JP2023174395A - Water treatment system and method of operating water treatment system - Google Patents

Abstract

To provide a water treatment system that accurately calculates an appropriate injection rate of powdered activated carbon for removing musty-smelling substances from raw water and uses an appropriate amount of powdered activated carbon.SOLUTION: A water treatment system includes a water treatment facility 10 and a control unit 20 for controlling the water treatment facility. The water treatment system also includes an odor sensor 1 that measures odors caused by odorous substance contained in raw water, a water quality sensor 3 that measures water quality data of raw water, an event data input unit 5 that inputs various data related to events that affect the mold odor, and an external data input unit 4 for the input of external data including weather-related data affecting the mold odor. The control unit 20 calculates the activated carbon injection rate necessary to reduce the mold odor substance to a predetermined reference value or less based on the odor, the water quality data, the external data, and the event data.SELECTED DRAWING: Figure 1

Description

The present invention relates to a water treatment system and a method of operating a water treatment system.

In general, a water treatment system (water purification plant) includes water treatment equipment that converts raw water to a desired quality, and a control unit that controls the water treatment equipment based on measurement data such as the quality of the raw water. Water treatment equipment is equipment that performs water purification treatment on raw water obtained from dams, rivers, etc. Water treatment equipment includes, for example, a landing well that stabilizes the water level of raw water and adjusts the amount of water, a mixing pond that stirs and evenly disperses the injected flocculant and other chemicals, and a water treatment pond that removes turbidity from the raw water that has been injected with the flocculant. A flocculation pond that flocculates into minute flocs, a sedimentation basin that sinks and removes the flocs that have grown through flocculation treatment, a filtration basin that removes turbidity that cannot be removed by the sedimentation basin, and a storage basin for filtered water. It consists of a water purification pond, etc. The control unit has the function of controlling the water treatment equipment, including controlling the water volume adjustment unit for raw water in the receiving well, controlling each chemical injection mechanism for injecting chemicals into the mixing basin, stirring control of the coagulation basin, and controlling the settling basin. , adjust the water level of the filtration pond, etc.

By the way, water treatment equipment is basically based on coagulation sedimentation treatment and filtration treatment mainly for the purpose of removing suspended matter, and powder activated carbon treatment, ozone treatment, etc. are combined depending on the properties of the raw water quality. Powdered activated carbon is injected as an emergency measure to remove odor substances such as mold odor or trihalomethane precursors when the concentration of odor substances such as mold odor or trihalomethane precursors contained in raw water becomes high. Powdered activated carbon injected into raw water is usually disposed of as part of the purified water sludge. Although this powdered activated carbon has a great effect on removing odor substances, it is expensive, and as the amount of injection and the number of days of injection increase, the operating cost increases.

Cases of mold-smelling substances occurring in the raw water of water treatment plants due to the proliferation of algae in upstream dam reservoirs have been reported in various places. It has been reported that the majority of complaints from users (residents, etc.) regarding tap water's strange odor and taste are due to this mold odor. Humans can detect moldy odor substances (2-MIB/dimethylisoborneol, geosmin, etc.) even at concentrations as low as ppt, but in order to accurately measure these substances quantitatively, a gas chromatograph/mass spectrometer (GC/MS) is required. ), which requires expensive analytical equipment such as Various odor sensors (odor detection devices) that measure odor are available as a method for detecting moldy odor substances at a lower cost. Odor sensors using semiconductor elements are capable of detecting moldy odor substances in the air at a predetermined concentration or higher, but it is measured as the overall odor intensity including other odor components other than moldy odor components. cannot be measured quantitatively. In other words, there is a problem in that an inexpensive semiconductor-type odor sensor cannot directly measure the concentration of a musty-smelling substance.

