Water treatment equipment, control device, control method, and program

Abstract

To prevent a decline in the quality of treated water. [Solution] The system comprises a plurality of reaction tanks 400-1, 400-2 into which different waters to be treated containing urea each flow in, a chemical injection unit 200 that injects chemicals into the reaction tanks 400-1, 400-2 via a single chemical injection line, water quality meters 500-1, 500-2 that measure the water quality of the waters to be treated stored in or flowing into each of the reaction tanks 400-1, 400-2, and a control device 100 that calculates the necessary chemical injection conditions for each of the reaction tanks 400-1, 400-2 based on the water quality measured by the water quality meters 500-1, 500-2, and controls the amount of chemical injected by the chemical injection unit 200 so as to satisfy all of the calculated chemical injection conditions.

Description

Technical Field

[0001] The present invention relates to a water treatment facility, a control device, a control method, and a program.

Background Art

[0002] A method is disclosed in which a water-soluble bromide salt and a hypochlorite are added to the water to be treated, the concentration of free residual chlorine in the effluent water in the urea decomposition step of decomposing urea in the water to be treated with the generated hypobromite ions is measured, and the addition amount of the hypochlorite is controlled based on the measured concentration of free residual chlorine (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The method described in Patent Document 1 is a method used for decomposing urea in one reaction tank. When injecting chemicals through a single chemical injection line into a plurality of reaction tanks into which different waters to be treated flow respectively, the injection amount of the chemical controlled based on the water quality in one reaction tank is not necessarily the appropriate injection amount in other reaction tanks. Therefore, when injecting chemicals through a single chemical injection line into a plurality of reaction tanks, if chemicals are injected in an amount calculated based on the water quality in one reaction tank, there is a risk of deteriorating the quality of the treated water.

[0005] An object of the present invention is to provide a water treatment facility, a control device, a control method, and a program capable of preventing a decrease in the quality of treated water.

Means for Solving the Problems

[0006] The water treatment equipment of the present invention is Multiple reaction tanks into which different waters containing urea are to be treated flow, A chemical injection unit that injects chemicals into the plurality of reaction vessels via a single chemical injection line, A water quality meter for measuring the water quality of the water to be treated that is stored in or flows into each of the plurality of reaction tanks, The system includes a control device that calculates the necessary chemical injection conditions for each of the plurality of reaction tanks based on the water quality measured by the water quality meter, and controls the amount of chemical injected by the chemical injection unit so as to satisfy all of the calculated chemical injection conditions.

[0007] Furthermore, the control device of the present invention is A measurement value acquisition unit that acquires water quality values ​​indicating the water quality of each of the waters to be treated that are stored in or flow into multiple reaction tanks into which different waters to be treated containing urea each flow, A chemical injection amount calculation unit calculates the chemical injection conditions required for each of the multiple reaction tanks based on the water quality values ​​acquired by the measurement value acquisition unit, The system includes a chemical injection control unit that controls the amount of chemicals injected into the plurality of reaction vessels via a single chemical injection line so as to satisfy all of the injection conditions for each of the chemicals calculated by the chemical injection amount calculation unit.

[0008] Furthermore, the control method of the present invention is A process for obtaining water quality values ​​representing the water quality of each of the waters to be treated, which are stored in or flow into multiple reaction tanks into which different waters to be treated containing urea each flow, Based on the water quality values ​​obtained, a process is performed to calculate the necessary chemical injection conditions for each of the multiple reaction tanks. The process involves controlling the amount of the chemical injected into the multiple reaction vessels via a single chemical injection line so as to satisfy all of the calculated injection conditions for each of the chemicals.

[0009] Furthermore, the program of the present invention, On the computer, A procedure for obtaining water quality values ​​representing the water quality of each of the waters to be treated, which are stored in or flow into multiple reaction tanks into which different waters to be treated, each containing urea, A procedure for calculating the necessary chemical injection conditions for each of the multiple reaction tanks based on the water quality values ​​obtained, The procedure involves controlling the amount of the chemical injected into the plurality of reaction vessels via a single chemical injection line so as to satisfy all of the injection conditions for each of the chemicals calculated above. [Effects of the Invention]

[0010] In this invention, it is possible to prevent a deterioration in the quality of treated water. [Brief explanation of the drawing]

[0011] [Figure 1] This figure shows an example of a water treatment system to which the water treatment equipment according to the present invention is applied. [Figure 2] This figure shows a first embodiment of a water treatment facility applied to the water treatment system shown in Figure 1. [Figure 3] This figure shows an example of the components of the control device shown in Figure 2. [Figure 4] Figure 2 is a flowchart illustrating an example of how to operate the water treatment facility shown. [Figure 5] This figure shows a second embodiment of a water treatment facility applied to the water treatment system shown in Figure 1. [Figure 6] This figure shows an example of the components of the control device shown in Figure 5. [Figure 7] Figure 5 is a flowchart illustrating an example of how to operate the water treatment facility shown. [Figure 8] This figure shows a third embodiment of a water treatment facility applied to the water treatment system shown in Figure 1. [Figure 9] This figure shows an example of the components of the control device shown in Figure 8. [Figure 10]It is a flowchart for explaining an example of an operation method of the water treatment facility shown in FIG. 8.

