Injection ratio control device and injection ratio control method

Abstract

To provide an injection ratio control device and an injection ratio control method, capable of controlling an injection ratio of an active carbon powder to be injected to target water to a proper value.SOLUTION: An injection ratio control device for controlling an injection ratio of an active carbon powder to target water includes: a time calculation part that calculates a first adsorption efficiency of an odor material contained in the target water by the active carbon powder based on at least one of a water temperature of the target water and an operation to the target water, and calculates an adsorption time in which adsorption of the odor material by the active carbon powder is performed by using the calculated first adsorption efficiency and a contact time of the active carbon powder and the odor material; and an injection ratio calculation part that calculates an injection ratio of the active carbon powder by using the calculated adsorption time.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to an injection rate control device and an injection rate control method. [Background technology]

[0002] In a water purification plant, for example, a water purification facility is provided that performs various operations on raw water (hereinafter also referred to as water to be treated) such as river water, well water, etc. Specifically, in such a water purification facility, for example, an operation is performed to remove odorous substances contained in the water to be treated by injecting (adding) powdered activated carbon into the water to be treated (see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2005-288309 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the water purification facility as described above, it is desirable to control, for example, the injection rate of powdered activated carbon injected into the water to be treated to an appropriate value. [Means for solving the problem]

[0005] The injection rate control device according to the present disclosure is an injection rate control device that controls the injection rate of powdered activated carbon into water to be treated, and includes: a time calculation unit that calculates a first adsorption efficiency of odorous substances contained in the water to be treated by the powdered activated carbon based on at least one of a temperature of the water to be treated and an operation on the water to be treated, and calculates an adsorption time during which the odorous substances are adsorbed by the powdered activated carbon using the calculated first adsorption efficiency and a contact time between the powdered activated carbon and the odorous substances; and an injection rate calculation unit that calculates the injection rate of the powdered activated carbon using the calculated adsorption time. Effect of the Invention

[0006] According to the injection rate control device and injection rate control method of the present disclosure, it is possible to appropriately control the injection rate of powdered activated carbon injected into the water to be treated. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a diagram illustrating a configuration diagram of a water treatment system 100 according to the first embodiment. [Diagram 2] FIG. 2 is a diagram illustrating the hardware configuration of the control device 10. As shown in FIG. [Diagram 3] FIG. 3 is a flow chart illustrating the injection rate control process in the first embodiment. [Figure 4] FIG. 4 is a diagram for explaining a specific example of the kinematic viscosity information 131. As shown in FIG. [Diagram 5] FIG. 5 is a diagram illustrating a specific example of the operational efficiency information 132. As shown in FIG. [Figure 6] FIG. 6 is a diagram for explaining a specific example of the equipment capacity information 133. As shown in FIG. [Figure 7] FIG. 7 is a diagram showing an experimental result in the first embodiment. [Figure 8] FIG. 8 is a diagram showing an experimental result in the first embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. However, such descriptions should not be interpreted in a limiting sense and do not limit the subject matter described in the claims. In addition, various changes, substitutions, and modifications can be made without departing from the spirit and scope of the present disclosure. In addition, different embodiments can be appropriately combined.

[0009] [Water treatment system 100 according to the first embodiment] First, a configuration example of the water treatment system 100 in the first embodiment will be described. Fig. 1 is a diagram for explaining the configuration diagram of the water treatment system 100 in the first embodiment. Note that the positions and numbers of pumps and lines (pipes) in the following example are merely examples and are not limited to these.

[0010] The water treatment system 100 is, for example, a water purification system installed in a water supply plant.

[0011] Specifically, the water treatment system 100 includes, for example, a contact basin 1 (hereinafter also referred to as activated carbon contact basin 1), a mixing basin 2 (hereinafter also referred to as chemical mixing basin 2), a flocculation basin 3, a control device 10 (hereinafter also referred to as injection rate control device 10), a pump P1, a pump P2, a pump P3, a pump P11, and a pump P12.

[0012] The pump P1 is disposed, for example, in a line L1 that connects a receiving well (not shown) and the contacting basin 1. The pump P1 supplies the water to be treated from the receiving well to the contacting basin 1 in accordance with, for example, a pre-specified amount and a pre-specified time interval.

[0013] The pump P11 is disposed, for example, in a line L11 that connects a storage vessel 4 that stores powdered activated carbon to the contactor basin 1. The pump P11 supplies the powdered activated carbon stored in the storage vessel 4 to the contactor basin 1 in a predetermined amount and at a predetermined time interval, thereby injecting the powdered activated carbon into the water to be treated stored in the contactor basin 1. Note that, although the following description will be given of a case in which the powdered activated carbon is injected into the water to be treated in the contactor basin 1, the present invention is not limited to this. Specifically, the powdered activated carbon may be injected into the water to be treated in equipment (for example, the line L1) upstream of the contactor basin 1.

[0014] Contact basin 1, for example, brings the water to be treated supplied via line L1 into contact with powdered activated carbon supplied via line L11. Then, contact basin 1 supplies the water to be treated after contact with the powdered activated carbon to mixing basin 2 via line L2 that connects contact basin 1 and mixing basin 2.

