JP6874510B2 - Water quality measuring device - Google Patents

Description

The present invention relates to a water quality measuring device used in a water treatment system.

Conventionally, electrode-type or color-matching type water quality meters (water quality measuring devices) such as chlorine concentration meters and hardness meters that measure the quality of water flowing through water treatment systems have been used (for example, patents). (See Documents 1 and 2).

The electrode type water quality meter has an advantage that the water quality of the water flowing through the water treatment system can be continuously measured, and the water quality can be measured at low cost without requiring a reagent. However, in the electrode type water quality meter, the measured value tends to be unstable due to the dirt on the electrode and the insufficient flow rate of the sample water, and the reliability of the measured value is low.

On the other hand, the colorimetric water quality meter can measure the water quality of the water flowing through the water treatment system only intermittently, but has the advantage of high reliability of the measured values. However, since the colorimetric water quality meter uses a reagent when measuring the water quality of water, if the measurement interval of the colorimetric water quality meter is shortened, the cost required for the reagent increases and the operating cost increases.

By the way, as a technique for calibrating an electrode type water quality meter, an invention relating to a calibration method of a chlorine concentration measuring device is known (see, for example, Patent Document 3). In Patent Document 3, regarding the calibration method of the electrode type chlorine concentration measuring device, in order to accurately calibrate the chlorine concentration, it is necessary to determine the chlorine concentration of the prepared standard solution, and for that purpose, the colorimetric method is used. It is stated that it is necessary to use other analytical methods such as. Further, it is known that when the residual chlorine measured by the electrode type chlorine concentration meter is confirmed by the colorimetric method, the confirmation work by the colorimetric method is performed manually (for example, Patent Document 4). reference).

Japanese Unexamined Patent Publication No. 2014-30780 Japanese Unexamined Patent Publication No. 2013-188730 Japanese Unexamined Patent Publication No. 2004-347366 Japanese Unexamined Patent Publication No. 2016-191605

In the technique described in Patent Document 3, when the water quality is accurately measured, it is necessary to calibrate the electrode type water quality meter by using another analytical method such as a colorimetric method. As described in Patent Document 4, it is known that the calibration of the electrode type water quality meter is manually performed by the colorimetric method. Therefore, it was not realistic to calibrate the electrode type water quality meter by the colorimetric method on the water treatment system.

However, as described above, the electrode type water quality meter has an advantage that the water quality can be continuously measured at low cost, and the colorimetric water quality meter has an advantage that the measured value is highly reliable. Therefore, it is possible to obtain highly reliable measured values by taking advantage of both the electrode type water quality meter that can measure continuously at low cost and the colorimetric water quality meter that has high reliability of measured values. Moreover, a water quality measuring device capable of measuring at low cost is desired.

An object of the present invention is to provide a water quality measuring device capable of obtaining highly reliable measured values of water quality flowing through a water treatment system and continuously measuring at low cost.

The present invention is a water quality measuring device for measuring the water quality of water flowing through a water treatment system including a water treatment unit, and an electrode-type detecting means for continuously detecting the water quality of water flowing through the water treatment system. The electrode type detection based on the colorimetric detection means for intermittently detecting the water quality of the water flowing through the water treatment system and the water quality detection value detected by the colorimetric detection means at a predetermined timing. The present invention relates to a water quality measuring device including a calibration execution unit that executes an operation of automatically calibrating the means.

Further, the water quality abnormality determination unit that determines whether or not the first detection value of the water quality detected by the electrode type detection means is a water quality abnormality value, and the water quality abnormality determination unit indicate that the first detection value is a water quality abnormality value. The forced detection means for forcibly detecting the water quality of the water flowing through the water treatment system as the second detection value by the colorimetric detection means, the first detection value, and the first detection means. 2 When the difference from the detected value is greater than or equal to a predetermined value, the operation of continuously detecting the water quality by the electrode type detecting means is changed to the operation of intermittently detecting the water quality by the colorimetric detection means. It is provided with a water quality abnormality control unit that executes control to switch to the control to be executed and executes control to notify the water quality abnormality when the difference between the first detection value and the second detection value is less than a predetermined value. Is preferable.

Further, the water treatment system includes a pretreatment unit arranged on the upstream side of the water treatment unit and a pretreatment unit side abnormality detection unit for detecting a water quality abnormality in the pretreatment unit, and the water quality measuring device. Detects the water quality of the water flowing downstream of the pretreatment unit, and when the water quality abnormality of the pretreatment unit is detected by the abnormality detection unit on the pretreatment unit side, the water flowing through the water treatment system The calibration execution unit includes a forced detection means that executes an operation of forcibly detecting the water quality of the water quality by the colorimetric detection means, and the calibration execution unit forcibly detects the water quality by the colorimetric detection means in the forced detection means. It is preferable to perform an operation of automatically calibrating the electrode type detection means based on the detected value of.

Further, the water treatment system includes a post-treatment unit arranged on the downstream side of the water treatment unit and a post-treatment unit side abnormality detection unit for detecting a water quality abnormality in the post-treatment unit, and the water quality measuring device. Detects the water quality of the water flowing on the upstream side of the post-treatment unit, and when the water quality abnormality of the post-treatment unit is detected by the abnormality detection unit on the post-treatment unit side, the water flowing through the water treatment system. The calibration execution unit includes a forced detection means that executes an operation of forcibly detecting the water quality of the water quality by the colorimetric detection means, and the calibration execution unit forcibly detects the water quality by the colorimetric detection means in the forced detection means. It is preferable to perform an operation of automatically calibrating the electrode type detection means based on the detected value of.

