Water quality measuring device and water treatment system

Abstract

The present invention provides a water quality measuring device that can operate a concentration device in a stable state so that the concentration ratio remains constant, and can accurately measure the water quality of treated water. [Solution] The water quality measuring device 10 includes a concentration device 2 to which treated water produced by the water treatment device 1 is supplied via a first flow path and which concentrates specific components contained in the treated water to produce concentrated water; a measuring instrument 3 to which the concentrated water produced by the concentration device 2 is supplied via a second flow path and which measures the concentration of specific components contained in the concentrated water; and a stabilization unit 6 provided in at least one of the first and second flow paths. The stabilization unit 6 is equipped with a mechanism to suppress the propagation of pressure fluctuations and / or flow rate fluctuations in the flow path located on the opposite side of the flow path from the concentration device 2 to the concentration device 2.

Description

Technical Field

[0001] The present invention relates to a water quality measurement device and a water treatment system.

Background Art

[0002] In the manufacturing processes of semiconductor devices and liquid crystal devices, pure water (including ultrapure water) from which organic substances, ion components, fine particles, bacteria and the like are highly removed is used as cleaning water. In order to produce pure water used as such cleaning water, it is required that the water quality of the pure water is always maintained at a stable high purity. In order to meet this requirement, in the pure water production process, it is preferable to manage the operation state while checking the water quality of the pure water using a water quality meter.

[0003] In general, the lower limit of the concentration that can be detected by a general-purpose measuring instrument for measuring water quality is high. Therefore, there is a limit to directly measuring the water quality of treated water at the pure water level produced by a water treatment apparatus using a general-purpose measuring instrument. Accordingly, the treated water produced by the water treatment apparatus is concentrated by a concentrator, the concentration of a specific component contained in the concentrated water is measured by a measuring instrument, and the water quality of the treated water is calculated based on the measured value and the concentration ratio of the concentrator. A water quality measurement device has been proposed. As an example of such a water quality measurement device, Patent Document 1 describes an in-water ion monitor including an electrolytic analysis device (concentrator) that concentrates ions in water, and an electrical conductivity meter (measuring instrument) that measures the electrical conductivity of the ion-concentrated water concentrated by the electrolytic analysis device. As the concentrator, a reverse osmosis (RO) membrane separation device or a regenerative ion exchange resin device can also be used.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, the water quality measuring device described above has the following problems. To accurately calculate the water quality of treated water based on the measurements from measuring instruments and the concentration ratio of the concentration device, the concentration device must be operated stably so that the concentration ratio remains constant. However, depending on the process of operating the measuring instruments and water treatment equipment, the pressure and / or flow rate of concentrated water discharged from the concentration device or treated water supplied to the concentration device may fluctuate, resulting in fluctuations in the concentration ratio and preventing the concentration device from operating stably. In this case, the water quality will be calculated using a concentration ratio different from the original concentration ratio, making it impossible to accurately calculate the water quality of the treated water produced by the water treatment equipment.

[0006] The object of the present invention is to provide a water quality measuring device and a water treatment system that can operate a concentration device in a stable state so that the concentration ratio remains constant, and can accurately measure the water quality of treated water. [Means for solving the problem]

[0007] To achieve the above objective, according to one aspect of the present invention, a water quality measuring device is provided, comprising: a concentration device to which treated water produced by a water treatment device is supplied through a first channel and which concentrates specific components contained in the treated water to produce concentrated water; a measuring instrument to which the concentrated water produced by the concentration device is supplied through a second channel and which measures the concentration of the specific components contained in the concentrated water; and a stabilization unit provided in at least one of the first channel and the second channel, wherein the stabilization unit has a mechanism to suppress the propagation of pressure fluctuations and / or flow rate fluctuations occurring in the channel on the opposite side of the channel from the concentration device to the concentration device side.

[0008] According to another aspect of the present invention, a water treatment system is provided comprising: a water treatment apparatus that treats water to be treated to produce treated water; a concentration apparatus to which at least a portion of the treated water produced by the water treatment apparatus is supplied via a first flow path and to which specific components contained in the treated water are concentrated to produce concentrated water; a measuring instrument to which the concentrated water produced by the concentration apparatus is supplied via a second flow path and to which the concentration of the specific components contained in the concentrated water is measured; and a stabilization unit provided in at least one of the first flow path and the second flow path, wherein the stabilization unit comprises a mechanism to suppress the propagation of pressure fluctuations and / or flow rate fluctuations occurring in the flow path located on the opposite side of the flow path from the concentration apparatus to the concentration apparatus side. [Effects of the Invention]

[0009] According to the present invention, the concentration device can be operated stably so that the concentration ratio remains constant, and the water quality of the treated water can be accurately measured. [Brief explanation of the drawing]