[0015] The pump P2 is disposed, for example, in the line L2, and supplies the water to be treated (the water to be treated after being contacted with the powdered activated carbon in the contact basin 1) from the contact basin 1 to the mixing basin 2, for example, in a predetermined amount and at a predetermined time interval.

[0016] The pump P12 is disposed, for example, in a line L12 that connects the mixing basin 2 to a storage tank 5 that stores a flocculant. The pump P12 supplies the flocculant stored in the storage tank 5 to the mixing basin 2 in a predetermined amount and at a predetermined time interval, thereby injecting the flocculant into the water to be treated stored in the mixing basin 2. Note that, although the following description is of a case in which the flocculant is injected into the water to be treated in the mixing basin 2, this is not limiting. Specifically, the flocculant may be injected into the water to be treated in a facility (for example, line L2) upstream of the mixing basin 2.

[0017] The mixing basin 2, for example, agitates the water to be treated supplied via line L2 and a flocculant supplied via line L12. Then, the mixing basin 2 supplies the water to be treated after stirring to the flocculation basin 3 via line L3 that connects the mixing basin 2 and the flocculation basin 3.

[0018] The pump P3 is disposed, for example, in the line L3, and supplies the water to be treated (the water to be treated after being mixed in the mixing basin 2) from the mixing basin 2 to the flocculation basin 3, for example, in a pre-specified amount and at pre-specified time intervals.

[0019] The flocculation basin 3 forms flocs by flocculating suspended solids contained in the water to be treated supplied via, for example, a line L3. The flocculation basin 3 supplies the water to be treated after flocculation to a downstream facility via, for example, a line L4 connecting the flocculation basin 3 with the downstream facility (for example, a sedimentation basin in which flocs are separated from the water to be treated by settling them).

[0020] In the above example, the contact basin 1, mixing basin 2, and other facilities are connected by lines, and the treated water is transported between the facilities by pumps installed on the lines, but the present invention is not limited to this. Specifically, the treated water may be transported between the facilities by a gravity flow method or the like that does not use lines or pumps.

[0021] The control device 10 performs a process (hereinafter also referred to as an injection rate control process) for controlling the injection rate of powdered activated carbon to the water to be treated stored in the contact basin 1 (the amount injected per unit amount of the water to be treated).

[0022] That is, the control device 10 controls the amount of powdered activated carbon supplied from the storage vessel 4 to the contact pond 1 by controlling the pump P11, for example.

[0023] Specifically, the control device 10 in this embodiment calculates the adsorption efficiency (hereinafter also simply referred to as the adsorption efficiency or the first adsorption efficiency) of odorous substances contained in the water to be treated by the powdered activated carbon based on, for example, the temperature of the water to be treated (for example, the temperature of the water to be treated in the contact basin 1). The control device 10 then calculates the substantial adsorption time (hereinafter also simply referred to as the adsorption time) during which the odorous substances are adsorbed by the powdered activated carbon, for example, by using the calculated first adsorption efficiency and the contact time between the powdered activated carbon and the odorous substances (hereinafter also simply referred to as the contact time). The control device 10 then calculates the amount of powdered activated carbon to be injected by the pump P11, for example, by using the calculated adsorption time.

[0024] That is, the inventors have found that, for example, the temperature of the water to be treated flowing into the water treatment system 100 affects the adsorption efficiency (adsorption speed) of odorants by powdered activated carbon, but does not affect the adsorption capacity of odorants by powdered activated carbon. In other words, the inventors have found that, for example, when calculating the injection rate of powdered activated carbon using the temperature of the water to be treated, it is possible to calculate the injection rate of powdered activated carbon without considering the effect on the adsorption capacity of odorants by powdered activated carbon, as long as the effect on the adsorption efficiency of odorants by powdered activated carbon is taken into account.

[0025] Therefore, the control device 10 in this embodiment calculates the adsorption time as the time required to adsorb the same amount of odorous substances as the odorous substances adsorbed within the contact time under standard conditions, for example, by using the first adsorption efficiency corresponding to the temperature of the water to be treated. The standard conditions here are, for example, conditions in which the temperature of the water to be treated is 20°C. Then, the control device 10 calculates the injection rate of powdered activated carbon to the water to be treated, for example, by using the calculated adsorption time.

[0026] This enables the control device 10 in this embodiment to, for example, appropriately control the injection rate of powdered activated carbon injected into the water to be treated. In other words, the control device 10 can, for example, prevent excessive injection of powdered activated carbon into the water to be treated. Therefore, the control device 10 can, for example, reduce the cost required for operating the water treatment system 100. In addition, the control device 10 can, for example, prevent the occurrence of a situation in which the amount of powdered activated carbon injected into the water to be treated is insufficient. Therefore, the control device 10 can, for example, stabilize the operation of the water treatment system 100.

[0027] Furthermore, the present inventors have found that it is possible to calculate (estimate) the adsorption efficiency of odorous substances by powdered activated carbon by using a physical property value, for example, the kinetic viscosity of the water to be treated.

[0028] Therefore, the control device 10 in the present embodiment, for example, specifies the kinetic viscosity of the water to be treated corresponding to the water temperature of the water to be treated (hereinafter, also simply referred to as kinetic viscosity). Then, the control device 10 calculates the first adsorption efficiency by using, for example, the specified kinetic viscosity.

