JP6867851B2 - Emission control device and emission control program - Google Patents

Description

The present invention relates to a sewage treatment plant control device and a sewage treatment plant control program.

In urban areas, sewage discharged from households and the like flows into a sewage treatment plant via a pipe buried underground. Stormwater also flows into public water areas such as rivers via underground culverts. The stormwater culvert may be buried independently of the sewage culvert. However, in urban areas where sewerage infrastructure has been developed in advance, rainwater often joins sewage pipes. In the latter case, if a large amount of rainfall continues, the rainwater mixes with the sewage, causing phenomena such as flooding of roads, flooding of sewage treatment plants, and untreated water being discharged into rivers. Therefore, a pumping station is usually installed as an intermediate facility on the upstream side of the sewage treatment plant. Part of the sewage (rainwater + sewage) that has flowed into the pumping station is discharged to the sewage treatment plant, while the rest is discharged (discharged) to public water areas such as rivers.

The drainage pump operation support device of Patent Document 1 predicts the water level in the pipe and the inflow amount to the pumping station, and determines the starting timing and the discharging amount of the pump that discharges sewage from the pumping station. At this time, the drainage pump operation support device of Patent Document 1 determines the discharge amount so that the water level of the pipe does not exceed the dangerous level.

Japanese Unexamined Patent Publication No. 2003-239372

However, the actual water level value and the predicted water level value used as the premise that the drainage pump operation support device of the cited document 1 determines the discharge amount of the pump include some errors. This is because, in reality, the accuracy of the water level gauge and the flow meter is limited, and the accuracy of the model for predicting the water level and the inflow is also limited. That is, as a result, the device predicted the water level to be more dangerous than the actual value (lower than the actual water level), or predicted the water level to be safer than the actual value (higher than the actual water level). I can only tell after the fact. If the device predicts the water level on the dangerous side, the pump will not exert the actually required discharge amount, and the road and the pumping station will be flooded with sewage.
Therefore, an object of the present invention is to determine the discharge amount of rainwater or the like from a pumping station of a sewage treatment plant from the safety side.

The sewage treatment plant control device of the present invention has a simulation unit that predicts the water level of the sewage storage facility in time series in a future period, and a value that is large enough to meet a predetermined standard among the predicted water levels. A safety mode water level reference unit as a representative value, a normal mode water level reference unit in which a water level other than the representative value among the predicted water levels is a variable value of the water level during the period, and a safety mode water level reference unit or a normal mode water level reference unit. A mode determination unit for determining which to select is provided, and the representative value is an invariant representative value whose value is constant during the period, and the simulation unit is a sewage storage facility based on the invariant representative value during the period. It is characterized by determining the amount of sewage discharged from the sewage.
Other means will be described in the form for carrying out the invention.

According to the present invention, the discharge amount of rainwater or the like from the pumping station of the sewage treatment plant can be determined from the safety side.

It is a figure explaining the environment of this embodiment. It is a figure explaining the outline of the information processing of this embodiment. (A) is an example of the control reference water level information in the normal mode. (B) is an example of the control reference water level information of the safety mode. (A) is a diagram illustrating a risk database. (B) is an example of a discharge amount matrix. (C) is a diagram for explaining the content of the risk. It is a figure explaining the structure of the sewage treatment plant control device. It is a flowchart of a processing procedure.

Hereinafter, a mode for carrying out the present invention (referred to as “the present embodiment”) will be described in detail with reference to figures and the like. This embodiment is an example of discharging the sewage stored in the pumping station of the sewage treatment plant by a pump. However, the present invention is also applicable to the case where sewage is discharged (dropped) by utilizing natural water pressure without using a pump. For example, the amount of sewage discharged may be adjusted by adjusting the cross-sectional area of the opening of the discharge port, the opening degree of the valve, and the like without using a pump. "Emission amount" is a concept including these emission amounts and discharge amounts in a narrow sense.

(Environment of this embodiment)
FIG. 1 is a diagram illustrating an environment of the present embodiment. The sewage treatment zone 51 is, for example, a predetermined area in an urban area. Households, offices, factories, etc. existing in the sewage treatment zone 51 discharge sewage 52 from kitchens, toilets, production sites, and the like. The sewage 52 flows into the sewer pipe 54. The rainwater 53 that has fallen in the sewage treatment area 51 also flows into the sewage pipe 54. As described above, there is a case where the sewage 52 and the rainwater 53 do not merge at the sewage pipe 54, and each of them has a completely different system (split type). This embodiment is based on the premise that the sewage 52 and the rainwater 53 merge at the sewer pipe 54 (merging type). In this embodiment, a mixture of rainwater and sewage may be referred to as "sewage".

