Pollution load monitoring system and pollution load grasping method

Abstract

To provide a pollution load monitoring system which can automatically acquire and monitor a BOD conversion value (pollution load information) of inflow water flowing into an aeration tank.SOLUTION: A pollution load remote monitoring system 1, which acquires pollution load information in a wastewater treatment facility 2 provided with an aeration tank 25, includes: a turbidity meter which measures the turbidity of aeration tank inflow water, which is inflow water flowing into the aeration tank 25; an electric conductivity meter which measures the electric conductivity of the aeration tank inflow water; and an arithmetic device 11 which calculates a BOD conversion value on the basis of measured values of the turbidity meter and the electric conductivity meter. When the BOD conversion value exceeds a predetermined value, the monitoring system outputs alarm information (transmits it to an information processing device 4).SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a pollution load monitoring system for acquiring pollution load information in a wastewater treatment facility equipped with an aeration tank for an activated sludge process, and a method for grasping the pollution load. [Background technology]

[0002] In various types of treatment facilities, the operating conditions and the like are monitored. As a related technique, Patent Document 1 discloses a technique relating to an operation management device for a water treatment plant that manages the operation of the water treatment plant based on at least two items of data indicating the operating state of the water treatment plant. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2008-250805 A Summary of the Invention [Problem to be solved by the invention]

[0004] One of the pieces of information needed to optimize the operation of wastewater treatment facilities is pollution load information, which shows fluctuations in the quality of treated water. By understanding the level of pollution load (amount of organic matter), it is possible to determine more appropriate operating conditions. In wastewater treatment facilities equipped with an aeration tank, the BOD (Biochemical Oxygen Demand) of the inflow water into the aeration tank is used as pollution load information. However, BOD is measured by controlling the temperature of sample water in a thermostatic chamber for a certain period of time (5 days for BOD5), measuring the amount of oxygen before and after that, and calculating the amount of oxygen consumed. Conventionally, sample water was obtained and measured at an analysis laboratory, so it was difficult to measure in real time, and it was difficult to capture and analyze fluctuations over time, for example.

[0005] In view of the above, an object of the present invention is to provide a pollution load monitoring system capable of automatically acquiring and monitoring the BOD equivalent value (pollution load information) of inflow water flowing into an aeration tank. [Means for solving the problem]

[0006] (Configuration 1) A monitoring system for acquiring pollution load information in a wastewater treatment facility equipped with an aeration tank, comprising: a turbidity meter for measuring the turbidity of aeration tank inflow water, which is the water flowing into the aeration tank; a conductivity meter for measuring the conductivity of the aeration tank inflow water; and a calculation device for calculating a BOD equivalent value based on the measurement values ​​of the turbidity meter and the conductivity meter.

[0007] (Configuration 2) 2. The pollution load monitoring system according to claim 1, wherein, when the BOD conversion value exceeds a predetermined value, alarm information is output.

[0008] (Configuration 3) A pollution load monitoring system as described in configuration 1 or 2, in which first correlation information, which is correlation information between the measurement values ​​of the turbidity meter and the conductivity meter and COD, and second correlation information, which is correlation information between COD and BOD, are each set in advance, and a COD equivalent value is calculated using the first correlation information based on the measurement values ​​of the turbidity meter and the conductivity meter, and the BOD equivalent value is calculated using the second correlation information based on the COD equivalent value.

[0009] (Configuration 4) A pollution load monitoring system according to configuration 3, wherein the first correlation information is a multiple regression equation, the system having a first multiple regression equation and a second multiple regression equation, and when the COD conversion value calculated using the first multiple regression equation based on measurement values ​​of the turbidity meter and the conductivity meter is equal to or greater than a threshold value, the COD conversion value is recalculated using the second multiple regression equation based on measurement values ​​of the turbidity meter and the conductivity meter.

[0010] (Configuration 5) A pollution load monitoring system as described in any one of configurations 1 to 4, in which the measurement value of the turbidity meter does not be used when the measurement value of the turbidity meter exceeds a predetermined value or when the measurement value of the turbidity meter changes by more than a predetermined value within a predetermined time.

[0011] (Configuration 6) 6. A pollution load monitoring system according to any one of configurations 1 to 5, comprising an automatic Rr measurement device that automatically measures the oxygen utilization rate (Rr) of the mixed liquid in the aeration tank, the automatic Rr measurement device comprising: a sampling tank, an inflow means for inflowing the mixed liquid in the aeration tank into the sampling tank, an aeration means provided in the sampling tank, and a dissolved oxygen concentration meter provided in the sampling tank, the automatic Rr measurement device aerating the mixed liquid collected in the sampling tank using the aeration means, then stopping the aeration, measuring a DO value using the dissolved oxygen concentration meter, and measuring the oxygen utilization rate (Rr) based on the measured DO value.

