Water treatment method, water treatment apparatus, and water treatment system

Abstract

The present invention provides a water treatment method that can improve the purity of water used for purposes other than scrubber water supplied to exhaust gas treatment equipment, or water supplied to ancillary equipment installed around exhaust gas treatment equipment. [Solution] The water treatment method is characterized by comprising: a desalination treatment step of further desalination treatment of a portion of the desalination treated water supplied as scrubber water to the exhaust gas treatment equipment 14 that treats exhaust gas, by a desalination equipment 30; and a treated water supply step of supplying the treated water after the desalination treatment step to the exhaust gas treatment equipment 14 or a first ancillary equipment installed around the exhaust gas treatment equipment as water to be used for purposes other than the scrubber water, or to a second ancillary equipment installed around the exhaust gas treatment equipment 14 for treating the exhaust gas.

Description

Technical Field

[0001] The present disclosure relates to the technology of water treatment methods, water treatment devices, and water treatment systems.

Background Art

[0002] In order to detoxify harmful gases including HF, NH3, etc. discharged from semiconductor factories and the like, exhaust gas treatment equipment (so-called decontamination devices) is used. In the exhaust gas treatment equipment, treatments such as absorbing and detoxifying harmful components in the exhaust gas with scrubber water, reducing the concentration of harmful components in the exhaust gas, and cooling the exhaust gas are performed. In the exhaust gas treatment equipment, from the viewpoints of cost and water resource conservation, the scrubber water mainly uses desalinated water obtained by desalinating the drainage discharged from the exhaust gas treatment equipment with an RO membrane or the like and recovering it. However, the desalinated water is water with a water quality that is not very high (not pure water), about 200 μS / cm. For example, Patent Document 1 discloses a technique for treating the drainage discharged from the exhaust gas treatment equipment and recovering it as scrubber water. However, the required water quality of the scrubber water may be at the tap water level, and it is preferably soft water or RO-treated water for industrial use.

[0003] In the exhaust gas treatment equipment, there are cases where clear water is required other than for the use of scrubber water. Also, clear water is required for the water supplied to the auxiliary equipment installed around the exhaust gas treatment equipment for purifying the exhaust gas. However, conventionally, clear water has not been used for water used for purposes other than the scrubber water of the exhaust gas treatment equipment or for water supplied to the auxiliary equipment.

[0004] For example, Patent Document 2 discloses a technology for reducing harmful components such as PFCs (perfluorocompounds) contained in exhaust gas discharged from an exhaust gas treatment facility by supplying hydrogen gas to the exhaust gas. The proposed method for generating this hydrogen gas is by using a device that generates hydrogen gas by electrolyzing water. This device is an ancillary facility surrounding the exhaust gas treatment facility, and while it is preferable to use clear water (e.g., pure water) for electrolysis, conventionally, it has not been possible to supply clear water to such a device. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2022-070609 [Patent Document 2] Special Publication No. 2023-547670 [Overview of the project] [Problems that the invention aims to solve]

[0006] The purpose of this disclosure is to provide a water treatment method, a water treatment apparatus, and a water treatment system that can improve the purity of water used for purposes other than scrubber water supplied to an exhaust gas treatment facility, or water supplied to ancillary equipment installed around an exhaust gas treatment facility. [Means for solving the problem]

[0007] Furthermore, a water treatment apparatus according to one aspect of the present disclosure is characterized by comprising: a desalination water line that supplies desalination water as scrubber water to an exhaust gas treatment facility that treats exhaust gas; a water supply line that branches off from the desalination water line and carries a portion of the desalination water; a desalination facility that further desalinates a portion of the desalination water supplied by the water supply line; and a treated water line A that supplies the treated water desalinized by the desalination facility to the exhaust gas treatment facility or a first ancillary facility installed around the exhaust gas treatment facility as water to be used for purposes other than the scrubber water, or a treated water line B that supplies the treated water to a second ancillary facility installed around the exhaust gas treatment facility for treating the exhaust gas.

[0008] Furthermore, in the water treatment apparatus, it is preferable that the electrical conductivity of the treated water desalinated by the desalination equipment is 10 μS / cm or less.

[0009] Furthermore, in the water treatment apparatus, it is preferable that the desalination equipment includes an EDI device.

[0010] Furthermore, in the water treatment apparatus, it is preferable that the desalination equipment is installed in the same building as the exhaust gas treatment equipment.