[0029] Furthermore, the present inventors have found that, for example, the adsorption efficiency (adsorption speed) of odorous substances varies depending on the type of operation performed on the water to be treated in the water treatment system 100.

[0030] Therefore, the control device 10 in this embodiment calculates, for example, for one or more operations (hereinafter simply referred to as one or more operations) in which the powdered activated carbon comes into contact with odorous substances among a plurality of operations on the water to be treated, the contact time during which each operation is performed (hereinafter also referred to as the first contact time). Then, for example, for one or more operations, the control device 10 calculates the adsorption time during which each operation is performed (hereinafter also referred to as the first adsorption time) from the first contact time corresponding to each operation by using the adsorption efficiency of the odorous substances by the powdered activated carbon during which each operation is performed (hereinafter simply referred to as the adsorption efficiency or the second adsorption efficiency). Specifically, for example, the control device 10 calculates, for one or more operations, the time required to adsorb the same amount of odorous substances as those adsorbed within the first contact time corresponding to each operation under standard conditions as the first adsorption time. The standard conditions here are, for example, a situation in which no coagulant is injected into the water to be treated. Thereafter, the control device 10 calculates the adsorption time of the odorous substances by the powdered activated carbon (the adsorption time in the entire water treatment system 100) by using, for example, the total time (hereinafter also simply referred to as the total time) of the first adsorption times corresponding to each of the one or more operations.

[0031] In the following description, the operation in the contact basin 1, the operation in the mixing basin 2, and the operation in the flocculation basin 3 are each assumed to be one or more operations in which the powdered activated carbon comes into contact with odorous substances, but are not limited to this. Specifically, the one or more operations in which the powdered activated carbon comes into contact with odorous substances may include, for example, an operation in a facility other than the contact basin 1, the mixing basin 2, and the flocculation basin 3 (for example, an operation in a settling basin which is a facility downstream of the flocculation basin 3).

[0032] Furthermore, the inventors have found that, for example, the water quality of the water to be treated flowing into the water treatment system 100 affects the odorant adsorption capacity of the powdered activated carbon, but does not affect the odorant adsorption efficiency (adsorption rate) of the powdered activated carbon. The water quality of the water to be treated here is, for example, the degree of influence of the presence of soluble organic matter (competitive adsorption components constituting the soluble organic matter) contained in the water to be treated on the adsorption of odorants by the powdered activated carbon (hereinafter also referred to as water quality influence). In other words, the inventors have found that, for example, when calculating the injection rate of powdered activated carbon using the water quality of the water to be treated, if the influence on the odorant adsorption capacity of the powdered activated carbon is taken into account, the injection rate of powdered activated carbon can be calculated without taking into account the influence on the odorant adsorption efficiency of the powdered activated carbon.

[0033] Furthermore, the inventors have found that, for example, while it is difficult to identify the many types of competitive adsorption components contained in the water to be treated and to specify the water quality impact of each component, it is possible to calculate (estimate) the water quality impact of all the competitive adsorption components contained in the water to be treated by assuming that the types of competitive adsorption components contained in the water to be treated are approximately several types. Specifically, the inventors have found that, for example, by classifying soluble organic matter contained in the water to be treated into multiple components (hereinafter also referred to as multiple groups) based on the ultraviolet absorbance (SUVA: Specific UltraViolet Absorbance) in the water to be treated and regarding each of the multiple classified components as one type of pseudo competitive adsorption component, it is possible to calculate the water quality impact of all the competitive adsorption components contained in the water to be treated.

[0034] Therefore, the control device 10 in this embodiment classifies the soluble organic matter contained in the water to be treated into a plurality of components, and calculates water quality information (hereinafter also simply referred to as water quality information) indicating the water quality of the water to be treated (for example, the water quality effect due to the total of competitively adsorbed components contained in the water to be treated) using the concentration of the soluble organic matter (DOC: Dissolved Organic Carbon) for each of the plurality of classified components. Specifically, the control device 10 classifies the soluble organic matter in the water to be treated into a plurality of components, for example, by using the ultraviolet absorbance of the soluble organic matter contained in the water to be treated. Then, the control device 10 calculates the injection rate of powdered activated carbon by using the calculated water quality information in addition to the adsorption time of odorous substances by powdered activated carbon, for example.

[0035] This enables the control device 10 in this embodiment to more accurately control, for example, the injection rate of powdered activated carbon injected into the water to be treated.

[0036] [Control device 10 in the first embodiment] Next, the configuration of the control device 10 in the first embodiment will be described. FIG 2 is a diagram illustrating the hardware configuration of the control device 10.

[0037] The control device 10 is, for example, an electronic device having an electronic circuit. Specifically, as shown in Fig. 2, the control device 10 is, for example, a computer device having a processor, a CPU 101, a memory 102, a communication device 103, and a storage medium 104. Each part is connected to each other, for example, via a bus 105.

[0038] The storage medium 104 has, for example, a program storage area (not shown) that stores a program 110 for performing the injection rate control process. The storage medium 104 also has, for example, an information storage area 130 that stores information used when performing the injection rate control process. The storage medium 104 may be, for example, a hard disk drive (HDD) or a solid state drive (SSD).