[0012] (Configuration 7) 7. A pollution load monitoring system according to any one of configurations 1 to 6, comprising an automatic SV measuring device that automatically measures the activated sludge settling rate (SV) of the mixed liquid in the aeration tank, the automatic SV measuring device comprising: a sampling tank made of a transparent container; an inflow means for flowing the mixed liquid in the aeration tank into the sampling tank; and a camera for photographing the sampling tank, the automatic SV measuring device allowing the mixed liquid collected in the sampling tank to stand for a predetermined period of time, and then photographing the sampling tank containing the mixed liquid that has been left standing by the camera.

[0013] (Configuration 8) A method for determining pollution load in monitoring a wastewater treatment facility equipped with an aeration tank, comprising the steps of: acquiring in advance correlation information between turbidity information of aeration tank inflow water, which is inflow water to the aeration tank, and conductivity information of the aeration tank inflow water, and a BOD of the aeration tank inflow water; acquiring turbidity information and conductivity information of the aeration tank inflow water as needed, and calculating a BOD equivalent value based on the acquired turbidity information and conductivity information and the correlation information. Effect of the Invention

[0014] According to the pollution load monitoring system of the present invention, it is possible to automatically obtain and monitor the BOD equivalent value (pollution load information) of the inflow water flowing into the aeration tank. [Brief description of the drawings]

[0015] [Figure 1] FIG. 1 is a block diagram showing an outline of the configuration of a remote monitoring system for pollution load according to a first embodiment of the present invention. [Diagram 2] FIG. 1 is a diagram showing an outline of the configuration of an aeration tank inflow water monitoring tank according to the first embodiment. [Diagram 3] 1 is a flowchart showing an outline of the processing operation of the pollution load remote monitoring system of the first embodiment. [Figure 4] FIG. 1 is a block diagram showing an outline of the configuration of a pollution load remote monitoring system according to a second embodiment. [Diagram 5] FIG. 1 is a block diagram showing an outline of the configuration of an automatic Rr and SV measuring device according to a second embodiment. [Figure 6] A flowchart showing an outline of the processing operation of automatic Rr and SV measurement in the second embodiment. [Figure 7] Flowchart showing the outline of the processing operation of Rr automatic measurement [Figure 8] Flowchart showing the outline of the processing operation of SV automatic measurement [Figure 9] Rr, SV automatic measurement operation overview DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. Note that the following embodiment is one form for embodying the present invention, and is not intended to limit the scope of the present invention.

[0017] <Embodiment 1> FIG. 1 is a block diagram showing an outline of the configuration of a pollution load remote monitoring system (pollution load monitoring system) according to a first embodiment of the present invention. The pollution load remote monitoring system 1 of this embodiment is a remote monitoring system for acquiring pollution load information in a wastewater treatment facility 2 equipped with an aeration tank 25, and records (logs) the BOD conversion value, which is the pollution load information acquired automatically, and transmits (outputs) alarm information to an information processing device 4 via a network 3 if the BOD conversion value exceeds a predetermined value. Note that the BOD conversion value (mg / L) is an assumed value (estimated value) of BOD calculated by this system using a method described below. Similarly, the COD Cr The conversion value (mg / L) is the COD calculated by this system. Cr This is an assumed (estimated) value.

[0018] The wastewater treatment facility 2 to be monitored is, for example, a water treatment facility for treating wastewater from a food factory, etc. A raw water pump tank 21 into which raw water (factory wastewater to be treated) flows in; a flow rate adjusting tank 22 for adjusting the flow rate; A pretreatment device 23 for pressurized / normal pressure flotation, coagulation sedimentation, etc. an aeration tank 25 for performing biological treatment using an activated sludge method; A settling tank or membrane separation tank 26 for performing solid-liquid separation; A disinfection tank 27 for performing disinfection treatment; A discharge pump tank 28 for discharging the water; The wastewater treatment facility itself and the contents of the water treatment in the wastewater treatment facility are not the direct subject of the present invention, and any conventional wastewater treatment facility (a wastewater treatment facility equipped with an aeration tank) can be used (the configuration of the wastewater treatment facility is not limited to the configuration shown in FIG. 1), so a description of the wastewater treatment facility itself and the contents of the treatment in the wastewater treatment facility will be omitted here.

