WO2013136503A1

WO2013136503A1 - System for operating water treatment plant and method for planning amount of water supply

Info

Publication number: WO2013136503A1
Application number: PCT/JP2012/056829
Authority: WO
Inventors: 信補高橋; 進吾足立; 真宮田
Original assignee: 株式会社日立製作所
Priority date: 2012-03-16
Filing date: 2012-03-16
Publication date: 2013-09-19

Abstract

[Problem] A system for operating a water treatment plant that supplies recycled water to satisfy demand and reduces the treatment cost of the water recycling treatment for producing the recycled water. [Solution] The system (20) for operating a water treatment plant, which manages a water treatment plant (10) that performs sewage treatment on sewage (1) to generate treated water (2) and performs water recycling treatment on the treated water (2) to produce recycled water (3), is provided with: a treated water quality-predicting unit (211) that predicts the water quality of the treated water (2) generated by the sewage treatment; a recycled water demand-predicting unit (212) that predicts the demand for recycled water; and a plan problem-solving unit (213) that calculates a planned value using specified calculations on the basis of the predicted water quality value for the treated water (2) predicted by the treated water quality-predicting unit and controls the volume of treated water (2) on which water recycling treatment is performed at the water treatment plant (10) according to said planed value. The system is characterized in that the planned value calculated at this time is such that the volume of recycled water (3) produced from the treated water (2) by the water recycling treatment according to the planned value satisfies the predicted demand.

Description

Water treatment plant operation system and water volume planning method

The present invention relates to a water treatment plant operation system and a water supply amount planning method, and more particularly to a water treatment plant operation system and a water supply amount planning method for managing a water treatment plant that purifies sewage and produces reclaimed water that can be reused. And suitable.

In order to effectively use water resources, it has been promoted to recycle and reuse water once used, such as domestic wastewater or industrial wastewater. Reclaimed water is used in various applications such as industrial water, cooling water, toilet water, water for spraying, and water for landscapes.

Patent Document 1 discloses a water treatment plant that efficiently produces reclaimed water having a plurality of uses. In the water treatment plant disclosed in Patent Document 1, water demand and sewage inflow by use are predicted and distributed to a plurality of independent water treatment systems according to a distribution pattern based on the prediction result. And the water treatment plant disclosed by patent document 1 produces | generates and supplies the treated water according to the water quantity and water quality of a demand destination by mixing the treated water processed by each processing system.

JP 2006-281159 A

By the way, the water treatment plant described in Patent Document 1 has a plurality of water treatment systems having different treatment performances in order to produce reclaimed water for various uses, and sewage purification treatment is performed in each water treatment system. Is called. For example, in Patent Document 1, a water treatment system that performs ozone treatment for deodorizing, decolorizing, and decomposing organic matter after deodorizing, decolorizing, and decomposing organic matter by removing microorganisms, sewage, and other activated sludge treatment using microorganisms in sewage. Is illustrated.

However, in the water treatment plant described in Patent Document 1, any predetermined purification treatment is performed on all inflowing sewage. When the amount of supplied water exceeds the amount of demand water, water that is discharged into the river without being distributed to the demand is generated. However, in the water treatment plant described in Patent Document 1, such extra water is used. However, unnecessary purification treatment is performed, and there is a problem that the cost of water regeneration treatment increases.

Moreover, although the inflow amount of the sewage to a water treatment plant changes with dates, in the water treatment plant described in patent document 1, since purification processing is performed to all the inflowing sewage, inefficient purification processing May be performed. For example, when the amount of inflow of sewage is large, the number of sewage removal targets increases, so the quality of treated water by activated sludge treatment decreases. Even in such a case, in order to realize a predetermined water quality, a large amount of treated water with low water quality must be ozone-treated, which is inefficient in terms of cost and processing time.

The present invention has been made in consideration of the above points, and is a water treatment plant capable of supplying reclaimed water that satisfies the demand and reducing the treatment cost for water reclaim treatment for producing reclaimed water. It intends to propose an operation system and a water supply planning method.

In order to solve such a problem, in the present invention, a water treatment plant operation system for managing a water treatment plant that produces sewage by performing sewage treatment on the sewage, and performing water regeneration treatment on the treated water to produce the reclaimed water. In, the treated water quality prediction unit for predicting the quality of the treated water generated by the sewage treatment, the reclaimed water demand prediction unit for predicting the demand amount of the reclaimed water, and the treatment predicted by the treated water quality prediction unit A plan problem solving unit that calculates a plan value by a predetermined calculation based on a water quality prediction value of water, and controls the amount of treated water subjected to water regeneration treatment in the water treatment plant according to the plan value, The plan value calculated by the plan problem solving unit is calculated based on the amount of reclaimed water produced from the treated water according to the plan value by the water regeneration process. Water treatment plant operation system which satisfies the measurement has been forecast value is provided.

Moreover, in order to solve such a problem, in the present invention, in the water treatment plant for producing sewage by performing sewage treatment on sewage, and generating the sewage by subjecting the sewage to water regeneration, In the water supply amount planning method for planning the amount of treated water to be applied, a demand amount predicting step for predicting the demand amount of the reclaimed water, and a treated water quality prediction for predicting the quality of the treated water generated by the sewage treatment A plan value calculating step for calculating a planned value by a predetermined calculation based on the predicted predicted water quality value of the treated water, and performing a water regeneration process in the water treatment plant according to the calculated planned value A water supply amount control step for controlling the amount of treated water, and the plan value calculated in the plan value calculation step is changed from treated water according to the plan value to the water regeneration treatment. The amount of recycled water to be produced What is water planning method that satisfies the predicted demand forecast value by the demand prediction step is provided.

According to the present invention, it is possible to supply reclaimed water that satisfies the demand and to reduce the processing cost for water reclaim processing for producing reclaimed water.

