JP2011169859A - Method and device for automatically managing chlorine concentration - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an automatic management device of chlorine concentration for continuously managing chlorine concentration accurately even without any calibration mechanisms of an electrode for detecting chlorine concentration. <P>SOLUTION: The automatic management device M includes: a chlorine concentration meter A for measuring the concentration of free residual chlorine, or the like of a sampling liquid collected from a treatment liquid circulation system L by an automated absorptiometry by spacing some time; an oxidation-reduction potentiometer B for measuring an oxidation/reduction potential of the sampling liquid; a control part C for correlating a concentration change in the concentration of free residual chlorine, or the like measured by the chlorine concentration meter A with a change in oxidation/reduction potential, or the like measured by the oxidation-reduction potentiometer B for calculating a prediction control coefficient of the concentration of free residual chlorine, or the like for calculating concentration of chlorine for control predicted by the prediction control coefficient and the most recent oxidation-reduction potential, and calculating a control signal based on the concentration of chlorine for control for output; and a chlorine concentration adjustment part D for adjusting the concentration of free residual chlorine, or the like of the treatment liquid circulation system by the control signal from the control part C. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an automatic chlorine concentration management method and an automatic management apparatus for continuously and automatically managing a chlorine concentration in a treatment liquid circulation system using an automated spectrophotometric chlorine concentration meter and an oxidation-reduction potentiometer.

  In order to maintain the water quality of the water in the baths and pools of public baths, solid chlorine agent (salach powder) and sodium hypochlorite (NaClO) are manually added to reduce the free chlorine concentration. It is manually measured and maintained at the specified value. However, in manual measurement and manual input, it is difficult to always manage at a constant concentration, which tends to result in insufficient input or excessive input.

  Recently, there is an example in which an automatic management method by continuous feedback control using a polarographic residual chlorine sensor is performed, but it is necessary to manually calibrate the electrode periodically, which is very laborious.

  Moreover, the water treatment apparatus has an electrolysis tank for electrolytically treating water and imparting a sterilizing action, and supplies water sterilized by supplying water electrolyzed in the electrolysis tank to a water tank such as a pool. The residual chlorine concentration in the water tank is continuously obtained using the first and second two residual chlorine concentration detecting means and the first residual chlorine concentration detecting means for obtaining the residual chlorine concentration of the water in the tank. In addition, a residue for adjusting the supply rate to the water tank of the sterilizing component containing chlorine, which is generated by electrolytic treatment of water in the electrolytic tank, based on the result of the residual chlorine concentration of water obtained above. Using the chlorine concentration control means and the second residual chlorine concentration detection means, the residual chlorine concentration of the water in the tank is obtained regularly or irregularly, and the result is obtained as the residual chlorine obtained by the first residual chlorine concentration detection means. When there is a deviation between the two compared to the concentration Water treatment apparatus is known and a calibration control means for calibrating the first residual chlorine concentration detection means (for example, see Patent Document 1).

  The first residual chlorine concentration detecting means outputs a change in the residual chlorine concentration of water as a change in the value of the current flowing between the electrodes, and has a function of calibrating this output by adjusting the span between the electrodes. The calibration control means adjusts the span between the electrodes so that the residual chlorine concentration obtained from the output current value of the residual chlorine sensor matches the residual chlorine concentration obtained by the second residual chlorine concentration detecting means. Like to do. The second residual chlorine concentration detecting means outputs the change in the residual chlorine concentration of water as the change in the absorbance with the discoloration of the DPD reagent.

Japanese Patent No. 39999967 (pages 11-12, FIGS. 6-9)

  The first residual chlorine concentration detecting means outputs a change in the residual chlorine concentration of water as a change in the current value flowing between the electrodes, and has a function of calibrating this output by adjusting the span between the electrodes. It is a sensor, and it is necessary to constantly measure the residual chlorine concentration with this residual chlorine sensor.

  Further, the calibration control means adjusts the span between the electrodes so that the residual chlorine concentration obtained from the output current value of the residual chlorine sensor coincides with the residual chlorine concentration obtained by the second residual chlorine concentration detecting means. Therefore, a troublesome mechanism for calibrating the electrode for detecting the chlorine concentration is required.