[0011] Furthermore, in the water treatment apparatus, it is preferable that the desalination equipment is integrated into the exhaust gas treatment equipment as a unit.

[0012] Furthermore, in the water treatment apparatus, the first ancillary equipment is preferably a chemical solution manufacturing apparatus.

[0013] Furthermore, in the water treatment apparatus, it is preferable that the second ancillary equipment includes a water electrolysis hydrogen generator that generates hydrogen gas by electrolyzing water, and has a hydrogen gas line that supplies the hydrogen gas generated by supplying treated water, which has been desalted by the desalination equipment, to the water electrolysis hydrogen generator via the treated water line B, to the exhaust gas treated by the exhaust gas treatment equipment or the gas treated by the exhaust gas treatment equipment.

[0014] Furthermore, in the water treatment apparatus, the wastewater discharged from the desalination equipment is used to supply the scrubber water to the exhaust gas treatment equipment. The aforementioned desalination treatment water line It is preferable to have a return line for returning the product.

[0015] Furthermore, a water treatment system according to one aspect of this disclosure is characterized by comprising the water treatment device and the exhaust gas treatment equipment.

[0016] Furthermore, a water treatment method according to one aspect of this disclosure includes step A of supplying desalination treated water as scrubber water to an exhaust gas treatment facility that treats exhaust gas, The desalination treated water is branched A portion of the desalination treatment water obtain Process B, and in the aforementioned process B obtained The system is characterized by comprising: a desalination treatment step of further desalination treatment of a portion of the desalination treated water using a desalination facility; a treated water supply step of supplying the treated water after the desalination treatment step to the exhaust gas treatment facility or a first ancillary facility installed around the exhaust gas treatment facility as water to be used for purposes other than the scrubber water, or a treated water supply step of supplying the treated water to a second ancillary facility installed around the exhaust gas treatment facility for treating the exhaust gas. [Effects of the Invention]

[0017] According to this disclosure, it is possible to provide a water treatment method, a water treatment apparatus, and a water treatment system that can improve the purity of water used for purposes other than scrubber water supplied to exhaust gas treatment equipment, and / or water supplied to ancillary equipment installed around exhaust gas treatment equipment. [Brief explanation of the drawing]

[0018] [Figure 1] This is a schematic diagram showing an example of a water purification system equipped with a water treatment device according to this embodiment. [Figure 2] This is a schematic diagram showing another example of a water purification system equipped with the water treatment device according to this embodiment. [Figure 3] This is a schematic diagram showing another example of a water purification system equipped with the water treatment device according to this embodiment. [Figure 4] It is a schematic diagram showing another example of a purification system including the water treatment apparatus according to the present embodiment.

Embodiments for Carrying Out the Invention

[0019] Embodiments of the present disclosure will be described below. This embodiment is an example of implementing the present disclosure, and the present disclosure is not limited to this embodiment.

[0020] FIG. 1 is a schematic diagram showing an example of a purification system including the water treatment apparatus according to the present embodiment. The purification system 1 shown in FIG. 1 includes a water treatment system 2 including a water treatment apparatus 10 and an exhaust gas purification apparatus 12.

[0021] The exhaust gas purification apparatus 12 is an apparatus for treating exhaust gas discharged from a semiconductor factory or the like, and its configuration is not particularly limited. For example, as shown in FIG. 1, it has an exhaust gas treatment facility 14, an exhaust gas inflow line 16, a desalinated treated water line 18 which is a scrubber water line, a gas discharge line 20, a drainage discharge line 22, a circulation line 24, a circulation pump 26, and fluid nozzles 28a and 28b. The exhaust gas treatment facility 14 has a gas-liquid contact part 14a and a storage part 14b. The gas-liquid contact part 14a shown in FIG. 1 is a flow path through which the exhaust gas meanders and flows. Although not shown in the figure, the exhaust gas treatment facility 14 is provided with a gas inlet, a water supply port, a gas outlet, and a circulation inlet disposed on the side of the gas-liquid contact part 14a. The exhaust gas inflow line 16 is connected to the gas inlet, one end of the desalinated treated water line 18 is connected to the water supply port, the gas discharge line 20 is connected to the gas outlet, and one end of the circulation line 24 is connected to the circulation inlet. Further, although not shown in the figure, the exhaust gas treatment facility 14 is provided with a drainage port and a circulation outlet disposed on the side of the storage part 14b. One end of the drainage discharge line 22 is connected to the drainage port, and the other end of the circulation line 24 is connected to the circulation outlet.