It is a block diagram which shows the whole structure of the water treatment plant operation system by 1st Embodiment. It is a flowchart which shows the process procedure in which the water treatment plant operation system shown in FIG. 1 determines the operation plan of a water supply amount. It is the graph which showed each inflow amount and water quality about the sewage and the treated water in time series. It is the table which summarized the density | concentration of the various water quality components in the treated water in which the sewage treatment was performed in time series. It is a block diagram which shows the whole structure of the water treatment plant operation system by 2nd Embodiment. It is a flowchart which shows the process procedure in which the water treatment plant operation system shown in FIG. 5 determines the operation plan of a water supply amount. It is the schematic explaining the dynamic model which calculates the water quality prediction value of a treated water. It is a table which shows an example of the parameter of the dynamic model shown in FIG. It is a block diagram which shows the whole structure of the water treatment plant operation system by 3rd Embodiment. It is a flowchart which shows the process procedure which the water treatment plant operation system shown in FIG. 9 calculates the table data of a water quality calculation model. It is a graph which shows an example of each measured value of the inflow of sewage, the quality of sewage, and the quality of treated water.

(1) First Embodiment (1-1) Configuration According to this Embodiment In FIG. 1, reference numeral 20 denotes a water treatment plant operation system according to the first embodiment as a whole. The water treatment plant operation system 20 manages the distribution of treated water in the water treatment plant 10.

First, the water treatment plant 10 will be described. The water treatment plant 10 is a plant for producing reclaimed water by performing sewage treatment and water regeneration treatment on the sewage 1, and includes a first sedimentation tank 11, an activated sludge treatment tank 12, a final sedimentation tank 13, and distribution of treated water. A device 14, a water regeneration treatment device 15, a distribution reservoir 16, and a flocculant storage tank 17 are provided. The water treatment plant 10 is provided with a plurality of pumps. Below, the purification process performed with respect to the sewage 1 between the first sedimentation basin 11 and the final sedimentation basin 13 is called a sewage treatment, and the water after a sewage treatment is called the treated water 2. Furthermore, the purification process performed on the treated water 2 by the water regeneration treatment device 15 is referred to as a water regeneration process, and the water after the water regeneration process is referred to as a reclaimed water 3.

Here, a series of water treatment in the water treatment plant 10 will be described. In the water treatment plant 10, first, sewage 1 composed of domestic wastewater or industrial wastewater flows into the settling basin 11 first. First, the sedimentation tank 11 removes the solid content of the inflowing sewage by precipitation. Next, the supernatant liquid of the sewage that first flows into the settling basin 11 flows into the activated sludge treatment tank 12.

In the activated sludge treatment tank 12, a blower 21 which is a blower for supplying oxygen into the tank, a pump 22 for circulating the sewage 1 flowing into the tank, and a flocculant storage tank 17 flocculates in the activated sludge treatment tank 12. A pump 25 for injecting the agent is provided. In the activated sludge treatment tank 12, oxygen is supplied from the blower 21 to the microorganisms in the activated sludge treatment tank 12 to induce explosive growth and proliferation of microorganisms, and organic pollution of the sewage 1 is reduced by metabolism of the microorganisms. Activated sludge treatment is performed. Further, the flocculant injected from the flocculant reservoir 17 is used to collect particles dispersed in water and promote sedimentation, and has an effect of removing the turbidity of the sewage 1. Then, the water subjected to the activated sludge treatment in the activated sludge treatment tank 12 flows into the final sedimentation tank 13.

The final sedimentation basin 13 includes a pump 23 for returning a part of the precipitated sludge to the activated sludge treatment tank 12 and a pump 24 for discharging another part of the precipitated sludge as excess sludge to the outside of the water treatment plant 10. Is provided. In the final sedimentation basin 13, the solid content of the inflowed water is removed by precipitation, and the supernatant is discharged as treated water 2 to the treated water distribution device 14. A part of the solid content precipitated in the final sedimentation tank 13 is returned to the activated sludge treatment tank 12 by the pump 23 and used for activated sludge treatment.

The treated water distribution device 14 has a mechanism for feeding the treated water 2 and is realized by, for example, a valve, a pump, a weir, or the like. The treated water distribution device 14 discharges a part of the treated water 2 to the water regeneration treatment device 15 and discharges the others to the river according to the instruction of the water treatment plant operation system 20.

In the water regeneration treatment device 15, the water regeneration treatment is performed on the treated water 2 in order to further remove various components contained in the treated water 2. In the water regeneration treatment apparatus 15, for example, sand filtration, biofilm filtration, activated carbon adsorption, filtration through a microfiltration membrane (MF membrane: Microfiltration Membrane), filtration through a reverse osmosis membrane (RO membrane: Reverse Osmosis Membrane), or ozone treatment At least one of the water regeneration processes is performed. For these water regeneration treatment methods, commonly used methods can be used.

The treated water that has been subjected to water regeneration treatment in the water regeneration treatment device 15 is stored in the reservoir 16 as reclaimed water. Thereafter, the reclaimed water stored in the distributing reservoir 16 is discharged by the pump 25 and distributed to consumers.

Next, the configuration of the water treatment plant operation system 20 will be described. The water treatment plant operation system 20 includes a control device 210, a database 220 that provides storage data to the control device 210, and an input unit 230 that transmits an input signal to the control device 210.

For example, the control device 210 controls each part in the control device 210 by executing a program and gives a water supply instruction to the treated water distribution device 14 (Central Processing Unit) (not shown), and the CPU executes the program This is realized by a computer having a memory (not shown) in which a program is loaded and used, and a storage device (not shown) for storing various data and programs.

The control device 210 has a treated water quality prediction unit 211, a reclaimed water demand prediction unit 212, and a planning problem solving unit 213 as its functional configuration.

The treated water quality predicting unit 211 determines the water quality of the treated water 2 at each time of a predetermined time after the present (for example, from 0:00 to 24:00) based on past performance data on the water quality of the treated water 2. Predict what will happen.

The reclaimed water demand prediction unit 212 predicts how much reclaimed water is demanded at a certain time after the present (for example, from 0:00 to 24:00) based on past performance data.