[0019] The pollution load remote monitoring system 1 of this embodiment is a remote monitoring system capable of automatically measuring (monitoring) the pollution load information (BOD equivalent value) of the inflow water into the aeration tank 25 almost in real time, i.e., capable of monitoring the load status of the aeration tank 25. The pollution load remote monitoring system 1 of this embodiment comprises an aeration tank inflow water monitoring tank 12 provided on the inflow path 24 of the aeration tank inflow water to the aeration tank 25, and a remote monitoring device 11 that performs calculation processing of the BOD conversion value, which is pollution load information, based on the sensor value of a sensor provided in the aeration tank inflow water monitoring tank 12.

[0020] FIG. 2 is a diagram showing an outline of the configuration of the aeration tank inflow water monitoring tank 12. As shown in FIG. The aeration tank inflow water monitoring tank 12 of this embodiment is as follows: an inflow water monitoring tank 121 provided on the inflow path 24 for the aeration tank inflow water, for sampling the aeration tank inflow water flowing into the aeration tank 25; A turbidity meter 122 is installed in the inflow water monitoring tank 121 to measure the turbidity of the inflow water to the aeration tank; A conductivity meter 123 is installed in the inflow water monitoring tank 121 to measure the conductivity of the inflow water to the aeration tank; It is equipped with: The turbidity meter 122 is a sensor that has a light emitting section and a light receiving section (not shown in particular) and irradiates light onto the aeration tank inflow water in the inflow water monitoring tank 121 and detects the transmitted light (or scattered light, etc.). It is used as a sensor that detects information regarding turbidity, that is, the cloudiness of the water caused by contaminants that are not dissolved in the water. Note that any sensor capable of measuring turbidity can be used as the turbidity meter. The conductivity meter 123 is a sensor that measures the conductivity of the water inflowing into the aeration tank in the inflow water monitoring tank 121, and is used as a sensor to detect contaminants dissolved in the water (the more contaminants dissolved (ionized) in the water, the higher the conductivity).

[0021] As shown in FIG. 1, the remote monitoring device 11 includes: An input / output terminal 112 to which the aeration tank inflow water monitoring tank 12 is connected; A storage unit 113 in which information and the like are stored, which will be described below, relating to "information on the correlation between the turbidity information of the aeration tank inflow water, the electrical conductivity information of the aeration tank inflow water, and the BOD of the aeration tank inflow water" and the like; an input / output unit 114 which is an input interface for a user (any input means such as an operation button, a keyboard, a touch panel, or a voice input unit) and an output interface (any output means such as a visual display device such as a display screen or an indicator, or an auditory output unit such as a speaker); A transmitting / receiving unit 115 for transmitting and receiving information to and from an information processing device 4 via a network 3; A control and calculation unit 111 that controls the device and performs calculation processing, etc. As will be described later, it has a function as "a calculation device that calculates a BOD equivalent value based on the measured values ​​of the turbidity meter and the conductivity meter." Note that the input / output terminal 112 is connected to the control / calculation unit 111 via an amplifier circuit, an A / D conversion circuit, a filter circuit, etc. (not shown) as appropriate to make it an appropriate signal to be input / output to / from the control / calculation unit 111. The remote monitoring device 11 can be configured by any information processing device, such as a microcomputer such as a PLC or MCU, or a PC, capable of executing the processes described below.

[0022] The network 3 may be any network such as the Internet or a local area network, and may be either wired or wireless (the transmitting / receiving unit 115 is appropriately used depending on the type of network, etc.). The information processing device 4 is an arbitrary device such as a PC or a mobile terminal owned by the manager of the wastewater treatment facility 2, for example.

[0023] In order for the remote monitoring device 11 to automatically measure (monitor) the pollution load information (BOD equivalent value) of the aeration tank inflow water almost in real time, the remote monitoring device 11 acquires and sets in advance "correlation information between the turbidity information of the aeration tank inflow water, the conductivity information of the aeration tank inflow water, and the BOD of the aeration tank inflow water." In this embodiment, the "correlation information between the turbidity information of the aeration tank inflow water and the conductivity information of the aeration tank inflow water and the BOD of the aeration tank inflow water" is 1. Turbidity meter and conductivity meter readings and COD Cr First correlation information which is correlation information between 2. COD Crand BOD, The first correlation information is made up of a first multiple regression equation and a second multiple regression equation.