[0022] Fluid nozzles 28a and 28b are provided within the gas-liquid contact section 14a. Fluid nozzle 28a is connected to the desalination treatment water line 18, and fluid nozzle 28b is connected to the circulation line 24. A circulation pump 26 is installed in the circulation line 24.

[0023] The water treatment device 10 comprises a desalination plant 30, a water supply line 32, a treated water line 34 (treated water line A), and a drainage line 36. One end of the water supply line 32 is connected to the desalination treated water line 18, and the other end is connected to the drainage inlet (not shown) of the desalination plant 30. One end of the treated water line 34 is connected to the treated water outlet (not shown) of the desalination plant 30, and the other end is connected to a supply port (not shown) provided in the exhaust gas treatment plant 14. One end of the drainage line 36 is connected to the drainage outlet (not shown) of the desalination plant 30, and the other end is connected to a supply port (not shown) provided on the storage section 14b side of the exhaust gas treatment plant 14.

[0024] The desalination equipment 30 is equipment for desalination treatment of the target wastewater, and examples include an RO device equipped with a reverse osmosis membrane, an ion exchange device equipped with an ion exchange resin, and an EDI device. The EDI device is an electro-regenerative deionization device that obtains treated water from which ions have been removed from the target wastewater by electro-regenerative desalination and wastewater with an increased ion content. These devices may be used individually or in combination. The RO device, ion exchange device, and EDI device may each be conventionally known devices, and their specific configurations are not particularly limited. The target wastewater is desalination treated water supplied to the exhaust gas treatment equipment 14 as scrubber water (hereinafter sometimes referred to as the first desalination treated water). The desalination equipment 30 may further include devices equipped with activated carbon filters, microfiltration membranes, ultrafiltration membranes, activated carbon devices, water softeners, ultraviolet sterilization devices, etc., as needed.

[0025] The purification system 1 shown in Figure 1 includes a wastewater recovery system 3. The wastewater recovery system 3 is installed, for example, in a building separate from the building where the water treatment system 2 is installed, or outdoors. The wastewater recovery system 3 is a system that desalinates wastewater discharged from the exhaust gas treatment facility 14 and recovers it as scrubber water for the exhaust gas treatment facility 14. The wastewater recovery system 3 shown in Figure 1 includes at least a wastewater desalination facility 38 and a first desalination treated water tank 40. One end of the desalination treated water line 42 is connected to the treated water outlet (not shown) of the wastewater desalination facility 38, and the other end is connected to the inlet (not shown) of the first desalination treated water tank 40. Examples of wastewater desalination facilities 38 include RO devices equipped with reverse osmosis membranes, ion exchange devices equipped with ion exchange resins, EDI devices, etc. These devices may be used individually or in combination. In the desalination treatment of the wastewater desalination equipment 38, a first desalination treatment water is obtained, for example, with an electrical conductivity of about 200 μS / cm (for example, about 180-200 μS / cm). The first desalination treatment water is stored in the first desalination treatment water tank 40. The other end of the aforementioned desalination treatment water line 18 is connected to the outlet (not shown) of the first desalination treatment water tank 40.

[0026] The operation of the purification system 1 shown in Figure 1 will be explained.

[0027] Exhaust gas is supplied to the gas-liquid contact section 14a of the exhaust gas treatment equipment 14 through the exhaust gas inlet line 16, and the first desalination water in the first desalination water tank 40 is supplied to the exhaust gas treatment equipment 14 as scrubber water through the desalination water line 18 (process A). The scrubber water is sprayed into the gas-liquid contact section 14a from the fluid nozzle 28a. Inside the gas-liquid contact section 14a, the exhaust gas and the scrubber water sprayed from the fluid nozzle 28a come into gas-liquid contact. The exhaust gas or the treated gas after gas-liquid contact may be heated as needed. In addition, the scrubber water supplied to the gas-liquid contact section 14a is stored in the storage section 14b of the exhaust gas treatment equipment 14, and the scrubber water stored in the storage section 14b is sprayed into the gas-liquid contact section 14a from the fluid nozzle 28b through the circulation line 24 by the operation of the circulation pump 26. Within the gas-liquid contact section 14a, the scrubber water sprayed from the fluid nozzle 28b and the exhaust gas flowing through the gas-liquid contact section 14a come into gas-liquid contact. Through this gas-liquid contact between the exhaust gas and the scrubber water, particulate matter and harmful components (e.g., ammonia, PFCs, NOx, etc.) in the exhaust gas are absorbed by the scrubber water and rendered harmless, or their concentration is reduced, and the exhaust gas is cooled.