[0010] [Figure 1] This is a block diagram showing the configuration of a water treatment system equipped with a water quality measuring device, which is a first embodiment of the present invention. [Figure 2] This is a schematic diagram showing one example of a concentration device configuration. [Figure 3] This is a schematic diagram showing another example of the configuration of the concentration device. [Figure 4] This is a schematic diagram showing yet another example of the configuration of the concentration device. [Figure 5] This is a schematic diagram showing yet another example of the configuration of the concentration device. [Figure 6] This is a block diagram showing an example configuration of a measuring instrument. [Figure 7] This figure shows an example of pressure fluctuations caused by measuring instruments. [Figure 8] This figure shows the pressure changes that occur in the stabilization unit. [Figure 9] This is a block diagram showing one example configuration of a stabilization unit. [Figure 10] FIG. 2 is a block diagram showing the configuration of a water treatment system provided with a water quality measurement apparatus that is the second embodiment of the present invention. [Figure 11] FIG. is a diagram showing pressure changes occurring in a stabilization unit. [Mode for Carrying Out the Invention]

[0011] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. However, the components described in the embodiments are merely examples, and are not intended to limit the scope of the present invention thereto.

[0012] (First Embodiment) FIG. 1 is a block diagram showing the configuration of a water treatment system provided with a water quality measurement apparatus that is the first embodiment of the present invention. In FIG. 1, solid line arrows indicate flow paths (or pipes), and broken line arrows indicate signals (or signal lines).

[0013] Referring to FIG. 1, a water treatment system 100 includes a water treatment apparatus 1, a water quality measurement apparatus 10, and a monitoring unit 11. The water treatment apparatus 1 treats raw water 1a to produce treated water 1b. The treated water 1b is, for example, pure water (or ultrapure water), and has a specific resistance value of, for example, 0.10 MΩ·cm or more (10 μS / cm or less in terms of conductivity). The treated water 1b produced by the water treatment apparatus 1 is branched into two streams, one of which is supplied as treated water 1c to a use point or a downstream treatment apparatus, and the other of which is supplied as treated water 1d to the water quality measurement apparatus 10. The water treatment apparatus 1 includes, for example, at least one of a reverse osmosis (RO) membrane separation apparatus, a regenerative ion exchange resin apparatus, a non-regenerative ion exchange resin apparatus, and an electrically regenerative deionized water production apparatus (EDI apparatus). The water treatment apparatus 1 may further include other apparatuses for water treatment.

[0014] Water quality measurement device 10 includes a concentration device 2, a measurement meter 3, treated water concentration calculation means 4, a water supply pump 5, and a stabilization unit 6. The concentration device 2 is configured such that treated water 1d, which is a part of the treated water 1b produced by the water treatment device 1, flows therethrough. The flow path for supplying the treated water 1d to the concentration device 2 can be referred to as the first flow path. The water supply pump 5 is provided in the first flow path, and pressurizes the treated water 1d from the water treatment device 1 to supply the water to the concentration device 2. It is also assumed that some of these constituent elements may be omitted. For example, cases where the water supply pump 5 is not provided, or cases where the treated water concentration calculation means 4 is not provided are assumed.

[0015] The concentration device 2 concentrates a specific component (component to be concentrated) contained in the treated water 1d. The concentration device 2 supplies a signal S1 indicating the concentration factor to the treated water concentration calculation means 4. The concentration device 2 is, for example, a desalination device that produces at least concentrated water 2a and desalinated treated water 2b. The removal rate (desalination rate) of the specific component is 90% or more, preferably 95% or more, and more preferably 99% or more. The concentration factor of the concentrated water 2a relative to the treated water 1d is 3 times or more, preferably 10 times or more, and more preferably 20 times or more. In the present embodiment, the removal rate (desalination rate) is set to 90% or more, and the concentration factor is set in the range of 3 to 20 times. The concentrated water 2a is supplied to the stabilization unit 6. The desalinated treated water 2b merges with the treated water 1c and is supplied to a use point or the like. It is also possible to supply the entire treated water 1b produced by the water treatment device 1 to the concentration device 2 as the treated water 1d.

[0016] Here, the configuration of the concentration device 2 and its concentration factor will be specifically described. Figure 2 is a schematic diagram showing one configuration example of the concentration device 2. The concentration device 2 shown in Figure 2 is an EDI device, which has a desalination chamber 20, a concentration chamber 21, and an electrode chamber 22. The treated water 1d from the water treatment device 1 is pressurized by the water supply pump 5 and then supplied to the desalination chamber 20 as feed water. The flow rate of the feed water supplied to the desalination chamber 20 is set to 150 L / h. The desalination chamber 20 discharges desalinated treated water. The flow rate of the desalinated treated water discharged from the desalination chamber 20 is set to 150 L / h.

[0017] A portion of the desalination treatment water discharged from the desalination chamber 20 is supplied to the concentration chamber 21 and the electrode chamber 22. The flow rate of the remaining desalination treatment water, after deducting the amount supplied to the concentration chamber 21 and the electrode chamber 22, is set to 125 L / h. This remaining desalination treatment water corresponds to the desalination treatment water 2b shown in Figure 1. The concentration chamber 21 discharges concentrated water 2a. The flow rate of concentrated water 2a discharged from the concentration chamber 21 is 15 L / h. The electrode chamber 22 discharges electrode water. The flow rate of electrode water discharged from the electrode chamber 22 is 10 L / h.

