via the concentrated water drainage line 74 without being discarded.

  The supply pump 8 is connected in series with the electric deionization device 7 through a connection line 10d. Here, “in series” means that the electrical deionization device 7 and the supply pump 8 are connected without an intermediate tank or the like, for example. One side of the auxiliary line 10e is connected to the connection line 10d in a form branched from the connection line 10d. The other side of the auxiliary line 10 e is connected to the water storage tank 6. The auxiliary line 10 e connects the connection line 10 d and the water storage tank 6.

  In addition, one side of the return line 75 is connected to the connection line 10d in a form branched from the connection line 10d. The other side of the return line 75 is connected to the water storage tank 6. The return line 75 connects the connection line 10 d and the water storage tank 6.

  Next, operation | movement of the water treatment apparatus 1 which concerns on 1st Embodiment is demonstrated. The 1st pure water stored in the water storage tank 6 is refine | purified with the electrical deionization apparatus 7, and is suitably supplied to the external apparatus not shown. Therefore, the water storage amount of the water storage tank 6 decreases according to the supply amount to the external device. When the amount of water stored in the water storage tank 6 becomes less than a predetermined amount of water (predetermined water reduction level), an operation request is made to the water treatment device 1 of the first embodiment.

  When an operation request is made to the water treatment device 1 of the first embodiment, the water treatment device 1 of the first embodiment first activates the first reverse osmosis membrane device 5. When the first reverse osmosis membrane device 5 is activated, the first reverse osmosis membrane device 5 operates the pressurizing pump 51. When the pressurizing pump 51 is activated, the supply of the second pretreatment water from the water supply tank 4 is started. The second pretreated water is circulated to the first reverse osmosis membrane device 5 through the first supply line 10a. The second pretreated water circulated through the first reverse osmosis membrane device 5 is circulated to the RO module 52 by the pressurizing pump 51. The second pretreated water distributed to the RO module 52 is subjected to a predetermined purification process by the RO module 52. Thereby, the 2nd pretreatment water is refined and the 1st pure water is obtained.

  The first reverse osmosis membrane device 5 activated by the water treatment device 1 of the first embodiment is initially operated for a certain period of time until the purification capacity is stabilized. That is, the first reverse osmosis membrane device 5 first performs a first initial operation so as to obtain first pure water having a predetermined water quality. The first initial operation is performed for a predetermined time.

  The first pure water purified during the first initial operation may be returned to the water supply tank 4 via the return line 55 because there is a possibility that a predetermined water quality may not be obtained. That is, the first pure water purified during the first initial operation is circulated through the return line 55 during the first initial operation. Further, the concentrated wastewater discharged during the purification of the first pure water is discharged from the concentrated water drainage line 54 and discarded regardless of the first initial operation and the normal operation described later.

  When the first initial operation is completed, the water treatment device 1 of the first embodiment stores the first pure water in the water storage tank 6. When the amount of water stored in the water storage tank 6 exceeds a predetermined amount of water (a predetermined full water level), the water treatment device 1 of the first embodiment activates the electric deionization device 7. When the electric deionization device 7 is activated, the electric deionization device 7 first operates the pressurizing pump 71. When the pressurizing pump 71 is activated, the supply of the first pure water from the water storage tank 6 is started. The first pure water is circulated to the electric deionizer 7 through the second supply line 10c. The first pure water circulated through the electric deionizer 7 is circulated to the EDI module 72 by the pressurizing pump 71. The first pure water distributed to the EDI module 72 is subjected to a predetermined purification process by the EDI module 72. Thereby, 1st pure water is refine | purified and 2nd pure water is obtained.

  The electric deionizer 7 activated by the water treatment device 1 of the first embodiment performs an initial operation for a certain period of time until the purification capacity is stabilized. That is, the water treatment apparatus 1 of the first embodiment causes the electric deionization apparatus 7 to perform the second initial operation so as to obtain a predetermined water quality. The second initial operation is performed for a predetermined time.