  The present invention has been made in view of the above points, and an automatic chlorine concentration management method and an automatic management device capable of performing accurate continuous chlorine concentration management without a chlorine concentration detection electrode calibration mechanism. The purpose is to provide.

  The invention described in claim 1 measures the chlorine concentration of the sampling solution collected from the processing solution circulation system over time by an automated spectrophotometric method, and continuously measures the oxidation-reduction potential of the sampling solution. During the measurement by the absorptiometry, the control chlorine is predicted to be optimally controlled by using the change in the redox potential corresponding to the change in the chlorine concentration obtained by the absorptiometry. This is an automatic chlorine concentration management method in which the concentration is calculated and the chlorine concentration in the treatment liquid circulation system is continuously controlled based on this control chlorine concentration.

  In the invention described in claim 2, the free residual chlorine concentration or the residual chlorine concentration of the sampling liquid collected from the processing liquid circulation system is measured with a time interval by an absorptiometric method using an automated diethyl-p-phenylenediamine reagent. Chlorine concentration meter, oxidation-reduction potentiometer that measures the oxidation-reduction potential of the sampling solution, concentration change of free residual chlorine concentration or residual chlorine concentration of the sampling solution measured with the chlorine concentration meter by the absorptiometry, and the oxidation-reduction The prediction control coefficient of the free residual chlorine concentration or the residual chlorine concentration is calculated by associating the oxidation-reduction potential of the sampling solution measured by the electrometer with the change of the corrected oxidation-reduction potential value corrected by the liquid temperature of this sampling solution, Based on this predictive control coefficient and the latest oxidation-reduction potential, the predicted control chlorine concentration for optimal control is calculated. A control unit that calculates and outputs a control signal for feedback control of the free residual chlorine concentration or the residual chlorine concentration in the treatment liquid circulation system to a preset set value based on the control chlorine concentration, and the control unit that outputs the control signal It is an automatic chlorine concentration management device comprising a free residual chlorine concentration or a chlorine concentration adjusting unit for adjusting a residual chlorine concentration in a processing liquid circulation system according to a control signal.

  According to a third aspect of the present invention, there is provided the chlorine concentration automatic management apparatus according to the second aspect, wherein an automated spectrophotometric chlorine concentration meter using a diethyl-p-phenylenediamine reagent is provided in a plurality of treatment liquid circulation systems. One is provided, and the chlorine concentration meter sequentially measures the free residual chlorine concentration or the residual chlorine concentration of a plurality of sampling solutions supplied by switching from a plurality of processing liquid circulation systems. Are provided for each of the treatment liquid circulation systems, and each measure the oxidation-reduction potential of a plurality of sampling liquids.

  According to the first aspect of the present invention, an accurate chlorine concentration can be measured by an automated spectrophotometric method, and a change in the concentration of the chlorine concentration obtained by the spectrophotometric measurement can be accommodated during the measurement by the spectrophotometric method. The chlorine concentration for control that is predicted to be optimally controlled using the change in the oxidation-reduction potential is calculated, and the chlorine concentration in the processing liquid circulation system is continuously controlled based on this control chlorine concentration, so the chlorine concentration detection Even without an electrode calibration mechanism, accurate chlorine concentration can be continuously managed by absorptiometry.

  According to the invention described in claim 2, it is possible to measure an accurate free residual chlorine concentration or a residual chlorine concentration with a time by a chlorine concentration meter by an automated spectrophotometric method, and during the measurement by the chlorine concentration meter, The free residual chlorine concentration corresponding to the exact free residual chlorine concentration or the change in residual chlorine concentration and the change in the corrected redox potential value obtained by correcting the redox potential measured by the redox potential meter with the liquid temperature, etc. Calculate the predictive control coefficient of chlorine concentration or residual chlorine concentration, calculate the control chlorine concentration predicted for optimal control by this predictive control coefficient and the latest oxidation-reduction potential, and based on this control chlorine concentration Because it calculates and outputs a control signal that feedback-controls the free residual chlorine concentration or residual chlorine concentration in the treatment liquid circulation system to a preset value, it can be used for chlorine concentration detection. It is possible to perform continuous control of the exact free residual chlorine concentration or residual chlorine concentration by also absorption photometry without pole calibration mechanism.