Further, the calibration execution unit may be provided with a notification control unit that controls to notify an alarm when calibration is continuously executed a predetermined number of times on the side that lowers or raises the sensitivity of the electrode type detection means. preferable.

Further, the water treatment system is a water quality changing means for changing the water quality value of the water flowing through the water treatment system to at least two or more water quality values sandwiching a predetermined target water quality value measured by the electrode type detecting means. The calibration execution unit executes an operation of calibrating the electrode type detection means based on the water quality detection value by the colorimetric detection means in each of the two or more water quality values changed by the water quality change means. It is preferable to do so.

According to the present invention, it is possible to provide a water quality measuring device capable of obtaining highly reliable measured values and continuously measuring at low cost with respect to the water quality of water flowing through a water treatment system.

It is an overall block diagram of the water treatment system of this invention. It is a block diagram which shows the structure of the water quality measuring apparatus of this embodiment.

Hereinafter, an embodiment of the water treatment system according to the present invention will be described with reference to the drawings. FIG. 1 is an overall configuration diagram of the water treatment system 1 of the present invention. FIG. 2 is a block diagram showing the configuration of the water quality measuring device 7 of the present embodiment.

As shown in FIG. 1, the water treatment system 1 of the present embodiment includes a water source 2, a pretreatment device 3 as a pretreatment section, a posttreatment device 5 as a posttreatment section, a raw water line L1, and a pretreatment. A water line L2, a post-treatment water line L4, a chemical addition device 6 as a water quality changing means, a water quality measuring device 7, and a control unit 10 are provided. The pretreatment device 3 and the posttreatment device 5 constitute a water treatment unit. Further, the water treatment system 1 includes a first turbidity sensor Tb1, a second turbidity sensor Tb2, and a third turbidity sensor Tb3.
"Line" is a general term for lines through which fluid can flow, such as channels, paths, and pipelines. The illustration of the electrical connection line between the control unit 10 and the device to be controlled is omitted.

The raw water line L1 is a line for supplying the raw water W1 of the water source 2 toward the pretreatment device 3. The upstream end of the raw water line L1 is connected to the water source 2 of the raw water W1. The downstream end of the raw water line L1 is connected to the pretreatment device 3. The raw water line L1 is provided with a chemical addition device 6 and a first turbidity sensor Tb1 in this order from the upstream side to the downstream side.

The chemical addition device 6 is a device for adding a chemical to the raw water W1 supplied to the pretreatment device 3. In the present embodiment, for example, as described later, when the pretreatment device 3 arranged on the downstream side of the drug addition device 6 is an iron removal manganese removal device, heavy metal ions dissolved in the raw water W1 as a drug. An oxidizing agent such as sodium hypochlorite is added to oxidize and precipitate the iron. As a control method for adding the drug in the drug addition device 6, for example, there is a control method for adding the drug at a constant rate in proportion to the flow rate of the raw water W1 supplied to the pretreatment device 3.

Further, the chemical addition device 6 sandwiches the water quality value of the raw water W1 flowing through the raw water line L1 (water treatment system 1) with a predetermined target water quality value measured by the electrode type detection unit 71 of the water quality measuring device 7 described later. Change to at least 2 or more water quality values. As a result, the calibration operation of the water quality measuring device 7 executed by the calibration execution unit 731, which will be described later, can be performed with high accuracy.

The first turbidity sensor Tb1 detects the turbidity of the raw water W1 on the upstream side of the pretreatment device 3. The turbidity is defined in JIS K0101 "Industrial Water Test Method" as "turbidity indicates the degree of turbidity of water, and is classified into visual turbidity, transmitted light turbidity, scattered light turbidity and integral sphere turbidity. To display. " The first turbidity sensor Tb1 includes, for example, a transmitted light sensor that determines the turbidity of sample water from the transmitted light intensity and a scattered light sensor that determines the degree of turbidity of the sample water based on the scattered light intensity, as shown in JIS K0101. Alternatively, an integrating sphere type sensor that determines from the ratio of the scattered light intensity to the transmitted light intensity can be used.

The pretreatment device 3 is arranged on the upstream side of the posttreatment device 5 described later. The pretreatment device 3 is a device that pretreats the raw water W1 supplied from the water source 2 on the upstream side of the posttreatment device 5. The pretreatment device 3 removes pollutants contained in the raw water W1 to produce the pretreatment water W2. Examples of the pollutant include turbid substances (for example, suspended solids such as fine particles and oxidative precipitates of dissolved iron) and organic substances grasped as total organic carbon (hereinafter, also referred to as “TOC”).

The pretreatment device 3 includes a pretreatment section side abnormality detection section 31. The pretreatment unit side abnormality detection unit 31 detects a water quality abnormality in the pretreatment device 3. When the water quality abnormality is detected by the pretreatment unit side abnormality detection unit 31, for example, when the water quality value detected by the first turbidity sensor Tb1 is out of the predetermined range, or when the water quality abnormality causes the pretreatment device 3 to detect the water quality abnormality. For example, when a blockage occurs.