The planning problem solving unit 213 controls the amount of water supplied to the water regeneration treatment device 15 by the treated water distribution device 14. The planning problem solving unit 213 solves a predetermined planning problem (details will be described later) based on the predicted values calculated by the treated water quality prediction unit 211 and the reclaimed water demand prediction unit 212, and the treated water distribution device 14 according to the solution. Instruct the amount of water to be sent.

The database 220 is a storage device, and stores time-series data related to the concentration of water quality components of the treated water 2 and time-series data related to the demand for reclaimed water based on past performance data in the water treatment plant 10. The various water quality components correspond to, for example, biochemical oxygen demand (BOD) indicating the amount of organic matter in water, phosphorus, nitrogen, suspended solids (SS), and the like. Details of the data stored in the database 220 will be described later with reference to FIG.

The input unit 230 is an input device in which an input operation and data input from a user are performed, and an input signal corresponding to the input content is transmitted to the control device 210.

(1-2) Processing according to the present embodiment Hereinafter, a processing procedure in which the water treatment plant operation system 20 plans a water supply amount in the water treatment plant 10 will be described with reference to FIG.

First, in step S101, a water quality component that is particularly desired to be removed is selected from among the water quality component items by a user input operation on the input unit 230. Each item of the water quality component is, for example, BOD, total nitrogen (TN), total phosphorus (TP), or solid suspended matter (SS). At this time, a predetermined screen may be displayed on a display unit (not shown) to allow the user to select a removal item.

Next, in step S102, the treated water quality prediction unit 211 reads time-series data relating to the concentration of the water quality component of the treated water 2 from the database 220.

(1-2-1) Time Series Data on the Concentration of Water Quality Components of Sewage Here, the time series data on the concentration of the quality components of the treated water 2 stored in the database 220 will be described in detail.

FIG. 3 shows (a) the amount of sewage 1 inflow, (b) the quality of sewage 1 (BOD concentration), (c) the amount of effluent of treated water 2 and (d) the quality of effluent 2 (BOD concentration). It is an example of the change by the elapsed time of 24 hours. Moreover, FIG. 4 illustrates the concentration of a plurality of components for the water quality of the treated water 2 at each time of the day. The table 91 includes a time column 91A in which each time is described, a BOD concentration column 91B, a TN concentration column 91C, a TP concentration column 91D, and an SS concentration column 91E in which the concentration of each water component is described. Yes. FIG. 3D shows the BOD concentration of the treated water 2, but it can be seen from FIG. 4 that other water quality components (TN concentration, TP concentration, and SS concentration) also vary with time.

Here, most of the water quality components in the sewage 1 are removed by the treatment in the activated sludge treatment tank 12 and the final sedimentation basin 13 as shown in FIGS. 3B and 3D, but all are removed. However, several percent to several tens of percent remain even at the stage of the treated water 2.

In addition, as shown in FIGS. 3A and 3D, even when the quality of the sewage 1 is stable, it is understood that the quality of the treated water 2 varies due to the variation of the inflow amount of the sewage 1. . Generally, after a while after the inflow of the sewage 1 increases, the water quality of the treated water 2 decreases (component concentration increases). At this time, the timing at which the water quality of the treated water 2 decreases can be approximated by the relationship of “dead time + m-order delay system (m = 1, 2,...)” With respect to the timing at which the inflow amount of the sewage 1 increases. it can. That is, the water quality of the treated water 2 is a value that is linked to the inflow amount of the sewage 1 and the water quality.

Furthermore, since the inflow amount and the water quality of the sewage 1 show different values depending on the season, day of the week, and time, etc., it can be considered as a time-variable value using these season, day of the week, and time as parameters. As described above, since the quality of the treated water 2 is linked to the inflow amount and the quality of the sewage 1, the quality of the treated water 2 is also a time-variable value with parameters such as season, day of the week, and time. Can be considered.

Therefore, the treated water quality prediction unit 211 classifies the past performance data regarding the quality of the treated water 2 in advance according to the season, day of the week, and time. The treated water quality prediction unit 211 obtains the concentration of the water quality component of the treated water 2 in units of season, day of the week, and time by taking the average value of the classification data in the same parameter, and thus the water quality component Time series data relating to the concentration of the water quality components collected for each time is stored in the database 220. For example, since the table 91 in FIG. 4 is a table showing data for one day, a total of 28 such tables 91 are created for each season (4 patterns) and days of the week (7 patterns) in the database 220. And stored in the database 220.

The treated water quality prediction unit 211 then selects the treated water 2 based on the time series data corresponding to the current season and day of the week among the time series data related to the concentration of the water quality components of the treated water 2 read from the database 220. Predicted values for 24 hours after the present of each water quality (BOD concentration, TN concentration, TP concentration, and SS concentration) are calculated as time series data for 24 hours.

Next, in step S103, the reclaimed water demand prediction unit 212 reads time-series data regarding the reclaimed water demand from the database 220.

(1-2-2) Time-series data related to the demand for reclaimed water Here, the time-series data related to the demand for reclaimed water will be briefly described. The demand value of the reclaimed water is considered to be a time-variable value having parameters such as season, day of the week, or time as well as the inflow amount and quality of the sewage 1. Therefore, the reclaimed water demand prediction unit 212 classifies the past performance data regarding the reclaimed water demand in advance according to the season, day of the week, and time, and is similar to the time-series data regarding the concentration of the water quality component of the treated water 2 described in step S102. Processing is performed, and time series data relating to the demand for reclaimed water is stored in the database 220.

Then, the reclaimed water demand forecasting unit 212 is based on the time series data corresponding to the current season and day of the week in the time series data related to the demand for reclaimed water read from the database 220. The demand forecast value is calculated as 24-hour time series data.

Next, in step S104, the planning problem solving unit 213 solves the planning problem shown below, and instructs the treated water distribution device 14 of the amount of treated water to be distributed to the water regeneration treatment device 15 according to the solution.

(1-2-3) Planning Problem Here, a method for solving the planning problem by the planning problem solving unit 213 will be described.