In order to estimate the concentration of musty odor substances, there is a method of calculating the odor concentration by diluting raw water until humans can no longer detect the musty odor through a sensory test. However, this method still has problems in that it depends on the sensitivity and physical condition of the individual who conducts the test, and that it requires time and effort. If a musty odor is detected in raw water, it is necessary to promptly determine the injection rate of powdered activated carbon to remove the musty odor. Therefore, methods have been developed to automatically calculate the activated carbon injection rate based on raw water quality data.

A method of automatically calculating the activated carbon injection rate based on water quality data of raw water is disclosed in, for example, Patent Document 1 (Japanese Patent Laid-Open No. 2015-157239). In the technology of Patent Document 1, the quality of treated water is predicted from water quality data including the turbidity of raw water and the concentration of musty-smelling substances, and the flocculant injection rate and activated carbon injection rate are determined by taking into account the costs of the flocculant and activated carbon. The method is described. In the case of this Patent Document 1, it is necessary to quantitatively obtain the turbidity of raw water and the concentration of a musty odor substance, and it is described that a gas chromatograph mass spectrometer is used to quantitatively measure the musty odor. On the other hand, Patent Document 2 (Japanese Unexamined Patent Publication No. 2020-34436) discloses an odor detection device (odor sensor) that detects a musty odor substance using a semiconductor element.

Japanese Patent Application Publication No. 2015-157239 JP2020-34436A

At many water treatment plants, operators regularly check the odor of raw water through a sensory test using their sense of smell, and if they determine that a musty odor has occurred, they calculate the injection rate of powdered activated carbon according to the odor concentration, and the activated carbon Powdered activated carbon corresponding to the injection rate is injected into the raw water. At this time, since the raw water contains substances that adsorb to activated carbon, such as chromaticity components, in addition to moldy odor substances, the injection rate of powdered activated carbon should be set in consideration of the consumption of powdered activated carbon by these substances. There is a need. In this case, there is a tendency to inject powdered activated carbon with sufficient likelihood to reliably remove moldy substances. Injecting excessive powdered activated carbon is effective in obtaining good water quality with reliably reduced mold odor, but it increases the consumption of expensive powdered activated carbon and increases operating costs. Therefore, it is necessary to optimize the injection rate of powdered activated carbon to avoid excessive injection and reduce operating costs while maintaining sufficient removal performance so that the treated water meets water quality standards.

The problem to be solved by the present invention is to calculate an appropriate injection rate of powdered activated carbon for removing musty-smelling substances in raw water, and to enable the powdered activated carbon to be appropriately injected. The method described in Patent Document 1 requires an odor sensor such as a gas chromatograph mass spectrometer that measures mold odor with high precision, and there is a problem that the installation cost is high.

In addition, the method described in Patent Document 2 reliably extracts the odor components in the raw water into the gas phase by stirring the raw water with air, etc., and then arranges the odor components in the raw water so as to be in contact with the semiconductor elements. It is also possible to measure odor components. Therefore, it is expected that changes in odor components in raw water can be automatically and continuously measured. However, in the odor measurement using the semiconductor element disclosed in Document 2, the overall odor intensity of the odor contained in raw water is detected. Therefore, when calculating the activated carbon injection rate based on the measured value of an odor sensor using a semiconductor element, it is necessary to estimate the portion of the intensity of the detected odor that is derived from the musty odor substance. For this reason, when an odor sensor detects an increase in odor, it is necessary to estimate the concentration of musty-smelling substances through a sensory test and to consider the activated carbon injection rate using a jar test.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a water treatment system and a method of operating the water treatment system that can accurately determine the activated carbon injection rate necessary to remove moldy odor substances. purpose.

In order to solve the above problems, the present invention provides, for example, a water treatment system including water treatment equipment and a control unit for controlling the water treatment equipment, an odor sensor that measures odor due to odorous substances contained in raw water; a water quality sensor that measures water quality data of the raw water; an event data input unit that inputs various data related to events that affect mold odor; an external data input unit including weather-related data that affects odor; This is a water treatment system that calculates the activated carbon injection rate necessary to reduce the amount of activated carbon.