  The second pure water purified during the second initial operation may be returned to the water storage tank 6 via the return line 75 because there is a possibility that the predetermined water quality may not be obtained. That is, the second pure water purified during the second initial operation is circulated through the return line 75 during the second initial operation.

  Moreover, since the concentrated waste water discharged | emitted at the time of refinement | purification of 2nd pure water is what concentrated 1st pure water, it is a thing with a higher purification degree than 2nd pre-treatment water. Thereby, the concentrated wastewater discharged during the purification of the second pure water is returned to the water supply tank 4 through the concentrated water drainage line 74. That is, the concentrated wastewater discharged during the purification of the first pure water is circulated through the concentrated water drainage line 74.

  When the second initial operation of the electric deionization device 7 is completed, the water treatment device 1 of the first embodiment starts the supply pump 8. That is, the water treatment apparatus 1 of the first embodiment starts supplying the second pure water to the external device.

  In the case where an operation request is made when the water storage tank 6 has a water storage amount greater than or equal to a predetermined amount, first, the above operation in the electric deionizer 7 is prioritized, and the second pure water to the external device is given priority. Supply. Then, when the amount of water stored in the water storage tank 6 becomes less than a predetermined amount, the first reverse osmosis membrane device 5 is activated and the above operation is performed.

  In addition, when the first pure water is stored in the water storage tank 6 in advance and a predetermined time has elapsed, carbon dioxide gas or the like may be re-dissolved in the first pure water. Therefore, the water treatment apparatus 1 of 1st Embodiment starts the electric deionization apparatus 7 with progress of predetermined time after water storage of 1st pure water. In this case, the water treatment device 1 of the first embodiment causes the electric deionization device 7 to perform an operation similar to the second initial operation described above. That is, the water treatment device 1 purifies the first pure water stored in the water storage tank 6 for a predetermined time into the second pure water by the electric deionization device 7. And the 2nd pure water refine | purified by the electric deionization apparatus 7 is returned to the water storage tank 6 via the auxiliary line 10e, and is stored. At the time of start-up, the water treatment apparatus 1 always monitors the storage time of the first pure water and repeats the above operation.

  According to the water treatment device 1 of the first embodiment having the above configuration, the following effects are obtained. An electrical deionization device 7 is connected to the water treatment device 1 of the first embodiment via a water storage tank 6 on the downstream side of the first reverse osmosis membrane device 5. The electric deionizer 7 is connected in series with the supply pump 8. Therefore, in the water treatment device 1 of the first embodiment, it is possible to supply the second pure water with little re-dissolution such as carbon dioxide gas to the external device.

  Furthermore, the water treatment apparatus 1 of the first embodiment is provided with an auxiliary line 10e that connects the connection line 10d and the water storage tank 6. Therefore, in the water treatment device 1 of the first embodiment, the second pure water purified by the electric deionization device 7 can be circulated through the water storage tank 6. Thereby, in the water treatment apparatus 1 of 1st Embodiment, it becomes possible to prevent re-dissolution of carbon dioxide etc. of the 1st pure water stored in the water storage tank 6. FIG.

  Further, in the water treatment apparatus 1 of the first embodiment, even when the supply pump 8 needs to supply the second pure water that exceeds the treatment capacity of the electric deionization apparatus 7, the water is stored via the auxiliary line 10e. The first pure water and / or the circulated second pure water can be supplied from the tank 6 to the supply pump 8. Therefore, in the water treatment device 1 of the first embodiment, it is possible to stably supply a necessary amount of pure water to an external device. Further, in the water treatment device 1 of the first embodiment, the back pressure generated in the ion exchange membrane of the electric deionization device 7 resulting from the flow rate balance between the supply pump 8 and the electric deionization device 7, and the supply pump 8 It becomes possible to prevent the negative pressure which arises. That is, breakage of the ion exchange membrane of the electric deionizer 7 and cavitation of the water supply pump 8 can be avoided. Thereby, in the water treatment apparatus 1 of 1st Embodiment, it becomes unnecessary to provide the intermediate tank etc. which store the 2nd treated water temporarily in the downstream of the electric deionization apparatus 7. FIG.