Embodiments for Carrying Out the Invention

[0012] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0013] FIG. 1 is a diagram showing an example of a water treatment system to which the water treatment facility according to the present invention is applied. The water treatment system shown in FIG. 1 includes the water treatment facility 10 of the present invention, a primary pure water production system 20, and a subsystem 30. Between the water treatment facility 10 and the primary pure water production system 20, a water treatment device may be provided to remove impurities such as turbidity and TOC (Total Organic Carbon) so that treated water with a suitable water quality for the equipment arranged in the primary pure water production system 20, such as a sand filtration device and an activated carbon filter, is supplied. The primary pure water production system 20 is a water treatment facility that performs a predetermined treatment on the treated water treated by the water treatment facility 10 and supplies the treated water to the subsystem 30. The subsystem 30 may be a secondary pure water production system used in a general water treatment system, and removes trace ions and total organic carbon that could not be completely removed by the primary pure water production system 20. (First Embodiment)

[0014] Figure 2 shows a first embodiment of a water treatment facility applied to the water treatment system shown in Figure 1. In this embodiment, the water treatment facility 10 is installed at the location shown in Figure 1. As shown in Figure 2, the water treatment facility 10 in this embodiment includes a control device 100, a chemical injection unit 200, a chemical injection line 300, branch lines 310-1, 310-2, reaction tanks 400-1, 400-2, water quality meters 500-1, 500-2, thermometers 510-1, 510-2, and flow meters 520-1, 520-2. The control device 100, water quality meters 500-1, 500-2, thermometers 510-1, 510-2, and flow meters 520-1, 520-2 are connected to each other via wired or wireless communication. The number of reaction tanks 400-1, 400-2, branch lines 310-1, 310-2, water quality meters 500-1, 500-2, thermometers 510-1, 510-2, and flow meters 520-1, 520-2 is not limited to 2; it can be 3 or more.

[0015] The chemical injection unit 200 injects chemicals or chemical mixtures (hereinafter referred to as "chemicals") into reaction vessels 400-1 and 400-2 via one chemical injection line 300 and branch lines 310-1 and 310-2. The number (number of types) of chemicals injected by the chemical injection unit 200 is not particularly limited. The amount of chemicals injected by the chemical injection unit 200 via the chemical injection line 300 is controlled by the control device 100. Examples of chemicals injected by the chemical injection unit 200 include sodium bromide (NaBr), sodium hypochlorite (NaClO), pH adjusters, etc.

[0016] The chemical injection line 300 is a route for injecting chemicals injected from the chemical injection section 200 into reaction vessels 400-1 and 400-2. At this time, the chemicals injected from the chemical injection section 200 may be diluted with dilution water in the chemical injection line 300. The chemical injection line 300 branches into branch lines 310-1 and 310-2, which supply chemicals to reaction vessels 400-1 and 400-2, respectively.

[0017] Reaction tanks 400-1 and 400-2 are tanks into which different types of water to be treated, each containing urea, flow. For example, industrial water (tap water) flows into reaction tank 400-1, and recycled wastewater flows into reaction tank 400-2. Alternatively, industrial water (tap water) may flow into reaction tank 400-1, and industrial water (tap water) and recycled wastewater may flow into reaction tank 400-2. Chemicals injected from the chemical injection section 200 are injected into the water to be treated flowing into reaction tanks 400-1 and 400-2 via the chemical injection line 300 and branch lines 310-1 and 310-2, decomposing and removing the urea contained in the water to be treated. The treated water from which urea has been decomposed and removed in each of reaction tanks 400-1 and 400-2 is supplied from reaction tanks 400-1 and 400-2 to the respective devices and systems that utilize (process) the treated water.