[0028] Furthermore, in the purification system 1 shown in Figure 1, a portion of the first desalination treatment water passing through the desalination treatment water line 18 is passed through the water supply line 32 (process B). The desalination treatment water passing through the water supply line 32 is supplied to the desalination equipment 30 and desalinates (desalination treatment process). Through the desalination treatment by the desalination equipment 30, the first desalination treatment water is separated into treated water with a reduced concentration of impurity ions and wastewater with an increased concentration of impurity ions. In this way, by further desalination treatment of the desalination treatment water, highly pure treated water (hereinafter sometimes referred to as second desalination treatment water) can be obtained. In the desalination treatment by the desalination equipment 30, for example, second desalination treatment water with an electrical conductivity of 10 μS / cm or less can be obtained.

[0029] The second desalination water obtained from the desalination equipment 30 is supplied to the exhaust gas treatment equipment 14 through the treated water line 34 and used as water for the exhaust gas treatment equipment 14. The water for the exhaust gas treatment equipment may be supplied to the exhaust gas treatment equipment 14 for use as water for the scrubber of the exhaust gas treatment equipment 14, or it may be supplied to the exhaust gas treatment equipment 14 as water for a purpose other than that of the scrubber of the exhaust gas treatment equipment 14 (treated water supply process). When the treated water is used as water for the scrubber of the exhaust gas treatment equipment 14, for example, a fluid nozzle (not shown) is installed at the other end of the treated water line 34, and the second desalination water (scrubber water) is sprayed from the fluid nozzle into the gas-liquid contact section 14a, bringing it into gas-liquid contact with the exhaust gas passing through the gas-liquid contact section 14a. Since the second desalination water is highly purified water, harmful components in the exhaust gas can be efficiently reduced. Furthermore, the second desalination treatment water can be used for purposes other than the scrubber water of the exhaust gas treatment equipment 14, such as cleaning the inside of the exhaust gas treatment equipment 14. For example, the second desalination treatment water passing through the treatment water line 34 is sprayed toward the inner wall of the exhaust gas treatment equipment 14, dissolving or dispersing any solid matter adhering to the inner wall, thereby cleaning the inside of the exhaust gas treatment equipment 14. The second desalination treatment water is preferably pure water with an conductivity of approximately 10 μS / cm or less, preferably 1 μS / cm or less. If impure water is supplied, the removal of solid matter adhering to the inner wall of the exhaust gas treatment equipment 14 may be insufficient. The wastewater discharged by the desalination equipment 30 may be discharged outside the system, or it may be supplied to the storage section 14b from the wastewater line 36.

[0030] The exhaust gas is treated in the gas-liquid contact section 14a and then discharged as treated gas from the gas discharge line 20. In addition, a portion of the water stored in the storage section 14b is periodically discharged as wastewater from the wastewater discharge line 22 and supplied to the wastewater desalination equipment 38 for desalination treatment. The desalination-treated water (conductivity of approximately 200 μS / cm) treated by the wastewater desalination equipment 38 passes through the desalination-treated water line 42 and is stored in the first desalination-treated water tank 40. The recovery rate of desalination-treated water in the wastewater recovery system 3 (amount of desalination-treated water / amount of wastewater discharged from the wastewater desalination equipment × 100) is generally 90-96%, so it is preferable to periodically supply the first desalination-treated water tank 40 with approximately 4-10% of make-up water from the make-up line 44. The make-up water can be water with a lower purity than pure water, such as tap water or water used for the equipment. The wastewater discharged from the wastewater desalination plant 38 (for example, RO concentrated water) is sent out of the system through the wastewater discharge line 45.

[0031] Figure 2 is a schematic diagram showing another example of a purification system equipped with a water treatment device according to this embodiment. In the purification system 5 shown in Figure 2, components similar to those in the purification system 1 shown in Figure 1 are denoted by the same reference numerals, and their descriptions are omitted. In the purification system 5 shown in Figure 2, the exhaust gas purification device 12 includes a first ancillary equipment 46.