Examples of the pretreatment device 3 include a sand filtration device, an iron removal manganese removal device, and the like.

When the pretreatment device 3 is a sand filtration device, the sand filtration device captures and removes suspended solids such as fine particles contained in the raw water W1 by a filter medium bed (not shown). Examples of the sand filtration device include a tower type having a filter medium bed (not shown) formed of coarse-grained filter media such as silica stone and fine-grained filter media such as anthracite and filtered sand. When a sand filtration device is used as the pretreatment device 3, it is necessary to agglomerate (flock) the suspended solids contained in the raw water W1 to facilitate removal. Therefore, the flocculant is added by the chemical addition device 6 arranged on the upstream side of the filtration tower. As the coagulant, for example, an inorganic coagulant can be used, and specific examples thereof include polyaluminum chloride (PAC) and aluminum sulfate.

When the pretreatment device 3 is an iron-removing and manganese-removing device, the iron-removing and manganese-removing device captures dissolved iron and dissolved manganese together with suspended solids such as fine particles contained in raw water W1 by a filter medium bed (not shown). And remove it. The iron-removing and manganese-removing apparatus includes a filtration tower filled with this filter medium bed. Manganese sand (fine particles carrying manganese dioxide) such as particulate manganese chamotte or manganese zeolite is usually used for the filter medium bed. When an iron-removing manganese-removing device is used as the pretreatment device 3, the dissolved iron and dissolved manganese contained in the raw water W1 are oxidized and then removed. Therefore, an oxidizing agent (for example, sodium hypochlorite) is added by the chemical adding device 6 arranged on the upstream side of the filtration tower.

The pretreatment water line L2 is a line that supplies the pretreatment water W2 treated by the pretreatment device 3 toward the posttreatment device 5. The upstream end of the pretreatment water line L2 is connected to the pretreatment device 3. The downstream end of the pretreatment water line L2 is connected to the posttreatment device 5.

The pretreated water line L2 is provided with the second turbidity sensor Tb2 and the water quality measuring device 7 in this order from the upstream side to the downstream side.

The second turbidity sensor Tb2 detects the turbidity of the pretreated water W2 on the downstream side of the pretreatment device 3. As the second turbidity sensor Tb2, the same one as the first turbidity sensor Tb1 can be used.

The water quality measuring device 7 is an apparatus that detects (measures) the water quality of the pretreated water W2 flowing through the pretreated water line L2. The water quality measuring device 7 detects the water quality of the water flowing on the downstream side of the pretreatment device 3, and also detects the water quality of the water flowing on the upstream side of the posttreatment device 5 (described later). The detected value of the water quality detected by the water quality measuring device 7 is transmitted to the control unit 10. In the present embodiment, the water quality measuring device 7 is, for example, an apparatus for detecting the residual chlorine concentration (dissolved chlorine concentration) in the water to be measured.
The details of the water quality measuring device 7 will be described later.

The post-processing device 5 is arranged on the downstream side of the pre-processing device 3. The post-treatment device 5 is a device that post-treats the pre-treatment water W2 discharged from the pre-treatment device 3 on the downstream side of the pre-treatment device 3. The post-processing device 5 includes a post-processing unit side abnormality detection unit 51. The post-treatment unit side abnormality detection unit 51 detects the water quality abnormality in the post-treatment device 5. When the water quality abnormality is detected by the post-treatment unit side abnormality detection unit 51, for example, the water quality value detected by the second turbidity sensor Tb2 on the upstream side of the post-treatment device 5 is out of the predetermined range. The case where the water quality value detected by the third turbidity sensor Tb3 on the downstream side of the aftertreatment device 5 is out of the predetermined range, the case where the aftertreatment device 5 is clogged due to the water quality abnormality, and the like can be mentioned. As the aftertreatment device 5, for example, a high-precision membrane filtration device using a hollow fiber membrane or the like is used. As the hollow fiber membrane used in the membrane filtration device, a membrane having coarser pores than a reverse osmosis membrane (also referred to as "RO membrane") is used. As a membrane module using a hollow fiber membrane, a UF membrane module having an ultrafiltration membrane, an MF membrane module having a microfiltration membrane, or the like can be applied. By using a high-precision membrane filtration device using a hollow fiber membrane, for example, Cryptosporidium (a protozoan that is hard to be killed by chlorine) can be removed.
The post-treated water W4 treated by the post-treatment device 5 is supplied to a demand point via the post-treatment water line L4.

The post-treatment water line L4 is a line for leading the post-treatment water W4 that has passed through the post-treatment device 5 to the outside of the device. The upstream side of the post-treatment water line L4 is connected to the post-treatment device 5, and the post-treatment water W4 treated by the post-treatment device 5 is supplied (delivered) to a demand point. The post-treatment water line L4 is provided with a third turbidity sensor Tb3.

The third turbidity sensor Tb3 detects the turbidity of the post-treated water W4 on the downstream side of the post-treatment device 5. The third turbidity sensor Tb3 can detect the precipitation of manganese or the like when, for example, the chemical addition device 6 does not add an oxidizing agent such as sodium hypochlorite. As the third turbidity sensor Tb3, the same one as the first turbidity sensor Tb1 can be used.