[0018] Water quality meters 500-1 and 500-2 measure the water quality of the water to be treated stored in reaction tanks 400-1 and 400-2, respectively. For example, water quality meters 500-1 and 500-2 measure the pH value of the water to be treated stored in reaction tanks 400-1 and 400-2, respectively. Water quality meters 500-1 and 500-2 may also measure values ​​directly or indirectly related to the urea decomposition reaction, such as ammonia concentration, urea concentration, TOC concentration, residual chlorine concentration, residual bromine concentration, turbidity, color, metal concentrations such as iron and manganese, and hardness component concentrations such as calcium, magnesium, and vanadium, in the water to be treated stored in reaction tanks 400-1 and 400-2, respectively. Note that the water quality meters 500-1 and 500-2 may be installed not in the reaction tanks 400-1 and 400-2 respectively, but in the piping that supplies the treated water to each of the reaction tanks 400-1 and 400-2, or in the water treatment plant, recycled water plant, etc. Each of the water quality meters 500-1 and 500-2 notifies the control device 100 of the measured water quality values.

[0019] Thermometers 510-1 and 510-2 measure the water temperature of the water to be treated stored in reaction tanks 400-1 and 400-2, respectively. Thermometers 510-1 and 510-2 each notify the control device 100 of the measured water temperature.

[0020] Each of the flow meters 520-1 and 520-2 measures the flow rate of the water to be treated flowing into each of the reaction tanks 400-1 and 400-2, or the flow rate of the water to be treated flowing out of each of the reaction tanks 400-1 and 400-2. Each of the flow meters 520-1 and 520-2 notifies the control device 100 of the measured flow rate.

[0021] The control device 100 controls the injection amount, which is the injection condition for the chemicals injected by the chemical injection unit 200 into the chemical injection line 300, based on the water quality values ​​notified by the water quality meters 500-1 and 500-2, respectively. The control device 100 may also control the injection amount, which is the injection condition for the chemicals injected by the chemical injection unit 200 into the chemical injection line 300, based on the water quality values ​​notified by the water quality meters 500-1 and 500-2, respectively, and the water temperature values ​​notified by the thermometers 510-1 and 510-2, respectively. The control device 100 may also control the injection amount, which is the injection condition for the chemicals injected by the chemical injection unit 200 into the chemical injection line 300, based on the water quality values ​​notified by the water quality meters 500-1 and 500-2, respectively, the water temperature values ​​notified by the thermometers 510-1 and 510-2, respectively, and the flow rate values ​​notified by the flow meters 520-1 and 520-2, respectively.

[0022] Figure 3 shows an example of the components of the control device 100 shown in Figure 2. As shown in Figure 3, the control device 100 shown in Figure 2 includes a measurement value acquisition unit 110, a chemical injection amount calculation unit 120, and a chemical injection control unit 130. Note that Figure 3 shows only the main components of the control device 100 shown in Figure 2 that are relevant to this embodiment.

[0023] The measurement value acquisition unit 110 acquires water quality values ​​as measured values ​​from water quality meters 500-1 and 500-2, respectively. The measurement value acquisition unit 110 also acquires water temperature values ​​as measured values ​​from thermometers 510-1 and 510-2, respectively. The measurement value acquisition unit 110 also acquires flow rate values ​​as measured values ​​from flowmeters 520-1 and 520-2, respectively. The measurement value acquisition unit 110 notifies the chemical injection amount calculation unit 120 of the acquired measurement values.

[0024] The chemical injection amount calculation unit 120 calculates the injection amount, which is the injection condition for the chemicals required for each of the reaction tanks 400-1 and 400-2, based on the measured values ​​notified by the measured value acquisition unit 110. The chemical injection amount calculation unit 120 calculates the injection amount, which is the injection condition for the chemicals required for each of the reaction tanks 400-1 and 400-2, based on the water quality values ​​(e.g., pH value) notified by the measured value acquisition unit 110. For example, the chemical injection amount calculation unit 120 calculates the injection amount, which is the injection condition for the chemicals required for each of the reaction tanks 400-1 and 400-2, in order to remove urea from the water to be treated in the reaction tanks 400-1 and 400-2 and bring the water quality notified by the measured value acquisition unit 110 to a predetermined water quality. Furthermore, if a mechanism (e.g., a heat exchanger) is provided to control the water temperature of the water to be treated stored in the reaction tanks 400-1 and 400-2, the chemical injection amount calculation unit 120 calculates the injection amount, which is the injection condition for the chemicals required for each of the reaction tanks 400-1 and 400-2, including the control of the water temperature of the water to be treated based on the measured value (water temperature value) notified by the measured value acquisition unit 110. Since controlling the water temperature to a higher level improves the urea removal treatment performance, the chemical injection amount calculation unit 120 can calculate the required amount of chemicals for each of the reaction tanks 400-1 and 400-2 to be less than in the case where water temperature control is not performed. For example, the water temperature value and the range of increase or decrease in the injection amount may be set in advance in correspondence, and the chemical injection amount calculation unit 120 may calculate the amount of chemicals required for reaction tanks 400-1 and 400-2 based on the water quality value notified by the measurement value acquisition unit 110, and then increase or decrease the calculated injection amount using the range of increase or decrease corresponding to the water temperature value notified by the measurement value acquisition unit 110. Alternatively, the chemical injection amount calculation unit 120 may calculate the injection amount, which is the injection condition for the chemicals required for reaction tanks 400-1 and 400-2, based on the water quality value and flow rate value notified by the measurement value acquisition unit 110. In this case, the higher the flow rate value, the more chemicals the chemical injection amount calculation unit 120 will calculate to be required for reaction tanks 400-1 and 400-2.For example, the flow rate value and the range of increase or decrease in the injection amount may be set in advance in correspondence, and the chemical injection amount calculation unit 120 may calculate the amount of chemicals to be injected into each of the reaction tanks 400-1 and 400-2 based on the water quality value notified by the measurement value acquisition unit 110, and then increase or decrease the calculated injection amount using the range of increase or decrease that is associated with the flow rate value notified by the measurement value acquisition unit 110. The chemical injection amount calculation unit 120 then notifies the chemical injection control unit 130 of the calculated amount of chemicals to be injected into each of the reaction tanks 400-1 and 400-2.