[0024] The first correlation information is correlation information between the measurement values ​​of the turbidity meter and the conductivity meter and COD (Chemical Oxygen Demand, unit: mg / L), and is obtained and set by pre-sampling the aeration tank inflow water flowing into the aeration tank 25. More specifically, the inflow water to the aeration tank is sampled periodically and the turbidity, conductivity and COD of each sample are measured. Cr The actual measurements were taken, and turbidity and conductivity were used as explanatory variables, and COD Cr A multiple regression analysis is performed with the above as the objective variable to calculate correlation information (multiple regression equation). As an example (experiment), sampling was performed every 6 hours at a certain site to obtain a considerable amount of sample data, and multiple regression analysis was performed based on these sample data. Cr The COD calculated based on the multiple regression equation calculated above from the actual measured values ​​of turbidity and conductivity. Cr The error between the conversion value and COD is about -25% to +15%. Cr The results showed that the sign of the error was reversed (the trend changed) at a certain conversion value. Therefore, the point where the error sign is reversed (predetermined value) is used as the boundary to divide the multiple regression equations (COD Cr The first multiple regression equation is used when COD is less than a certain value, and the second multiple regression equation is used when COD is more than a certain value. Cr When the conversion value was calculated, COD Cr Actual measurements and COD Cr We were able to keep the error between the converted value and the actual value within the range of approximately ±10%. This tendency is based on the phenomenon that when an electrolyte is dissolved in pure water, the relationship between the concentration and the conductivity is proportional when the concentration is low, but the gradient becomes smaller as the concentration becomes high, and that when an electrolyte is dissolved in an aqueous solution of an organic compound, the gradient is large when the concentration of the organic compound is low, and the gradient is small when the concentration of the organic compound is high (based on these phenomena, COD Cr (The trend is thought to change with an increase in the converted value of .) Therefore, it is thought that the error can be reduced by using a multiple regression equation that, based on sampling at each site, separates cases as necessary (including cases that separate into two or more cases and cases that do not separate cases).

[0025] In addition, when the turbidity value in the sampling exceeded a predetermined value (specifically, 600 NTU in the above example), the data was not used and multiple regression analysis was performed. As mentioned above, a turbidimeter is a sensor that irradiates a sample with light and detects the transmitted light, so when a solid object passes in front of the light-emitting sensor or light-receiving sensor, blocking it, the turbidity (sensor value) may rise due to spike-like noise data. This type of spike-like noise data cannot be said to accurately reflect the turbidity, so it is processed to remove it. Note that, here, an example is given in which the turbidity (sensor value) is removed when it exceeds a predetermined value (or becomes equal to or greater than a predetermined value), but it is also possible to remove the turbidity (sensor value) when it changes by more than a predetermined value within a predetermined period of time (when it rises or falls rapidly like a spike).

[0026] The second correlation information is the COD Cr The BOD of the samples (one or several samples can be used) is measured and the ratio of these (conversion formula) is obtained.

[0027] The first correlation information and the second correlation information (parameters of each conversion formula) obtained as described above are input (set) by the user using the input / output unit 114 and stored in the storage unit 113. In addition, the COD used to distinguish between the first and second multiple regression formulas is Cr The value (predetermined value) is also set and stored as a threshold value.

[0028] Next, an overview of the processing operation of the remote monitoring device 11 will be described with reference to the flowchart in Fig. 3. Note that in the following description, the processing subject is omitted, but each process is executed by the control / calculation unit 111 by using information acquired from the storage unit 113 or the input / output terminal 112, etc. At a predetermined measurement timing (the measurement timing may be arbitrarily set, such as a preset measurement time or at preset time intervals), the sensor values ​​of the turbidity meter 122 and the conductivity meter 123 are read to obtain the turbidity and conductivity of the inflow water to the aeration tank (step 301). At this time, if the turbidity exceeds a predetermined value, the turbidity measurement is redone (step 302). As with the above-described sampling, the purpose is to remove spike-like noise data ("if the measurement value of the turbidity meter exceeds a predetermined value or if the measurement value of the turbidity meter changes by more than a predetermined value within a predetermined time, the measurement value is not used"). When the turbidity measurement is redone, the conductivity may also be measured again, or the conductivity may not be measured again.

[0029] After the turbidity and conductivity of the aeration tank inflow water are obtained, a COD equivalent value is calculated from these using the first multiple regression equation (first correlation information) (step 303). If the COD conversion value is equal to or greater than the threshold value, the second multiple regression equation (first correlation information) is used to recalculate the COD conversion value (step 304: Yes→step 305). In the next step 306, the COD equivalent value calculated by the first multiple regression equation (step 303) or the second multiple regression equation (step 305) is converted into a BOD equivalent value (the BOD equivalent value is calculated using the second correlation information), and this is logged (stored in the memory unit 113).

[0030] If the calculated BOD conversion value is greater than or exceeds a predetermined value (a value set in advance depending on the equipment conditions and operating conditions of each site), an alert (warning information) is sent to the information processing device 4 via the network 3 (step 307: Yes → step 308).