[0032] The first ancillary equipment 46 is equipment installed around the exhaust gas treatment equipment 14 to use the second desalination treated water, which has been desalinized by the desalination equipment 30, for a purpose other than scrubber water. The area around the exhaust gas treatment equipment 14 means an area within the same building or on the same floor as the exhaust gas treatment equipment 14, or an area that is unitized with the exhaust gas treatment equipment 14. Examples of the first ancillary equipment 46 include a chemical solution manufacturing device that produces a chemical solution for cleaning the inside of the exhaust gas treatment equipment 14. The second desalination treated water obtained from the desalination equipment 30 is supplied to the first ancillary equipment 46 through the treated water line 34 (treated water supply process). If the first ancillary equipment 46 includes a chemical solution manufacturing device, the supplied treated water and chemicals are mixed in the chemical solution manufacturing device to produce a chemical solution. The chemical solution is used, for example, to clean the inside of the exhaust gas treatment equipment 14. Specifically, examples include solutions containing inorganic alkaline agents such as sodium hydroxide, potassium hydroxide, ammonia, and sodium metasilicate, and organic alkaline agents such as choline and TMAH. The chemical solution produced in the chemical solution manufacturing device is sprayed onto the inner walls of the exhaust gas treatment equipment 14 through a chemical solution line 47 connecting the chemical solution manufacturing device and the exhaust gas treatment equipment 14, dissolving or dispersing solid matter adhering to the inner walls, thereby cleaning the inside of the exhaust gas treatment equipment 14. The second desalination water is preferably pure water with an conductivity of approximately 10 μS / cm or less, preferably 1 μS / cm or less. If clarified water is supplied, the removal of solid matter adhering to the inner walls of the exhaust gas treatment equipment 14 may be insufficient.

[0033] Figure 3 is a schematic diagram showing another example of a purification system equipped with a water treatment device according to this embodiment. In the purification system 6 shown in Figure 3, the same reference numerals are used for components similar to those in the purification system 1 shown in Figure 1, and their descriptions are omitted. In the purification system 6 shown in Figure 3, the exhaust gas purification device 12 includes a second ancillary equipment 50. The second ancillary equipment 50 is installed around the exhaust gas treatment equipment 14 and is not particularly limited as long as it is equipment for treating exhaust gas, but examples include a water electrolysis hydrogen generator that generates hydrogen gas by electrolyzing water, and a cleaning solution manufacturing device that produces cleaning solution. The area around the exhaust gas treatment equipment 14 means the area within the same building or on the same floor as the exhaust gas treatment equipment 14.

[0034] The second desalination treatment water obtained from the desalination equipment 30 is supplied to the second ancillary equipment 50 through the treated water line 35 (treated water line B) connecting the desalination equipment 30 and the second ancillary equipment 50 (treated water supply process). If the second ancillary equipment 50 includes a water electrolysis hydrogen generator, the treated water supplied to the water electrolysis hydrogen generator is electrolyzed to produce hydrogen gas. Specifically, the water electrolysis hydrogen generator is equipped with an electrolytic cell having an anode and a cathode, and the treated water supplied to the electrolytic cell is electrolyzed, producing hydrogen gas from the cathode side (oxygen gas from the anode side). The produced hydrogen gas is supplied to the gas-liquid contact section 14a of the exhaust gas treatment equipment 14 through a hydrogen gas line 52 connecting the water electrolysis hydrogen generator and the gas-liquid contact section 14a of the exhaust gas treatment equipment 14 (hydrogen gas supply process). Within the gas-liquid contact section 14a, harmful components such as PFCs and NOx in the exhaust gas are reduced and decomposed by the hydrogen gas. By using scrubber water and hydrogen gas in combination, the exhaust gas treatment efficiency can be increased. Alternatively, a hydrogen gas line may be installed connecting the water electrolysis hydrogen generator and the gas discharge line 20, and the hydrogen gas generated by the water electrolysis hydrogen generator may be supplied from this hydrogen gas line to the gas treated by the exhaust gas treatment equipment 14 (treatment gas) (hydrogen gas supply process). This reduces and decomposes any harmful components remaining in the treatment gas. The water supplied to the electrolysis hydrogen generator is preferably pure water with an conductivity of approximately 10 μS / cm or less, preferably 1 μS / cm or less. Supplying water that is not clear can lead to various problems such as decreased electrolysis efficiency, decreased purity of the generated hydrogen, and scale formation causing equipment failure.