The control unit 10 is electrically connected to the pretreatment device 3, the posttreatment device 5, the chemical addition device 6, and the water quality measuring device 7. The control unit 10 controls the pretreatment device 3, the posttreatment device 5, the drug addition device 6, and the water quality measuring device 7.

The water quality measuring device 7 will be described. As shown in FIG. 2, the water quality measuring device 7 includes an electrode type detection unit 71 (electrode type detection means), a colorimetric type detection unit 72 (colorimetric type detection means), and a water quality detection control unit 73. ..

The electrode type detection unit 71 is a sensor that continuously detects the residual chlorine concentration (water quality) of the pretreated water W2 flowing through the pretreated water line L2. The electrode type detection unit 71 is an electrode type continuous measurement type (for example, polarographic electrode type) residual chlorine meter. During the operation of the water treatment system 1, the electrode type detection unit 71 continuously outputs, for example, a transmission signal of 4 to 20 mA to the control unit 10 as a detection signal.

The colorimetric detection unit 72 is a sensor that intermittently detects the residual chlorine concentration (water quality) of the pretreated water W2 flowing through the pretreated water line L2. As the colorimetric detection unit 72, for example, a colorimetric sensor that detects the residual chlorine concentration by color development when a color-developing reagent is added is used. The colorimetric detection unit 72 collects a part of the pretreated water W2, adds a coloring reagent to the collected pretreated water W2 and reacts, and measures the absorbance (color development intensity) of the pretreated water by this reaction. By doing so, the residual chlorine concentration of the pretreated water W2 is measured. Then, the colorimetric detection unit 72 measures (detects) the residual chlorine concentration in the sample water based on the measured absorbance.

The water quality detection control unit 73 controls the water quality measuring device 7. As shown in FIG. 2, the water quality detection control unit 73 includes a calibration execution unit 731 as a calibration execution means, a water quality abnormality determination unit 732, a forced detection unit 733 as a forced detection means, and a water quality abnormality control unit 734. , And a notification control unit 735.

The calibration execution unit 731 automatically calibrates the electrode type detection unit 71 based on the detected value of the water quality detected by the colorimetric detection unit 72 at a predetermined timing. In the normal time when the post-treated water W4 is manufactured in the water treatment system 1, the predetermined timing at which the calibration execution unit 731 executes the calibration operation is a periodic timing, for example, every 30 minutes. Further, the frequency of the predetermined timing at which the calibration execution unit 731 executes the calibration operation is determined according to the type of water quality detected by the water quality measuring device 7, the use of the post-treated water W4, and the like.

The calibration execution unit 731 performs a non-normal calibration operation for producing the post-treated water W4 in the water treatment system 1 by the forced detection unit 733, which will be described later, by the pretreatment unit side abnormality detection unit 31, and the water quality abnormality of the pretreatment device 3 When the water quality abnormality of the post-treatment device 5 is detected by the post-treatment unit side abnormality detection unit 51, the water quality of the water flowing through the water treatment system 1 is compared by the forced detection unit 733 described later. When the operation of forcibly detecting by the formula detection unit 72 is executed, the electrode type detection unit 71 is based on the detection value of the water quality forcibly detected by the colorimetric detection unit 72 in the forced detection unit 733 described later. Performs the action of automatically calibrating.

The calibration execution unit 731 executes an operation of calibrating the electrode type detection unit 71 based on, for example, the water quality detection value by the colorimetric detection unit 72 at each of the two or more water quality values changed by the drug addition device 6. .. Specifically, the calibration execution unit 731 detects the chlorine concentration at two points (one point at a low concentration and one point at a high concentration) sandwiching the target water quality value to be measured, for example, by the chemical addition device 6. Based on the value, a calibration curve can be taken at each of the two changed points of chlorine concentration, and calibration can be performed using the calibration curve of the two changed points. It should be noted that calibration may be performed using three or more calibration curves.

In the forced detection unit 733, when the water quality abnormality of the pretreatment device 3 is detected by the pretreatment unit side abnormality detection unit 31, or when the water quality abnormality of the posttreatment device 5 is detected by the posttreatment unit side abnormality detection unit 51. In addition, the operation of forcibly detecting the water quality of the water flowing through the water treatment system 1 by the colorimetric detection unit 72 is executed.

When the water quality abnormality determination unit 732 determines that the electrode type detection value (first detection value) is a water quality abnormality value, the forced detection unit 733 detects the electrode type detection value (first detection value) by the electrode type detection unit 71. Instead of 1 detection value), the water quality of the water flowing through the water treatment system 1 is forcibly detected as the colorimetric detection value (second detection value) by the colorimetric detection unit 72. The water quality abnormality determination unit 732 determines whether or not the electrode type detection value (first detection value) of the water quality detected by the electrode type detection unit 71 is a water quality abnormality value. For example, the water quality abnormality determination unit 732 determines that the water quality abnormality detection value (first detection value) detected by the electrode type detection unit 71 is a water quality abnormality value when it is out of a predetermined range. ..