[0031] In the next step 309, the process waits for the next measurement timing (as described above, the measurement timing may be arbitrarily set, such as a preset measurement time or measurements at preset time intervals), and when the next measurement timing arrives, the process returns to step 301 and the above process is repeated. By the above process, the turbidity information and conductivity information of the inflow water to the aeration tank are acquired at any time, and the BOD equivalent value is calculated and stored based on the turbidity information and the correlation information. Therefore, the BOD equivalent value (pollutant load information) of the inflow water flowing into the aeration tank can be automatically acquired (and logged) in almost real time.

[0032] As described above, according to the pollution load remote monitoring system 1 of this embodiment, the BOD equivalent value (pollution load information) of the inflow water flowing into the aeration tank can be automatically acquired (and logged) almost in real time, and this can be monitored remotely. Conventionally, BOD was measured by controlling the temperature of sample water in a thermostatic chamber for a certain period (5 days for BOD5) and measuring the amount of oxygen consumed. Therefore, it was basically measured by an analysis laboratory, and it was difficult to measure on-site in real time, and for example, it was difficult to capture fluctuations from hour to hour. However, the remote pollution load monitoring system 1 of this embodiment makes this possible. By making it possible to measure in real time, even if the load changes suddenly, it is possible to respond immediately to this (such as optimizing the operating conditions), which is very useful. In addition, since the load status can be continuously logged, it is possible to grasp trends (such as seasonal trends) by analyzing the data and take advance measures according to predicted changes in the load status based on the trends.

[0033] In this embodiment, the information processing device 4 is described only as receiving an alert when the BOD conversion value reaches or exceeds a predetermined value (i.e., the load becomes large). However, it is of course also possible to have the information processing device 4 access the remote monitoring device 11 and refer to logged BOD conversion values ​​or real-time BOD conversion values, etc.

[0034] In this embodiment, the correlation information between the turbidity information of the inflow to the aeration tank, the conductivity information of the inflow to the aeration tank, and the BOD of the inflow to the aeration tank is "1. The measurement values ​​of the turbidity meter and the conductivity meter and the COD Cr "1. Correlation Information" which is correlation information between "COD Cr and BOD" and "second correlation information which is correlation information between BOD and the first correlation information", but the present invention is not limited to this. For example, in sampling, the turbidity, conductivity, and BOD of each sample may be measured, and a multiple regression analysis may be performed with the turbidity and conductivity as explanatory variables and the BOD as a target variable, so that the BOD equivalent value can be calculated directly from the turbidity and conductivity. However, since it is necessary to measure the BOD of multiple samples at the time of sampling, and the samples must be temperature-controlled in a thermostatic chamber for 5 days for BOD5, it is very time-consuming to obtain the correlation information (a considerable number of samples). In contrast, according to the two-stage method of the embodiment, the BOD measurement is only required once or for a few samples, so the work of obtaining the correlation information is made more efficient. The "correlation information between the turbidity information of the aeration tank inflow water and the conductivity information of the aeration tank inflow water, and the BOD of the aeration tank inflow water" may be updated as necessary. For example, when the production situation in a factory changes, the correlation information may be updated based on sampling of the wastewater (aeration tank inflow water) after the change. In addition, the BOD of the aeration tank inflow water may be measured periodically, and the error with the BOD conversion value may be checked, and if the error is large, the correlation information may be updated (sampled).

[0035] In this embodiment, the COD is CrHowever, the present invention is not limited to this. For example, COD may be Mn The above formula may be used. Furthermore, in the embodiment, the BOD equivalent value is logged as an example, but it goes without saying that the COD equivalent value may also be logged.

[0036] In this embodiment, an alert (warning information) is sent (warning information is output) to the information processing device 4 when the BOD conversion value (pollution load information) is equal to or greater than a predetermined value, but in addition to a simple alert, instructions to change the recommended operating conditions (for example, specific indication of the valve operation amount for reducing the inflow amount so that the load on the aeration tank does not become too high) may also be given. In addition, the output of the warning information is not limited to being sent to the information processing device 4, and may be, for example, a warning output in a device installed in the wastewater treatment facility 2.

[0037] <Embodiment 2> Fig. 4 is a block diagram showing an outline of the configuration of a pollution load remote monitoring system of embodiment 2. The same reference numerals as in embodiment 1 (Fig. 1) are used for components having the same configuration as in embodiment 1, and the description here will be simplified or omitted.

[0038] The pollution load remote monitoring system 1' of this embodiment has the same configuration and functions as the pollution load remote monitoring system 1 of embodiment 1, and further has an Rr, SV automatic measuring device 13, thereby having the function of automatically measuring the oxygen utilization rate (Rr) and activated sludge settling rate (SV) of the aeration tank mixed liquid (hereinafter simply referred to as the "mixed liquid"), which is a mixed liquid of activated sludge and raw water in the aeration tank 25.