  Moreover, the water treatment apparatus 1 of 1st Embodiment is provided with the return line 55 which connects the water storage line 10b and the water supply tank 4. FIG. Therefore, in the water treatment device 1 of the first embodiment, it is possible to return the first pure water purified during the first initial operation to the water supply tank 4. Thereby, in the water treatment device 1 of the first embodiment, for example, the second pretreatment water stored in the water supply tank 4 can be diluted with the first pure water and stored in the water supply tank 4. It becomes possible to improve the quality of the second pretreated water. Moreover, the water treatment apparatus 1 according to the first embodiment can effectively use the first pure water.

  Further, in the water treatment apparatus 1 of the first embodiment, the concentrated drainage discharged at the time of purification of the second pure water by the electric deionizer 7 is not discarded and is supplied to the water supply tank 4 via the concentrated water drainage line 74. return. Therefore, the water treatment device 1 of the first embodiment can effectively use the concentrated drainage.

  Moreover, the water treatment apparatus 1 of 1st Embodiment is provided with the return line 75 which returns the 2nd pure water refine | purified at the time of the 2nd initial operation of the electric deionization apparatus 7 to the water supply tank 4. FIG. Therefore, the water treatment device 1 of the first embodiment can effectively use the second pure water.

[2] Second Embodiment FIG. 2 is a flow sheet showing a water treatment apparatus according to a second embodiment of the present invention. As shown in FIG. 2, the water treatment device 1A according to the second embodiment includes an activated carbon filtration device 2, a soft water device 3, a water supply tank 4, a first reverse osmosis membrane device 5, a water storage tank 6, and a first 2 Consists mainly of a reverse osmosis membrane device (purification unit) 9 and a supply pump 8. The water treatment apparatus 1A according to the second embodiment is mainly different from the first embodiment in that a second reverse osmosis membrane device 9 is provided instead of the electric deionization device 7.

  Hereinafter, a description will be given centering on differences from the first embodiment. In the following embodiments, parts that are not particularly described are the same as those in the first embodiment, and the same reference numerals are given to the numbers given in the drawings if they are the same as those in the first embodiment.

  The second reverse osmosis membrane device 9 is connected to the downstream side of the water storage tank 6 via the second supply line 10c. The second reverse osmosis membrane device 9 is mainly composed of a pressure pump 91 provided on the upstream side and a reverse osmosis module (hereinafter referred to as RO module) 92 provided on the downstream side. The pressurizing pump 91 pressurizes the first pure water circulated from the water storage tank 6 toward the RO module 92. The RO module 92 includes a large number of reverse osmosis membranes (not shown), and removes impurities by the reverse osmosis membranes. The second reverse osmosis membrane device 9 obtains third pure water (second treated water) from the first pure water by selectively allowing the first pure water to permeate.

  In addition, a distribution line 93 and a concentrated water drain line 94 are connected to the RO module 92. The downstream side of the distribution line 93 is connected to the connection line 10d. The downstream side of the concentrated water drain line 94 is connected to the water supply tank 4. The third pure water from which impurities are removed from the first pure water by the reverse osmosis membrane flows through the distribution line 93. From the concentrated water drainage line 94, the concentrated wastewater in which impurities of the first pure water are concentrated by the reverse osmosis membrane is discharged. The concentrated wastewater concentrated by the second reverse osmosis membrane device 9 is returned to the water supply tank 4 via the concentrated water drainage line 94 without being discarded.

  The supply pump 8 is connected in series to the downstream side of the second reverse osmosis membrane device 9 via a connection line 10d. Here, “in series” means that the second reverse osmosis membrane device 9 and the supply pump 8 are connected without an intermediate tank or the like, for example. One side of the auxiliary line 10e is connected to the connection line 10d in a form branched from the connection line 10d. The other side of the auxiliary line 10 e is connected to the water storage tank 6. The auxiliary line 10 e connects the connection line 10 d and the water storage tank 6.