The water quality abnormality control unit 734 has an electrode type detection value (first detection value) and a colorimetric detection value (second detection value) when the detection value detected by the electrode type detection unit 71 is a water quality abnormality value. Control to execute the operation of continuously detecting the water quality by the electrode type detection unit 71 to the control of executing the operation of intermittently detecting the water quality by the colorimetric detection unit 72 when the difference from the above value is equal to or more than a predetermined value. Performs control to switch to. Further, the water quality abnormality control unit 734 has an electrode type detection value (first detection value) and a colorimetric detection value (second detection) when the detection value detected by the electrode type detection unit 71 is a water quality abnormality value. When the difference from the value) is less than a predetermined value, the notification control unit 735 (described later) is controlled to perform control to notify the water quality abnormality. As the notification of water quality abnormality, for example, one or more of display, voice, light emission and the like can be mentioned.

The notification control unit 735 notifies an alarm when the calibration execution unit 731 executes the calibration a predetermined number of times continuously (for example, 10 times continuously) on the side where the sensitivity of the electrode type detection unit 71 is lowered or raised. To control. As the alarm notification, for example, one or more of display, voice, light emission, and the like can be mentioned. When calibration is continuously executed a predetermined number of times on the side where the sensitivity of the electrode type detection unit 71 is lowered or raised, the possibility of failure of the electrode type detection unit 71 is assumed. Therefore, the electrode type detection unit 71 can be repaired or replaced by notifying the alarm.

Next, the operation of the water quality measuring device 7 will be described.
The water quality measuring device 7 continuously determines the residual chlorine concentration (water quality) of the pretreated water W2 flowing through the pretreated water line L2 by the electrode type detection unit 71 in the normal time when the post-treated water W4 is produced in the water treatment system 1. Real-time detection.

The calibration execution unit 731 of the water quality measuring device 7 was detected by the colorimetric detection unit 72 at predetermined timings, for example, every 30 minutes in the normal time when the post-treated water W4 is produced in the water treatment system 1. Based on the detected value of the residual chlorine concentration (water quality), the operation of automatically calibrating the electrode type detection unit 71 is executed (cross check is executed). As a result, the electrode type detection unit 71 is calibrated based on the detection value of the colorimetric detection unit 72. Therefore, the residual chlorine concentration of the pretreated water W2 continuously measured by the electrode type detection unit 71 is determined. Highly reliable measured values can be obtained.

Here, the calibration execution unit 731 is configured to automatically calibrate the electrode type detection unit 71 based on the detected value of the residual chlorine concentration (water quality) detected by the colorimetric detection unit 72. I will explain the reason for this.
The electrode type detection unit 71 has an advantage that the water quality of the water flowing through the water treatment system 1 can be continuously measured, and the water quality can be measured at low cost without the need for a reagent. Therefore, the electrode type detection unit 71 can continuously measure the water quality of the water flowing through the water treatment system 1 to measure the water quality of water that fluctuates depending on the flow of water, the water temperature, and the like in real time. However, the electrode type detection unit 71 tends to have unstable measured values due to dirt on the electrodes and insufficient flow rate of sample water, and the reliability of the measured values tends to be low.

On the other hand, the colorimetric detection unit 72 can measure the water quality of the water flowing through the water treatment system 1 only intermittently, but has an advantage that the measured values are highly reliable. However, since the colorimetric detection unit 72 uses a reagent when measuring the water quality of water, if the measurement interval is shortened, the cost required for the reagent increases, and the operating cost tends to increase.

On the other hand, in the present invention, by providing the water quality measuring device 7 with the calibration execution unit 731, the electrode type detection unit 71 is automatically set based on the detected value of the water quality detected by the colorimetric detection unit 72. It was configured to perform the calibrating operation. As a result, while taking advantage of the electrode type detection unit 71, by compensating for the shortcomings of the electrode type detection unit 71 by the advantage of the colorimetric detection unit 72, both the electrode type detection unit 71 and the colorimetric detection unit 72 You can get the benefits. That is, the water quality measuring device 7 can obtain a highly reliable measurement value of the water quality of the water flowing through the water treatment system 1, which is an advantage of the colorimetric detection unit 72, and the electrode type detection unit 71. It can be measured continuously at low cost, which is an advantage.

When the surface of the electrode type detection unit 71 is automatically cleaned by the frictional resistance of the bead material, when the electrode type detection unit 71 is maintained, or when the sensor part of the electrode type detection unit 71 is replaced. In such a case, since the deviation of the measured values of the water quality measuring device 7 tends to be large, the interval of detection by the colorimetric detection unit 72 may be shortened in the calibration operation by the calibration execution unit 731.

As described above, the calibration execution unit 731 executes the calibration operation at a predetermined timing in the normal time when the post-treated water W4 is produced in the water treatment system 1. However, when the calibration execution unit 731 detects a water quality abnormality in the pretreatment device 3 by the pretreatment unit side abnormality detection unit 31 as a non-normal calibration operation for producing the post-treated water W4 in the water treatment system 1, or When the water quality abnormality of the post-treatment device 5 is detected by the post-treatment unit side abnormality detection unit 51, the water quality of the water flowing through the water treatment system 1 in the forced detection unit 733 is color-matched by the color-matching detection unit 72. The operation of forcibly detecting as a detection value (second detection value) is executed, and the electrode type detection unit is based on the water quality detection value forcibly detected by the colorimetric detection unit 72 in the forced detection unit 733. Execute the operation of automatically calibrating 71 (perform a cross check).