In order to solve the above problems, another example of the present invention is a method of operating a water treatment system in which powdered activated carbon is extracted into raw water in order to reduce mold odor in water treatment equipment, comprising: It includes an odor sensor that measures odor due to odorous substances contained in the raw water of the water treatment facility, and a water quality sensor that measures water quality data of the raw water, and the odor measured by the odor sensor and the water quality data. Based on event data related to events that affect mold odor, and external data related to weather that affects mold odor, the activated carbon injection rate necessary to reduce mold odor to below a predetermined standard value is determined. This is a method of operating a water treatment system that uses calculations.

The present invention provides a water treatment system and a water treatment system that can accurately determine the injection rate of powdered activated carbon to remove musty-smelling substances, ensure good water quality of treated water, and suppress excessive use of activated carbon. Driving method can be provided.

FIG. 1 is a configuration diagram of a water treatment system in Example 1 of the present invention. FIG. 2 is a flowchart of the activated carbon injection rate calculation procedure in Example 1. FIG. 3 is a diagram for explaining the effects of the first embodiment. FIG. 4 is a flowchart of the activated carbon injection rate calculation procedure in Example 2.

Hereinafter, embodiments (examples) will be described in detail using the drawings. Note that the present invention is not to be interpreted as being limited to the contents of the embodiments described below. Those skilled in the art will easily understand that the configuration can be modified without departing from the technical idea or gist of the present invention. Furthermore, in the configuration of the embodiment described below, the same equipment and parts having similar operations and functions may be denoted by the same reference numerals, and redundant explanations may be omitted. Additionally, the positions, sizes, shapes, ranges, etc. of each component shown in the drawings are simplified to facilitate understanding of the present invention, and the actual positions, sizes, shapes, ranges, etc. of each component are shown in a simplified manner. It doesn't represent it.

≪Example 1≫
Example 1 of the present invention will be described below with reference to FIGS. 1, 2, and 3. FIG. 1 is a configuration diagram of a water treatment system in Example 1 of the present invention. FIG. 2 is a diagram showing a flow of activated carbon injection rate calculation procedure in Example 1. FIG. 3 is a diagram for explaining the effects of the first embodiment.

First, the overall configuration of a water treatment system in Example 1 will be described using FIG. 1. In FIG. 1, an odor sensor 1 is a sensor that measures the odor (odor level) due to odorous substances contained in raw water and outputs the measured odor. Note that in the following description, odor may be referred to as odor level.

In this embodiment, the odor sensor 1 is placed after the pretreatment section 2 that pretreats raw water, and measures the odor of the gas phase from which the pretreatment section 2 has recovered odorous substances from the raw water. Specifically, the pretreatment unit 2 performs processing to promote the movement of odorous substances in the raw water to the gas phase by stirring or heating the raw water, thereby improving the detection sensitivity of the odor sensor. The specific configuration of such odor sensor 1 and preprocessing section 2 is also disclosed in Patent Document 2, for example.

The water quality sensor 3 is a sensor that measures the water quality of raw water and outputs water quality data, including the turbidity, pH, water temperature, conductivity, alkalinity, chlorine demand, chromaticity, and TOC (Total Organic Carbon) of the raw water. carbon), E260 (ultraviolet absorbance), etc. The water quality data measured by the water quality sensor includes physical quantities that may be related to the concentration of musty odor substances, such as turbidity, pH, water temperature, conductivity, and alkalinity, as well as substances that are adsorbed to activated carbon, such as chromaticity, TOC, and E260. and related physical quantities. Among these, it is preferable to use at least the turbidity of raw water.

The external data input unit 4 is provided to obtain external data stored in an external device via a communication line such as the Internet. External data includes the amount and pattern of rainfall in the past or recent days upstream, the amount of solar radiation upstream, and the water level of rivers and reservoirs from which water is taken. That is, the external data is data other than water quality data measured by a water quality sensor owned by the equipment, and mainly includes data that affects the concentration of musty-smelling substances and turbid substances. Of these, it is recommended to use at least rainfall and solar radiation data.