[0018] The concentration ratio of the concentration device 2 can be calculated as follows, based on the flow rate of the remaining desalination treatment water 2b, the flow rate of the concentrated water 2a, and the flow rate of the electrode water.

number

[0019] Figure 3 is a schematic diagram showing another configuration example of the concentration apparatus 2. This example of concentration apparatus 2, like the concentration apparatus 2 shown in Figure 2, consists of an EDI device. This example of concentration apparatus 2 is identical to the concentration apparatus 2 shown in Figure 2, except for differences in the water flow paths of the concentration chamber 21 and the electrode chamber 22. The same reference numerals are used for the same components, and their detailed explanations are omitted.

[0020] In the concentration apparatus 2 of this example, a portion of the supply water supplied from the water pump 5 to the desalination chamber 20 is branched off and supplied to the concentration chamber 21 and the electrode chamber 22. The water flow rate of the water pump 5 is set to 150 L / h. The flow rate of the desalination treated water discharged from the desalination chamber 20 is set to 125 L / h. The flow rate of the concentrated water 2a discharged from the concentration chamber 21 is set to 15 L / h. The flow rate of the electrode water discharged from the electrode chamber 22 is set to 10 L / h.

[0021] The concentration ratio of the concentration device 2 in this example can also be calculated based on the formula described above, and is 10 times. By dividing the measured value of the measuring instrument 3 by this concentration ratio, it is possible to calculate the concentration (converted value) of the specific component in the treated water 1b. If the concentration chamber 21 also serves as the electrode chamber 22, the flow rate of the electrode water is omitted when calculating the concentration ratio.

[0022] Figure 4 is a schematic diagram showing yet another configuration example of the concentration device 2. The concentration device 2 shown in Figure 4 consists of an RO membrane separator 70. Treated water 1d from the water treatment device 1 is pressurized by the water supply pump 5 and then supplied to the RO membrane separator 70 as feedwater. The flow rate of the feedwater supplied to the RO membrane separator 70 is 1.24 m³. 3 The flow rate of concentrated water 2a discharged from the RO membrane separator 70 is 0.12 m³ / h. 3 Let's assume the flow rate of the desalination treatment water 2b discharged from the RO membrane separator 70 is 1.12 m³ / h. 3 Set to / h

[0023] The concentration ratio of the RO membrane separation device 70 can be calculated as follows.

number

[0024] Furthermore, in the concentration device 2 described above, a portion of the concentrated water 2a may be branched off and returned to the upstream stage of the water supply pump 5 as concentrated circulating water, and the remaining concentrated water may be supplied to the stabilization unit 6. With this configuration, the concentration ratio of the concentration device 2 can be increased. Figure 5 shows an example configuration of a concentration device 2 equipped with a flow path for concentrated circulating water. This concentration device 2 is the same as the one shown in Figure 4, except that it is equipped with a flow path for concentrated circulating water. Treated water 1d and concentrated circulating water 2c are supplied to the RO membrane separator 70 as feedwater. The flow rate of the feedwater supplied to the RO membrane separator 70 is set to 145 L / h, which is the sum of the flow rate of treated water 1d (115 L / h) and the flow rate of concentrated circulating water 2c (30 L / h). The RO membrane separator 70 discharges concentrated water 2a and desalination treated water (permeate) 2b. The flow rate of desalination treated water 2b discharged from the RO membrane separator 70 is set to 103 L / h. Of the concentrated water 2a discharged from the RO membrane separator 70 before branching, concentrated circulating water 2c (flow rate 30 L / h) is returned to the upstream of the supply pump 5, and the remaining concentrated water 2d (flow rate 12 L / h) is sent to the measuring instrument 3.

[0025] The concentration ratio of the RO membrane separation device 70 described above can be calculated using the following formula.

number

[0026] Refer to Figure 1 again. The concentrated water produced by the concentration device 2 is supplied to the measuring instrument 3 via a second flow path, and a stabilization unit 6 is provided in the second flow path. Here, the concentrated water 2a produced by the concentration device 2 is supplied to the stabilization unit 6, and the concentrated water 2c discharged from the stabilization unit 6 is supplied to the measuring instrument 3. In this case, the second flow path consists of a flow path for concentrated water 2a and a flow path for concentrated water 2c. The stabilization unit 6 is equipped with a mechanism to suppress the propagation of pressure fluctuations and / or flow rate fluctuations occurring in the flow path located on the opposite side of the flow path from the concentration device 2 (the flow path for concentrated water 2c) to the concentration device 2. The detailed configuration of the stabilization unit 6 will be described later.

[0027] The measuring instrument 3 measures the concentration of specific components contained in the concentrated water 2c supplied from the stabilization unit 6. The measuring instrument 3 supplies a signal S2 indicating the measured value to the treated water concentration calculation means 4. The measuring instrument 3 is an instrument that measures the concentration of one of the following components, for example: silica, boron, metal ions (sodium, aluminum, calcium, magnesium, etc.), carbonic acid, IC (inorganic carbon), and TOC (total organic carbon). Note that these instruments are just examples, and instruments that measure the concentration of other components may be used. The concentrated water that has passed through the measuring instrument 3 is basically discarded, but from the viewpoint of utilization efficiency, it may be returned to the upstream or downstream stage of the water treatment device 1, or used in other systems.