[0035] If the second ancillary equipment 50 includes a cleaning solution manufacturing device, the second desalination treated water supplied is used in the cleaning solution manufacturing device to produce a cleaning solution. The cleaning solution is, for example, an alkaline aqueous solution such as hydrogen peroxide or sodium hydroxide. The manufactured cleaning solution is used, for example, as scrubber water. That is, the cleaning solution produced by the cleaning solution manufacturing device is sprayed into the gas-liquid contact section 14a and comes into gas-liquid contact with the exhaust gas passing through the gas-liquid contact section 14a, reacting with harmful components in the exhaust gas and removing them from the exhaust gas. The cleaning solution may be supplied to the desalination treated water line 18, or it may be supplied to the gas-liquid contact section 14a through line 52. By using the above cleaning solution as scrubber water, the exhaust gas treatment efficiency can be increased. Alternatively, the cleaning solution produced by the cleaning solution manufacturing device may be supplied to the gas treated by the exhaust gas treatment equipment (processed gas). This treats any harmful components remaining in the processed gas.

[0036] This embodiment makes it possible to supply highly purified water to the second ancillary equipment 50. This increases the exhaust gas treatment efficiency of the second ancillary equipment 50. The second ancillary equipment 50 preferably includes a water electrolysis hydrogen generator, from the viewpoint of efficiently generating hydrogen gas that can efficiently reduce harmful gases. The wastewater discharged from the second ancillary equipment 50 may be discharged outside the system, discharged to the exhaust gas treatment equipment 14 through the wastewater line 36, or returned to the desalination treatment water line 18 or the inlet of the desalination equipment 30.

[0037] Figure 4 is a schematic diagram showing another example of a purification system equipped with a water treatment device according to this embodiment. In the purification system 7 shown in Figure 4, the same reference numerals are used for components similar to those in the purification system 6 shown in Figure 3, and their descriptions are omitted. In the purification system 7 shown in Figure 4, one end of the drainage line 36 is connected to the drainage outlet (not shown) of the desalination equipment 30, and the other end is connected to the desalination treated water line 18. The drainage line 36 in Figure 4 functions as a return line that returns the wastewater discharged from the desalination equipment 30 to the desalination treated water line 18 (scrubber water line) through which the first desalination treated water (scrubber water) flows. By returning the wastewater discharged from the desalination equipment 30 to the desalination treated water line 18 (return process), the wastewater is mixed with the desalination treated water and supplied to the gas-liquid contact section 14a of the exhaust gas treatment equipment 14, thereby suppressing the reduction in the amount of scrubber water supplied. In Figure 4, the drainage line 36 is connected to the desalination treatment water line 18 so that the drainage is returned upstream of the desalination equipment 30. However, it may also be connected to the desalination treatment water line 18 so that the drainage is returned downstream of the desalination equipment 30.

[0038] The following describes the preferred treatment conditions for water treatment in this embodiment.

[0039] The exhaust gas treatment equipment 14 is installed in a dedicated space within a manufacturing plant, such as a semiconductor manufacturing plant. Generally, such spaces do not have supply lines for pure water or ultrapure water. Therefore, laying new supply lines to supply these to the exhaust gas treatment equipment 14 would be long and costly. In addition, the increased use of pure water and ultrapure water may necessitate the expansion of pure water and ultrapure water production facilities. To mitigate such high costs, it is preferable that the desalination equipment 30 be installed in the same building as the exhaust gas treatment equipment 14, and even more preferable that it be unitized with the exhaust gas treatment equipment 14. Here, unitization refers to the exhaust gas treatment equipment 14 and the desalination equipment 30 being integrated. Specifically, the exhaust gas treatment equipment 14 and the desalination equipment 30 are housed in a casing or fixed to a frame to form an integrated unit. When the desalination equipment 30 and the exhaust gas treatment equipment 14 are installed in the same building, it is desirable to install the desalination equipment 30 in the vicinity of the exhaust gas treatment equipment 14. It should be noted that the desalination equipment 30 may be installed in a building separate from the building where the exhaust gas treatment equipment 14 is installed, but in that case, the treated water line 34 that supplies the second desalination treated water from the desalination equipment 30 to the exhaust gas treatment equipment 14 will be longer.

[0040] One desalination unit 30 may be installed for one exhaust gas treatment unit 14, or one desalination unit 30 may be installed for multiple exhaust gas treatment units 14.