[0039] FIG. 5 is a block diagram showing an outline of the configuration of the Rr, SV automatic measuring device 13. As shown in FIG. The Rr, SV automatic measuring device 13 is A sampling tank 131 made of a transparent container; An inflow means 132 for inflowing the mixed liquid in the aeration tank 25 into the sampling tank 131; an aeration means (aeration nozzle 1331 and blower 1332) provided in the sampling tank 131 for supplying oxygen to the mixed liquid in the sampling tank 131; a dissolved oxygen concentration meter 134 provided in the sampling tank 131 for measuring the dissolved oxygen concentration of the mixed liquid in the sampling tank 131; A camera 135 for photographing the sampling tank 131; A water level gauge 136 for measuring the water level in the sampling tank 131; A circulation path 137 for circulating the water in the sampling tank 131; A cleaning means 138 for injecting cleaning water into the sampling tank 131; A drainage path 139 for draining water from the sampling tank 131; It is equipped with:

[0040] The inflow means 132 has an upstream collection path 1321 for collecting the mixed liquid from the inflow side of the aeration tank 25 , a downstream collection path 1322 for collecting the mixed liquid from the outflow side of the aeration tank 25 , and a pump 1323 . Each path is provided with an electric valve (indicated as MV in the figure) for opening and closing the path. Each motor-operated valve, pump 1323, blower 1332, and camera 135 are connected so as to be controllable by the control and calculation unit 111 of the remote monitoring device 11. In addition, they are connected so that the measurement values ​​of a water level gauge 136 and a dissolved oxygen concentration meter 134 can be acquired by the control and calculation unit 111.

[0041] Next, an outline of the process for automatically measuring the oxygen utilization rate (Rr) and activated sludge settling rate (SV) of the mixed liquor in the aeration tank 25 will be described with reference to the flowcharts of Figures 6 to 8. Note that, although the main processing entity is omitted in the following description, each process is executed by the control and calculation unit 111 as in the first embodiment.

[0042] FIG. 6 is a flow chart showing an outline of the entire process of automatic measurement of Rr and SV. The loop process of steps 601 and 602 is a process of waiting for the arrival of the measurement timing of each of Rr and SV. The measurement timing of each of them may be arbitrarily set, such as a preset measurement time or a measurement at a preset time interval. When it is time to measure Rr (step 601: Yes), the process proceeds to step 603 to perform the Rr measurement process (described below), and the obtained Rr data is recorded (logged) and transmitted to the information processing device 4 via the network 3 (step 604). When it is time to measure SV (step 602: Yes), the process proceeds to step 605 where SV measurement processing (described below) is performed, and the obtained SV data is recorded (logged) and transmitted to the information processing device 4 via the network 3 (step 606).

[0043] FIG. 7 is a flow chart showing an outline of the processing operation of the Rr automatic measurement executed in step 603 of FIG. First, a predetermined amount of the mixed liquid in the aeration tank 25 is made to flow into the sampling tank 131 (step 701). This process is performed by opening either the motor valve on the upstream collection path 1321 (an electromagnetic valve or other mechanism that can be substituted as long as it can switch routes) or the motor valve on the downstream collection path 1322, while closing the motor valves on the circulation path 137 and the discharge path 139, and driving the pump 1323 until the water level obtained by the water level gauge 136 reaches a predetermined value. The reason why the mixed liquid can be collected from both the inflow side and the outflow side of the aeration tank 25 is that the raw water load is evaluated by measuring Rr on the inflow side (upstream side), and the treatment failure of the biological treatment is detected by measuring Rr on the outflow side (downstream side). That is, a process is performed in which either the motor valve on the upstream collection path 1321 or the motor valve on the downstream collection path 1322 is opened depending on each purpose. Once a predetermined amount of mixed liquid has been collected, the blower 1332 is driven to aerate the mixed liquid, and aeration is continued until the measurement value (DO value) taken by the dissolved oxygen concentration meter 134 reaches a predetermined value 1 (e.g., 5 mg / L) (i.e., the mixed liquid in the sampling tank 131 is brought to a predetermined dissolved oxygen concentration), and when the predetermined value 1 is reached, the blower 1332 is stopped to stop the aeration (steps 702 to 704). When the mixed liquid in the sampling tank 131 has a predetermined dissolved oxygen concentration, the dissolved oxygen concentration of the mixed liquid in the sampling tank 131 is measured at predetermined intervals while stirring the mixed liquid, and when the dissolved oxygen concentration becomes equal to or less than a predetermined value 2 (for example, 1 mg / L), Rr is calculated based on the time it took for the dissolved oxygen concentration to change from predetermined value 1 to 2 and the values ​​of predetermined values ​​1 and 2 (steps 705 to 707). Note that "stirring the mixed liquid" is performed by closing the motor-operated valves of the upstream collection path 1321, downstream collection path 1322, and discharge path 139, opening the motor-operated valve of the circulation path 137, and driving the pump 1323. After the measurement of Rr is completed, the sampling tank 131 is drained and cleaned (step 708) to terminate the Rr measurement process. The sampling tank 131 is drained by opening the motor-operated valve of the discharge path 139, and cleaning is performed by opening the motor-operated valve on the cleaning means 138 to allow cleaning water to flow into the sampling tank 131 (and then discharge it). The cleaning process may involve storing a predetermined amount of cleaning water in the sampling tank 131 and then draining it multiple times (when storing a predetermined amount of cleaning water, the cleaning water may be circulated through the circulation path 137, etc.).