First, the predicted values for each water quality of the treated water 2 calculated by the treated water quality predicting unit 211 in step S402 are XBODin (t), XTNin (for the BOD concentration, TN concentration, TP concentration, and SS concentration, respectively. t), XTPin (t), and XSSin (t). In each function, t indicates a time, which corresponds to any of 0, 1,..., 24, and when there is no special designation, also at the time t in other functions shown below. It is the same. For example, XBODin (5) indicates the predicted value of the BOD concentration of the treated water 2 at 5 o'clock.

Next, let V (t) be the amount of reclaimed water stored in the distribution reservoir 16, and XBOD (t), XTN for the BOD concentration, TN concentration, TP concentration, and SS concentration of the reclaimed water stored in the distribution reservoir 16, respectively. Let (t), XTP (t), and XSS (t). Further, the flow rate of the treated water 2 sent from the treated water distribution device 14 to the water regeneration treatment device 15, that is, the planned value that is the solution to this planning problem is defined as Q (t). In addition, the demand prediction value of the reclaimed water calculated by the reclaimed water demand prediction unit 212 in step S403 is defined as Qd (t). The initial values (values when t = 0) of the functions V (t), XBOD (t), XTN (t), XTP (t), and XSS (t) are V0, XBOD0, XTN0, and XTP0, respectively. And XSS0.

Furthermore, the removal rate of each water quality component (BOD, TN, TP, and SS) by the water regeneration treatment in the water regeneration treatment device 15 is KBOD, KTN, KTP, and KSS, respectively. In addition, KBOD, KTN, KTP, and KSS may not be constants, and may be a variable using, for example, Q (t) indicating the flow rate of the treated water 2 fed to the water regeneration treatment device 15.

Thus, when each function and each value are defined, the relationship shown in the equation (1) is established for the storage amount V (t) of the reservoir 16.

In addition, regarding the BOD concentration XBOD (t), TN concentration XTN (t), TP concentration XTP (t), and SS concentration XSS (t) of the reclaimed water stored in the distribution reservoir 16, equations (2) to (5) The following relationship is established.

In the above formulas (1) to (5), given the planned value Q (t), the storage amount V (t) of the reservoir 16 and the concentration XBOD (t), XTN of each water quality component of the reservoir 16 (T), XTP (t), and XSS (t) are calculated. Then, by appropriately setting the planned value Q (t), the concentration (XBOD (t), XTN (t), XTP (t), and XSS (t) of the water quality components of the reclaimed water stored in the distribution reservoir 16 )), It is possible to keep the maximum value predicted within the next 24 hours.

In step S404, the planning problem solving unit 213 selects the concentration of water quality component (XBOD (t), XTN (t), XTP (t) in the time series of 24 hours for the water quality component to be removed selected in step S401. ), Or XSS (t)), so that the maximum value is minimized using an optimization calculation such as a genetic algorithm (GA) or a genetic program (GP). ) Is calculated. When this optimization calculation is performed, the planned value Q (t) is not less than 0 and not more than the inflow amount of the treated water 2 flowing from the collection sedimentation basin 3, and the reservoir storage amount V (t) is a predetermined upper limit. A constraint condition is set such that the value is between the value VMAX and the lower limit value VMIN. Further, in this optimization calculation, the plan value Q (t) is calculated so that the treated water 2 when the concentration of the selected water quality component becomes low is used preferentially.

Then, the planning problem solving unit 213 sends the treated water 2 to the water regeneration treatment device 15 according to the planned value Q (t) (t = 1, 2,..., 24) calculated by the above optimization calculation. Then, the treated water distribution device 14 is instructed.

(1-3) Effects of this Embodiment In such a water treatment plant operation system 20, the quality of the treated water 2 generated by the sewage treatment varies depending on the amount of sewage 1 flowing into the settling basin 11 first. However, the treated water from the treated water distribution device 14 to the water regeneration treatment device 15 so that the maximum value of the water quality component selected by the planning problem solving unit 213 is minimized and the demand for the reclaimed water is satisfied. The amount of water supply 2 can be controlled.

Moreover, in such a water treatment plant operation system 20, the plan value Q (t) is calculated so that the treated water 2 when the concentration of the water quality component selected in the optimization calculation is low is used preferentially. Therefore, the processing cost concerning the water regeneration process performed in the water regeneration processing apparatus 15 in order to implement | achieve the target water quality of the reclaimed water can be reduced.

Such a water treatment plant operation system 20 can preferentially feed the treated water 2 having a good water quality from the treated water distribution device 14 to the water regeneration treatment device 15 to achieve a desired water quality. In the production of reclaimed water, it is possible to reduce the processing cost for water regeneration treatment.

(2) Second Embodiment (2-1) Configuration According to this Embodiment As shown in FIG. 5, the water treatment plant operation system 30 according to the second embodiment includes a control device 310, a control device 310, and a control device 310.

Databases

320 and 330 that provide stored data to the control unit 310 and an input unit 340 that transmits an input signal to the control device 310.

For example, the control device 310 controls each part in the control device 310 by executing a program and gives a water supply instruction to the treated water distribution device 14 (Central Processing Unit) (not shown), and the CPU executes the program This is realized by a computer having a memory (not shown) in which a program is loaded and used, and a storage device (not shown) for storing various data and programs.

The control device 310 has a treated water quality prediction unit 311, a reclaimed water demand prediction unit 312, and a planning problem solving unit 313 as its functional configuration.

The treated water quality prediction unit 311 performs a predetermined calculation process (to be described later with reference to FIG. 7) based on past performance data on the inflow amount and water quality of the sewage 1, and a predetermined time (for example, 0) after the present time. It is predicted what value the quality of the treated water 2 will take at each time (from time to 24:00).

The reclaimed water demand prediction unit 312 predicts how much reclaimed water 3 is in demand at a predetermined time (for example, from 0:00 to 24:00) after the present based on past performance data.