The sewage pipe 54 is buried underground, and beyond that, it reaches the pumping station 3. The diameter of the sewer pipe 54 becomes larger and the depth becomes deeper as it goes downstream. When it reaches a certain depth, the sewage is pumped vertically (not shown). Then, the sewage passes through the sewage pipe 54 from the level after being pumped, and finally reaches the pumping station 3.

When the sewage reaches the pumping station 3, it is first stored in the sand basin 45. In the sand basin 45, sand, dust, etc. contained in the sewage are settled. Next, the supernatant of the sewage flows into the pump well 46. The pump well 46 corresponds to the “sewage storage facility”. A water level gauge 41, a flow meter 42, one or more sewage pumps 43, and one or more rainwater pumps 44 are installed in the pump well 46. The sewage pump 43 discharges the sewage stored in the pump well 46 to the sewage treatment plant 55. The rainwater pump 44 discharges the sewage stored in the pump well 46 to a public water area 56 such as a river. The flow meter 42 measures the flow rate (volume per unit time) of the sewage flowing from the sand basin 45 into the pump well 46. The water level gauge 41 measures the water level of the sewage in the pump well 46.

Although not shown in detail, at the sewage treatment plant 55, first, the sewage is stored in the settling tank for a certain period of time. Then, impurities are precipitated. Next, the sewage from which impurities have been separated is mixed with activated sludge (including bacteria) and then blown with air. Then, bacteria decompose organic matter and the like in the sewage. Then, the sewage is stored again in another settling tank for a certain period of time. Then, the decomposed residue is precipitated. Finally, the sewage after the residue is separated is mixed with a disinfectant such as chlorine and then discharged into the public water area 56. On the other hand, the sewage discharged by the rainwater pump 44 is directly discharged to the public water area 56 without passing through the sewage treatment plant 55. This sewage is discharged to the public water area 56 in a sand basin 45 in a state where only the minimum treatment is performed (simple treatment state) without going through a treatment using bacteria (high-grade treatment).

When there is a large amount of rainfall and the total amount (total discharge amount) of the discharge amount of the sewage pump 43 and the discharge amount of the rainwater pump 44 is large, the sewage easily flows downstream of the pumping station 3. Therefore, in the sewage treatment zone 51 on the upstream side, for example, the road does not inundate (sewage overflows). Moreover, the pumping station 3 is not submerged. However, treatment defects occur due to insufficient time for performing high-grade treatment at the sewage treatment plant 55. Alternatively, a large amount of sewage is discharged into the public water area 56 in a simple treatment state. On the contrary, when the total discharge amount of the sewage pump 43 and the rainwater pump 44 is small, no treatment failure occurs and a large amount of sewage is not discharged to the public water area 56 in a simple treatment state. However, the sewage tends to stay upstream of the pumping station 3, the sewage treatment section 51 is flooded, and the pumping station 3 is also submerged.

Regarding the balance between the discharge amount of the sewage pump 43 and the discharge amount of the rainwater pump 44, even if the total discharge amount of both is the same, if the discharge amount of the rainwater pump 44 is smaller, a large amount of sewage is in a simple treatment state. It is unlikely that it will be released into public water area 56. However, there is a high possibility that treatment defects will occur at the sewage treatment plant 55. On the contrary, when the discharge amount of the sewage pump 43 is smaller, the possibility that a treatment failure occurs in the sewage treatment plant 55 is small. However, there is a high possibility that a large amount of sewage will be discharged into the public water area 56 in a simple treatment state.

(Trade-off between risks)
The entire water system of the sewage treatment area 51, pumping station 3, sewage treatment plant 55 and public water area 56 includes (1) inundation risk of sewage treatment area 51, (2) submersion risk of pumping station 3, and (3) sewage treatment plant. There is a risk of poor treatment of 55 and (4) a risk of pollution of public water bodies 56. Of these, (1) and (2) often occur at the same time, so these two risks are represented by (1). Then, the risks of (1), (3) and (4) are in a trade-off relationship with each other. Based on the pumping station 3, (1) is the risk on the upstream side, and (3) and (4) are the risks on the downstream side. Which of the three risks should be prioritized and reduced depends on what value the discharge amount of the sewage pump 43 and the discharge amount of the rainwater pump 44 are determined. The unit of each risk is generally the amount of money (expected damage amount, etc.).

The outline of the information processing of the present embodiment will be described with reference to FIG. In the process of explaining FIG. 2, reference is made to FIGS. 1, 3 and 4 as necessary. The details of information processing will be described later as an explanation of FIG.

(1st stage)
The sewage treatment plant control device 1 (see FIG. 5) of the present embodiment creates the control reference water level information 31. The control reference water level is the water level of the pump well 46, which is a prerequisite for the sewage treatment plant control device 1 to determine the discharge amount of the pumps (reference numerals 43 and 44). In general, the higher the control reference water level, the more the sewage treatment plant control device 1 attempts to increase the discharge rate of the pump and reduce the risk (detailed later). The control reference water level information 31 is a time-series control reference water level. The time series here includes past time points (t- ₂ , t _-1 ), current _{time points (t 0} ) and future time points (t ₁ , t ₂ , t ₃ , t ₄ ).