  According to the invention described in claim 3, one of the expensive and automated spectrophotometric chlorine concentration meters can be effectively used for a plurality of processing liquid circulation systems.

It is a circuit diagram showing one embodiment of an automatic management method and automatic management device of chlorine concentration concerning the present invention. It is a circuit diagram of the whole system to which the same automatic management apparatus is applied. It is a flowchart which shows the control procedure of an automatic management apparatus same as the above. It is a circuit diagram which shows other embodiment of an automatic management apparatus same as the above.

  Hereinafter, the present invention will be described in detail with reference to one embodiment shown in FIGS. 1 to 3 and another embodiment shown in FIG.

  As shown in FIG. 2, the piping drawn out from the processing liquid tank T such as a bathtub or a pool is returned to the processing liquid tank T through the circulation pump P and the filter F, thereby forming the processing liquid circulation system L. is doing. The sample pipe Li for extracting the sampling liquid from the processing liquid circulation system L is drawn, and the free residual chlorine concentration or residual chlorine concentration as the chlorine concentration (the concentration of the total residual chlorine combined with the free residual chlorine and the combined residual chlorine) It is drawn into an automatic management device M that automatically manages “residual chlorine concentration”. A hypochlorite injection pipe Lo for supplying sodium hypochlorite to the treatment liquid circulation system is drawn out from the automatic management apparatus M and drawn into the treatment liquid circulation system L.

  As shown in FIG. 1, the free residual chlorine concentration or the automatic management device M for residual chlorine concentration is a free residual of sampling solution collected from a processing solution circulation system by an absorptiometric method using an automated diethyl-p-phenylenediamine reagent. Between the chlorine concentration meter A that measures the chlorine concentration or the residual chlorine concentration with time, the oxidation-reduction potentiometer B that measures the oxidation-reduction potential of the sampling solution, and the measurement by the absorptiometry, the absorptiometry is used. Calculate the control chlorine concentration predicted for optimal control using the above-mentioned change in redox potential corresponding to the change in free residual chlorine concentration or residual chlorine concentration obtained by measurement. A control unit C that calculates and outputs a control signal for continuously controlling the free residual chlorine concentration or the residual chlorine concentration of the processing liquid circulation system L based on the concentration; It has and a chlorine concentration adjusting unit D for adjusting the free residual chlorine concentration or residual chlorine concentration of the treatment liquid circulation system by the force control signal.

  That is, the control unit C is configured to measure the free residual chlorine concentration or the change in the residual chlorine concentration of the sampling solution measured with the spectrophotometric chlorine concentration meter A and the sampling measured by the redox electrometer B. Using the oxidation-reduction potential of the liquid as a predicted measurement value, the predicted redox potential is correlated with the change in the corrected oxidation-reduction potential value corrected by the liquid temperature of the sampling liquid, etc. A predictive control coefficient is calculated, and this is the latest predictive coefficient measured with the predictive control coefficient and the oxidation-reduction potentiometer B except when the free residual chlorine concentration or residual chlorine concentration is measured with the chlorine concentration meter A by the spectrophotometry. The control chlorine concentration that is predicted to be optimally controlled by the oxidation-reduction potential is calculated. Based on this control chlorine concentration, the concentration of free residual chlorine in the treatment liquid circulation system is calculated. Or the residual chlorine concentration is calculated a control signal for feedback control so that the predetermined set value and outputs.

  The spectrophotometric chlorine concentration meter A is a measuring device for free residual chlorine concentration or residual chlorine concentration obtained by automating the diethyl-p-phenylenediamine method (so-called DPD method). Measures the concentration of free residual chlorine or total residual chlorine in public bath tub water, pools, tap water, etc., by measuring the concentration of residual chlorine, or the total residual chlorine concentration of free residual chlorine and combined residual chlorine This is an official method, in which diethyl-p-phenylenediamine reagent (so-called DPD reagent) is mixed with the sampling solution to develop color, and then the absorbance of the sampling solution is measured to automatically determine the free residual chlorine concentration or residual chlorine concentration. taking measurement.