  In addition, one side of the return line 75 is connected to the connection line 10d in a form branched from the connection line 10d. The other side of the return line 75 is connected to the water storage tank 6. The return line 75 connects the connection line 10 d and the water storage tank 6.

  Next, operation | movement of 1 A of water treatment apparatuses of 2nd Embodiment is demonstrated. The 1st pure water stored in the water storage tank 6 is refine | purified with the 2nd reverse osmosis membrane apparatus 9, and is suitably supplied to the external apparatus not shown. Therefore, the water storage amount of the water storage tank 6 decreases according to the supply amount to the external device. When the amount of water stored in the water storage tank 6 becomes less than a predetermined amount of water (predetermined water reduction level), an operation request is made to the water treatment device 1A of the second embodiment.

  When an operation request is made to the water treatment device 1A of the second embodiment, first, the water treatment device 1A of the second embodiment activates the first reverse osmosis membrane device 5. When the first reverse osmosis membrane device 5 is activated, the first reverse osmosis membrane device 5 operates the pressurizing pump 51. When the pressurizing pump 51 is activated, the supply of the second pretreatment water from the water supply tank 4 is started. The second pretreated water is circulated to the first reverse osmosis membrane device 5 through the first supply line 10a. The second pretreated water circulated through the first reverse osmosis membrane device 5 is circulated to the RO module 52 by the pressurizing pump 51. The second pretreated water distributed to the RO module 52 is subjected to a predetermined purification process by the RO module 52. Thereby, the 2nd pretreatment water is refined and the 1st pure water is obtained.

  The first reverse osmosis membrane device 5 activated by the water treatment device 1A of the second embodiment is initially operated for a certain period of time until the purification capacity is stabilized. That is, the first reverse osmosis membrane device 5 first performs a first initial operation so as to obtain first pure water having a predetermined water quality. The first initial operation is performed for a predetermined time.

  The first pure water purified during the first initial operation may be returned to the water supply tank 4 via the return line 55 because there is a possibility that a predetermined water quality may not be obtained. That is, the first pure water purified during the first initial operation is circulated through the return line 55 during the first initial operation. Further, the concentrated wastewater discharged during the purification of the first pure water is discharged from the concentrated water drainage line 54 and discarded regardless of the first initial operation and the normal operation described later.

  When the first initial operation is completed, the water treatment device 1 </ b> A of the second embodiment stores the first pure water in the water storage tank 6. When the amount of water stored in the water storage tank 6 becomes equal to or greater than a predetermined amount of water (a predetermined full water level), the water treatment device 1A of the second embodiment activates the second reverse osmosis membrane device 9. When the second reverse osmosis membrane device 9 is activated, the second reverse osmosis membrane device 9 first operates the pressurizing pump 91. When the pressurizing pump 91 is operated, the supply of the first pure water from the water storage tank 6 is started. The first pure water is circulated to the second reverse osmosis membrane device 9 via the second supply line 10c. The first pure water circulated through the second reverse osmosis membrane device 9 is circulated to the RO module 92 by the pressurizing pump 91. The first pure water circulated through the RO module 92 is subjected to a predetermined purification process by the RO module 92. Thereby, 1st pure water is refine | purified and 3rd pure water is obtained.

  The second reverse osmosis membrane device 9 activated by the water treatment device 1A of the second embodiment performs an initial operation for a certain period of time until the purification capacity is stabilized. That is, the water treatment apparatus 1A of the second embodiment causes the second reverse osmosis membrane apparatus 9 to perform the third initial operation so that a predetermined water quality is obtained. The third initial operation is performed for a predetermined time.

  The third pure water purified during the third initial operation may be returned to the water storage tank 6 via the return line 95 because there is a possibility that a predetermined water quality may not be obtained. That is, the third pure water purified during the third initial operation is circulated through the return line 95 during the third initial operation.

  Moreover, since the concentrated waste water discharged | emitted at the time of refinement | purification of 3rd pure water is what concentrated 1st pure water, it is a thing with a higher purification degree than 2nd pre-treatment water. Thereby, it returns to the water supply tank 4 through the concentrated water drainage line 94. That is, the concentrated waste water discharged during the purification of the first pure water is circulated through the concentrated water drain line 94.