The sewage treatment plant control device 1 determines the control reference water level at the past time point and the present time based on the internal measurement value 61. The internal measured value 61 is a past and present actual value of the water level gauge 41. The sewage treatment plant control device 1 predicts the control reference water level at a future time point as follows based on the external measurement value 62 and the internal measurement value 61 (current total discharge amount). The external measurement value 62 is, for example, meteorological information about the sewage treatment area 51.

For example, the sewage treatment plant control device 1 _{assumes that during the period from the current time t 0} to the current time t ₁ , the rainfall predicted by the meteorological information continued to fall on the sewage treatment zone 51, and the total discharge amount continued at the current level. .. Sonouede sewage treatment plant controller 1 at time t ₁ sewage to predict whether reaching the water level in the pump well 46 throat. The sewage treatment plant control device 1 repeats the treatment for a plurality of future time points, and as a result, creates a control reference water level graph 63 on a coordinate plane having the horizontal axis as the time point and the vertical axis as the control reference water level. In the control reference water level graph 63, the portion at the past time point is the actual value drawn as it is. In FIG. 2, four time points (t ₁ , t ₂ , t ₃ , t ₄ ) are described as future time points, but the sewage treatment plant control device 1 sets the time points in more detail than these four time points. A delimited, smoother (continuous) control reference water level graph 63 may be drawn.

(Peak hold)
The sewage treatment plant control device 1 acquires the maximum value of the control reference water level graph 63 in the time window 65 having a predetermined time width. In FIG. 2, the control reference water level reaches the _{maximum value W p} at a time point approximately intermediate between the time _{point t 0} and the time point t _1. The sewage treatment control device 1, for all time points are included in the time window 65, the value of the control reference water level regarded as a maximum value W _p. That is, the sewage treatment plant control device 1 peak-holds the control reference water level at a certain representative value at the level of the horizon 64. This is a major feature of this embodiment. The fact that the past actual value of the control reference water level is required to determine the future discharge amount is due to the consideration of the time lag. If the accuracy of the discharge amount is not strictly required, the time window 65 may not include the past portion.

FIG. 3A is an example of the control reference water level information 31a when the sewage treatment plant control device 1 does not hold the peak. The control reference water level information 31a is a time series of combinations of time points and control reference water levels at the time points. The control reference water level is a variable value that changes with time. FIG. 3B is an example of the control reference water level information 31b when the sewage treatment plant control device 1 peak-holds. The control reference water level information 31b is also a time series of combinations of time points and control reference water levels at the time points. However, unlike FIG. 3B, the control reference water level is the maximum value W _p (invariant representative value) whose value is constant regardless of the change at the time point. The sewage treatment plant control device 1 of the present embodiment may output the control reference water level information 31a as shown in FIG. 3A (normal mode), and outputs the control reference water level information 31b as shown in FIG. 3B. It may be output (safety mode) (details will be described later).

W _p (invariant representative value) is not limited to the maximum value in the time window 65. For example, the sewage treatment plant control device 1 may use the smaller of the maximum value and the predetermined upper limit value as an invariant representative value, or multiply the maximum value by a predetermined ratio (for example, 90%). It may be an invariant representative value. That is, the invariant representative value may be a value large enough to satisfy a predetermined criterion.

(Second stage)
Return to FIG. The sewage treatment plant control device 1 refers to the discharge capacity information 33 in which the discharge amount for each pump (reference numerals 43 and 44) is stored, and the horizontal axis and the vertical axis (more accurately, the horizontal axis and the vertical axis) of the discharge amount matrix 32. Axis scale) is created (reference numeral 66). FIG. 4B is an example of the discharge amount matrix 32. Note that FIG. 4A will be described later. The horizontal axis of the discharge amount matrix 32 (column) is a sewage pump total discharge amount P _j. There are one or more sewage pumps 43. Now, the total discharge amount of these is called the total discharge amount of the sewage pump (kiloliter / minute). The vertical axis of the discharge amount matrix 32 (row) is a rainwater pump total discharge amount Q _i. There are one or more rainwater pumps 44. Now, the total discharge amount of these is called the total discharge amount of the rainwater pump (kiloliter / minute).

In FIG. 4B, the scales on the horizontal axis and the vertical axis have increments of 100 kiloliters / minute, but this is just an example, and other increments are used according to the content of the discharge capacity information 33. It may be a width, and the step size may not be uniform. In the second stage, the cell at the intersection of the vertical axis and the horizontal axis of the discharge amount matrix 32 remains blank.