[0039] The CPU 101 performs the injection rate control process by, for example, executing a program 110 loaded from the storage medium 104 to the memory 102 .

[0040] The communication device 103 accesses the pump P11, an operation terminal (not shown) through which an operator inputs necessary information, and the like, via a network (not shown) such as the Internet, for example.

[0041] The control device 10 may include, for example, a field programmable gate array (FPGA) or an application specific integrated circuit (ASIC). The injection rate control process may be executed in, for example, the FPGA or the ASIC.

[0042] In addition, although the following description will be given of a case where the water treatment system 100 has one control device 10, the water treatment system 100 may have, for example, a plurality of control devices 10. And, the injection rate control process may be performed, for example, in a distributed manner among the plurality of control devices 10.

[0043] Furthermore, hereinafter, among the functions by which the control device 10 realizes the injection rate control process, the function of calculating the adsorption time of odorous substances by powdered activated carbon will be referred to as a time calculation unit, the function of calculating water quality information of the water to be treated will be referred to as a water quality calculation unit, and the function of calculating the injection rate of powdered activated carbon will be referred to as an injection rate calculation unit.

[0044] [Injection rate control process in the first embodiment] Next, the injection rate control process in the first embodiment will be described. Fig. 3 is a flow chart for explaining the injection rate control process in the first embodiment. Figs. 4 to 8 are diagrams for explaining the injection rate control process in the first embodiment. Hereinafter, the injection rate control process performed when 2-Methylisoborneol (2-MIB) contained in the water to be treated is the substance to be removed (hereinafter, also simply referred to as the target substance) will be described.

[0045] The control device 10 determines a first adsorption efficiency of the powdered activated carbon for the odorous substances contained in the water to be treated, based on, for example, the temperature of the water to be treated (step S1 in FIG. 3).

[0046] Specifically, the control device 10 acquires the temperature of the water to be treated from, for example, a thermometer (not shown) that measures the temperature of the water to be treated flowing through the line L1. Then, the control device 10 identifies the kinetic viscosity of the water to be treated that corresponds to the acquired water temperature, for example, by referring to the kinetic viscosity information 131 stored in the information storage area 130. Thereafter, the control device 10 calculates the first adsorption efficiency by, for example, using the identified kinetic viscosity.

[0047] More specifically, the control device 10 calculates the first adsorption efficiency by, for example, using a value obtained by dividing the kinetic viscosity of the water to be treated corresponding to a predetermined water temperature by the kinetic viscosity of the water to be treated corresponding to the water temperature obtained from a thermometer. That is, the control device 10 calculates the first adsorption efficiency by, for example, using the following formula 1. Note that the following description will be given assuming that the predetermined temperature is 20 (°C).

[0048]

number

[0049] In the above formula 1, T represents the water temperature of the water to be treated (the water temperature of the water to be treated obtained from a thermometer), and K T represents the first adsorption efficiency when the water temperature of the water to be treated is T, and v 20℃indicates the kinetic viscosity of the water to be treated when the water temperature is 20 (℃), and ν T indicates the kinetic viscosity of the water to be treated when the water temperature is T. A specific example of the kinetic viscosity information 131 will be described below.

[0050] [Specific example of kinematic viscosity information 131] FIG. 4 is a diagram for explaining a specific example of the kinematic viscosity information 131. As shown in FIG.

[0051] The kinetic viscosity information 131 shown in FIG. 4 includes, for example, items of "water temperature" in which each water temperature is set, and "kinetic viscosity" in which a kinetic viscosity corresponding to each water temperature is set.

[0052] Specifically, in the information on the first line of the kinetic viscosity information 131 shown in FIG. 4, for example, “water temperature” is set to “0 (° C.)” and “kinetic viscosity” is set to “1.793 (mm 2 / s)" is set.

[0053] In addition, in the information on the second line of the kinetic viscosity information 131 shown in FIG. 4, for example, “5 (° C.)” is set as the “water temperature” and “1.521 (mm 2 / s)" is set.

[0054] In addition, in the information on the fifth line of the kinetic viscosity information 131 shown in FIG. 4, for example, “20 (° C.)” is set as the “water temperature” and “1.004 (mm 2 / s)" is set. Other information contained in Figure 4 is omitted.

[0055] Therefore, for example, when the temperature of the water to be treated is 5 (°C), the control device 10 calculates a kinetic viscosity of 1.004 (mm 2 / s) is the kinematic viscosity of 1.521 (mm 2 / s) to calculate a first adsorption efficiency of 0.660.

[0056] Returning to FIG. 3, the control device 10 calculates, for example, for one or more operations in which the powdered activated carbon comes into contact with odorous substances among a plurality of operations on the water to be treated, the second adsorption efficiency of odorous substances by the powdered activated carbon corresponding to each operation (step S2 in FIG. 3).

[0057] Specifically, the control device 10 calculates the second pick-up efficiency corresponding to each operation, for example, by referring to the operation efficiency information 132 stored in the information storage area 130. A specific example of the operation efficiency information 132 will be described below.

[0058] [Specific example of operational efficiency information 132] FIG. 5 is a diagram illustrating a specific example of the operational efficiency information 132. As shown in FIG.