The reason for executing the operation of automatically calibrating the electrode type detection unit 71 when the water quality abnormality of the pretreatment device 3 or the posttreatment device 5 is detected is that the water quality abnormality occurs in the pretreatment device 3 or the posttreatment device 5. In this case, the measured value of the electrode type detection unit 71 of the water quality measuring device 7 used in the water treatment system 1 may deviate.
For example, when a water quality abnormality occurs in the pretreatment device 3, the water with the water quality abnormality flows from the pretreatment device 3 to the water quality measuring device 7, causing an abnormality in the electrode of the electrode type detection unit 71 to obtain the measured value. Perform a cross-check as there may be deviations.
Further, for example, when a water quality abnormality occurs in the aftertreatment device 5, the water with the water quality abnormality is flowing on the upstream side of the aftertreatment device 5, so that an abnormality occurs in the electrode of the electrode type detection unit 71 and the measured value. Perform a cross-check as there may be a gap.

In the present embodiment, the calibration execution unit 731 is the ratio at each of the two water quality values sandwiching the target water quality value to be the measurement target changed by the drug addition device 6 in the actual operation of calibrating the electrode type detection unit 71. The operation of calibrating the electrode type detection unit 71 is executed based on the water quality detected value by the color type detection unit 72. Specifically, the calibration execution unit 731 detects the chlorine concentration at two points (one point at a low concentration and one point at a high concentration) sandwiching the target water quality value to be measured, for example, by the chemical addition device 6. Based on the value, a calibration curve can be taken at each of the two changed points of chlorine concentration, and calibration can be performed using the calibration curve of the two changed points. As a result, the electrode type detection unit 71 can be accurately calibrated based on the water quality detection value by the colorimetric detection unit 72 by using the water quality values at two points sandwiching the target water quality value.

Further, when the water quality of the water flowing through the water treatment system 1 is abnormal, the calibration execution unit 731 does not automatically calibrate the electrode type detection unit 71, and the water quality abnormality control unit 734 controls the following. Can also be executed.

The water quality abnormality control unit 734 has an electrode type detection value (first detection value) and a colorimetric detection value (second detection value) when the detection value detected by the electrode type detection unit 71 is a water quality abnormality value. Control to execute the operation of continuously detecting the water quality by the electrode type detection unit 71 to the control of executing the operation of intermittently detecting the water quality by the colorimetric detection unit 72 when the difference from the above value is equal to or more than a predetermined value. Performs control to switch to. As a result, a highly reliable measured value can be obtained by detecting the residual chlorine concentration of the pretreated water W2 by the colorimetric detection unit 72. In this case, the length of the detection interval by the colorimetric detection unit 72 can be appropriately adjusted. When the difference between the electrode type detection value (first detection value) and the colorimetric detection value (second detection value) is equal to or greater than a predetermined value, it is assumed that the water quality has deteriorated. The interval for detecting the expression detection value (second detection value) may be shortened.

Further, the water quality abnormality control unit 734 has an electrode type detection value (first detection value) and a colorimetric detection value (second detection) when the detection value detected by the electrode type detection unit 71 is a water quality abnormality value. When the difference between the values) is less than the predetermined value, the control for notifying the water quality abnormality is executed. When the difference between the electrode type detection value (first detection value) and the colorimetric detection value (second detection value) is less than a predetermined value, the detection value detected by the electrode type detection unit 71 is correctly detected. Therefore, assuming that the detected value detected by the electrode type detection unit 71 is correct, the water quality abnormality control unit 734 controls the notification control unit 735 so as to notify the water quality abnormality to the outside.

According to the water quality measuring device 7 according to the present embodiment described above, for example, the following effects are exhibited.
In the present embodiment, an electrode type detection unit 71 that continuously detects the water quality of the water flowing through the water treatment system 1 and a colorimetric detection unit 71 that intermittently detects the water quality of the water flowing through the water treatment system 1. A calibration execution unit 731 that automatically calibrates the electrode type detection unit 71 based on the detected value of the water quality detected by the colorimetric detection unit 72 at a predetermined timing is provided.

Therefore, by combining the continuous electrode type detection unit 71 and the colorimetric colorimetric detection unit 72, the advantage of the electrode type detection unit 71 that can continuously measure the water quality at low cost and the measured value Both the advantages of the highly reliable colorimetric detection unit 72 can be obtained. As a result, highly reliable measurement values can be obtained for the water quality of the water flowing through the water treatment system 1, and continuous measurement can be performed at low cost.

Further, in the present embodiment, when the difference between the electrode type detection value (first detection value) and the colorimetric detection value (second detection value) is equal to or more than a predetermined value, the electrode type detection unit 71 continuously performs the difference. Control to switch from the control to execute the operation of detecting the water quality to the control to execute the operation of intermittently detecting the water quality by the colorimetric detection unit 72 is executed, and the electrode type detection value (first detection value) and the colorimetry are executed. A water quality abnormality control unit 734 that executes control for notifying a water quality abnormality when the difference from the expression detection value (second detection value) is less than a predetermined value is provided.