[0044] FIG. 8 is a flow chart showing an outline of the processing operation of the automatic SV measurement executed in step 605 of FIG. First, a predetermined amount of the mixed liquid in the aeration tank 25 is made to flow into the sampling tank 131 (step 801). Basically, this is the same processing concept as step 701 in Fig. 7, but here, the mixed liquid from the aeration tank 25 is sampled using only the downstream sampling path 1322. Once a predetermined amount of the mixed liquid has been collected, it is left to stand for a predetermined period of time (for example, 30 minutes) (step 802). After leaving the mixture to stand for a predetermined time, the sampling tank containing the left mixed liquid is photographed by the camera 135 (step 803). As shown in the conceptual diagram of FIG. 9(b), due to the precipitation of activated sludge, an interface appears in the mixed liquid in the sampling tank, and photographing this interface can be used as information indicating the SV. Note that the sampling tank may be provided with a scale indicating a ratio according to the amount of the mixed liquid to be collected, and the camera 135 may be configured to photograph this scale, thereby making the information indicating the SV easier to understand. In addition to simply photographing the mixture, the position of the interface may be automatically determined by image recognition of the photographed image data, and the ratio of the position of the interface to the collected mixed liquid (i.e., the SV itself) may be automatically calculated. After the camera captures the image (obtaining information indicating SV), the sampling tank 131 is drained and cleaned (step 804) to terminate the Rr measurement process. The drainage and cleaning process of the sampling tank 131 is similar in concept to step 708 in FIG.

[0045] As described above, according to the pollution load remote monitoring system 1' of this embodiment, the oxygen utilization rate (Rr) and activated sludge settling rate (SV) of the mixed liquor in the aeration tank can be automatically acquired (and logged) almost in real time, and these can be monitored remotely. In this embodiment, the information processing device 4 is described only as receiving information (Rr, SV), but it is of course also possible to have the information processing device 4 access the remote monitoring device 11 and refer to the logged information indicating Rr and SV.

[0046] In this embodiment, the Rr, SV automatic measuring device 13 is an apparatus that measures both Rr and SV, but the present invention is not limited to this. For example, a measuring device for Rr and a measuring device for SV may be provided separately. FIG. 9 shows an example in which a measuring device for Rr and a measuring device for SV are separate (the same reference numerals are used for the same components as in the Rr, SV automatic measuring device 13 (FIG. 5)). 9(a) includes a sampling tank 131, inflow means 132, aeration means (aeration nozzle 1331 and blower 1332), a dissolved oxygen concentration meter 134, a water level gauge 136, a circulation path 137, cleaning means 138, and a discharge path 139. The sampling tank in the Rr automatic measurement device 13' does not need to be a transparent container. The SV automatic measuring device 13 ″ of FIG. 9( b ) includes a sampling tank 131 , an inflow means 132 , a camera 135 , a water level gauge 136 , a cleaning means 138 , and a discharge path 139 .

[0047] In this embodiment, the process of automatically measuring the oxygen utilization rate (Rr) and activated sludge settling rate (SV) of the mixed liquor in the aeration tank 25 is executed by the control and calculation unit 111 of the remote monitoring device, but the present invention is not limited to this. The process of automatically measuring Rr or the process of automatically measuring SV may be executed in the automatic Rr measuring device or the automatic SV measuring device by providing a control unit or the like in the automatic Rr measuring device or the automatic SV measuring device.