  That is, the automatic management device M can automatically manage the concentration of only free residual chlorine, and automatically change the concentration of residual chlorine and bound residual chlorine by changing the DPD reagent or adding the DPD reagent. It can also be managed.

  The absorptiometry part A1 of the chlorine concentration meter A is provided with a stirrer 2 in the lower part of the absorbance cell 1, the sample tube Li is connected to the lower part of the absorbance cell 1 through the sample water electromagnetic valve 3, and the absorbance cell 1 The light-emitting device 4 and the light-receiving device 5 are arranged opposite to each other on the left and right sides, and a pipe for supplying the DPD reagent 7 by the DPD reagent metering pump 6 is connected to the absorbance cell 1. On the other hand, a pipe for supplying a phosphate buffer solution 9 that suppresses fluctuations in pH by a phosphate buffer solution pump 8 is connected.

  This automated spectrophotometer chlorine concentration meter A supplies the DPD reagent 7 into the absorbance cell 1 by the DPD reagent metering pump 6 to cause color development and at the same time, phosphate buffer by the phosphate buffer metering pump 8. The liquid 9 is supplied, and the DPD reagent 7 and the phosphate buffer 9 are stirred with the sampling liquid by the stirrer 2 to stabilize the color development state. From the light emitter 4, depending on the free residual chlorine concentration or the residual chlorine concentration with the DPD reagent The absorbance of the sampling solution is measured from the intensity of the light that has passed through the colored sampling solution and reaches the light receiver 5, and the free residual chlorine concentration or residual chlorine concentration is automatically measured. Although a measurement value relating to the concentration or residual chlorine concentration can be obtained, a certain amount of sampling solution is once stored and the DPD reagent is uniformly stirred by the stirrer 2 For pitch type, not suitable for continuous measurement can not cope when free residual chlorine concentration or residual chlorine concentration is rapidly changing.

  On the other hand, the measuring part B1 of the oxidation-reduction potentiometer B has two electrodes (hereinafter referred to as ORP electrodes) 10 for measuring the oxidation-reduction potential provided inside the ORP electrode holder 11, and the water sample tube Li is a sample. It is connected to the lower part of the ORP electrode holder 11 through the water regulating valve 12.

  The ORP electrode 10 is an electrode that measures an oxidation-reduction potential, that is, a potential difference (voltage) capable of measuring the oxidizing power or reducing power of a substance by the potential difference between the two electrodes of the comparison electrode and the measurement electrode. + Represents oxidizing power. Compared to polarographic electrodes that measure the chlorine concentration based on the value of the current that flows between electrodes at a constant voltage, this electrode is simple and inexpensive, but it is an electrode for measuring the redox power, and it accurately measures the chlorine concentration. Therefore, it is easily affected by other effects and is difficult as a single chlorine concentration meter. On the other hand, since the oxidation-reduction potential obtained by the ORP electrode 10 changes depending on the chlorine concentration, the chlorine concentration value can be estimated by the degree of change in the chlorine concentration, and more accurate by considering the liquid temperature, pH, etc. It is well possible to predict the concentration change. Factors that do not undergo rapid changes such as pH and electrode aging are included in the redox potential measurement and are not affected.

  The chlorine concentration adjusting unit D is for injecting sodium hypochlorite 13 into the treatment liquid circulation system L via the injection check valve 15 by the hypochlorite injection metering pump 14 and is output from the control unit C. The pump discharge amount of the hypochlorite injection metering pump 14 is controlled by the control signal, and the hypochlorite injection amount to the processing liquid circulation system L is determined according to the pump discharge amount.