[0059] The operational efficiency information 132 shown in FIG. 5 includes, for example, items such as a "contacting basin" in which a second adsorption efficiency corresponding to contacting basin 1 is set, a "mixing basin" in which a second adsorption efficiency corresponding to mixing basin 2 is set, and a "flocculation basin" in which a second adsorption efficiency corresponding to flocculation basin 3 is set.

[0060] Specifically, in the operational efficiency information 132 shown in FIG. 5, the information corresponding to "2-MIB" is set, for example, as the "contact basin" to "1.0", as the "mixing basin" to "1.0", and as the "flocculation basin" to "0".

[0061] In the operational efficiency information 132 shown in FIG. 5, the information corresponding to "Geosmin" is set, for example, as the "contact basin" to "1.0," as the "mixing basin," to "0.5," and as the "flocculation basin" to "0."

[0062] Therefore, for example, when the injection rate of powdered activated carbon required for adsorption and removal of 2-MIB contained in the water to be treated is calculated, the control device 10 specifies 1.0 as the second adsorption efficiency corresponding to the contact basin 1, specifies 1.0 as the second adsorption efficiency corresponding to the mixing basin 2, and specifies 0 as the second adsorption efficiency corresponding to the flocculation basin 3.

[0063] Each of the second adsorption efficiencies set in the operational efficiency information 132 may be calculated using, for example, the adsorption speed of odorous substances in each piece of equipment.

[0064] Returning to FIG. 3, the control device 10 calculates, for example, by using the second adsorption efficiency calculated in step S2, a first contact time during each operation in which the powdered activated carbon comes into contact with odorous substances among the multiple operations on the water to be treated (step S3 in FIG. 3).

[0065] Specifically, the control device 10 acquires the flow rate of the water to be treated from, for example, a flow meter (not shown) that measures the flow rate of the water to be treated flowing through the line L1. The control device 10 also identifies, for each of the one or more operations, the capacity of the equipment in which each operation is performed, for example, by referring to the equipment capacity information 133 stored in the information storage area 130. The control device 10 then identifies, for each of the one or more operations, the first contact time during which each operation is performed, for example, from the acquired flow rate of the water to be treated and the capacity of the equipment identified for each operation. Specific examples of the equipment capacity information 133 will be described below.

[0066] [Example of facility capacity information 133] FIG. 6 is a diagram for explaining a specific example of the equipment capacity information 133. As shown in FIG.

[0067] The facility capacity information 133 shown in FIG. 6 includes, for example, items such as "contacting basin" in which the capacity of contacting basin 1 is set, "mixing basin" in which the capacity of mixing basin 2 is set, and "flocculation basin" in which the capacity of flocculation basin 3 is set.

[0068] Specifically, the facility capacity information 133 shown in FIG. 6 includes, for example, “200 (m 3 )" is set as the "mixing pond" and "50 (m 3 ) is set as the "flocculation pond" and "600 (m 3 )" is set.

[0069] Therefore, for example, if the flow rate measured by a flow meter is 10(m 3 / min), the control device 10 controls the contactor 1 to have a capacity of 200 (m 3 ) to 10(m 3 / min) to calculate 20 (min) as the first contact time during operation in contact basin 1.

[0070] In this case, the control device 10 also calculates, for example, a capacity of 50 (m 3 ) to 10(m 3 / min) to calculate 5 (min) as the first contact time during operation in mixing basin 2.

[0071] Furthermore, the control device 10 may, in this case, calculate the volume of the flocculation basin 3, for example, 600 (m 3 ) to 10(m 3 / min) to calculate 60 (min) as the first contact time during operation in flocculation basin 3.

[0072] Returning to FIG. 3, the control device 10 calculates the adsorption time of odorous substances by the powdered activated carbon (adsorption time in the entire water treatment system 100) from, for example, the first adsorption efficiency calculated in step S1, the second adsorption efficiency calculated in step S2, and the first contact time calculated in step S3 (step S4 in FIG. 3).

[0073] Specifically, for example, for each of the one or more operations, the control device 10 calculates a first adsorption time during which each operation is performed from a second adsorption efficiency corresponding to each operation and a first contact time corresponding to each operation. Then, the control device 10 calculates an adsorption time for the entire water treatment system 100 from, for example, the first adsorption efficiency calculated in step S1 and the total time of the first adsorption times corresponding to each of the one or more operations.

[0074] More specifically, the control device 10 calculates, for example, for each of one or more operations, the product of the second adsorption efficiency corresponding to each operation and the first contact time corresponding to each operation as the first adsorption time corresponding to each operation. Then, the control device 10 calculates, for example, the product of the total time of the first adsorption times corresponding to each of the one or more operations and the first adsorption efficiency as the adsorption time for the entire water treatment system 100. That is, the control device 10 calculates the adsorption time for the entire water treatment system 100 by using, for example, the following formula 2.

[0075]

number

[0076] In the above formula 2, t st represents the adsorption time in the entire water treatment system 100, i represents each operation, and K i indicates the second adsorption efficiency corresponding to each operation, and t i indicates the first contact time corresponding to each operation, and K i t i indicates the first adsorption time corresponding to each operation, and ΣK i t i indicates the total time of the first adsorption time corresponding to each operation.