[0028] The treated water concentration calculation means 4 calculates the concentration value (converted value) of a specific component in the treated water 1b by dividing the measurement value from the measuring instrument 3 by the concentration ratio of the concentration device 2. The treated water concentration calculation means 4 supplies a signal S3 indicating the concentration value (converted value) to the monitoring unit 11. The concentration ratio may be a value set in advance, or it may be a value that is constantly calculated from the values ​​of each flow meter (not shown) installed in the concentration device 2.

[0029] The monitoring unit 11 monitors the water quality of the treated water 1b based on the signal S3 (concentration value (converted value)) supplied from the treated water concentration calculation means 4. The monitoring unit 11 has an adjustment means 41 and an alarm means 42. The adjustment means 41 adjusts the operation of the water treatment device 1 for specific components based on the concentration value (converted value) of the specific component in the treated water 1b. For example, the adjustment means 41 adjusts the operation of the water treatment device 1 when the concentration value (converted value) of the specific component in the treated water 1b exceeds a threshold or when the concentration change of the specific component shows a predetermined trend. The predetermined trend includes, for example, a trend indicating a decrease in treatment performance for the specific component. The adjustment means 41 is configured to be able to adjust at least one of the following: flow rate adjustment, chemical regeneration, ion exchange resin replacement, current adjustment, water temperature adjustment, series switching, and pH adjustment. Note that these adjustments may also be performed by the administrator. Alternatively, the monitoring unit 11 may consist only of the alarm means 42 and lack the adjustment means 41.

[0030] Flow rate adjustment involves, for example, adjusting the flow rate of the water supplied to the water treatment device 1 (water to be treated 1a). Chemical regeneration involves, for example, regenerating the ion exchange resin in a regenerative ion exchange resin device using chemicals. Ion exchange resin replacement involves, for example, replacing the ion exchange resin in a device using ion exchange resin (ion exchange device). Current adjustment involves, for example, adjusting the current applied between the anode and cathode of an EDI device. Water temperature adjustment involves, for example, adjusting the water temperature of the water supplied to the EDI device or RO membrane separation device. pH adjustment involves adding a pH adjusting agent to the water to be treated 1a. pH adjusting agents include alkaline agents such as calcium hydroxide and sodium hydroxide, and acidic agents such as sulfuric acid and hydrochloric acid. Series switching involves, for example, having multiple series connected in parallel to each other to treat the water to be treated, and switching between these series. For example, the multiple series include a backup series and a main series, and the backup series is switched from the main series in response to the detection of ion leaks. Furthermore, when operating multiple regenerative resin processing units in series, it is possible to regenerate the unit that is being shut down during a series switchover in preparation for the next switchover.

[0031] The alarm means 42 outputs an alarm based on the concentration value (converted value) of a specific component in the treated water 1b. For example, the alarm means 42 outputs an alarm when the concentration value (converted value) of a specific component in the treated water 1b exceeds a threshold, or when the change in the concentration of a specific component shows the predetermined trend described above. The alarm means 42 may include a display device that displays a warning message, or a speaker that outputs a warning sound. In this case, the administrator can perform the necessary work for performance recovery processing in response to the alarm (message or warning sound) from the alarm means 42.

[0032] In the water quality measuring device 10 described above, depending on the process of operating the measuring instrument 3, the pressure and / or flow rate of the concentrated water discharged from the concentrator 2 may fluctuate, resulting in fluctuations in the concentration ratio and potentially preventing the concentrator 2 from operating stably. The fluctuations in the pressure and / or flow rate of concentrated water due to pressure fluctuations by the measuring instrument 3 are described below.

[0033] Figure 6 is a schematic block diagram showing one example configuration of the measuring instrument 3. The measuring instrument 3 shown in Figure 6 has at least a reaction unit 31 and a detection unit 32, and valves V1 to V4. Concentrated water 2c from the stabilization unit 6 is supplied to the flow path 30a. Flow path 30a is branched into two flow paths 30b and 30c. Flow path 30b is a flow path for discharging concentrated water supplied from flow path 30a to the outside of the instrument when in standby mode, and is provided with valve V1. The discharge of concentrated water can be controlled by opening and closing valve V1.

[0034] The flow path 30c is connected to the reaction section 31 via valve V2. The reaction section 31 is a so-called reaction cell into which reagents necessary for measuring absorbance are added and reacted with a specific component (substance to be measured). During the absorbance measurement process, the reaction section 31 discharges the concentrated water containing the reagents into the flow path 30d. In addition, during the rinsing process (outside the measurement period), the reaction section 31 rinses the cell using a rinsing solution and discharges the wastewater into the flow path 30e. Valve V3 is provided in the flow path 30e. In this embodiment, concentrated water is used as the rinsing solution, but it is not limited to this. Clear water such as pure water may be used as the rinsing solution.