[0025] The chemical injection control unit 130 controls the amount of chemical injected by the chemical injection unit 200 via the chemical injection line 300 into reaction vessels 400-1 and 400-2 so as to satisfy the required amount of chemicals for each of the reaction vessels 400-1 and 400-2 calculated by the chemical injection amount calculation unit 120. For example, the chemical injection control unit 130 controls the chemical injection unit 200 to inject the largest amount of chemical among the required amounts of chemicals for each of the reaction vessels 400-1 and 400-2 calculated by the chemical injection amount calculation unit 120. To explain with a more specific numerical example, if the required amount of chemicals for reaction vessel 400-1 calculated by the chemical injection amount calculation unit 120 is 5 ppm and the required amount of chemicals for reaction vessel 400-2 is 3 ppm, the chemical injection control unit 130 controls the chemical injection unit 200 to inject the largest amount, which is 5 ppm of the chemical.

[0026] The following describes the operation method of the water treatment facility 10 shown in Figure 2. Figure 4 is a flowchart illustrating an example of the operation method of the water treatment facility 10 shown in Figure 2.

[0027] First, water quality meters 500-1 and 500-2 each measure the water quality of the water to be treated stored in reaction tanks 400-1 and 400-2, respectively. The measurement value acquisition unit 110 acquires the water quality values ​​measured by water quality meters 500-1 and 500-2 (step S1). Next, the chemical injection amount calculation unit 120 calculates the injection amount, which is the injection condition for the chemicals required for reaction tanks 400-1 and 400-2, based on the water quality values ​​acquired by the measurement value acquisition unit 110 (step S2). The specific calculation method is as described above. The chemical injection control unit 130 controls the amount of chemicals injected by the chemical injection unit 200 so as to satisfy the amount of chemicals required for reaction tanks 400-1 and 400-2 calculated by the chemical injection amount calculation unit 120 (step S3). The chemical injection unit 200 then injects the amount of chemical controlled by the chemical injection control unit 130 into the reaction vessels 400-1 and 400-2 via the chemical injection line 300 and branch lines 310-1 and 310-2.

[0028] In this configuration, a system in which chemicals are injected via a single chemical injection line 300 into multiple reaction tanks 400-1 and 400-2, each receiving different treated water containing urea, calculates the injection amount, which is the chemical injection condition based on the water quality, for each reaction tank 400-1 and 400-2. The injection amount of chemicals injected into each reaction tank 400-1 and 400-2 via the chemical injection line 300 and branch lines 310-1 and 310-2 is then controlled to meet the calculated chemical injection amount for each reaction tank 400-1 and 400-2. Therefore, even if there is variation in the chemical injection amount calculated based on the water quality for each reaction tank 400-1 and 400-2, at least an appropriate amount of chemicals is injected into each reaction tank 400-1 and 400-2, thereby preventing a deterioration in the quality of the treated water from which urea has been removed. (Second Embodiment)

[0029] Figure 5 shows a second embodiment of the water treatment equipment applied to the water treatment system shown in Figure 1. In this embodiment, the water treatment equipment 11 is installed in the same location as the water treatment equipment 10 shown in Figure 1. As shown in Figure 5, the water treatment equipment 11 in this embodiment includes a control device 101, a chemical injection unit 200, a chemical injection line 300, branch lines 310-1, 310-2, reaction tanks 400-1, 400-2, water quality meters 500-1, 500-2, thermometers 510-1, 510-2, and flow meters 520-1, 520-2. The control device 101, water quality meters 500-1, 500-2, thermometers 510-1, 510-2, and flow meters 520-1, 520-2 are connected to each other via wired or wireless communication. The chemical injection section 200, chemical injection line 300, branch lines 310-1, 310-2, reaction vessels 400-1, 400-2, water quality meters 500-1, 500-2, thermometers 510-1, 510-2, and flow meters 520-1, 520-2 are the same as those in the first embodiment.