  When the third initial operation of the second reverse osmosis membrane device 9 is completed, the water treatment device 1A of the second embodiment activates the supply pump 8. That is, the water treatment apparatus 1A of the second embodiment starts supplying the third pure water to the external device.

  In the case where an operation request is made when the water storage tank 6 has a water storage amount greater than or equal to a predetermined amount, first, the above operation in the second reverse osmosis membrane device 9 is prioritized, and the third pure water is supplied to the external device. Supply. Then, when the amount of water stored in the water storage tank 6 becomes less than a predetermined amount, the first reverse osmosis membrane device 5 is activated and the above operation is performed.

  In addition, when the first pure water is stored in the water storage tank 6 in advance and a predetermined time has elapsed, carbon dioxide gas or the like may be re-dissolved in the first pure water. Therefore, 1 A of water treatment apparatuses of 2nd Embodiment start the 2nd reverse osmosis membrane apparatus 9 with progress of predetermined time after water storage of 1st pure water. In this case, the water treatment device 1A of the second embodiment causes the second reverse osmosis membrane device 9 to perform the same operation as the above-described third initial operation. That is, the water treatment apparatus 1A of the second embodiment purifies the first pure water stored in the water storage tank 6 for a predetermined time into the third pure water by the second reverse osmosis membrane apparatus 9. And the 3rd pure water refine | purified by the 2nd reverse osmosis membrane apparatus 9 is returned to the water storage tank 6 via the auxiliary line 10e, and is stored. The water treatment apparatus 1A of the second embodiment always monitors the water storage time of the first pure water at the time of startup and repeats the above operation.

  According to the water treatment device 1 of the second embodiment having the above configuration, the following effects are obtained. A second reverse osmosis membrane device 9 is connected to the water treatment device 1 </ b> A of the second embodiment via a water storage tank 6 on the downstream side of the first reverse osmosis membrane device 5. The second reverse osmosis membrane device 9 is connected in series with the supply pump 8. Therefore, in the water treatment apparatus 1 of the second embodiment, it is possible to supply the third device with the third pure water with little re-dissolution such as carbon dioxide gas to the external device.

  Further, the water treatment apparatus 1 </ b> A of the second embodiment is provided with an auxiliary line 10 e that connects the connection line 10 d and the water storage tank 6. Therefore, in the water treatment apparatus 1A of the second embodiment, the third pure water purified by the second reverse osmosis membrane apparatus 9 can be circulated through the water storage tank 6. Thereby, in the water treatment apparatus 1A of the second embodiment, it is possible to prevent re-dissolution of carbon dioxide gas or the like of the first pure water stored in the water storage tank 6.

  In addition, in the water treatment apparatus 1A of the second embodiment, even when the supply pump 8 needs to supply third pure water that exceeds the processing capacity of the second reverse osmosis membrane apparatus 9, the auxiliary line 10e is used. The first pure water and / or the third pure water that circulates from the water storage tank 6 can be supplied to the supply pump 8. Therefore, in the water treatment apparatus 1A of the second embodiment, it is possible to stably supply a necessary amount of pure water to an external device. Further, in the water treatment apparatus 1A of the second embodiment, the back pressure generated in the reverse osmosis membrane of the second reverse osmosis membrane device 9 resulting from the flow rate balance between the supply pump 8 and the second reverse osmosis membrane device 9, and the supply pump It becomes possible to prevent the negative pressure generated in FIG. That is, the reverse osmosis membrane of the second reverse osmosis membrane 9 and the cavitation of the water supply pump 8 can be avoided. Thereby, in the water treatment apparatus 1A of the second embodiment, it is not necessary to provide an intermediate tank or the like for temporarily storing the third treated water on the downstream side of the second reverse osmosis membrane apparatus 9.