  In the control unit C, a chlorine concentration calculation unit 17 that calculates free residual chlorine concentration or residual chlorine concentration from the absorbance data obtained by the absorbance measurement unit A1 of the chlorine concentration meter A, and ORP electrode conversion of the oxidation-reduction potentiometer B Is connected to the controller 19 and is converted by the free residual chlorine concentration or residual chlorine concentration (referred to as DPD chlorine concentration) calculated by the chlorine concentration calculation unit 17 and the ORP electrode converter 18 of the oxidation-reduction potentiometer B. The redox potential (referred to as ORP value) is input to the controller 19. The DPD chlorine concentration obtained by the chlorine concentration calculation unit 17 is recorded by a recorder 20 connected to the chlorine concentration calculation unit 17.

  A temperature sensor 21 for detecting the liquid temperature of the sampling liquid is connected to the test pipe Li, and a data acquisition line obtained by the temperature sensor 21 is connected to the controller 19 of the control unit C. When the liquid temperature of the processing liquid circulation system is controlled to be constant, the liquid temperature may be input to the controller 19 of the control unit C, and a temperature sensor for managing the chlorine concentration is not necessary.

  The controller 19 of the controller C measures the change in free residual chlorine concentration or residual chlorine concentration (DPD chlorine concentration) of the sampling solution measured by the chlorine concentration meter A by the above-mentioned spectrophotometry and the above redox electrometer B. Prediction of free residual chlorine concentration or residual chlorine concentration by correlating with a change in a corrected oxidation-reduction potential value (referred to as a corrected ORP value) obtained by correcting the oxidation-reduction potential (ORP value) of the sampling solution according to the liquid temperature of the sampling solution. A control coefficient (referred to as a predicted control coefficient) is calculated, and a control chlorine concentration (referred to as a control chlorine concentration) that is predicted to be optimally controlled by the predicted control coefficient and the latest ORP value is calculated. Based on the chlorine concentration, a control signal for feedback control of the free residual chlorine concentration or residual chlorine concentration in the treatment liquid circulation system to a preset set value is calculated. It has a function to be.

  That is, the controller 19 of the control unit C compares the calculated control chlorine concentration with the preset value of the DPD chlorine concentration set in advance, so that the difference is eliminated, and the hypochlorite injection metering pump 14 Is provided with a calculation / control function for calculating and outputting a control signal for feedback control of the pump discharge amount (the hypochlorite injection amount into the processing liquid circulation system L).

  As described above, the automatic management method using the automatic management apparatus M uses the ORP value suitable for continuous control such as pump control based on the DPD chlorine concentration that can ensure the measurement accuracy. The correction ORP value for predicting the DPD chlorine concentration is calculated by correcting the liquid temperature, etc., and the correction of the correction ORP value to the DPD chlorine concentration is corrected by associating the change of the correction ORP value with the concentration change of the DPD chlorine concentration. Calculates the predictive control coefficient, which is a coefficient, calculates the chlorine concentration for control by applying this predictive control coefficient to the latest ORP value, and does not allow continuous measurement because of the batch measurement method. Is compensated by this control chlorine concentration, and the pump discharge amount and the like are continuously controlled.

  Next, FIG. 3 shows a calculation flow for calculating the supplemental chlorine concentration. The circled numbers in FIG. 3 are step numbers indicating control procedures.

(Step 1)
Accurate DPD chlorine concentration a1 (mg / L) is measured by a chlorine concentration meter A by an automated spectrophotometric method. The DPD chlorine concentration a1 (mg / L) is recorded by the recorder 20.

(Step 2)
Based on the difference between the DPD chlorine concentration a1 (mg / L) measured with the chlorine concentration meter A by the absorptiometry and the DPD chlorine concentration set value, a control signal for controlling the discharge amount of the hypochlorite injection metering pump 14 is provided. Calculated by the controller 19 and output. For example, when the DPD chlorine concentration a1 (mg / L) is lower than the DPD chlorine concentration set value, the discharge amount of the hypochlorite injection metering pump 14 is increased according to the degree, and the hypochlorite injection metering pump Increase the injection amount of sodium hypochlorite 13 injected into the processing liquid circulation system L from 14 through the check valve 15 for injection, and conversely, the DPD chlorine concentration a1 (mg / L) When it exceeds, the discharge amount of the hypochlorite injection metering pump 14 is reduced according to the degree, and in some cases it is stopped.