(Third stage)
Return to FIG. The sewage treatment plant control device 1 refers to the risk database 34 and stores the risk at each intersection of the discharge amount matrix 32 (reference numeral 67). The risk database 34 is, for example, as shown in FIG. 4A, each in the coordinate space having the “control reference water level”, the “total discharge amount of the sewage pump” and the “total discharge amount of the rainwater pump” as three axes. A set of risks associated with a point. Risk has a three-dimensional vector type. The three elements of the vector are values indicating "inundation risk of sewage treatment area", "treatment failure risk of sewage treatment plant" and "pollution risk of public water area". These three elements are different from the values indicated by the three axes. The sewage treatment plant control device 1 may create a risk database 34 by accumulating past examples, or may create a risk database 34 by using a simulation device.

The sewage treatment plant control device 1 horizontally cuts the risk database 34 (FIG. 4 (a)) at the position of _{the control reference water level W p (maximum value) peak-held in the first stage.} Then, the sewage treatment plant control device 1 has elements of a three-dimensional vector associated with each point on the plane of the cut end 70 (“inundation risk of sewage treatment area”, “risk of poor treatment of sewage treatment plant” and “ Acquire the pollution risk of public water areas "). Further, in the sewage treatment plant control device 1, the horizontal axis and the vertical axis of the discharge amount matrix 32 created in the second stage are applied to the cut end 70, and the three elements acquired for the cells at the intersections of the horizontal axis and the vertical axis are obtained. Memorize the sum of.

As shown in FIG. 4B, the discharge amount matrix 32 created here is in a state in which the value of _{the risk Rij is stored in the cell at the intersection of the vertical axis and the horizontal axis.} Risk R _ij is rainwater pump total discharge amount is Q _i, and sewage pump total discharge amount is the risk of the entire water system when it is P _j. That is, as shown in FIG. 4C, the risk _Rij is the sum of the “inundation risk of the sewage treatment area”, the “treatment failure risk of the sewage treatment plant” and the “pollution risk of the public water area”. As mentioned above, these three types of risks are in a trade-off relationship with each other. The following can be seen by referring to the discharge amount matrix 32 (FIG. 4B).

-Now, as an example, focus on _{risks R 51} , R ₄₂ , R ₃₃ , R ₂₄ and R _15. All of these risks are risks when "Q _i + P _j = 600" is established. The actual values of risks R ₅₁ , R ₄₂ , R ₃₃ , R ₂₄ and R ₁₅ should be different for each. It cannot be said unconditionally which of these is the largest and which is the smallest.

-The "inundation risk of the sewage treatment area" which is one element of the risk R _{51 is described as "T (R 51} )", and the "inundation risk of the sewage treatment area" which is one element of the _{risk R 15 is "T (R 51)". 15} ) ”and compare the two. Then, "T (R ₅₁ ) ≒ T (R ₁₅ )" is established. This is because the inundation risk of any sewage treatment area corresponds to the total discharge amount of 600 (the upstream sewage treatment area is protected to the same extent).

-The "risk of poor treatment of the sewage treatment plant" which is one element of the risk R _{51 is described as "M (R 51} )", and the "risk of poor treatment of the sewage treatment plant" which is one element of the _{risk R 15 is "M".} (R ₁₅ ) ”and compare the two. Then, "M (R ₅₁ ) <M (R ₁₅ )" is established. Because sewage pump total discharge amount of processing defects risk sewage M (R ₁₅₎ is "500" (a large load on the sewage treatment plant 55). On the other hand, the total discharge amount of the sewage pump of the treatment failure risk M (R ₅₁ ) of the sewage treatment plant is only “100” (the burden on the sewage treatment plant 55 is small).

-The "public water pollution risk", which is one element of risk R _{51 , is written as "K (R 51} )", and the "public water pollution risk", which is one element of _{risk R 15 , is "K (R 15} )". ", And compare the two. Then, "K (R ₅₁ )> K (R ₁₅ )" is established. This is because the total discharge amount of the rainwater pump of the pollution risk K (R ₅₁ ) in the public water area is "500" (there is a lot of discharge to the public water area). In contrast, is from rainwater pump total discharge amount of pollution risk K (R ₁₅₎ of the public water is only "100" (discharged into public waters is small).

As is clear from the above, the respective values of "inundation risk of sewage treatment area", "treatment failure risk of sewage treatment plant" and "pollution risk of public water area", which are elements of _{risk Rij , are the values of risk Rij} . It changes depending on the position of the cell in the discharge amount matrix 32. Then, as a matter of course, _{the value of the risk Rij} as a whole also changes depending on the position of the cell in the discharge amount matrix 32.