The planning problem solving unit 313 controls the amount of water supplied to the water regeneration treatment device 15 by the treated water distribution device 14. The planning problem solving unit 313 solves the planning problem based on the predicted values calculated by the treated water quality prediction unit 311 and the reclaimed water demand prediction unit 312, and instructs the treated water distribution device 14 of the water supply amount according to the solution.

The database 320 is a storage device and stores time-series data regarding the demand for reclaimed water. The time series data related to the demand for reclaimed water is created by the same process as the time series data of the same name used in the first embodiment and stored in advance.

The database 330 is a storage device and stores time-series data related to the inflow amount of the sewage 1 and time-series data related to the concentration of the water quality component of the sewage 1 based on past performance data in the water treatment plant 10. The time series data relating to the inflow amount of the sewage 1 and the time series data relating to the concentration of the water component of the sewage 1 are the same as the time series data of the treated water 2 used in the first embodiment (step S102 in FIG. 2). Created and stored in advance.

The input unit 340 is an input device in which an input operation and data input from a user are performed in the same manner as the input unit 210, and an input signal corresponding to the input content is transmitted to the control device 310.

(2-2) Processing according to the present embodiment Hereinafter, a processing procedure in which the water treatment plant operation system 30 plans a water supply amount in the water treatment plant 10 will be described with reference to FIG.

First, in step S201, a water quality component that is particularly desired to be removed is selected from the water quality component items by a user input operation on the input unit 330. Each item of the water quality component is, for example, BOD, total nitrogen (TN), total phosphorus (TP), or solid suspended matter (SS). At this time, a predetermined screen may be displayed on a display unit (not shown) to allow the user to select a removal item.

Next, in step S 202, the treated water quality prediction unit 311 reads time-series data regarding the inflow amount of the sewage 1 from the database 330. And the treated water quality prediction part 311 is 24 hours after the present of the sewage 1 based on the time series data corresponding to the present season and the day of the week in relation to the inflow amount of the sewage 1 read from the database 330. The inflow prediction value for the minute is calculated as time-series data for 24 hours.

Next, in step S 203, the treated water quality prediction unit 311 reads time-series data relating to the concentration of water quality components in the sewage 1 from the database 330. Then, the treated water quality prediction unit 311 selects each water quality of the sewage 1 based on the time series data corresponding to the current season and day of the week among the time series data related to the concentration of the water quality components of the sewage 1 read from the database 330. A water quality prediction value for 24 hours after the present (BOD concentration, TN concentration, TP concentration, and SS concentration) is calculated as time-series data for 24 hours. In addition, in the predicted water quality value of the sewage 1 calculated in step S203, the water temperature of the sewage 1 may be added to the item in addition to the above water quality.

Next, in step S204, the treated water quality prediction unit 311 calculates a predicted water quality value of the treated water 2 using the predicted inflow amount and the predicted water quality value for the sewage 1 calculated in steps S202 and S203.

(2-2-1) Calculation of water quality prediction value of treated water FIG. 7 schematically illustrates a mathematical model for calculating the BOD concentration as an example of a method of calculating the water quality prediction value by the treated water quality prediction unit 311. Yes. FIG. 7 shows a dynamic model in which the inflow amount and quality of the sewage 1 are input and the water quality of the treated water 2 is output. The dynamic model includes the first mathematical model 81 and the second mathematical model. It consists of a mathematical model 82.

First, the treated water quality prediction unit 311 inputs an inflow prediction value (Qin) and a water quality prediction value (BODin) for the sewage 1 to the first mathematical model 81. The first mathematical model 81 has a static relationship established between the inflow amount of the sewage 1, the water quality of the sewage 1, and the water quality of the treated water 2 in a steady state where the inflow amount of the sewage 1 is constant. It is a model to prescribe. As the first mathematical model 81, a two-dimensional table prepared in advance is used, and a water quality component concentration (for example, BOD concentration: BODout1) of the treated water 2 generated in a steady state is output. The table data constituting the two-dimensional table used in the first model 81 should be created based on the measurement data of the steady-state sewage 1 inflow, the sewage 1 water quality, and the treated water 2 water quality. And stored in the database 330 in advance.

Next, as shown in FIG. 7, the treated water quality prediction unit 311 inputs the BOD concentration (BODout1) in the treated water 2 in the steady state output from the first mathematical model 81 to the second mathematical model 82. . The second mathematical model 82 is a mathematical expression that applies a delay process to an input value, and is specifically a transfer function of “dead time + m-th order delay” (S represents a Laplace operator). The transfer function of the second mathematical model 82 outputs the BOD concentration (BODout2) in the treated water 2 at the time of transition. The BOD concentration in the treated water 2 at the time of transition corresponds to the predicted value of the BOD concentration in the treated water 2. Hereinafter, the first mathematical model 81 and the second mathematical model 82 are collectively referred to as a water quality calculation model.

Here, “dead time + m-th order delay” means the timing at which the inflow amount of the sewage 1 changes and the accompanying change, as described with reference to FIGS. 3A to 3D in the first embodiment. It is the relationship which shows the difference with the timing of the water quality change of the treated water 2. FIG. This timing shift occurs because time is required due to chemical reaction or retention in the sewage treatment performed on the sewage 1 in the first settling basin 11, the activated sludge treatment tank 12 and the collection settling basin 13, and the sewage 1 After a while after the inflow amount increases, the water quality of the treated water 2 decreases. In addition, as shown in FIG. 3, the waveform indicating the water quality change of the treated water 2 does not appear as it is as the waveform indicating the change in the inflow amount of the sewage 1, but appears as a tanned waveform. The second mathematical model 82 is a transfer function that approximately represents such a characteristic of “dead time + m-th order delay”.

In addition, as for the transfer function of the 2nd mathematical model 82, the parameter T1, T2, and m take the value from which the parameter T1, T2, and m differ according to the target water quality component like the table 92 shown in FIG. Differences in parameter values due to water quality components are due to various factors represented by differences in the speed of chemical reactions. The table 92 in FIG. 8 includes a water quality component column 92A in which the target water quality component is described, a dead time column 92B in which the value of the dead time T1 is written, a time constant column 92C in which the value of the time constant T2 is written, and It has an order column 92D in which the order is described, and a predetermined numerical value is described in each column. The table 92 may be stored in a memory (not shown) in the control device 310 or may be stored in the database 330, for example.