[0030] The control device 101 controls the injection amount, which is the injection condition for the chemicals injected by the chemical injection unit 200 into the chemical injection line 300, based on the water quality values ​​notified by the water quality meters 500-1 and 500-2, respectively. The control device 101 may also control the injection amount, which is the injection condition for the chemicals injected by the chemical injection unit 200 into the chemical injection line 300, based on the water quality values ​​notified by the water quality meters 500-1 and 500-2, respectively, and the water temperature values ​​notified by the thermometers 510-1 and 510-2, respectively. The control device 101 may also control the injection amount, which is the injection condition for the chemicals injected by the chemical injection unit 200 into the chemical injection line 300, based on the water quality values ​​notified by the water quality meters 500-1 and 500-2, respectively, the water temperature values ​​notified by the thermometers 510-1 and 510-2, respectively, and the flow rate values ​​notified by the flow meters 520-1 and 520-2, respectively.

[0031] Figure 6 shows an example of the components of the control device 101 shown in Figure 5. As shown in Figure 6, the control device 101 shown in Figure 5 includes a measurement value acquisition unit 110, a drug injection amount calculation unit 120, a drug injection control unit 131, and a storage unit 141. The measurement value acquisition unit 110 and the drug injection amount calculation unit 120 may be the same as those in the first embodiment. Note that Figure 6 shows only the main components of the control device 101 shown in Figure 5 that are relevant to this embodiment.

[0032] The memory unit 141 stores the cost of injection, including the unit price of the chemicals and the amount of chemicals injected; the power consumption consumed for equipment operation, including the power consumption to raise the water temperature of the treated water; and the CO2 equivalent value calculated based on the equipment operation. The power consumption and CO2 equivalent value may also be measured and calculated as needed and stored in the memory unit 141.

[0033] In addition to the functions of the chemical injection control unit 130 in the first embodiment, the chemical injection control unit 131 also selects the amount of chemical to be injected into the reaction vessel 400-1 based on the operating conditions corresponding to each injection amount, which are stored in the storage unit 141, if there are multiple amounts of chemical to be injected into the reaction vessel 400-1 calculated by the chemical injection amount calculation unit 120. As operating conditions, at least one of cost, power consumption, and CO2 equivalent value is used. The operating conditions used may be set (input) from outside the control device 101. If there are also multiple amounts of chemical to be injected into the reaction vessel 400-2 calculated by the chemical injection amount calculation unit 120, the chemical injection control unit 131 makes a similar selection. This selection is made based on conditions suitable for operation, such as whether to improve urea removal performance by increasing the water temperature of the water to be treated (increasing power consumption) or to improve urea removal performance by increasing the amount of chemical injected into the water to be treated. In other words, the selection is made based on conditions suitable for operation, such as prioritizing cost, prioritizing power consumption, or prioritizing CO2 equivalent value. For example, if the chemical injection amount calculation unit 120 calculates the amount of chemicals to be injected so that the water quality value of the treated water from which urea has been removed reaches a desired value, and as a result the chemical injection unit 200 obtains two patterns: one in which an acid is added to raise the pH value to 6, and 2 ppm of sodium bromide and 2 ppm of sodium hypochlorite are injected; and another in which no acid is added, the pH value is raised to 7, and 3 ppm of sodium bromide and 3 ppm of sodium hypochlorite are injected, then if cost is the priority, the chemical injection control unit 131 should calculate the cost of injecting the chemicals based on the unit price and injection amount of the chemicals, using the information stored in the storage unit 141, and select the pattern that results in lower costs.

[0034] The drug injection control unit 131 controls the amount of drug injected by the drug injection unit 200 so as to satisfy the injection amount of each selected drug. This control may be the same as the control performed by the drug injection control unit 130 in the first embodiment.

[0035] The operation method of the water treatment facility 11 shown in Figure 5 will be described below. Figure 7 is a flowchart illustrating an example of the operation method of the water treatment facility 11 shown in Figure 5.