In FIG. 4B, the risk _Rij is explained two-dimensionally. Now, the risk _{R 11} when the control reference water level in _{W 1 "R 11 (W 1} )" is denoted as the risk _{R 11} when the control reference water level in _{W 2 (W 1 <W 2} ) " It _{is written as "R 11} (W ₂ )" and the two are compared. It is clear that _{R 11} (W ₁ ) <R ₁₁ (W ₂ ) even if the total discharge amount (Q _i + P _j ) is the same “200”. This is because it is estimated that the “risk of poor treatment of sewage treatment plants” and the “risk of pollution of public water areas” (burden on the downstream side) are almost the same in both cases, while the control reference water level is W _2. This is because there is a greater risk that the sewage will flow back into the sewage treatment area 51.

This supports that the risk R _ij is _{a function F of Q i} , P _j and the control reference water level W. That is, "R _ij = F (W, Q _i , P _j )" is established. Although the explanations are slightly different, FIG. 4A illustrates this relationship. Incidentally, "δR / δW>0" also holds. The process of sewage treatment control device 1 is cut horizontally risk database 34 at the location of the control reference level W _p that peak hold is nothing but the process of sewage treatment control device 1 is "see" the control reference level ..

For example, the case where the control reference water level at the time point t _{3 is W 3} (FIG. 3 (a)) and the case where the control reference water level at the _{time point t 3 is W p} (FIG. 3 (b)) are compared. At this time, W ₃ <W _p . Therefore, the position where the sewage treatment plant control device 1 cuts the risk database 34 (FIG. 4 (a)) is higher in the case of FIG. 3 (b) than in the case of FIG. 3 (a). Then, the risk of the position of the intersection of the same vertical axis and horizontal axis of the discharge amount matrix 32 (FIG. 4 (b)) is greater in the case of FIG. 3 (b) than in the case of FIG. 3 (a). .. This can be achieved by cutting horizontally risk database 34 at the location of the control reference level W _p that peak hold, expected to risk the safety side (expected a greater risk) means that.

(4th stage)
Return to FIG. The sewage treatment plant control device 1 acquires a combination of the total discharge amount of the sewage pump and the total discharge amount of the rainwater pump that minimizes the risk (reference numeral 68). _{The sewage treatment plant control device 1 selects the risk R ij} of the discharge amount matrix 32 stored in the third stage, which has the smallest value (sum of three types of risks). Then, the sewage treatment plant control device 1 acquires a combination of the value of the total discharge amount of the sewage pump on the horizontal axis of the selected risk and the value of the total discharge amount of the rainwater pump on the vertical axis of the selected risk. An example of the combination acquired at this time is "(total discharge amount of sewage pump, total discharge amount of rainwater pump) = (200 kiloliters / minute, 400 kiloliters / minute)". The sewage treatment plant control device 1 will create such a combination at each future time point.

(5th stage)
The sewage treatment plant control device 1 allocates a start / stop time and a discharge amount for each of the rainwater pump and the sewage pump with reference to the pump allocation rule 35 (reference numeral 69). The sewage treatment plant control device 1 is individually operated so that the total discharge amount of the sewage pump is ●● kiloliters / minute for the period _{from the current time point t 0} to the latest future time point t _{4 included in the time window 65.} Create an operation plan for the sewage pump 43. At the same time, the sewage treatment plant control device 1 creates an operation plan for each rainwater pump 44 so that the total discharge amount of the rainwater pump is ◎◎ kiloliters / minute for the same period. The operation plan defines the on / off state (in the case of on, the instantaneous value of the discharge amount) for each pump (reference numerals 43 and 44) in chronological order. “●●” and “◎◎” abbreviate the total discharge amount of the sewage pump and the total discharge amount of the rainwater pump at each time point.

An example of pump allocation rule 35 is as follows.
-The sewage treatment plant control device 1 calculates the past operating rate (or the past cumulative operating time) for each sewage pump 43, and preferentially operates the sewage pump 43 from the one with the smallest operating rate (or the cumulative operating time). The same applies to the rainwater pump 44.
-When the sewage pump 43 has a variable discharge amount and a fixed discharge amount, the sewage treatment plant control device 1 preferentially operates the sewage pump 43 having a variable discharge amount. The same applies to the rainwater pump 44.
-The sewage treatment plant control device 1 does not restart the sewage pump 43 that has been continuously operated for more than a predetermined time from the time when the operation is stopped until the predetermined maintenance time elapses. The same applies to the rainwater pump 44.

(Configuration of sewage treatment plant control device)
The configuration of the sewage treatment plant control device 1 will be described with reference to FIG. The sewage treatment plant control device 1 is a general computer. The sewage treatment plant control device 1 includes a central control device 11, an input device 12, an output device 13, a main storage device 14, an auxiliary storage device 15, and a communication device 16. The auxiliary storage device 15 stores the control reference water level information 31, the discharge amount matrix 32, the discharge capacity information 33, the risk database 34, and the pump allocation rule 35. The simulation unit 21, the mode determination unit 22, the safety mode water level reference unit 23, and the normal mode water level reference unit 24 in the main storage device 14 are programs. In the following description, when the operating subject is described as "○○ part is", it is that the central control device 11 reads the ○○ part from the auxiliary storage device 15 and loads it into the main storage device 14, and then the ○○ part is described. It means to realize the function (detailed later).