Moreover, since the value described in each column of the table 92 is affected by the water temperature of the sewage 1, the dissolved oxygen amount, etc., a plurality of tables 92 for various water temperatures are stored, and the water quality prediction in step S204 is performed. You may make it utilize at the time of calculation.

As shown above, in step S204, the treated water quality prediction unit 311 performs a calculation process for each water quality component (BOD concentration, TN concentration, TP concentration, and SS concentration) to calculate a predicted water quality value of the treated water 2. To do.

Next, in step S205, the reclaimed water demand prediction unit 312 reads time-series data regarding the demand amount of the reclaimed water 3 from the database 320. Then, the reclaimed water demand prediction unit 312 is based on the time series data corresponding to the current season and day of week among the time series data relating to the demand amount of the reclaimed water 3 read from the database 320, and for 24 hours after the present of the reclaimed water 3. Is calculated as 24-hour time-series data.

Next, in step S 206, the planning problem solving unit 313 is based on the water quality prediction value of the treated water 2 calculated by the treated water quality prediction unit 311 and the demand prediction value of the reclaimed water 3 calculated by the reclaimed water demand prediction unit 312. Thus, the planning problem is solved by the same processing as the planning problem solving unit 213 in the first embodiment. Explanation of the solution of the planning problem is omitted. Then, the plan problem solving unit 313 instructs the treated water distribution device 14 of the amount of treated water 2 to be distributed to the water regeneration treatment device 15 according to the solution (plan value).

(2-3) Effects of this Embodiment In such a water treatment plant operation system 30, a water quality calculation model using a transfer function that can more closely approximate the phenomenon of “dead time + m-order delay” is constructed in advance. Since the water quality prediction value of the treated water 2 is calculated by the calculation model, even if an unexpected situation occurs, the accuracy is more accurate than when the water quality prediction value of the treated water 2 is calculated based on past performance data. It is possible to calculate a water quality prediction value of high treated water. As a result, the accuracy of the operation plan of the reclaimed water in the water treatment plant 10 can be increased, and an effect of further reducing the treatment cost for the water reclaim process can be expected.

(3) Third Embodiment (3-1) Configuration according to this Embodiment As shown in FIG. 9, the water treatment plant operation system 40 according to the third embodiment is the water treatment plant shown in FIG. In addition to the control device 410, the

databases

420 and 430, and the input unit 440 similar to the configuration of the operation system 30, an inflow / water quality acquisition unit 450, a database 460, and a table data calculation unit 470 are provided. The description of the same configuration as the configuration of the water treatment plant operation system 30 is omitted.

The water treatment plant 10 of FIG. 9 is provided with a sensor 27 for measuring the inflow amount and quality of the sewage 1 flowing into the first settling basin 11 in the flow path before the first settling basin 11. A sensor 28 that measures the inflow amount and quality of the treated water 2 flowing into the treated water distribution device 14 is provided in a flow path between the treated water distribution device 14 and the treated water distribution device 14. The inflow amount or water quality measurement results by the

sensors

27 and 28 are transmitted to the inflow amount / water quality data acquisition unit 450.

In the water treatment plant operation system 40, the inflow amount / water quality data acquisition unit 450 acquires the measurement result of the inflow amount and water quality of the sewage 1 by the sensor 27 provided in the water treatment plant 10, and based on the measurement result. Generate time-series data about the inflow and quality of sewage 1. The inflow / water quality acquisition unit 450 generates, for example, hourly time series data over the past several months and stores it in the database 460. The inflow / water quality data acquisition unit 450 acquires the measurement result of the water quality of the treated water 2 by the sensor 28 provided in the water treatment plant 10, and the time-series data about the inflow amount and the water quality of the sewage 1 Similarly, time-series data about the water quality of the treated water 2 is generated and stored in the database 460. Generation of these time-series data by the inflow / water quality acquisition unit 450 is performed based on the measurement results of the

sensors

27 and 28 constantly or periodically, and the generated time-series data is accumulated in the database 460.

The table data calculation unit 470 calculates the table data of the water quality calculation model based on the time series data about the inflow amount and the water quality of the sewage 1 stored in the database 460. The table data of the water quality calculation model is two-dimensional table data used in the first mathematical model 81 of FIG. 7, and parameters (dead time T1, time constant) of the table 92 used in the second mathematical model 82. T2 and the value of order m). The table data of the water quality model is stored in the database 430.

(3-2) Treatment according to the present embodiment The treatment procedure for the water treatment plant operation system 40 to plan the amount of water to be fed in the water treatment plant 10 is the same as the treatment of the water treatment plant operation system 30 according to the second embodiment (FIG. 6). ), And only the process for calculating the table data of the water quality calculation model is different in the calculation of the predicted water quality of the treated water (step S204 in FIG. 6).

First, the processing until the water quality component to be specifically removed is selected by the user and the inflow amount and the water quality predicted value in the sewage 1 are calculated by the treated water quality prediction unit 411 is the process shown in steps S201 to S203 in FIG. This is the same and will not be described.

Next, the water quality prediction value of the treated water is calculated by the treated water quality prediction unit 411. The table data calculation unit 470 uses the table data calculation unit 470 for the water quality calculation model (the first mathematical model 81 and the mathematical model 82) used there. Calculate table data of water quality calculation model.

(3-2-1) Table Data Calculation of Water Quality Calculation Model As shown in FIG. 10, first, in step S301, the table data calculation unit 470 determines the inflow amount and water quality of the sewage 1 stored in the database 460. Referring to the time-series data and the time-series data about the water quality of the treated water 2, it is determined whether or not the time-series data measured at various dates and times are data measured during steady operation of the water treatment plant 10. (Normal determination).