[0035] The flow path 30d is connected to the detection unit 32 via the valve V4. In the absorbance measurement process, the detection unit 32 irradiates the concentrated water supplied from the reaction unit 31 with light of a specific wavelength to measure its absorbance. In the rinsing process (outside the measurement period), the detection unit 32 rinses the cells using a rinsing solution. The concentrated water used for absorbance measurement and the waste liquid generated from rinsing the cells are discharged from the detection unit 32 into the flow path 30f. In this embodiment, concentrated water is used as the rinsing solution, but it is not limited to this. Clear water such as pure water may be used as the rinsing solution.

[0036] In the measuring instrument 3 shown in Figure 6, a standby process, a rinsing process for the reaction section 31, a rinsing process for the detection section 32, and a measurement process are performed. In the standby process, valve V1 is opened, and all remaining valves V2 to V4 are closed. As a result, the concentrated water 2c from the stabilization unit 6 flows through channels 30a and 30b and is discharged from the measuring instrument 3.

[0037] In the rinsing process of the reaction section 31, valves V1 and V4 are closed, and valves V2 and V3 are opened. As a result, concentrated water 2c from the stabilization unit 6 flows through channels 30a and 30c and is supplied to the reaction section 31, and then flows through channel 30e and is discharged from the measuring instrument 3. The cells of the reaction section 31 are washed using the concentrated water 2c.

[0038] In the rinsing process of the detection unit 32, valves V1 and V3 are closed, and valves V2 and V4 are open. As a result, concentrated water 2c from the stabilization unit 6 flows through channels 30a and 30c and is supplied to the reaction unit 31. The concentrated water 2c that has passed through the reaction unit 31 flows through channel 30d and is supplied to the detection unit 32, and then flows through channel 30f and is discharged from the measuring instrument 3. The cells of the detection unit 32 are washed using the concentrated water 2c. Note that this rinsing process of the detection unit 32 and the rinsing process of the reaction unit 31 described above can be processed as a single rinsing process.

[0039] In the measurement process, valves V1, V3, and V4 are closed, and valve V2 is open, to store a predetermined amount of concentrated water in the reaction section 31. Then, valve V2 is closed and valve V1 is opened. After adding a reagent to the concentrated water stored in the reaction section 31 and allowing it to react, valve V4 is opened, and the reacted concentrated water is sent to the detection section 32, where the concentration is measured using a measuring detector such as an absorbance detector. After the measurement is completed, the rinsing process described above is performed to rinse the inside.

[0040] Pressure fluctuations occur during the standby, rinsing, and measurement processes described above. Figure 7 shows an example of the pressure fluctuations caused by these processes. As shown in Figure 7, the pressure during the rinsing process is higher than the pressure during the standby and measurement processes. Furthermore, the pressure during the rinsing process fluctuates in a rectangular wave pattern.

[0041] In the water quality measuring device 10 shown in Figure 1, pressure fluctuations in each step of the measuring instrument 3, as described above, propagate to the concentrator 2 via the flow path. Therefore, if the stabilization unit 6 is not present, the following problems will occur.

[0042] Pressure fluctuations in each step of the measuring instrument 3 cause fluctuations in the pressure and / or flow rate of the concentrated water (2a, 2c) supplied from the concentrator 2 to the measuring instrument 3, resulting in fluctuations in the concentration ratio of the concentrator 2. In this case, the treated water concentration calculation means 4 calculates the water quality using a concentration ratio different from the original concentration ratio, making it difficult to accurately calculate the water quality of the treated water 1b produced by the water treatment device 1.

[0043] For example, if a concentration ratio is set in advance (let's call the set value of the concentration ratio "A"), the concentration device 2 supplies a signal S1 indicating the set value of the concentration ratio "A" to the treated water concentration calculation means 4. The treated water concentration calculation means 4 converts the measured value of the measuring instrument 3 into a concentration value of a specific component in the treated water 1b by dividing it by the set value of the concentration ratio "A". However, even if the concentration ratio deviates from the set value A due to pressure fluctuations in the measuring instrument 3, the concentration device 2 supplies a signal S1 indicating the set value "A" to the treated water concentration calculation means 4. As a result, the treated water concentration calculation means 4 calculates the water quality using a set value "A" that is different from the original concentration ratio (the value after the fluctuation).

[0044] In addition, the concentration device 2 may constantly calculate the concentration ratio from the values ​​of each flow meter and supply a signal S1 indicating the calculated value to the treated water concentration calculation means 4. In this case, if the concentration ratio changes due to pressure fluctuations in the measuring instrument 3, the concentration device 2 can supply a signal S1 indicating the calculated value of the concentration ratio after the change to the treated water concentration calculation means 4. However, when the pressure and / or flow rate of the concentrated water (2a, 2c) changes due to pressure fluctuations in the measuring instrument 3, the water quality is not stable immediately after the change, and it takes time for the water quality to stabilize from the time of the change. The stability problem (delay) is particularly pronounced in concentration devices 2 that apply an EDI device or concentration devices 2 in which a flow path for concentrated circulating water is installed in an RO membrane device. Due to this stability problem (delay), when the pressure and / or flow rate of the concentrated water (2a, 2c) supplied from the concentration device 2 to the measuring instrument 3 changes due to pressure fluctuations in the measuring instrument 3, the concentration ratio is calculated while the water quality is unstable. As a result, the treated water concentration calculation means 4 calculates the water quality using a calculated value different from the original concentration ratio (concentration ratio after variation).