As described above, the water level gauge 41, the flow meter 42, the sewage pump 43, and the rainwater pump 44 are arranged in the pumping station 3. The communication device 16 of the sewage treatment plant control device 1 can communicate with each of these via the network 2. The sewage pump 43 and the rainwater pump 44 are examples of "equipment used for draining sewage".

(Processing procedure)
The processing procedure will be described with reference to FIG.
In step S201, the simulation unit 21 of the sewage treatment plant treatment device 1 receives the internal measurement value 61 and the external measurement value 62. Specifically, first, the simulation unit 21 acquires the internal measurement value 61 from the water level gauge 41 and the flow meter 42 of the pumping station 3, and obtains the external measurement value 62 from any device outside the pumping station 3. get.
Secondly, the simulation unit 21 creates a control reference water level graph 63 (FIG. 2) based on the internal measurement value 61 and the external measurement value 62 received in the “first” of step S201. At this time, the simulation unit 21 sets the start point of the time window 65 as a time point that is advanced by a predetermined time from the present time, and the end point of the time window 65 as a time point that is advanced by a predetermined time from the present time.

In step S202, the mode determination unit 22 of the sewage treatment plant treatment device 1 determines the control mode. Specifically, first, the mode determination unit 22 determines the actual value of the water level of the pump well 46 at the present time and the actual value of the water level of the pump well 46 based on the internal measurement value 61 and the external measurement value 62 received in the “first” of step S201. , Acquire (calculate) the predicted value of the water level of the pump well 46 at a predetermined future time point.
Secondly, when at least one of the actual value of the water level and the predicted value of the water level acquired in the "first" of step S202 exceeds a predetermined threshold value, the mode determination unit 22 requires a "safety mode". Generate a "flag".

Thirdly, the mode determination unit 22 determines the actual value of the inflow to the pump well 46 at the present time and a predetermined value based on the internal measurement value 61 and the external measurement value 62 received in the “first” of step S201. Acquire (calculate) the predicted value of the inflow to the pump well 46 at a future point in time.
Fourth, the mode determination unit 22 is "safe" when at least one of the actual value of the inflow amount and the predicted value of the inflow amount acquired in "third" of step S202 exceeds a predetermined threshold value. Generate the mode required flag.

Fifth, the mode determination unit 22 "needs a safety mode" when the "safety mode necessary flag" is generated in at least one of the "second" or "fourth" of step S202. To decide. If the "safety mode required flag" is not generated in any of the "second" and "fourth" steps S202, the mode determination unit 22 does nothing.
When the "safety mode required flag" is generated in the "second" of step S202, the mode determination unit 22 may omit the "third" and "fourth" of step S202.

In step S203, the mode determination unit 22 determines whether or not the control mode is set to the safety mode. Specifically, the mode determination unit 22 proceeds to step S204 when it is determined in step S202 "fifth" that "safety mode is required" (step S203 "Yes"), and in other cases. (Step S203 “No”), the process proceeds to step S205.

In step S204, the safety mode water level reference unit 23 of the sewage treatment plant treatment device 1 outputs the peak-held reference water level. _{Specifically, the safety mode water level reference unit 23 obtains the maximum value W p} of the control reference water level in the time window 65 from the control reference water level graph 63 created in “second” of step S201, and obtains the obtained W _p . , The control reference water level for all time points included in the time window 65. Then, the safety mode water level reference unit 23 temporarily outputs (stores) the control reference water level information 31b as shown in FIG. 3B to the main storage device 14. The output control reference water level W _p is an “invariant representative value” that does not change depending on the time point. As described above, the "maximum value" here is only an example.

In step S205, the normal mode water level reference unit 24 of the sewage treatment plant treatment device 1 outputs a reference water level that does not hold a peak. Specifically, the normal mode water level reference unit 24 uses the control reference water level graph 63 created in “second” of step S201 as it is as the control reference water level information 31a as shown in FIG. 3A as the main storage device 14 Temporarily output (store) to. The output control reference water level W is a "variable value" that changes depending on the time point.

In step S206, the simulation unit 21 of the sewage treatment plant treatment device 1 reads out the discharge capacity information 33. Specifically, the simulation unit 21 reads out the discharge capacity information 33 in which the discharge capacity for each pump is stored from the auxiliary storage device 15.