[0048] In each embodiment (FIGS. 1 and 4), the remote monitoring device 11 is depicted as being located at the site of the wastewater treatment facility 2, and therefore, the "process of calculating the BOD equivalent value based on the measurement values ​​of the turbidity meter and the conductivity meter" is depicted as being performed at the site of the wastewater treatment facility 2, but the present invention is not limited to this. For example, the "process of calculating the BOD conversion value based on the measurement values ​​of the turbidity meter and the conductivity meter" may be executed on a server on the Internet 3 (cloud) (in this case, the server will have the function of a "calculation device that calculates the BOD conversion value based on the measurement values ​​of the turbidity meter and the conductivity meter"), etc. In addition, the process of calculating the BOD conversion value may be performed locally, and this calculated BOD conversion value may then be logged on a server on the Internet 3 (cloud), and the server may be accessed from the information processing device 4 to obtain the information. The same is true for the process of automatically measuring Rr and the process of automatically measuring SV; these processes may be executed by a server on the Internet 3 (cloud) that receives the measurement values ​​acquired at the sites (of course, operations that require physical on-site operations are executed at each site), or the data may be stored on a server on the Internet 3 (cloud), etc. In addition, the "pollutant load monitoring system capable of automatically acquiring and monitoring the BOD equivalent value (pollutant load information) of inflow water flowing into an aeration tank" according to the present invention does not need to be a remote monitoring system via the Internet, etc., but may be a system constructed locally on-site. As with the Rr automatic measuring device or the SV automatic measuring device, it does not need to be a remote monitoring system via the Internet, etc., but may be a system constructed locally on-site. [Explanation of symbols]

[0049] 1. Pollution load remote monitoring system (Pollution load monitoring system) 11...Remote monitoring device (computing device) 12...Aeration tank inflow water monitoring tank 122...turbidity meter 123...Conductivity meter 13...Rr, SV automatic measuring device 131...Sampling tank 132...Inflow means 1331...Aeration nozzle (aeration means) 1332...Blower (aeration means) 134... Dissolved oxygen concentration meter 135...Camera 2. Wastewater treatment facilities 25...Aeration tank 3...Network 4. Information processing equipment

Claims

1. A monitoring system for acquiring pollution load information in a wastewater treatment facility equipped with an aeration tank, A turbidity meter for measuring the turbidity of the aeration tank inflow water, which is the inflow water to the aeration tank; a conductivity meter for measuring the conductivity of the aeration tank inflow water; A calculation device that calculates a BOD equivalent value based on the measurements of the turbidity meter and the conductivity meter; A pollution load monitoring system comprising:

2. 2. The pollution load monitoring system according to claim 1, wherein, when the BOD converted value exceeds a predetermined value, alarm information is output.

3. First correlation information, which is correlation information between the measurement values ​​of the turbidity meter and the conductivity meter and COD, and second correlation information, which is correlation information between COD and BOD, are set in advance, calculating a COD equivalent value using the first correlation information based on the measured values ​​of the turbidity meter and the conductivity meter; The pollution load monitoring system according to claim 1 , further comprising: a step of calculating the BOD equivalent value based on the COD equivalent value by using the second correlation information.

4. the first correlation information is a multiple regression equation, the multiple regression equation having a first multiple regression equation and a second multiple regression equation; 4. The pollution load monitoring system according to claim 3, wherein, when the COD equivalent value calculated using the first multiple regression equation based on the measurement values ​​of the turbidity meter and the conductivity meter is equal to or greater than a threshold value, the COD equivalent value is recalculated using the second multiple regression equation based on the measurement values ​​of the turbidity meter and the conductivity meter.

5. 2. The pollution load monitoring system of claim 1, wherein the measurement value of the turbidity meter is not used when the measurement value of the turbidity meter exceeds a predetermined value or when the measurement value of the turbidity meter changes by more than a predetermined value within a predetermined time.

6. An automatic oxygen utilization rate (Rr) measuring device for automatically measuring the oxygen utilization rate (Rr) of the mixed liquid in the aeration tank, A sampling tank; an inflow means for inflowing the mixed liquid in the aeration tank into the sampling tank; an aeration means provided in the sampling tank; a dissolved oxygen concentration meter provided in the sampling tank; Equipped with 6. The pollution load monitoring system according to claim 1, further comprising an automatic Rr measurement device that aers the mixed liquid collected in the sampling tank using the aeration means, stops the aeration, measures a DO value using the dissolved oxygen concentration meter, and measures an oxygen utilization rate (Rr) based on the measured DO value.

7. An automatic SV measuring device for automatically measuring the activated sludge settling rate (SV) of the mixed liquid in the aeration tank, A sampling tank made of a transparent container; an inflow means for inflowing the mixed liquid in the aeration tank into the sampling tank; A camera for photographing the sampling tank; Equipped with 6. The pollution load monitoring system according to claim 1, further comprising an automatic SV measuring device that photographs the sampling tank containing the mixed liquid that has been left standing in the sampling tank for a predetermined period of time using the camera after the mixed liquid has been left standing in the sampling tank.

Images