(Step 3)
Always determine whether a certain amount of time has passed since the previous measurement of the chlorine concentration meter A by the spectrophotometric method, and execute the measurement of the chlorine concentration meter A by the spectrophotometric method every certain time, for example every hour To do. During the measurement of the chlorine concentration meter A by the absorptiometry, the control procedure after step 4 is entered.

(Step 4)
When the measurement of the chlorine concentration meter A by the absorptiometry is not performed, the ORP value b (mV) for predicting the DPD chlorine concentration is measured by the oxidation-reduction potentiometer B.

(Step 5)
The liquid temperature t (K) for predicting the DPD chlorine concentration detected by the temperature sensor 21 is measured.

(Step 6)
It is determined whether or not the DPD chlorine concentration a1 (mg / L) has been newly measured by the measurement of the chlorine concentration meter A by the absorptiometry in steps 1 to 3.

(Step 7)
When DPD chlorine concentration a1 (mg / L) is newly measured by the spectrophotometric measurement in step 6, the DPD chlorine concentration corresponding to the latest change in DPD chlorine concentration a1 (mg / L) obtained. Calculate how much the predicted correction ORP value corrected by the ORP value b (mV) for prediction and the liquid temperature t (K) has changed, and the concentration change of this DPD chlorine concentration a1 (mg / L) A predictive control coefficient X is calculated from the correspondence with the change in the corrected ORP value.

  For example, the latest change in the DPD chlorine concentration a1 (mg / L) and the change in the corrected ORP value obtained by correcting the ORP value b (mV) for predicting the DPD chlorine concentration at that time by the liquid temperature t (K), etc. And a predicted control coefficient X that can predict a change in the DPD chlorine concentration a1 (mg / L) is calculated by multiplying the change value of the corrected ORP value by the predicted control coefficient X.

  The predictive control coefficient X is preferably determined by averaging a plurality of data.

(Step 8)
The predicted control chlorine concentration a2 (mg / L) is calculated by applying the predicted control coefficient X to the latest DPD chlorine concentration prediction ORP value b (mV). For example, the control chlorine concentration a2 (mg / L) predicted by multiplying the latest ORP value b (mV) by the predicted control coefficient X is calculated. When the liquid temperature t (K) or the like changes, the predicted control coefficient X is applied to a value obtained by correcting the ORP value b (mV) with the liquid temperature or the like.

(Step 9)
From the difference between the control chlorine concentration a2 (mg / L) obtained in step 8 and the DPD chlorine concentration set value, the controller 19 calculates a control signal for controlling the discharge amount of the hypochlorite injection metering pump 14. Output. For example, when the control chlorine concentration a2 (mg / L) is lower than the DPD chlorine concentration set value, the discharge amount of the hypochlorite injection metering pump 14 is increased according to the degree, and the hypochlorite injection fixed amount The injection amount of sodium hypochlorite 13 injected from the pump 14 through the check valve 15 for injection into the processing liquid circulation system L is increased.

  The predictive control coefficient X has an auto-tuning function so that the difference between the actually measured DPD chlorine concentration a1 (mg / L) and the control chlorine concentration a2 (mg / L) is reduced. Optimal control is possible.

  As described above, according to the embodiment shown in FIG. 1 to FIG. 3, the accurate DPD chlorine concentration a1 can be measured by the absorptiometry, and the interval between the absorptiometry can be obtained by the absorptiometry. The control chlorine concentration a2 is calculated using the change in the ORP value b corresponding to the change in the DPD chlorine concentration a1, and the free residual chlorine concentration or residual in the processing liquid circulation system L is calculated based on the control chlorine concentration a2. Since the chlorine concentration is continuously controlled, the accurate free residual chlorine concentration or residual chlorine concentration can be continuously managed by the absorptiometry without the conventional calibration mechanism of the chlorine concentration detection electrode.