[0045] In the water quality measuring device 10 of this embodiment, the stabilization unit 6 suppresses the propagation of pressure and / or flow rate fluctuations generated by the measuring instrument 3 to the concentrating device 2. Figure 8 shows the change in pressure A in the flow path of concentrated water 2a supplied to the stabilization unit 6 and the change in pressure B in the flow path of concentrated water 2c supplied from the stabilization unit 6 to the measuring instrument 3. As shown in Figure 8, the pressure B in the flow path of concentrated water 2c is higher than the pressure A in the flow path of concentrated water 2a. Also, the fluctuation in pressure A in the flow path of concentrated water 2a is smaller than the fluctuation in pressure B in the flow path of concentrated water 2c. In other words, the fluctuation in flow rate in the flow path of concentrated water 2a is smaller than the fluctuation in flow rate in the flow path of concentrated water 2c. Note that in the example in Figure 8, the pressure A in the flow path of concentrated water 2a is assumed to be approximately constant.

[0046] The stabilization unit 6 prevents fluctuations in the pressure and / or flow rate of the concentrated water 2c channel from propagating to the concentrator 2, thereby enabling the concentrator 2 to operate stably so that the concentration ratio remains constant. Therefore, the water quality of the treated water 1b can be accurately measured.

[0047] Next, we will specifically describe the configuration of the stabilization unit 6. Figure 9 is a block diagram showing one example configuration of the stabilization unit 6. As shown in Figure 9, the stabilization unit 6 has a storage unit 60 configured to store concentrated water 2a from the concentration device 2 and supply the stored water as concentrated water 2c to the measuring instrument 3. The storage unit 60 consists of a tank 61 for storing concentrated water 2a and a water supply pump 62 for pressurizing the water stored in the tank 61 and sending it to the measuring instrument 3.

[0048] According to the storage unit 60 shown in Figure 9, by providing a tank 61 between the flow path of concentrated water 2a and the flow path of concentrated water 2c, it is possible to suppress the propagation of pressure and / or flow rate fluctuations in the flow path of concentrated water 2c to the concentrating device 2. In the example shown in Figure 9, the storage unit 60 consists of a tank 61 and a water supply pump 62, but it is not limited to this. The storage unit 60 can have any configuration as long as it can store concentrated water 2a from the concentrating device 2 and supply the stored water to the measuring instrument 3. For example, a structure that uses gravity to supply concentrated water from the tank 61 to the measuring instrument 3 may be applied. In this case, a valve may be used to control the flow rate and on / off of the concentrated water. The water supply pump 62 may also be provided inside the measuring instrument 3. In this case, a measuring instrument equipped with a pump function may be used as the measuring instrument 3.

[0049] Furthermore, the stabilization unit 6 may consist of a surge tank or collector tank to suppress fluctuations in water pressure, or it may consist of a flow controller (mass flow controller) that stabilizes the flow rate and pressure while monitoring fluctuations in pressure and flow rate, as well as a constant flow valve or constant pressure valve. These may be electronically controlled or have a structure designed to maintain a constant flow rate (or pressure). A constant flow valve or constant pressure valve can maintain a constant flow rate or pressure of concentrated water flowing through the second flow path. For example, a constant flow valve may have an orifice or pilot valve in its internal structure and maintain a constant flow rate by adjusting the opening and closing of the valve using the pressure difference caused by flow rate fluctuations.

[0050] The water quality measuring device 10 of this embodiment described above is just one example, and its configuration can be changed as appropriate. For example, the number of measuring instruments 3 connected to the stabilization unit 6 may be two or more. In this case, concentrated water 2c from the stabilization unit 6 is supplied to each measuring instrument 3. It is assumed that the influence of pressure fluctuations in two or more measuring instruments 3 will be greater than the influence of pressure fluctuations in one measuring instrument 3. The stabilization unit 6 can suppress the propagation of pressure and / or flow rate fluctuations in the flow path of concentrated water 2c due to pressure fluctuations in two or more measuring instruments 3 to the concentrating device 2. Therefore, the concentrating device 2 can be operated in a stable state so that the concentration ratio remains constant, and the water quality of the treated water 1b can be accurately measured.

[0051] (Second embodiment) Figure 10 is a block diagram showing the configuration of a water treatment system equipped with a water quality measuring device, which is a second embodiment of the present invention. The water quality measuring device 10A of this embodiment has the same configuration as the water quality measuring device 10 of the first embodiment, except that the water supply pump 5 is removed and a stabilization unit 6 is provided in the flow path of the treated water 1d. The same reference numerals are used for the same components, and their detailed descriptions are omitted.

[0052] The water treatment system 100 shown in Figure 10 comprises two water treatment devices 1A and 1B. Both water treatment devices 1A and 1B are the same as the water treatment device 1 shown in Figure 1, and they treat the water to be treated 1a to produce treated water 1b. At least a portion of the treated water 1b produced by water treatment devices 1A and 1B is supplied to the water quality measuring device 10A as treated water 1d.