Here, an example of steady determination by the table data calculation unit 470 will be described with reference to FIG. In FIG. 11, a sewage inflow measurement value 93 A indicating measurement data regarding the inflow amount of sewage 1, a sewage water quality measurement value 93 B indicating measurement data regarding the water quality of sewage 1, and measurement data regarding the water quality of treated water 2. The treated water quality measurement value 93C is shown. For example, the table data calculation unit 470 acquires measurement data every 6 hours from the database 460, and compares the measurement data at t and the measurement data at (t + 6). In the comparison of the measurement data, the table data calculation unit 470 has a fluctuation amount or a fluctuation rate exceeding a preset threshold for each of the sewage inflow measurement value 93A, the sewage water quality measurement value 93B, and the treated water quality measurement value 93C. Judge whether it is. When the fluctuation amount or the fluctuation rate is within the threshold value, the table data calculation unit 470 determines that the measurement data is data measured during steady operation of the water treatment plant 10.

The table data calculation unit 470 repeats such steady state determination, and extracts a plurality of 6-hour time series data when the water treatment plant 10 is in a steady operation state.

Next, in step S302, the table data calculation unit 470 averages each time-series data in the steady operation state extracted in step S301, and the average sewage inflow amount indicating the average of the inflow amount of the sewage 1, the water quality of the sewage 1 An average sewage quality indicating an average concentration and an average treated water quality indicating an average water concentration of the treated water 2 are calculated. Since a plurality of time-series data in the steady operation state are extracted in step S301, a plurality of combinations of average sewage inflow, average sewage quality, and average treated water quality are obtained. The table data calculation unit 470 calculates new table data used in the first mathematical model 81 based on the combination of the average sewage inflow amount, the average sewage water quality, and the average treated water quality obtained as described above. . New table data is calculated for each water quality component.

On the other hand, in step S302, the table calculation unit 470 calls the sewage inflow amount and sewage quality measurement time series at a certain time from the sewage inflow amount and sewage water quality time series stored in the database 460, and calls them the first time series. As an input value to the mathematical model 81, the first mathematical model 81 and the second mathematical model 82 are calculated for each water quality component, and the water quality of the treated water 2 is predicted. At this time, the table data calculation unit 470 measures the water quality of the treated water 2 corresponding to the sewage inflow amount and the measurement time series of the sewage water quality from the time series data about the water quality of the treated water 2 stored in the database 460. A series (measured values at the same time) is acquired, and the water quality prediction value of the treated water 2 calculated by the second mathematical model 82 matches the water quality measured value of the treated water 2 obtained from the database 460. Then, the values of the parameters (dead time T1, time constant T2, and order m) of the table 92 are calculated by nonlinear optimization calculation. Such parameter values, that is, the table data used in the second mathematical model are calculated for each water quality component.

In step S303, the table data calculation unit 470 rewrites the previous table data stored in the database 430 with the new table data calculated in step S302. By rewriting the table data as described above, the table data can maintain a value suitable for the characteristics or state of the water treatment plant 10.

The treated water quality prediction unit 411 uses the table data of the water quality calculation model calculated by the process of FIG. 10, and calculates the predicted water quality value of the treated water 2 in the same manner as the process in the second embodiment other than that. To do.

Then, the reclaimed water demand prediction unit 412 calculates the demand prediction value of the reclaimed water 3, and the planning problem solving unit 413 solves the planning problem based on the water quality prediction value of the treated water 2 and the demand prediction value of the reclaimed water 3, and the solution The processing until the amount of treated water 2 to be distributed to the water regeneration treatment device 15 according to (planned value) is controlled is the same as the processing shown in steps S205 to S206 in FIG.

(3-3) Effects of the Present Embodiment Such a water treatment plant operation system 40 is a measurement in which table data used in a water quality calculation model for predicting the water quality concentration of the treated water 2 is measured online. Since the value is calculated and corrected, the situation in the water treatment plant 10 can be flexibly dealt with. As a result, compared to the water treatment plant operation system 20 according to the first embodiment and the water treatment plant operation system 30 according to the second embodiment, a predicted water quality value of the treated water 2 that is closer to the actual value is calculated. The water treatment plant 10 can be operated with high accuracy. For example, even when the characteristics of the water treatment plant 10 change over time or when the control method of the water treatment plant 10 is changed, the table data is changed to be changed along the measurement values. The planned value can be calculated by a mathematical model using the table data.

In addition, the water treatment plant operation system 30 can calculate the plan value with higher accuracy because the parameters of the water quality calculation model are kept up-to-date according to the measured values. The accuracy of the operation plan can be improved. As a result, an effect of further reducing the processing cost of the water regeneration process can be expected.

(4) Other Embodiments In the water treatment

plant operation system

20, 30, or 40 according to the first to third embodiments, the

input unit

230, 340, or 440 is provided outside the

control device

210, 310, or 410, respectively. However, the present invention is not limited to this, and may be provided inside the

control device

210, 310, or 410, respectively. Further, the

input unit

230, 340, or 440 is also used for the database 220 according to the first embodiment, the

databases

320 and 330 according to the second embodiment, or the

databases

420, 430, and 460 according to the third embodiment. Similarly, it may be provided inside the

control device

210, 310 or 410, respectively.

In the water treatment

plant operation system

30 or 40 according to the second or third embodiment, a case where a plurality of databases are provided has been described. However, the present invention is not limited to this, and various data are stored in one database. The system cost may be reduced by reducing the number of storage devices so as to be integrated and stored. Conversely, various data may be distributed and stored in more databases to improve the processing speed when a large amount of data is stored.

The present invention can be applied to a water treatment plant operation system and a water supply amount planning method for managing a water treatment plant that purifies sewage and produces reclaimed water that can be reused.