In step S207, the simulation unit 21 creates the horizontal axis and the vertical axis of the discharge amount matrix 32. Specifically, the simulation unit 21 examines the discharge amount of each sewage pump 43 and the like. Now, it is assumed that there are five sewage pumps 43, all the sewage pumps 43 have no failure, and the discharge amount of all the sewage pumps 43 is "100 kiloliters / minute". At this time, the simulation unit 21 sets the scale on the horizontal axis of the discharge amount matrix 32 (FIG. 4B) to “100,200,300,400,500”. The same applies to the rainwater pump 44.

In step S208, the simulation unit 21 reads out the risk database 34. Specifically, first, the simulation unit 21 reads the risk database 34 from the auxiliary storage device 15. As described above, the risk database 34 has three axes, for example, "control reference water level", "total discharge amount of sewage pump", and "total discharge amount of rainwater pump" as shown in FIG. 4A. A set of three-dimensional vectors associated with each point in space. The three elements of the vector are values indicating "risk of inundation of sewage treatment area", "risk of poor treatment of sewage treatment plant" and "risk of pollution of public water area".

Second, the simulation unit 21 acquires the control reference water level at the time when the discharge amount is determined from the control reference water level information 31a (or 31b) temporarily stored in the main storage device 14. The discharge amount determination target time point is a time point at which the discharge amount of the sewage pump 43 and the discharge amount of the rainwater pump 44 at that time should be determined. In the present embodiment, it is assumed that the discharge amount determination target time points are t ₁ , t ₂ , t ₃ and t ₄ in FIG. 3 (a) (or FIG. 3 (b)).

When passing through step S204, the control reference water level acquired here is uniformly “W _p ” _{regardless of whether the discharge amount determination target time point is t 1} , t ₂ , t _{3 or} t _4. Yes (see FIG. 3 (b)). When passing through step S205, the control reference water level acquired here is “W _{1 ” when the discharge amount determination target time point is t 1} , and “W ₂ ” when the discharge amount determination target time point is t _2. And ..., "W ₄ " when the time point for determining the discharge amount is t _4.

In step S209, the simulation unit 21 acquires the risk from the risk database 34. Specifically, the simulation unit 21 cuts the risk database 34 on a horizontal plane including the control reference water level at the time when the discharge amount is determined (see FIG. 4A). Then, the simulation unit 21 acquires the sum of the three elements of the three-dimensional vector associated with each point of the cut 70 (risk _{Rij in} FIG. 4C).

In step S210, the simulation unit 21 stores the risk in the discharge amount matrix 32. Specifically, the simulation unit 21 applies the horizontal axis and the vertical axis created in step S207 to the risk acquired in step S209. Then, the discharge amount matrix 32 as shown in FIG. 4B is completed.

In step S211 the simulation unit 21 acquires a combination of discharge amounts that minimizes the risk. Specifically, the simulation unit 21 selects a cell at the intersection of the horizontal axis and the vertical axis of the discharge amount matrix 32, which has the minimum risk stored in the cell. Then, the simulation unit 21 acquires the total discharge amount of the sewage pump on the horizontal axis of the selected cell and the total discharge amount of the rainwater pump on the vertical axis of the selected cell.

The processes of steps S208 to S211 are repeated at each discharge amount determination target time point. At the stage when this iterative process is completed, the total discharge amount of the sewage pump and the total discharge amount of the rainwater pump are acquired at each _{time point for determining the discharge amount (t 1} , t ₂ , t ₃ and t _4). However, since the same result is obtained when passing through step S204 (safety mode), the processes of steps S208 to S211 may be executed only once.

In step S212, the simulation unit 21 reads out the pump allocation rule 35. Specifically, the simulation unit 21 reads the pump allocation rule 35 from the auxiliary storage device 15. As described above, the pump allocation rule 35 stores a rule for allocating the total discharge amount of the sewage (rainwater) pump as the total amount to each sewage (rainwater) pump.

In step S213, the simulation unit 21 determines the start / stop time and the discharge amount for each pump. Specifically, first, the simulation unit 21 creates a sewage pump operation plan. The sewage pump operation plan is the “on (departure)”, “off (stop)” and discharge amount of each sewage pump 43 at each discharge amount determination target time point (t ₁ , t ₂ , t ₃ and t _4). Is the information lined up.
Second, the simulation unit 21 creates a rainwater pump operation plan. The stormwater pump operation plan is information in which the “on”, “off”, and discharge amount of each rainwater pump 44 are arranged for each discharge amount determination target time point (t ₁ , t ₂ , t ₃ and t _4). ..

Third, the simulation unit 21 displays the sewage pump operation plan, the rainwater pump operation plan, and the control reference water level graph 63 on the screen of the output device 13. Further, the simulation unit 21 also displays on the screen whether the information displayed on the screen is caused by passing through step S204 (safety mode) or by passing through step S205 (normal mode).
After that, the processing procedure ends.