[0053] In the water quality measuring device 10A, the configuration of the stabilization unit 6 is as described in the first embodiment. The stabilization unit 6 is installed in the first flow path for supplying treated water 1d from the water treatment devices 1A and 1B to the concentration device 2. Treated water 1d from the water treatment devices 1A and 1B is supplied to the stabilization unit 6, and treated water 1e discharged from the stabilization unit 6 is supplied to the concentration device 2. In this case, the first flow path consists of a flow path for treated water 1d and a flow path for treated water 1e. The stabilization unit 6 is equipped with a mechanism to suppress the propagation of pressure fluctuations and / or flow rate fluctuations occurring in the flow path located on the opposite side of the concentration device 2 from the concentration device 2 (the flow path for treated water 1d) to the concentration device 2.

[0054] If the stabilization unit 6 has, for example, a storage section 60 as shown in Figure 9, the tank 61 stores the treated water 1d from the water treatment devices 1A and 1B, and the water supply pump 62 pressurizes the water stored in the tank 61 and sends it to the concentration device 2.

[0055] The concentration device 2 concentrates specific components (components to be concentrated) contained in the treated water 1e discharged from the stabilization unit 6. The concentration device 2 supplies a signal S1 indicating the concentration ratio to the treated water concentration calculation means 4. The concentrated water 2a produced by the concentration device 2 is supplied to the measuring instrument 3. The measuring instrument 3 measures the concentration of specific components contained in the concentrated water 2a supplied from the concentration device 2. The measuring instrument 3 supplies a signal S2 indicating the measured value to the treated water concentration calculation means 4.

[0056] In the water treatment system 100 shown in Figure 10, switching between water treatment device 1A and water treatment device 1B is performed. For example, a first step of operating water treatment device 1A and putting water treatment device 1B into standby mode is performed alternately, followed by a second step of operating water treatment device 1B and putting water treatment device 1A into standby mode. In this case, pressure fluctuations occur when switching between water treatment device 1A and water treatment device 1B. These pressure fluctuations cause fluctuations in the pressure and / or flow rate of treated water 1d supplied from water treatment device 1A or water treatment device 1B. If there is no stabilization unit 6, fluctuations in the pressure and / or flow rate of treated water 1d may cause fluctuations in the concentration ratio, making it impossible to operate the concentration device 2 in a stable state.

[0057] In this embodiment of the water quality measuring device 10A, the stabilization unit 6 suppresses the propagation of pressure fluctuations that occur when switching between the water treatment device 1A and the water treatment device 1B to the concentrator 2. Figure 11 shows the change in pressure A in the flow path of treated water 1d supplied to the stabilization unit 6 and the change in pressure B in the flow path of treated water 1e supplied from the stabilization unit 6 to the concentrator 2. As shown in Figure 11, the pressure B in the flow path of treated water 1e is higher than the pressure A in the flow path of treated water 1d. Also, the fluctuation in pressure B in the flow path of treated water 1e is smaller than the fluctuation in pressure A in the flow path of treated water 1d. In other words, the fluctuation in the flow rate of the flow path of treated water 1e is smaller than the fluctuation in the flow rate of the flow path of treated water 1d. Note that in the example of Figure 11, the pressure B in the flow path of treated water 1e is assumed to be approximately constant.

[0058] The stabilization unit 6 prevents fluctuations in the pressure and / or flow rate of the treated water 1d from being transmitted to the concentrator 2, thereby enabling the concentrator 2 to operate stably so that the concentration ratio remains constant. As a result, the water quality of the treated water 1b can be accurately measured.

[0059] The water quality measuring device 10A of this embodiment described above is just one example, and its configuration can be changed as appropriate. For example, a portion of the concentrated water 2a discharged from the concentration device 2 may be branched off and returned as concentrated circulating water to the downstream or upstream stage of the stabilization unit 6, or to the inside of the stabilization unit 6, and the remaining concentrated water may be supplied to the measuring instrument 3. With this configuration, the concentration ratio of the concentration device can be made higher. Furthermore, the stabilization unit 6 may be composed of the surge tank and collector tank mentioned above, or it may be composed of the flow controller (mass flow controller) mentioned above, as well as constant flow valves and constant pressure valves. A constant flow valve or constant pressure valve can maintain a constant flow rate or pressure of the treated water flowing through the first flow path.

[0060] Furthermore, in the water treatment system 100 shown in Figure 10, the number of water treatment devices may be three or more. In this case, for example, one of the water treatment devices may be set to standby mode, and the remaining water treatment devices may be operated. The standby water treatment device is switched sequentially. Pressure fluctuations occur when switching water treatment devices. These pressure fluctuations cause fluctuations in the pressure and / or flow rate of the treated water 1d supplied from the water treatment device. The stabilization unit 6 prevents the pressure and / or flow rate fluctuations in the treated water 1d flow path from propagating to the concentrator 2, thereby enabling the concentrator 2 to operate in a stable state so that the concentration ratio remains constant. Therefore, the water quality of the treated water 1b can be accurately measured.