  Moreover, the return line 55 which connects the water storage line 10b and the water supply tank 4 is provided in 1 A of water treatment apparatuses of 2nd Embodiment. Therefore, in the water treatment apparatus 1 </ b> A of the second embodiment, it is possible to return the first pure water purified during the first initial operation to the water supply tank 4. Thereby, in the water treatment apparatus 1A of the second embodiment, for example, the second pretreated water stored in the water supply tank 4 can be diluted with the first pure water and stored in the water supply tank 4. It becomes possible to improve the quality of the second pretreated water. Moreover, the water treatment apparatus 1A of the second embodiment can effectively use the first pure water.

  Further, in the water treatment apparatus 1A of the second embodiment, the water supply tank 4 is disposed via the concentrated water drain line 94 without discarding the concentrated drainage discharged during the purification of the third pure water by the second reverse osmosis membrane apparatus 9. Return to. Therefore, the water treatment apparatus 1A of the second embodiment can effectively use concentrated waste water.

  Further, the water treatment apparatus 1A of the second embodiment is provided with a return line 95 for returning the third pure water purified during the third initial operation of the second reverse osmosis membrane apparatus 9 to the water supply tank 4. Therefore, the water treatment apparatus 1A of the second embodiment can effectively use the second pure water.

  In addition, embodiment of this invention is not limited to said embodiment at all, and the technical scope of this invention is not limited to this.

  For example, in the first embodiment, the auxiliary line 10e is directly connected to the connection line 10d. However, the present invention is not limited to this. A check valve that restricts the flow direction of the second pure water and / or the third pure water in the auxiliary line 10e only in the direction from the connection line 10d toward the water storage tank 6 may be provided in the auxiliary line 10e. By restricting the flow direction of the first pure water and / or the third pure water in the auxiliary line 10e only to the direction from the connection line 10d toward the water storage tank 6, the first pure water and / or the third pretreated water is stored. It is possible to prevent direct distribution from the tank 6 to the electric deionization device 7. Therefore, the second pure water and / or the third pure water are always circulated through the supply pump 8 via the electric deionizer 7. Thereby, it becomes possible to supply high purity 2nd pure water and / or 3rd pure water to an external apparatus.

  In the embodiment, the initial operation of the first reverse osmosis membrane device 5, the electric deionization device 7 and / or the second reverse osmosis membrane device 9 is configured to be canceled after a predetermined time. The invention is not limited to this. For example, a water quality meter may be provided in the return line 55 and the return line 75 and the initial operation may be canceled on condition that the first pure water, the second pure water, and the like have a predetermined water quality.

  Moreover, although the said embodiment demonstrated as a water treatment apparatus which supplies a pure water to the external apparatus which wash | cleans a semiconductor, in this invention, it is not restricted to this. For example, as an external device, you may use for the water treatment apparatus which supplies pure water to thermal equipment, such as a steam boiler, a hot water boiler, a cooling tower, and a water heater.

It is a flow sheet which shows the water treatment equipment concerning a 1st embodiment of the present invention. It is a flow sheet which shows the water treatment equipment concerning a 2nd embodiment of the present invention.

Explanation of symbols

1, 1A Water treatment device 6 Water storage tank 7 Electric deionization device 8 Supply pump 10d Connection line 10e Auxiliary line

Claims (5)

A water storage tank for storing first treated water obtained by refining treated water;
A purification unit for refining the first treated water supplied from the water storage tank to obtain the second treated water;
A supply pump that is connected to a predetermined external device and supplies the first treated water and / or the second treated water to the predetermined external device;
A connection line connecting the purification unit and the supply pump;
A water treatment apparatus comprising: an auxiliary line for connecting the connection line and the water storage tank.   The water treatment apparatus according to claim 1, wherein the purification unit performs purification using an ion exchanger.   The water treatment apparatus according to claim 1, wherein the purification unit performs purification using a reverse osmosis membrane.   The water treatment according to any one of claims 1 to 3, further comprising a return line that connects the purification unit and the water storage tank and returns the second treated water from the purification unit to the water storage tank. apparatus.   The water treatment apparatus according to any one of claims 1 to 4, wherein the auxiliary line is provided with a check valve that restricts the first treated water from flowing out of the water storage tank to the connection line.

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