[0036] First, water quality meters 500-1 and 500-2 measure the water quality of the water to be treated stored in reaction tanks 400-1 and 400-2, respectively. The measurement value acquisition unit 110 acquires the water quality values ​​measured by water quality meters 500-1 and 500-2, respectively (step S11). Next, the chemical injection amount calculation unit 120 calculates the injection amount, which is the injection condition for the chemicals required for reaction tanks 400-1 and 400-2, based on the water quality values ​​acquired by the measurement value acquisition unit 110 (step S12). The specific calculation method is the same as the calculation method in the first embodiment.

[0037] Step S12 determines whether there are multiple calculated results for the amount of chemicals to be injected by the chemical injection amount calculation unit 120 (Step S13). If there are multiple calculated results for the amount of chemicals to be injected by the chemical injection amount calculation unit 120, the chemical injection control unit 131 selects the required amount of chemicals to be injected into each of the reaction vessels 400-1 and 400-2 based on at least one of the cost, power consumption, and CO2 equivalent value corresponding to each injection amount, which are stored in the memory unit 141 (Step S14). The specific selection method is as described above. The chemical injection control unit 131 controls the amount of chemicals injected by the chemical injection unit 200 to satisfy the selected amount of chemicals to be injected (Step S15). Then, the chemical injection unit 200 injects the amount of chemicals controlled by the chemical injection control unit 130 into the reaction vessels 400-1 and 400-2 via the chemical injection line 300 and branch lines 310-1 and 310-2.

[0038] Thus, in this embodiment, in addition to the functions of the first embodiment, if there are multiple patterns of calculated injection amounts, the injection amount pattern to be adopted is selected based on other operating conditions. This makes it possible to inject an amount of chemical suitable for the operating method of each piece of equipment. (Third embodiment)

[0039] Figure 8 shows a third embodiment of the water treatment equipment applied to the water treatment system shown in Figure 1. In this embodiment, the water treatment equipment 12 is installed in the same location as the water treatment equipment 10 shown in Figure 1. As shown in Figure 8, the water treatment equipment 12 in this embodiment includes a control device 102, a chemical injection unit 200, a chemical injection line 300, branch lines 310-1, 310-2, reaction tanks 400-1, 400-2, water quality meters 500-1, 500-2, thermometers 510-1, 510-2, and flow meters 520-1, 520-2. The control device 102, water quality meters 500-1, 500-2, thermometers 510-1, 510-2, and flow meters 520-1, 520-2 are connected to each other via wired or wireless communication. The chemical injection section 200, chemical injection line 300, branch lines 310-1, 310-2, reaction tanks 400-1, 400-2, water quality meters 500-1, 500-2, thermometers 510-1, 510-2, and flow meters 520-1, 520-2 are the same as those in the first embodiment. In this embodiment, the treated water from which urea has been decomposed and removed in reaction tanks 400-1 and 400-2 merges with each other and is supplied to devices or systems that utilize (process) the merged treated water.

[0040] The control device 102 controls the injection amount of chemicals injected by the chemical injection unit 200 into the chemical injection line 300, based on the water quality values ​​reported from the water quality meters 500-1 and 500-2, respectively, and the confluence ratio of treated water from the reaction tanks 400-1 and 400-2, respectively. The control device 102 may also control the injection amount of chemicals injected by the chemical injection unit 200 into the chemical injection line 300, based on the water quality values ​​reported from the water quality meters 500-1 and 500-2, respectively, the water temperature values ​​reported from the thermometers 510-1 and 510-2, respectively, and the confluence ratio of treated water from the reaction tanks 400-1 and 400-2, respectively. Furthermore, the control device 102 may control the injection amount, which is the injection condition for the chemicals injected by the chemical injection unit 200 into the chemical injection line 300, based on the water quality values ​​reported from the water quality meters 500-1 and 500-2 respectively, the water temperature values ​​reported from the thermometers 510-1 and 510-2 respectively, the flow rate values ​​reported from the flowmeters 520-1 and 520-2 respectively, and the confluence ratio of the treated water from the reaction tanks 400-1 and 400-2 respectively.

[0041] Figure 9 shows an example of the components of the control device 102 shown in Figure 8. As shown in Figure 9, the control device 102 shown in Figure 8 includes a measurement value acquisition unit 110, a drug injection amount calculation unit 120, a drug injection control unit 132, and a storage unit 142. The measurement value acquisition unit 110 and the drug injection amount calculation unit 120 may be the same as those in the first embodiment. Note that Figure 9 shows only the main components of the control device 102 shown in Figure 8 that are relevant to this embodiment.

[0042] The memory unit 142 has pre-stored the combined ratio of treated water from reaction tanks 400-1 and 400-2, respectively. The combined ratio stored in the memory unit 142 may be a value predetermined when the system was constructed, a value calculated based on the required quality from the treated water supplier, or a value calculated based on the processing capacity and actual processing conditions (water quality values, etc.) of reaction tanks 400-1 and 400-2, respectively.