Therefore, when the electrode type detection unit 71 determines that the water quality is abnormal, the colorimetric detection unit 72 forcibly detects the water quality, and the detection value and the colorimetric type detected by the electrode type detection unit 71 are used. It can be compared with the detected value detected by the detection unit 72. Then, when the electrode type detection unit 71 is not normal, the control can be switched to the detection by the colorimetric detection unit 72. Further, when the electrode type detection unit 71 is normal, it is possible to notify the water quality abnormality by assuming that the detection value by the electrode type detection unit 71 is correct. Thereby, the water quality of the water flowing through the water treatment system 1 can be measured with high reliability.

Further, in the present embodiment, the water quality measuring device 7 detects the water quality of the water flowing downstream of the pretreatment device 3, and the pretreatment section side abnormality detecting section 31 detects the water quality abnormality of the pretreatment device 3. In this case, the forced detection unit 733 for forcibly detecting the water quality of the water flowing through the water treatment system 1 by the colorimetric detection unit 72 is provided, and the calibration execution unit 731 is compared with the forced detection unit 733. The operation of automatically calibrating the electrode type detection unit 71 is executed based on the detected value of the water quality forcibly detected by the color type detection unit 72.

Therefore, when a water quality abnormality such as a film clogging occurs in the pretreatment device 3, the electrode type detection unit 71 for detecting the measured value of the water quality on the downstream side of the pretreatment device 3 is forced by the colorimetric detection unit 72. It can be calibrated based on the detected value of the water quality detected. As a result, when it is assumed that the water quality has deteriorated on the downstream side of the pretreatment device 3, the water quality can be calibrated based on the detected value of the water quality forcibly detected by the colorimetric detection unit 72. Therefore, the water treatment system 1 It is possible to measure the quality of the water flowing through the water with high reliability.

Further, in the present embodiment, the water quality measuring device 7 detects the water quality of the water flowing on the upstream side of the post-treatment device 5, and the water quality abnormality of the post-treatment device 5 is detected by the post-treatment unit side abnormality detecting unit 51. In this case, the forced detection unit 733 for forcibly detecting the water quality of the water flowing through the water treatment system 1 by the colorimetric detection unit 72 is provided, and the calibration execution unit 731 is compared with the forced detection unit 733. The operation of automatically calibrating the electrode type detection unit 71 is executed based on the detected value of the water quality forcibly detected by the color type detection unit 72.

Therefore, when a water quality abnormality such as a film clogging occurs in the post-treatment device 5, the electrode-type detection unit 71 for detecting the measured value of the water quality on the upstream side of the post-treatment device 5 is forced by the colorimetric detection unit 72. It can be calibrated based on the detected value of the water quality detected. As a result, when it is assumed that the water quality has deteriorated on the upstream side of the aftertreatment device 5, the water quality can be calibrated based on the detected value of the water quality forcibly detected by the colorimetric detection unit 72. Therefore, the water treatment system 1 It is possible to measure the quality of the water flowing through the water with high reliability.

Further, in the present embodiment, the calibration execution unit 731 controls to notify an alarm when the calibration is continuously executed a predetermined number of times on the side of lowering or increasing the sensitivity of the electrode type detection unit 71. A control unit 735 is provided. Therefore, when calibration is continuously executed a predetermined number of times on the side where the sensitivity of the electrode type detection unit 71 is lowered or increased, the possibility of failure of the electrode type detection unit 71 is assumed. Therefore, by notifying the alarm to the outside, the maintenance worker can repair or replace the electrode type detection unit 71.

Further, in the present embodiment, the chemical addition device 6 changes the water quality value of the water flowing through the water treatment system 1 to at least two or more water quality values sandwiching a predetermined target water quality value measured by the electrode type detection unit 71. The calibration execution unit 731 executes an operation of calibrating the electrode type detection unit 71 based on the water quality detection value by the colorimetric detection unit 72 at each of the two or more water quality values changed by the drug addition device 6. To do. Therefore, the electrode type detection unit 71 can be accurately calibrated based on the water quality detection value by the colorimetric detection unit 72 by using two or more water quality values sandwiching the target water quality value.

The preferred embodiment of the present invention has been described above. However, the present invention is not limited to the above-described embodiments, and can be implemented in various forms.
For example, in the above embodiment, the water quality of the water measured by the water quality measuring device is defined as the residual chlorine concentration (dissolved chlorine concentration), but the present invention is not limited to this. Examples of the water quality of water measured by the water quality measuring device include dissolved oxygen concentration, pH concentration, calcium hardness, silica concentration, redox potential value (ORP value), and the like. In this case, the electrode type detection unit and the colorimetric type detection unit in the water quality measuring device are configured to be capable of measuring these water qualities. For example, the colorimetric detection unit is configured to detect the water quality of water using a color-developing reagent for measuring these water qualities.

Further, in the above embodiment, the water quality measuring device 7 is configured to measure the water quality of the pretreated water W2 flowing through the pretreated water line L2, but the present invention is not limited to this. The water quality measuring device may be configured to measure the water quality of the water flowing through the water treatment system 1. For example, the water quality measuring device may be configured to detect (measure) the water quality of the post-treated water W4 flowing through the post-treated water line L4.