[0077] Specifically, the operational efficiency information 132 shown in FIG. 5 indicates that, for example, among the second adsorption efficiencies corresponding to 2-MIB, the second adsorption efficiency corresponding to the contact basin 1 is 1.0, the second adsorption efficiency corresponding to the mixing basin 2 is 1.0, and the second adsorption efficiency corresponding to the flocculation basin 3 is 0.

[0078] Therefore, for example, if the first contact time corresponding to contact pond 1 is 20 (minutes), the control device 10 calculates 20 (minutes) by multiplying the second adsorption time corresponding to contact pond 1, which is 1.0, by the first contact time corresponding to contact pond 1, which is 20 (minutes), and identifies the calculated 20 (minutes) as the first adsorption time corresponding to contact pond 1.

[0079] Also, for example, if the first contact time corresponding to mixing basin 2 is 5 (minutes), the control device 10 calculates 5 (minutes) by multiplying the second adsorption time corresponding to mixing basin 2, which is 1.0, by the first contact time corresponding to mixing basin 2, which is 5 (minutes), and identifies the calculated 5 (minutes) as the first adsorption time corresponding to mixing basin 2.

[0080] Furthermore, for example, when the first contact time corresponding to the flocculation basin 3 is 60 (minutes), the control device 10 calculates 0 (minutes) by multiplying the second adsorption time corresponding to the flocculation basin 3, 0, by the first contact time corresponding to the flocculation basin 3, 60 (minutes), and identifies the calculated 0 (minutes) as the first adsorption time corresponding to the flocculation basin 3.

[0081] Then, the control device 10 calculates 25 (minutes) by adding, for example, the first adsorption time corresponding to contact basin 1, which is 20 (minutes), the first adsorption time corresponding to mixing basin 2, which is 5 (minutes), and the first adsorption time corresponding to flocculation basin 3, which is 0 (minutes), and specifies the calculated 25 (minutes) as the total time of the first adsorption times corresponding to contact basin 1, mixing basin 2, and flocculation basin 3.

[0082] Then, for example, when the first adsorption efficiency is 0.660 (when the water temperature of the water to be treated is 5 (°C)), the control device 10 multiplies the first adsorption efficiency of 0.660 by the total first adsorption time of 25 (minutes) to calculate 16.5 (minutes), and calculates the calculated 16.5 (minutes) as the adsorption time for the entire water treatment system 100.

[0083] Returning to Figure 3, the control device 10, for example, classifies the soluble organic matter contained in the water to be treated into multiple components and calculates water quality information indicating the water quality of the water to be treated using the concentration of the soluble organic matter for each of the multiple classified components (step S5 in Figure 3).

[0084] Specifically, the control device 10 classifies the soluble organic matter in the water to be treated into a plurality of components, for example, by using the ultraviolet absorbance of the soluble organic matter contained in the water to be treated. Then, the control device 10 calculates water quality information indicating the water quality of the water to be treated, for example, by using the concentration of the soluble organic matter for each of the plurality of classified components. That is, the control device 10 calculates the water quality information, for example, by using the following formula 3.

[0085]

number

[0086] In the above formula 3, f w indicates the water quality information of the treated water, and DOC water indicates the concentration of dissolved organic carbon in the treated water, and SUVA water indicates the ultraviolet absorbance per unit dissolved organic carbon concentration in the treated water, and SUVA max indicates the theoretical maximum UV absorbance per unit dissolved organic carbon concentration in the treated water, and A 1 and A 2 Each of the following indicates the coefficient. max may be, for example, the SUVA value when only corroded substances (such as humic substances) are dissolved.

[0087] That is, the control device 10 considers that the soluble organic matter contained in the water to be treated is composed of two types of organic matter that has ultraviolet light absorption properties (hereinafter also referred to as first pseudo organic matter) and organic matter that does not have ultraviolet light absorption properties (hereinafter also referred to as second pseudo organic matter).The control device 10 then calculates, as water quality information for the water to be treated, the sum of a value calculated by multiplying the concentration of the first pseudo organic matter contained in the water to be treated by a coefficient and a value calculated by multiplying the concentration of the second pseudo organic matter contained in the water to be treated by a coefficient.

[0088] As a result, the control device 10 in this embodiment is able to calculate water quality information for the treated water even when, for example, it is not possible to identify each of the many types of competitive adsorption components contained in the treated water.

[0089] Returning to FIG. 3, the control device 10 acquires, for example, the particle size of the powdered activated carbon supplied to the water to be treated via the line L11 (step S6 in FIG. 3).

[0090] Then, the control device 10 calculates the injection rate of powdered activated carbon to the water to be treated, for example, by using the adsorption time calculated in step S4, the water quality information calculated in step S5, and the particle size acquired in step S6 (step S7 in FIG. 3).

[0091] Specifically, the injection rate of powdered activated carbon to the water to be treated is calculated using the following formulas 4 to 8.

[0092]

number

[0093]

number

[0094]

number

[0095]

number

[0096]

number

[0097] In the above formulas 4 to 8, G(fw) represents a function for correcting the effect of the competitive adsorption component fw in activated carbon adsorption (hereinafter, also referred to as the correction function for fw), q represents the adsorption efficiency of odorous substances by powdered activated carbon, and C 0 indicates the initial concentration of the target substance in the water to be treated (the concentration of the water to be treated before each operation is performed in the water treatment system 100), and C i indicates the target concentration of the target substance in the water to be treated (the target concentration of the target substance after each operation is performed in the water treatment system 100), and C C indicates the injection rate of powdered activated carbon, d50 indicates the particle size of powdered activated carbon, K, n, A 3 , A 4 , A 5 , A 6 , A 7 , A 8 , A 9 and A 10 Each of these indicates a respective coefficient.