The processing procedure is executed at predetermined control cycles (for example, 5 minutes). Of course, it may be executed at any time according to the instruction of the user. The control cycle here is a different concept from the time width of the time window 65 and _{the interval between the discharge amount determination target time points (t 1} , t ₂ , t ₃ and t _4).

(Effect of this embodiment)
The effects of the sewage treatment plant control device of this embodiment are as follows.
(1) The sewage treatment plant control device can predict the water level of the pump well in the future period on the safe side (larger).
(2) The sewage treatment plant control device can determine the amount of sewage discharged from the pump well in the future period on the safe side.
(3) The sewage treatment plant control device can determine the discharge amount of sewage after comprehensively considering the risk on the upstream side and the risk on the downstream side of the pump well.

(4) The sewage treatment plant control device can handle cases where it is not necessary to stand on the safe side.
(5) The sewage treatment plant control device can determine whether or not it is necessary to stand on the safe side by using an objective threshold value.
(6) The sewage treatment plant control device can display the start / stop state of the pump, the time-series predicted value of the water level, and the like on the screen.

The present invention is not limited to the above-described embodiment, and includes various modifications. For example, the above-described embodiment has been described in detail in order to explain the present invention in an easy-to-understand manner, and is not necessarily limited to the one including all the configurations described. Further, it is possible to replace a part of the configuration of one embodiment with the configuration of another embodiment, and it is also possible to add the configuration of another embodiment to the configuration of one embodiment. Further, it is possible to add / delete / replace a part of the configuration of each embodiment with another configuration.

Further, each of the above-mentioned configurations, functions, processing units, processing means and the like may be realized by hardware by designing a part or all of them by, for example, an integrated circuit. Further, each of the above configurations, functions, and the like may be realized by software by the processor interpreting and executing a program that realizes each function. Information such as programs, tables, and files that realize each function can be placed in a memory, a hard disk, a recording device such as an SSD (Solid State Drive), or a recording medium such as an IC card, an SD card, or a DVD.
In addition, control lines and information lines are shown as necessary for explanation, and not all control lines and information lines are shown in the product. In practice, it can be considered that almost all configurations are interconnected.

1 Sewage treatment plant control device 2 Network 3 Pump station 11 Central control device 12 Input device 13 Output device 14 Main storage device 15 Auxiliary storage device 16 Communication device 21 Simulation unit 22 Mode judgment unit 23 Safety mode water level reference unit 24 Normal mode water level reference Part 31 Control reference Water level information 32 Discharge amount matrix 33 Discharge capacity information 34 Risk database 35 Pump allocation rule

Claims (5)

A simulation unit that predicts the water level of the sewage storage facility in chronological order over a future period,
A safety mode water level reference unit in which a value large enough to satisfy a predetermined standard among the predicted water levels is used as a representative value of the water level in the period.
A normal mode water level reference unit that sets a water level other than the representative value among the predicted water levels as a variable value of the water level during the period.
A mode determination unit that determines whether to select the safety mode water level reference unit or the normal mode water level reference unit, and
With
The representative value is
It is an invariant representative value whose value is constant during the above period.
The simulation unit
To determine the amount of sewage discharged from the sewage storage facility during the period based on the invariant representative value.
Emissions control device according to claim. The simulation unit
For the risk of inundation of the sewage treatment area located upstream of the sewage storage facility, the risk of poor treatment of the sewage treatment plant located downstream of the sewage storage facility, and the risk of pollution of the public water area located downstream of the sewage storage facility. To determine the emissions based on,
The emission control device according to claim 1. The mode determination unit
Determining whether to select the safety mode water level reference unit or the normal mode water level reference unit according to the magnitude relationship between the predicted value of the water level of the sewage storage facility and the predetermined threshold value.
2. The emission control device according to claim 2. The simulation unit
The start / stop status and discharge amount of the equipment used for discharging the sewage stored in the sewage storage equipment, and the water level are displayed on the screen in chronological order.
Displaying on the screen whether the safety mode water level reference unit or the normal mode water level reference unit is selected.
The emission control device according to claim 3. For the simulation unit of the emission control device
The process of predicting the water level of the sewage storage facility in chronological order in the future period is executed.
For the safety mode water level reference part of the discharge amount control device
A process is executed in which a value of the predicted water level that is large enough to satisfy a predetermined standard is used as a representative value of the water level in the period .
With respect to the normal mode water level reference part of the discharge amount control device
A process of setting a water level other than the representative value among the predicted water levels to a variable value of the water level in the period is executed.
For the mode determination unit of the emission control device,
A process of determining whether to select the safety mode water level reference unit or the normal mode water level reference unit is executed.
The representative value is
It is an invariant representative value whose value is constant during the above period.
For the simulation unit
To execute a process of determining the amount of sewage discharged from the sewage storage facility during the period based on the invariant representative value.
Emission control program for operating the emission control device.

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