The event data input section 5 is provided for inputting various data (event data) related to events that affect mold odor through operations by an operator or the like. This event data includes operating condition data that changes due to seasonal changes, data associated with upstream facility operations (for example, water discharge from dam reservoirs, opening of agricultural canals, plowing period in rice fields, etc.), and other data related to mold odor. These include various accidents that have an impact (for example, fuel flowing into rivers due to vehicle accidents, leakage of odorous substances from factory wastewater treatment, etc.). Of these, it is preferable to use at least the operating condition data.

In addition, in this embodiment, these event data are not part of the external data that is inputted from the outside via the Internet, etc., but are inputted by the operator's operation. It may be input as part of the data at any time.

The control unit 20 receives the odor level measured by the odor sensor 1, water quality data measured by the water quality sensor 3, external data obtained via the external data input unit 4, and event data obtained from the event data input unit 5. input. Then, using these data (information), a necessary activated carbon injection rate is calculated according to a control program stored in advance, and powdered activated carbon injection control is executed based on the activated carbon injection rate.

Specifically, the control unit 20 includes a storage unit that stores a control program, input data, arithmetic processing information, etc., and performs predetermined arithmetic processing using the input data, information, etc. according to the stored control program. and an output section that controls devices such as pumps and valves and displays guidance based on the results of the arithmetic processing. The control unit 20 having such a function can be realized by a known general computer. Note that in FIG. 1, the main functions of the control section 20 are shown as a block diagram in the control section 20 for easy understanding. That is, the control unit 20 in FIG. 1 functionally includes a mold odor estimation unit 6 and an activated carbon injection rate calculation unit 7.

The water treatment facility 10 is a facility for purifying raw water, and is entirely controlled by a control unit 20. Note that the control unit 20 is provided to control the entire water treatment equipment 10, but in the following, the control unit 20 calculates the activated carbon injection rate and controls the injection of powdered activated carbon based on this activated carbon injection rate. The explanation will focus on how to perform the activated carbon injection rate or display this activated carbon injection rate as guidance.

The water treatment equipment 10 in this embodiment includes a landing well 11 that stabilizes the water level of raw water and adjusts the amount of water, and a mixing pond 12 that stirs and uniformly disperses the injected agent such as a flocculant. In addition, this water treatment equipment 10 further includes a flocculation pond 13 that flocculates suspended solids in raw water into which a chemical such as a flocculant has been injected and generates flocs, and a sedimentation tank that removes flocs grown by flocculation treatment by sinking them to the bottom. It is equipped with a pond 14 and a filtration basin 15 for removing suspended matter that could not be removed in the settling basin. The chemical injection unit 16 contains chemicals (flocculants, powdered activated carbon, etc.) used for water treatment, and injects (injects) the chemicals into raw water according to control commands (control signals) from the control unit 20 or operations by the operator. . The powdered activated carbon made into a slurry is injected into the water landing well 11 by driving an activated carbon injection device included in the chemical injection unit 16 . Note that the water treatment equipment to which the present invention can be applied is not limited to the water treatment equipment shown in FIG. can also be applied.

Next, the operation of the water treatment system in Example 1 will be explained. In FIG. 1 , data representing the odor (odor level) of raw water measured by the odor sensor 1 is input to the control unit 20 . Further, water quality data measured by the water quality sensor 3 is input to the control unit 20. Further, external data from the external data input section 4 is also input to the control section 20 . Similarly, event data obtained from the event data input section 5 is also input to the control section 20. It is assumed that the odor data and water quality data are measured at predetermined time intervals required for control and input to the control unit 20.

The mold odor estimating unit 6 extracts input odor data, water quality data (turbidity, pH, conductivity, alkalinity, etc.) that may be related to the concentration of musty odor substances, and event data (such as water quality data that may affect mold odor). A "mold odor occurrence index P" which is the probability of occurrence of a mold odor is estimated using various data related to the event.