  That is, while it is possible to measure the accurate DPD chlorine concentration a1 with time by the chlorine concentration meter A by the absorptiometry, and while the measurement by the chlorine concentration meter A cannot be performed, the controller 19 of the control unit C performs the above accurate measurement. A prediction control coefficient X is obtained by associating the change in the DPD chlorine concentration a1 with the change in the correction ORP value for predicting the DPD chlorine concentration obtained by correcting the ORP value b of the sampling solution measured by the oxidation-reduction potentiometer B with the solution temperature t. And the control chlorine concentration a2 predicted by the predicted control coefficient X and the latest ORP value b is calculated. Based on this control chlorine concentration a2, the controller 19 of the control unit C determines the treatment liquid circulation system. The control signal for feedback control of the free residual chlorine concentration or residual chlorine concentration to a preset set value is calculated and output, so even without the chlorine concentration detection electrode calibration mechanism It is possible to perform continuous control of the exact free residual chlorine concentration or residual chlorine concentration by degrees method. In short, unlike the polarographic electrode, which requires manual adjustment of the span between the electrodes, continuous measurement with the simple and inexpensive ORP electrode 10 can automatically compensate for highly reliable DPD chlorine concentration with high accuracy. .

  Next, FIG. 4 shows another embodiment.

  As shown in FIG. 4, the pipes drawn from a plurality of treatment liquid tanks T1, T2, T3 such as a bathtub and a pool are connected to respective circulation pumps P1, P2, P3 and respective filters F1, F2, After passing through F3, they are returned to the respective treatment liquid tanks T1, T2, and T3 to constitute respective treatment liquid circulation systems L1, L2, and L3. An automatic management device M1, M2, M3 for automatically managing each free residual chlorine concentration or residual chlorine concentration is drawn out from each processing liquid circulation system L1, L2, L3, and a sampling pipe Li for extracting each sampling liquid is drawn out. Has been drawn into. From each of the automatic management devices M1, M2, M3, hypochlorite injection pipes Lo for supplying sodium hypochlorite to the respective treatment liquid circulation systems L1, L2, L3 are drawn out, and the respective treatment liquid circulation systems. It is drawn into L1, L2, and L3.

  The spectrophotometric measurement unit A1 and the chlorine concentration calculation unit 17 (see FIG. 1) of the chlorine concentration meter A by the spectrophotometry method are provided in only one automatic management device M1 for the plurality of processing liquid circulation systems L1, L2, and L3. It has been.

  The test pipes Li2 and Li3 are drawn from the test pipe Li for sampling liquid sampling of the processing liquid circulation systems L2 and L3, and these test pipes Li2 and Li3 are automatically managed via the sample water solenoid valves 23 and 24, respectively. It is connected to a pipe line between the absorbance measuring unit A1 of the apparatus M1 and the sample water electromagnetic valve 3.

  Then, by opening the sample water solenoid valve 3 and closing the sample water solenoid valves 23, 24, the sample water of the treatment liquid circulation system L1 is supplied to the absorptiometry unit A1, and the sample water solenoid valve 23 is opened, By closing the sample water solenoid valve 3, 24, the sample water of the processing liquid circulation system L2 is supplied to the absorptiometry unit A1, and the sample water solenoid valve 24 is opened and the sample water solenoid valve 3, 23 is closed. Then, the sample water of the treatment liquid circulation system L3 is supplied to the absorptiometry unit A1. In this way, the processing solutions of the plurality of processing solution circulation systems L1, L2, and L3 are sequentially switched and supplied to the common absorptiometry unit A1, and the absorptiometry unit A1 and the chlorine concentration calculator 17 (see FIG. 1). ), The residual chlorine concentration or residual chlorine concentration (referred to as DPD chlorine concentration) of the plurality of treatment liquid circulation systems L1, L2, and L3 is sequentially measured.

  On the other hand, the measuring units B1, B2, B3 of the oxidation-reduction potentiometer B and the ORP electrode converter 18 (see FIG. 1) corresponding thereto are respectively provided with respective automatic management devices M1 for the plurality of processing liquid circulation systems L1, L2, L3. , M2 and M3, and the oxidation-reduction potentials (referred to as ORP values) of the respective treatment liquid circulation systems L1, L2 and L3 are measured.