[0061] Furthermore, the number of water treatment devices may be limited to one. In this case, pressure fluctuations occur when switching the operating process of the water treatment device (e.g., standby, switching of water supply destination). These pressure fluctuations cause fluctuations in the pressure and / or flow rate of the treated water 1d supplied from the water treatment device. The stabilization unit 6 prevents the pressure and / or flow rate fluctuations in the treated water 1d flow path from propagating to the concentrator 2, allowing the concentrator 2 to operate stably so that the concentration ratio remains constant. Therefore, the water quality of the treated water 1b can be accurately measured.

[0062] The water quality measuring device 10 and the water quality measuring device 10A described above can be combined. For example, in the water quality measuring device 10A, a stabilization unit 6 may be provided in the flow path of concentrated water discharged from the concentration device 2. In this case, the propagation to the concentration device 2 side can be suppressed for both the pressure fluctuations that occur when switching between the water treatment devices 1A and 1B and the pressure fluctuations that occur in the measuring instrument 3. [Explanation of Symbols]

[0063] 1, 1A, 1B Water Treatment Equipment 1a Water to be treated 1b, 1c, 1d Treated water 2 Concentrator 2a, 2c concentrated water 2b Desalination treated water 3 Measuring Instruments 4. Treatment water concentration calculation means 5. Water supply pump 6. Stabilization Unit 10, 10A water quality measuring device 11 Monitoring Department 41 Adjustment means 42 Alarm means 100 Water Treatment Systems

Claims

1. A water treatment device supplies treated water produced in the water treatment device through a first channel, and a concentration device concentrates specific components contained in the treated water to produce concentrated water. The concentrated water produced by the aforementioned concentration device is supplied through a second channel, and a measuring instrument is used to measure the concentration of the specific component contained in the concentrated water. The device comprises a stabilization unit provided in at least one of the first flow path and the second flow path, The stabilization unit is a water quality measuring device that includes a mechanism to suppress the propagation of pressure fluctuations and / or flow rate fluctuations occurring in the flow path located on the opposite side of the flow path from the concentration device to the concentration device side.

2. The water quality measuring device according to claim 1, wherein the stabilization unit is provided in the second flow path, and the mechanism suppresses the propagation of pressure fluctuations and / or flow rate fluctuations generated by the measuring instrument to the concentration device side.

3. The water quality measuring device according to claim 2, wherein the fluctuation in pressure and / or flow rate of concentrated water supplied from the concentration device to the stabilization unit is smaller than the fluctuation in pressure and / or flow rate of concentrated water supplied from the stabilization unit to the measuring instrument.

4. The water quality measuring device according to claim 2, wherein the pressure of the concentrated water supplied from the stabilization unit to the measuring instrument is higher than the pressure of the concentrated water supplied from the concentration device to the stabilization unit.

5. The water quality measuring device according to claim 2, comprising a plurality of the aforementioned measuring instruments, wherein the stabilization unit supplies the concentrated water to each of the measuring instruments.

6. The water quality measuring device according to claim 2, wherein the stabilization unit has a storage section that stores the concentrated water from the concentration device and supplies the stored concentrated water to the measuring instrument.

7. The water quality measuring device according to claim 2, wherein the stabilization unit has a constant flow valve or constant pressure valve that maintains a constant flow rate or pressure of concentrated water flowing through the second flow path.

8. The water quality measuring device according to claim 1, wherein the stabilization unit is provided in the first flow path, and the mechanism suppresses the propagation of pressure fluctuations and / or flow rate fluctuations generated by the water treatment device to the concentration device side.

9. The water quality measuring device according to claim 8, wherein the fluctuations in pressure and / or flow rate of the treated water supplied from the stabilization unit to the concentration device are smaller than the fluctuations in pressure and / or flow rate of the treated water supplied from the water treatment device to the stabilization unit.

10. The water quality measuring device according to claim 8, wherein the pressure of the treated water supplied from the stabilization unit to the concentration device is higher than the pressure of the treated water supplied from the water treatment device to the stabilization unit.

11. The water quality measuring apparatus according to claim 8, wherein treated water is supplied to the stabilization unit from a plurality of water treatment devices.

12. The water quality measuring device according to claim 8, wherein the stabilization unit has a storage section that stores the treated water from the water treatment device and supplies the stored treated water to the concentration device.

13. The water quality measuring device according to claim 8, wherein the stabilization unit has a constant flow valve or constant pressure valve that maintains a constant flow rate or pressure of the treated water flowing through the first flow path.

14. A water treatment apparatus that processes water to be treated and produces treated water, At least a portion of the treated water produced by the water treatment apparatus is supplied through a first channel, and a concentration device is provided that concentrates specific components contained in the treated water to produce concentrated water. The concentrated water produced by the aforementioned concentration device is supplied through a second channel, and a measuring instrument is used to measure the concentration of the specific component contained in the concentrated water. The system comprises a stabilization unit provided in at least one of the first flow path and the second flow path, The water treatment system is characterized in that the stabilization unit comprises a mechanism that suppresses the propagation of pressure fluctuations and / or flow rate fluctuations occurring in the flow path located on the opposite side of the flow path from the concentration device to the concentration device side.

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