[0043] The chemical injection control unit 132 reads the confluence ratio of treated water from reaction tanks 400-1 and 400-2, respectively, stored in the memory unit 142. Based on the amount of chemicals injected by the chemical injection amount calculation unit 120 and the confluence ratio of treated water from reaction tanks 400-1 and 400-2 read from the memory unit 142, the chemical injection control unit 132 controls the amount of chemicals injected by the chemical injection unit 200. For example, the chemical injection control unit 132 controls the chemical injection unit 200 to inject a chemical amount that is closer to the amount of chemicals injected by the chemical injection amount calculation unit 120 for a reaction tank with a high confluence ratio, multiplied by a high weighting coefficient, than the amount of chemicals injected by the chemical injection amount calculation unit 120 for a reaction tank with a low confluence ratio. To illustrate with a specific example using numerical values, for instance, if the chemical injection amount calculation unit 120 calculates that the amount of chemical to be injected into reaction tank 400-1 is 3 ppm, and the chemical injection amount calculation unit 120 calculates that the amount of chemical to be injected into reaction tank 400-2 is 5 ppm, and the confluence ratio of the treated water from reaction tank 400-1 and the treated water from reaction tank 400-2 is 4:1, then the chemical injection control unit 132 can control the chemical injection unit 200 to inject an amount of chemical of (3 ppm × 0.8) + (5 ppm × 0.2) = 3.4 ppm. In this way, even if 5 ppm of chemical is required for reaction tank 400-2, which has lower processing performance, if the confluence ratio of reaction tank 400-2 is low, the amount of chemical injected by the chemical injection unit 200 can be less than the amount calculated by the chemical injection amount calculation unit 120 for reaction tank 400-2, while still ensuring the required quality of the combined treated water. As a result, the amount of chemical injected by the chemical injection unit 200 can be reduced.

[0044] The following describes the operation method of the water treatment facility 12 shown in Figure 8. Figure 10 is a flowchart illustrating an example of the operation method of the water treatment facility 12 shown in Figure 8.

[0045] First, water quality meters 500-1 and 500-2 measure the water quality of the water to be treated stored in reaction tanks 400-1 and 400-2, respectively. The measurement value acquisition unit 110 acquires the water quality values ​​measured by water quality meters 500-1 and 500-2, respectively (step S21). Next, the chemical injection amount calculation unit 120 calculates the injection amount, which is the injection condition for the chemicals required for reaction tanks 400-1 and 400-2, based on the water quality values ​​acquired by the measurement value acquisition unit 110 (step S22). The specific calculation method is the same as the calculation method in the first embodiment.

[0046] The chemical injection control unit 132 reads the confluence ratio of treated water from reaction tanks 400-1 and 400-2 stored in the memory unit 142 (step S23). Based on the amount of chemical to be injected by the chemical injection unit 120 calculated by the chemical injection amount calculation unit 120 and the confluence ratio of treated water from reaction tanks 400-1 and 400-2 read from the memory unit 142, the chemical injection control unit 132 controls the amount of chemical to be injected by the chemical injection unit 200 (step S24). The specific control method is as described above. Then, the chemical injection unit 200 injects the amount of chemical controlled by the chemical injection control unit 132 into reaction tanks 400-1 and 400-2 via the chemical injection line 300 and branch lines 310-1 and 310-2.

[0047] In this configuration, when treated water from at least two of the multiple reaction tanks is combined and supplied, the chemical injection control unit 132 controls the amount of chemical injected by the chemical injection unit 200 based on the amount of chemical to be injected into each reaction tank and the confluence ratio. As a result, if the confluence ratio of treated water from the reaction tank with high treatment performance is high, the amount of chemical injected into the reaction tank with low treatment performance can be reduced.

[0048] The above explanation describes how each component is assigned a specific function (process), but this assignment is not limited to those described above. Furthermore, the configuration of the components described above is merely an example and is not limited to it.