Further, in the above-described embodiment, the water quality changing means is configured by the chemical addition device 6, but the present invention is not limited to this. For example, when the water quality measured by the water quality measuring device is the dissolved oxygen concentration, the water quality changing means may be configured by the deoxidizing device. In this case, the amount of dissolved oxygen can be adjusted by adjusting the flow rate through the decarbonizing device. When the water quality changing means is configured by an oxygen scavenger, a dissolved oxygen concentration sensor (DO sensor) is arranged on the downstream side of the oxygen scavenger.

1 Water treatment system 3 Pretreatment equipment (pretreatment section, water treatment section)
5 Post-treatment equipment (post-treatment unit, water treatment unit)
6 Chemical addition device (water quality changing means)
7 Water quality measuring device 31 Pretreatment unit side abnormality detection unit 51 Post-treatment unit side abnormality detection unit 71 Electrode type detection unit (electrode type detection means)
72 Colorimetric detection unit (colorimetric detection means)
731 Calibration execution unit 732 Water quality abnormality determination unit 733 Forced detection unit (forced detection means)
734 Water quality abnormality control unit 735 Notification control unit

Claims (5)

A water quality measuring device that measures the quality of water flowing through a water treatment system equipped with a water treatment unit.
An electrode-type detection means that continuously detects the quality of water flowing through the water treatment system, and
A colorimetric detection means for intermittently detecting the quality of water flowing through the water treatment system,
A proofing execution unit that automatically calibrates the electrode type detecting means based on the detected value of the water quality detected by the colorimetric type detecting means at a predetermined timing.
A water quality abnormality determination unit that determines whether or not the first detection value of the water quality detected by the electrode type detection means is a water quality abnormality value, and a water quality abnormality determination unit.
When the water quality abnormality determination unit determines that the first detection value is a water quality abnormality value, the water quality of the water flowing through the water treatment system is forcibly set as the second detection value by the colorimetric detection means. Forced detection means to detect and
When the difference between the first detection value and the second detection value is equal to or greater than a predetermined value, the control for continuously detecting the water quality by the electrode type detection means is interrupted by the colorimetric detection means. Water quality that executes control to switch to control that executes the operation of detecting water quality, and executes control to notify a water quality abnormality when the difference between the first detection value and the second detection value is less than a predetermined value. and abnormality control unit, water quality measurement device Ru comprising a. A water quality measuring device that measures the quality of water flowing through a water treatment system equipped with a water treatment unit.
An electrode-type detection means that continuously detects the quality of water flowing through the water treatment system, and
A colorimetric detection means for intermittently detecting the quality of water flowing through the water treatment system,
A proofing execution unit that automatically calibrates the electrode type detecting means based on the detected value of the water quality detected by the colorimetric type detecting means at a predetermined timing.
The water treatment system includes a pretreatment unit arranged on the upstream side of the water treatment unit and a pretreatment unit side abnormality detection unit that detects a water quality abnormality in the pretreatment unit.
The water quality measuring device detects the water quality of the water flowing on the downstream side of the pretreatment section, and detects the water quality.
When an abnormality in the water quality of the pretreatment unit is detected by the abnormality detection unit on the pretreatment unit side, an operation of forcibly detecting the water quality of the water flowing through the water treatment system by the colorimetric detection means is executed. Equipped with forced detection means
Wherein the calibration execution unit, said in a forced detection means based on the detected value of the force detected water quality by the colorimetric type detecting means, water quality that perform operation for automatically calibrating the electrode type detecting means measuring device. A water quality measuring device that measures the quality of water flowing through a water treatment system equipped with a water treatment unit.
An electrode-type detection means that continuously detects the quality of water flowing through the water treatment system, and
A colorimetric detection means for intermittently detecting the quality of water flowing through the water treatment system,
A proofing execution unit that automatically calibrates the electrode type detecting means based on the detected value of the water quality detected by the colorimetric type detecting means at a predetermined timing.
The water treatment system includes a post-treatment unit arranged on the downstream side of the water treatment unit and a post-treatment unit side abnormality detection unit for detecting a water quality abnormality in the post-treatment unit.
The water quality measuring device detects the water quality of the water flowing on the upstream side of the post-treatment unit, and detects the water quality.
When the water quality abnormality of the post-treatment unit is detected by the post-treatment unit side abnormality detection unit, an operation of forcibly detecting the water quality of the water flowing through the water treatment system by the colorimetric detection means is executed. Equipped with forced detection means
Wherein the calibration execution unit, said in a forced detection means based on the detected value of the force detected water quality by the colorimetric type detecting means, water quality that perform operation for automatically calibrating the electrode type detecting means measuring device. According to claim 1, the calibration execution unit includes a notification control unit that controls to notify an alarm when calibration is continuously executed a predetermined number of times on the side that lowers or raises the sensitivity of the electrode type detection means. The water quality measuring device according to any one of 3. The water treatment system includes a water quality changing means for changing the water quality value of the water flowing through the water treatment system to at least two or more water quality values sandwiching a predetermined target water quality value measured by the electrode type detecting means.
The proofreading execution unit executes an operation of calibrating the electrode type detection means based on the water quality detected by the colorimetric detection means at each of the two or more water quality values changed by the water quality changing means. Item 4. The water quality measuring device according to any one of Items 1 to 4.

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