DESCRIPTION OF SYMBOLS 1 Sewage 2 Treated water 3 Reclaimed water 10 Water treatment plant 11 Initial sedimentation tank 12 Activated sludge treatment tank 13 Final sedimentation tank 14 Treated water distribution apparatus 15 Water regeneration treatment apparatus 16 Distribution tank 17 Coagulant storage tank 21 Blower 22-26

Pump

27, 28

Sensors

20, 30, 40 Water treatment

plant operation system

210, 310, 410

Controller

211, 311, 411 Treated water

quality prediction unit

212, 312, 412 Reclaimed water

demand prediction unit

213, 313, 413 Planning

problem solving unit

220, 320 , 330, 420, 430, 460

Database

230, 340, 440 Input unit 450 Inflow / water quality acquisition unit 470 Table data calculation unit 81 First mathematical model 82 Second mathematical model

Claims

In a water treatment plant operation system for managing a water treatment plant that produces sewage by performing sewage treatment on sewage, and performing water regeneration treatment on the treated water to produce reclaimed water,
A treated water quality prediction unit for predicting the quality of the treated water generated by the sewage treatment;
A reclaimed water demand prediction unit for predicting the reclaimed water demand;
Based on the treated water quality prediction value predicted by the treated water quality prediction unit, a planned value is calculated by a predetermined calculation, and the amount of treated water subjected to water regeneration treatment in the water treatment plant is determined according to the planned value. A planning problem solving section to control;
With
The plan value calculated by the plan problem solving unit is such that the amount of reclaimed water produced by the water regeneration process from the treated water according to the plan value satisfies the demand forecast value predicted by the reclaimed water demand forecast unit. A water treatment plant operation system characterized by
The said treated water quality prediction part predicts the quality of the treated water produced | generated after the present based on the performance data about the quality of the said treated water produced | generated in the past. Water treatment plant operation system.
The treated water quality prediction unit
Predict the inflow and quality of sewage that will flow in
The water treatment plant operation system according to claim 1, wherein the water quality of treated water generated after the present time is predicted based on the predicted predicted inflow amount of sewage and the predicted water quality value.
The treated water quality prediction unit
The result of measuring the concentration of one or more predetermined water quality components for treated sewage treated in the past is stored as time series data classified by time system parameters,
The water treatment plant operation system according to claim 1, wherein water quality of treated water generated after the present time is predicted based on the stored time series data.
The treated water quality prediction unit
The water treatment plant according to claim 3, wherein the water quality of the treated water generated after the present time is predicted by a dynamic model having the sewage inflow and water quality as inputs and the treated water quality as outputs. Operational system.
The dynamic model includes a first mathematical model that defines a static relationship between an inflow amount and quality of sewage in the water treatment plant in a steady state and a quality of treated water in the steady state, and the steady state A second mathematical model defining a dynamic relationship between the quality of the treated water in the state and the quality of the treated water in the transient water treatment plant;
The first mathematical model outputs the water quality of the treated water in the steady state with the inflow amount and the water quality of the sewage as inputs.
The second mathematical model receives the quality of treated water in the steady state output from the first mathematical model and outputs the quality of treated water in the transient water treatment plant. The water treatment plant operation system according to claim 5.
An inflow amount / water quality acquisition unit for acquiring measured values of the inflow amount of the sewage from the water treatment plant, the quality of the sewage, and the quality of the treated water;
The treated water quality prediction unit calculates table data used in the first mathematical model and the second mathematical model based on the measurement value acquired by the inflow / water quality acquisition unit, The water quality of the treated water generated after the present is predicted by the dynamic model including the first mathematical model and the second mathematical model using the calculated table data. The water treatment plant operation system described.
Sewage treatment is performed on sewage to produce treated water, and the water treatment plan is to produce the reclaimed water by subjecting the treated water to water regeneration treatment. In the method
A demand amount prediction step for predicting the demand amount of the reclaimed water;
A treated water quality prediction step for predicting the quality of the treated water generated by the sewage treatment;
A plan value calculating step of calculating a plan value by a predetermined calculation based on the predicted water quality predicted value of the treated water;
A water supply amount control step for controlling the amount of treated water subjected to water regeneration treatment in the water treatment plant according to the calculated plan value;
With
The plan value calculated in the plan value calculation step is such that the amount of reclaimed water produced from the treated water according to the plan value by the water regeneration process satisfies the demand prediction value predicted in the demand amount prediction step. A water supply planning method characterized by:
The water quality of the treated water produced | generated after the present is estimated based on the results data about the water quality of the treated water produced | generated in the past in the said treated water quality prediction step. Water supply planning method.
In the treated water quality prediction step,
Predict the inflow and quality of sewage that will flow in
The water supply amount planning method according to claim 8, wherein the water quality of the treated water generated after the present time is predicted based on the predicted inflow amount predicted value and the predicted water quality value of the sewage.
In the treated water quality prediction step,
The result of measuring the concentration of one or more predetermined water quality components for treated sewage treated in the past is stored as time series data classified by time system parameters,
The water supply amount planning method according to claim 8, wherein the quality of treated water generated after the present time is predicted based on the stored time-series data.
In the treated water quality prediction step,
The water supply amount plan according to claim 10, wherein the water quality of the treated water generated after the present time is predicted by a dynamic model having the sewage inflow and water quality as inputs and the treated water quality as outputs. Method.
The dynamic model includes a first mathematical model that defines a static relationship between an inflow amount and quality of sewage in the water treatment plant in a steady state and a quality of treated water in the steady state, and the steady state A second mathematical model defining a dynamic relationship between the quality of the treated water in the state and the quality of the treated water in the transient water treatment plant;
In the first mathematical model, the inflow amount and quality of the sewage are input, and the quality of treated water in the steady state is output.
In the second mathematical model, the quality of the treated water in the water treatment plant in the transient state is output using the quality of the treated water in the steady state outputted from the first mathematical model as an input. The water supply amount planning method according to claim 12.
An inflow / water quality acquisition step of acquiring respective measured values of the inflow of the sewage from the water treatment plant, the quality of the sewage, and the quality of the treated water;
In the treated water quality prediction step,
Calculate table data used in the first mathematical model and the second mathematical model based on the measured value obtained in the inflow / water quality obtaining step,
The water quality of the treated water generated after the present is predicted by the dynamic model including the first mathematical model and the second mathematical model using the calculated table data. Water quantity planning method described in 1.