[0049] The processing performed by each of the control devices 100 to 102 described above may be carried out by logic circuits created according to their respective purposes. Alternatively, a computer program (hereinafter referred to as "program") describing the processing content as a procedure may be recorded on a recording medium readable by each of the control devices 100 to 102, and the program recorded on this recording medium may be read and executed by each of the control devices 100 to 102. The recording medium readable by each of the control devices 100 to 102 refers to portable recording media such as floppy disks, magneto-optical disks, DVDs (Digital Versatile Discs), CDs (Compact Discs), Blu-ray Discs, USB (Universal Serial Bus) memory, and SD cards, as well as memory such as ROM (Read Only Memory), RAM (Random Access Memory), and HDDs (Hard Disc Drives) built into each of the control devices 100 to 102. The program recorded on this recording medium is read by a CPU (not shown) provided in each of the control devices 100 to 102, and the same processing as described above is performed under the control of the CPU. Here, the CPU operates as a computer that executes the program read from the recording medium on which the program is recorded. [Explanation of symbols]

[0050] 10-12 Water Treatment Facilities 20 Primary pure water production system 30 subsystems 100~102 Control device 110 Measurement value acquisition unit 120 Drug injection volume calculation unit 130-132 Drug injection control unit 141,142 Storage section 200 Chemical injection section 300 drug injection lines 310-1, 310-2 Branch Line 400-1, 400-2 reaction vessels 500-1,500-2 Water quality meter 510-1, 510-2 Thermometers 520-1, 520-2 Flow Meters

Claims

1. Multiple reaction tanks into which different waters containing urea are to be treated each, A chemical injection unit that injects chemicals into the plurality of reaction vessels via a single chemical injection line, A water quality meter for measuring the water quality of the water to be treated that is stored in or flows into each of the plurality of reaction tanks, A water treatment facility comprising: a control device that calculates the required chemical injection conditions for each of the plurality of reaction tanks based on the water quality measured by the water quality meter, and controls the amount of chemical injected by the chemical injection unit so as to satisfy all of the calculated chemical injection conditions.

2. In the water treatment equipment described in claim 1, The control device is a water treatment facility that controls the chemical injection unit to inject the amount of chemical indicated by the injection condition that results in the largest amount of chemical injection among the calculated chemical injection conditions into each of the plurality of reaction tanks.

3. In the water treatment facility according to claim 1 or claim 2, Each of the plurality of reaction tanks has a thermometer for measuring the temperature of the water to be treated stored in it. The control device is a water treatment system that calculates the injection conditions for the chemicals required for each of the plurality of reaction tanks based on the water quality measured by the water quality meter and the temperature measured by the thermometer.

4. In the water treatment facility according to claim 1 or claim 2, The system includes a flow meter for measuring the amount of water to be treated flowing into each of the plurality of reaction tanks or the amount of water to be treated flowing out from each of the plurality of reaction tanks. The control device is a water treatment system that calculates the injection conditions for the chemicals required for each of the plurality of reaction tanks based on the water quality measured by the water quality meter and the inflow or outflow rate measured by the flow meter.

5. In the water treatment facility according to claim 1 or claim 2, When there are multiple injection conditions for the chemicals required for each of the calculated multiple reaction vessels, the control device calculates the cost, power consumption, and CO2 levels according to each injection condition. 2 A water treatment facility that selects the necessary chemical injection conditions for each of the plurality of reaction vessels based on at least one of the conversion values, and controls the amount of chemical injected by the chemical injection unit to satisfy the selected chemical injection conditions.

6. In the water treatment equipment described in claim 1, The control device is a water treatment system that controls the amount of chemical injected by the chemical injection unit based on the confluence ratio of treated water from at least two of the plurality of reaction tanks when treated water from the two reaction tanks are combined.

7. A measurement value acquisition unit that acquires water quality values ​​indicating the water quality of each of the waters to be treated that are stored in or flow into multiple reaction tanks into which different waters to be treated containing urea each flow, A chemical injection amount calculation unit calculates the chemical injection conditions required for each of the multiple reaction tanks based on the water quality values ​​acquired by the measurement value acquisition unit, A control device comprising: a chemical injection control unit that controls the amount of chemicals injected into the plurality of reaction vessels via a single chemical injection line so as to satisfy all of the injection conditions for each of the chemicals calculated by the chemical injection amount calculation unit.

8. A process for obtaining water quality values ​​representing the water quality of each of the waters to be treated, which are stored in or flow into multiple reaction tanks into which different waters to be treated containing urea each flow, Based on the water quality values ​​obtained, a process is performed to calculate the necessary chemical injection conditions for each of the multiple reaction tanks. A control method that performs a process to control the amount of chemicals injected into the plurality of reaction vessels via a single chemical injection line so as to satisfy all of the injection conditions for each of the chemicals calculated above.

9. On the computer, A procedure for obtaining water quality values ​​representing the water quality of each of the waters to be treated, which are stored in or flow into multiple reaction tanks into which different waters to be treated, each containing urea, A procedure for calculating the necessary chemical injection conditions for each of the multiple reaction tanks based on the water quality values ​​obtained, A program for executing a procedure to control the amount of chemicals injected into the plurality of reaction vessels via a single chemical injection line so as to satisfy all of the injection conditions for each of the chemicals calculated above.

Images