[0041] The amount of second desalination treated water supplied from the desalination equipment 30 to the exhaust gas treatment equipment 14, the first ancillary equipment 46, or the second ancillary equipment 50 depends on the scale of the equipment, but for example, since only a small amount of hydrogen gas needs to be supplied for the reduction treatment of the exhaust gas, it is sufficient to supply about 1 / 10 to 1 / 1000 of the amount of first desalination treated water supplied from the first desalination treated water tank 40 to the exhaust gas purification device 12. Therefore, the desalination equipment 30 can be compact, and as mentioned above, it is easy to install it in the same building as the exhaust gas treatment equipment 14 or to unitize it with the exhaust gas treatment equipment 14. The amount of first desalination treated water supplied from the first desalination treated water tank 40 to the exhaust gas treatment equipment 14 depends on the scale of the equipment, but for example, it is in the range of 1 to 100 L / min.

[0042] The desalination equipment 30 preferably includes an EDI device. By using an EDI device, for example, chemical injection equipment becomes unnecessary, and the desalination equipment 30 can be made more compact. The first desalination water stored in the first desalination water tank 40 from the wastewater desalination equipment 38 may contain ammonia and be alkaline (pH 9 or higher), or it may contain fluorine and be acidic (pH 5 or lower). In this case, when the desalination equipment 30 uses an RO membrane alone for treatment, it is desirable to adjust the pH of the first desalination water to the neutral range (e.g., pH 6-8) before treatment, for example, in order to increase the rejection rate of ammonia or fluorine. When treating the first desalination water that contains ammonia and is alkaline, or the first desalination water that contains fluorine and is acidic, it is preferable to use an EDI device that can remove ammonia or fluorine without adjusting the pH to the neutral range. This can reduce costs by making the pH adjustment equipment smaller or eliminating it altogether. Even if pH adjustment is not performed, it is preferable to install an RO membrane before the EDI to reduce components other than ammonia or fluorine. Alternatively, the hydrogen gas emitted from the electrode water of the EDI device may be recovered and used for exhaust gas treatment in the exhaust gas treatment facility 14.

[0043] [Note] Configuration 1: A desalination treatment water line that supplies desalination treatment water as scrubber water to an exhaust gas treatment facility that processes exhaust gases, A water supply line that branches off from the desalination water line and carries a portion of the desalination water, A desalination facility that further desalinates a portion of the desalination treated water supplied in the aforementioned water supply line, A water treatment apparatus comprising: a treated water line A that supplies treated water, desalinated by the desalination equipment, to the exhaust gas treatment equipment or a first ancillary facility installed around the exhaust gas treatment equipment as water to be used for purposes other than the scrubber water; or a treated water line B that supplies treated water to a second ancillary facility installed around the exhaust gas treatment equipment for treating the exhaust gas. Configuration 2: The water treatment apparatus according to configuration 1, wherein the electrical conductivity of the treated water desalinated by the desalination equipment is 10 μS / cm or less. Configuration 3: The water treatment apparatus according to configuration 1 or 2, characterized in that the desalination equipment includes an EDI device. Configuration 4: The water treatment apparatus according to any one of configurations 1 to 3, characterized in that the desalination equipment is installed in the same building as the exhaust gas treatment equipment. Configuration 5: The water treatment apparatus according to any one of configurations 1 to 4, characterized in that the desalination equipment is unitized with the exhaust gas treatment equipment. Configuration 6: The water treatment apparatus according to any one of configurations 1 to 5, characterized in that the first ancillary equipment is a chemical solution manufacturing apparatus. Composition 7: The second ancillary equipment includes a water electrolysis hydrogen generator that generates hydrogen gas by electrolyzing water, A water treatment apparatus according to any one of configurations 1 to 6, characterized in that it has a hydrogen gas line that supplies the hydrogen gas generated by supplying treated water, which has been desalted by the desalination equipment via the treated water line B, to the exhaust gas treated by the exhaust gas treatment equipment or the gas treated by the exhaust gas treatment equipment. Composition 8: A water treatment apparatus according to any one of configurations 1 to 7, characterized in that it has a return line for returning wastewater discharged from the desalination equipment to the scrubber water line for supplying the scrubber water to the exhaust gas treatment equipment. Composition 9: A water treatment system characterized by comprising a water treatment device described in any one of configurations 1 to 8 and the exhaust gas treatment equipment. Configuration 10: Step A involves supplying desalination-treated water as scrubber water to an exhaust gas treatment facility that processes exhaust gases, Step B involves branching off from the desalination water line and supplying a portion of the desalination water, A desalination treatment step in which a portion of the desalination treatment water supplied in step B is further desalinized by a desalination facility, A water treatment method characterized by comprising: a treated water supply step of supplying the treated water after the desalination step to the exhaust gas treatment equipment or a first ancillary equipment installed around the exhaust gas treatment equipment as water to be used for purposes other than the scrubber water, or a treated water supply step of supplying the treated water to a second ancillary equipment installed around the exhaust gas treatment equipment for treating the exhaust gas. [Explanation of Symbols]