[0098] Returning to FIG. 3, the control device 10 controls the pump P11 so that the powdered activated carbon is injected according to the injection rate calculated in step S7 (step S8 in FIG. 3).

[0099] For example, when there are multiple target substances, the control device 10 may perform steps S2 to S7 for each of the multiple target substances. Then, the control device 10 may perform step S8 (control of the pump P11) by following the maximum injection rate calculated in step S7 for each of the multiple target substances.

[0100] In this manner, the control device 10 in this embodiment calculates the first adsorption efficiency of odorous substances by the powdered activated carbon based on, for example, at least one of the temperature of the water to be treated and the operation on the water to be treated. The control device 10 then calculates the adsorption time during which the odorous substances are adsorbed by the powdered activated carbon, for example, by using the calculated first adsorption efficiency and the contact time between the powdered activated carbon and the odorous substances. Thereafter, the control device 10 calculates the injection rate of the powdered activated carbon, for example, by using the calculated adsorption time.

[0101] Specifically, the control device 10, for example, specifies the kinetic viscosity of the water to be treated corresponding to the water temperature, and calculates the first adsorption efficiency by using the specified kinetic viscosity.

[0102] Furthermore, the control device 10 calculates, for example, a first contact time, which is the contact time during which each operation is performed, for one or more operations in which the powdered activated carbon comes into contact with odorous substances among a plurality of operations performed on the water to be treated. Then, for example, for one or more operations, the control device 10 calculates a first adsorption time, which is the adsorption time during which each operation is performed, from the first contact time corresponding to each operation, by using the second adsorption efficiency of odorous substances by the powdered activated carbon during each operation. After that, the control device 10 calculates the adsorption time for the entire water treatment system 100, for example, by using the total time of the first adsorption times corresponding to each of the one or more operations.

[0103] In addition, the control device 10, for example, classifies the soluble organic matter contained in the water to be treated into a plurality of components, and calculates water quality information indicating the water quality of the water to be treated using the concentration of the soluble organic matter for each of the plurality of classified components.

[0104] The controller 10 also calculates the injection rate of the powdered activated carbon, for example, by using the particle size of the powdered activated carbon.

[0105] This allows the control device 10 in this embodiment to, for example, appropriately control the injection rate of powdered activated carbon injected into the water to be treated. In other words, the control device 10 can, for example, prevent excessive injection of powdered activated carbon into the water to be treated. Therefore, the control device 10 can, for example, reduce the cost required to operate the water treatment system 100.

[0106] In the above example, the control device 10 calculates the water quality information of the water to be treated by using the ultraviolet absorbance, but the present invention is not limited to this. Specifically, the control device 10 may calculate the water quality information by performing, for example, size exclusion chromatography (SEC).

[0107] More specifically, in this case, the control device 10 may fractionate the soluble organic matter contained in the water to be treated into a plurality of components, for example, by performing size exclusion chromatography. The control device 10 may then calculate, for each of the plurality of components, the product of the amount of each component measured by a measuring device (not shown) and a coefficient corresponding to each component. After that, the control device 10 may calculate, for example, the sum of the products calculated for each of the plurality of components as the water quality information.

[0108] This enables the control device 10 in this embodiment to calculate water quality information on the water to be treated, in the same way as in the case where ultraviolet absorbance is used, for example.

[0109] [Experimental Results in the First Embodiment] Next, a description will be given of the experimental results in the first embodiment. Figures 7 and 8 are diagrams showing the experimental results in the first embodiment.

[0110] First, each graph shown in Fig. 7 will be explained. The graph shown on the left side of Fig. 7 is a graph explaining the remaining rate of the target substance (2-MIB) for each temperature of the water to be treated (the remaining rate of the target substance in the water to be treated after treatment in the water treatment system 100), with the horizontal axis corresponding to the first contact time and the vertical axis corresponding to the remaining rate (measured value) of the target substance. The graph shown on the right side of Fig. 7 is a graph explaining the remaining rate of the target substance for each temperature of the water to be treated, with the horizontal axis corresponding to the first adsorption time and the vertical axis corresponding to the remaining rate (measured value) of the target substance.

[0111] That is, each graph in Fig. 7 shows the adsorption speed (change in residual rate over time) of the target substance under conditions where only the water temperature of the water to be treated is different. Specifically, the graph shown on the left side of Fig. 7 shows the change in residual rate of the target substance versus contact time when the first adsorption efficiency calculated by Equation 2 is not used, and the graph shown on the right side of Fig. 7 shows the change in residual rate of the target substance versus adsorption time when the first adsorption efficiency calculated by Equation 2 is used.