  As shown in FIG. 4, when there are a plurality of treatment liquid tanks T1, T2, and T3 to be measured, a sample water line to the absorptiometry unit A1 is connected via sample water solenoid valves 3, 23, and 24. Then, the concentration is measured with one chlorine concentration meter A. This chlorine concentration meter A is suitable for sequentially measuring the free residual chlorine concentration or residual chlorine concentration of a plurality of processing liquid circulation systems L1, L2, and L3 for batch type measurement. On the other hand, the measuring parts B1, B2, B3 of the oxidation-reduction potentiometer B are suitable for real-time control by being installed in the treatment liquid circulation systems L1, L2, L3 of the tanks T1, T2, T3, respectively.

  According to the embodiment shown in FIG. 4, one of the expensive automated spectrophotometric chlorine concentration meters A can be effectively used for a plurality of processing liquid circulation systems L1, L2, and L3. DPD chlorine obtained by absorptiometric measurement by constantly monitoring changes in the ORP values b of a plurality of processing liquid circulation systems L1, L2, and L3 with an inexpensive redox electrometer B The control chlorine concentration a2 is calculated using the change in the ORP value b corresponding to the concentration change of the concentration a1, and the free residual chlorine concentration or residual in the treatment liquid circulation systems L1, L2, L3 is calculated based on the control chlorine concentration a2. Since the chlorine concentration is continuously controlled, the accurate free residual chlorine concentration or residual chlorine concentration can be continuously managed by the absorptiometry without the conventional calibration mechanism of the chlorine concentration detection electrode.

  The present invention can be used in industries related to the manufacture and sale of a free residual chlorine concentration or a residual chlorine concentration automatic management device M in a processing liquid circulation system.

A Chlorine concentration meter by automated spectrophotometry B Redox potentiometer C Control unit D Chlorine concentration adjustment unit L, L1, L2, L3 Treatment liquid circulation system

Claims (3)

While measuring the chlorine concentration of the sampling liquid collected from the processing liquid circulation system by automated spectrophotometry over time, the redox potential of the sampling liquid is continuously measured,
During the measurement by the absorptiometry, the chlorine concentration for control that is predicted for optimal control using the change in the redox potential corresponding to the change in the concentration of chlorine obtained by the absorptiometry To calculate
An automatic chlorine concentration management method characterized by continuously controlling the chlorine concentration of the treatment liquid circulation system based on the chlorine concentration for control. A chlorine concentration meter that measures the free residual chlorine concentration or residual chlorine concentration of a sampling solution collected from a processing solution circulation system by an absorptiometric method using an automated diethyl-p-phenylenediamine reagent with a time interval;
An oxidation-reduction potentiometer for measuring the oxidation-reduction potential of the sampling solution;
The free residual chlorine concentration of the sampling solution measured with the chlorine concentration meter by the absorptiometry or the change in residual chlorine concentration and the oxidation-reduction potential of the sampling solution measured with the oxidation-reduction potentiometer were corrected by the temperature of the sampling solution. Predictive control coefficient of free residual chlorine concentration or residual chlorine concentration is calculated in correspondence with the change of corrected redox potential value, and control is predicted to optimally control by this predictive control coefficient and the latest redox potential A control unit that calculates a chlorine concentration for use and calculates and outputs a control signal that feedback-controls the free residual chlorine concentration or the residual chlorine concentration in the processing liquid circulation system to a preset value based on the control chlorine concentration; ,
An automatic chlorine concentration management device comprising: a free residual chlorine concentration or a chlorine concentration adjusting unit for adjusting a free residual chlorine concentration or a residual chlorine concentration in a processing liquid circulation system according to a control signal output from the control unit. One automated chlorine-concentration meter using diethyl-p-phenylenediamine reagent is provided for a plurality of treatment liquid circulation systems, and this chlorine concentration meter is sequentially switched from a plurality of treatment liquid circulation systems and supplied. Measure the free residual chlorine concentration or residual chlorine concentration of multiple sampled solutions sequentially,
The chlorine concentration automatic management device according to claim 2, wherein the oxidation-reduction potentiometer is provided for each of the plurality of processing liquid circulation systems, and measures the oxidation-reduction potential of each of the plurality of sampling liquids.

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