[0044] 1,5,6,7 Purification system, 2 Water treatment system, 3 Wastewater recovery system, 10 Water treatment device, 12 Exhaust gas purification device, 14 Exhaust gas treatment equipment, 14a Gas-liquid contact section, 14b Storage section, 16 Exhaust gas inlet line, 18 Desalination treated water line, 20 Gas discharge line, 22 Wastewater discharge line, 24 Circulation line, 26 Circulation pump, 28a,28b Fluid nozzle, 30 Desalination equipment, 32 Water supply line, 34,35 Treated water line, 36 Drainage line, 38 Wastewater desalination equipment, 40 First desalination treated water tank, 42 ​​Desalination treated water line, 44 Supply line, 45 Wastewater discharge line, 46 First ancillary equipment, 47 Chemical line, 50 Second ancillary equipment, 52 Hydrogen gas line.

Claims

1. A desalination treatment water line that supplies desalination treatment water as scrubber water to an exhaust gas treatment facility that processes exhaust gases, A water supply line that branches off from the desalination water line and carries a portion of the desalination water, A desalination facility that further desalinates a portion of the desalination treated water supplied in the aforementioned water supply line, A water treatment apparatus comprising: a treated water line A that supplies treated water, desalinated by the desalination equipment, to the exhaust gas treatment equipment or a first ancillary equipment installed around the exhaust gas treatment equipment as water to be used for purposes other than the scrubber water, or a treated water line B that supplies treated water to a second ancillary equipment installed around the exhaust gas treatment equipment for treating the exhaust gas.

2. The water treatment apparatus according to claim 1, wherein the electrical conductivity of the treated water desalinated by the desalination equipment is 10 μS / cm or less.

3. The water treatment apparatus according to claim 1 or 2, characterized in that the desalination equipment includes an EDI device.

4. The water treatment apparatus according to claim 1 or 2, characterized in that the desalination equipment is installed in the same building as the exhaust gas treatment equipment.

5. The water treatment apparatus according to claim 1 or 2, characterized in that the desalination equipment is unitized with the exhaust gas treatment equipment.

6. The water treatment apparatus according to claim 1 or 2, characterized in that the first ancillary equipment is a chemical solution manufacturing apparatus.

7. The second ancillary equipment includes a water electrolysis hydrogen generator that generates hydrogen gas by electrolyzing water, The water treatment apparatus according to claim 1 or 2, characterized in that it has a hydrogen gas line that supplies the hydrogen gas generated by supplying the treated water, which has been desalted by the desalination equipment via the treated water line B to the water electrolysis hydrogen generator, to the exhaust gas or gas treated by the exhaust gas treatment equipment.

8. The water treatment apparatus according to claim 1 or 2, characterized in that it has a return line for returning the wastewater discharged from the desalination equipment to the desalination treated water line for supplying the scrubber water to the exhaust gas treatment equipment.

9. A water treatment system comprising the water treatment apparatus described in claim 1 or 2 and the exhaust gas treatment equipment.

10. Step A involves supplying desalination-treated water as scrubber water to an exhaust gas treatment facility that processes exhaust gases, Step B involves branching the desalination treatment water to obtain a portion of the desalination treatment water, A desalination treatment step in which a portion of the desalination treatment water obtained in step B is further desalinized using a desalination facility, A water treatment method characterized by comprising: a treated water supply step of supplying the treated water after the desalination step to the exhaust gas treatment equipment or a first ancillary equipment installed around the exhaust gas treatment equipment as water to be used for purposes other than the scrubber water, or a treated water supply step of supplying the treated water to a second ancillary equipment installed around the exhaust gas treatment equipment for treating the exhaust gas.

Images