[0112] The graph shown on the right side of Fig. 7 shows a smaller difference in the shape of the graph at the same time due to differences in the temperature of the water to be treated than the graph shown on the left side of Fig. 7. In other words, the adsorption time used in the graph shown on the right side of Fig. 7 shows that, by performing step S1 of Fig. 3 with the first adsorption efficiency, calculation of an injection rate that can stabilize the residual rate of the target substance is realized regardless of differences in the temperature of the water to be treated compared to the case of the contact time used in the graph shown on the left side of Fig. 7.

[0113] Therefore, the example shown in FIG. 7 can be considered to indicate that by calculating the injection rate of powdered activated carbon using the adsorption time calculated by Equation 2, it is possible to calculate an injection rate that can control the residual rate of the target substance with higher accuracy.

[0114] Next, each graph shown in Fig. 8 will be explained. The graph shown on the left side of Fig. 8 is a graph explaining the remaining rate of the target substance (Geosmin) for each treated water differently collected at different locations and times (the remaining rate of the target substance in the treated water after treatment in the water treatment system 100), with the horizontal axis corresponding to the adsorption time of the powdered activated carbon and the vertical axis corresponding to the logarithm of the remaining rate (measured value) of the target substance. The graph shown on the right side of Fig. 8 is a graph explaining the remaining rate of the target substance for each treated water differently collected at different locations and times, with the horizontal axis corresponding to the adsorption time of the powdered activated carbon and the vertical axis corresponding to the value obtained by dividing the logarithm of the remaining rate (measured value) of the target substance by the correction function of fw.

[0115] That is, in each graph shown in Fig. 8, the difference in time change in the residual rate of the target substance for each treated water is smaller in the graph shown on the right side of Fig. 8 than in the graph shown on the left side of Fig. 8. Therefore, each graph shown in Fig. 8 shows that the time change in the logarithm of the residual rate for the target substance, which differs for each treated water, can be expressed by multiplying the time change function by the correction function of fw (in other words, it can be expressed by using the above formula 5).

[0116] Therefore, the example shown in Figure 8 can be interpreted as indicating that by calculating the injection rate of powdered activated carbon using the correction function of fw, it is possible to calculate an injection rate that can control the residual rate of the target substance with higher accuracy. [Explanation of symbols]

[0117] 1: Contact pond 2: Mixing pond 3: Flocculation pond 4: Storage vessel 5: Storage tank 10: Control device 100: Water treatment system 101: CPU 102: Memory 103: Communication device 104: Storage medium 105: Bus 110: Program 130: Information storage area 131: Dynamic viscosity information 132: Operation efficiency information 133: Facility capacity information L1: Line L2: Line L3: Line L4: Line L11: Line L12: Line P1: Pump P2: Pump P3: Pump P11: Pump P12: Pump

Claims

1. An injection rate control device for controlling an injection rate of powdered activated carbon into water to be treated, a time calculation unit that calculates a first adsorption efficiency of odorous substances contained in the water to be treated by the powdered activated carbon based on at least one of the temperature of the water to be treated and an operation performed on the water to be treated, and calculates an adsorption time during which the odorous substances are adsorbed by the powdered activated carbon using the calculated first adsorption efficiency and a contact time between the powdered activated carbon and the odorous substances; and an injection rate calculation unit that calculates an injection rate of the powdered activated carbon by using the calculated adsorption time.

2. The time calculation unit Identifying the kinetic viscosity of the water to be treated corresponding to the water temperature; The injection rate control device according to claim 1 , wherein the first adsorption efficiency is calculated by using the determined kinetic viscosity.

3. The time calculation unit For each of the operations in which the powdered activated carbon and the odorous substance are brought into contact with each other among the plurality of operations on the water to be treated, a first contact time is calculated, which is the contact time during which each operation is performed; calculating a first adsorption time, which is the adsorption time during each operation, from the first contact time corresponding to each operation by using a second adsorption efficiency of the odorous substance by the powdered activated carbon during each operation; The injection rate control device of claim 1 , wherein the adsorption time is calculated by using a total time of the first adsorption times corresponding to each of the one or more operations.

4. An injection rate control device for controlling an injection rate of powdered activated carbon into water to be treated, a water quality calculation unit that classifies soluble organic matter contained in the water to be treated into a plurality of groups and calculates water quality information indicating the water quality of the water to be treated using the concentration of the soluble organic matter for each of the plurality of groups; and an injection rate calculation unit that calculates the injection rate of the powdered activated carbon by using the calculated water quality information.

5. An injection rate control method in which a computer executes a process for controlling an injection rate of powdered activated carbon into water to be treated, comprising: calculating a first adsorption efficiency of odorous substances contained in the water to be treated by the powdered activated carbon based on at least one of the temperature of the water to be treated and an operation performed on the water to be treated, and calculating an adsorption time during which the odorous substances are adsorbed by the powdered activated carbon using the calculated first adsorption efficiency and a contact time between the powdered activated carbon and the odorous substances; The method of claim 1, further comprising: calculating an injection rate of the powdered activated carbon by using the calculated adsorption time.

6. An injection rate control method in which a computer executes a process for controlling an injection rate of powdered activated carbon into water to be treated, comprising: classifying the soluble organic matter in the water to be treated into a plurality of groups, and calculating water quality information indicating the water quality of the water to be treated using the concentration of the soluble organic matter for each of the plurality of groups; The injection rate control method further comprises calculating an injection rate of the powdered activated carbon by using the calculated water quality information.

Images