This mold odor occurrence index P can be estimated and calculated as follows. That is, for example, for each event data, external data, and measured data, coefficients (weighting) related to the occurrence of mold odor are prepared in advance by referring to past experience, etc., and the probability of each data contributing to the occurrence of mold odor is calculated. A mold odor occurrence index is calculated for each data to which each data is applied by applying the model (correlation formula), and their product or sum is defined as the "mold odor occurrence index." The calculation model and the coefficients of each data are stored in advance in a storage section within the control section 20. It is desirable to improve the accuracy of the correlation formula and weighting coefficients used to calculate the mold odor occurrence index by constantly reflecting the mold odor intensity and substance concentration determined by sensory tests and water quality analysis. It is also a good idea to prepare multiple formulas and tables depending on the pattern of seasons and weather conditions, and select and use formulas and coefficients suitable for the season and weather. Furthermore, if sufficient data on the presence/absence of mold odor/odor concentration and event/external/water quality data is accumulated, the mold odor occurrence index may be calculated using a statistical method for these data.

The activated carbon injection rate calculation unit 7 calculates odor data (measured data from the odor sensor 1), the musty odor generation index calculated by the musty odor estimating unit 6, and water quality data regarding substances adsorbed to activated carbon such as chromaticity and TOC. Calculate (compute) the activated carbon injection rate using

In general, injection of powdered activated carbon is basically unnecessary if no mold odor is occurring. Therefore, the activated carbon injection rate is calculated by determining whether or not a mold odor has occurred, and when it is determined that a musty odor has occurred. In the activated carbon injection rate calculation unit 7 in Example 1, the occurrence of mold odor is determined as follows.

First, the odor measured by the odor sensor 1 during normal times when no musty odor is generated is determined in advance, and this is stored in the storage section in the control section 20 as the reference odor Is that serves as a criterion for judgment. The odor of raw water varies depending on conditions such as season and rainfall, so for example, the average value of the odor from the last few points where mold odor has not occurred, or the value predicted by an empirical formula or statistically based on past fluctuation patterns. may be used as the reference odor Is. Next, the measured odor Ip measured by the odor sensor 1 and the reference odor Is are compared. If the measured odor Ip is larger than the reference odor Is, it is determined that some odor substance including a musty odor substance has increased. If Ip is smaller than the reference odor Is, it is determined that the increase in some odor substances including moldy odor substances is small.

In addition, if the raw water is not passed through the filter in the pretreatment unit 2, a correlation equation between the turbidity measurement data and the odor level measured by the odor sensor 1 is obtained in advance, and this correlation equation and the turbidity measurement data are obtained in advance. The odor derived from suspended solids may be estimated from the measurement data, and the estimated odor may be subtracted from the measured odor Ip.

Next, when the measured odor Ip is larger than the standard odor Is, the musty odor occurrence index P determined by the musty odor estimating section 6 is compared with the standard value Ps of musty odor occurrence, and the musty odor occurrence index P is determined. If it is equal to or higher than the reference value Ps, it is determined that mold odor has occurred or there is a high possibility that mold odor will occur. Note that the reference value Ps can be arbitrarily selected according to the judgment of the operator. When it is determined that activated carbon injection is necessary, arithmetic processing is performed to calculate the required activated carbon injection rate.

Specifically, the activated carbon injection rate is calculated as follows. First, the difference ΔI between the measured odor Ip used for judgment and the reference odor Is is determined. Assuming that this difference ΔI is correlated with the concentration of odorous substances including moldy odor substances, it is assumed that the difference ΔI is correlated with the concentration of odorous substances including moldy odor substances, and by using a correlation formula created in advance between the amount of powdered activated carbon consumed and the odor originating from the moldy odor substances, The "first activated carbon injection rate Mo" for removing odor substances can be calculated.

By the way, since raw water contains substances that consume activated carbon in addition to substances related to moldy odor, the amount of activated carbon consumed by these substances should be taken into consideration.

Therefore, in this example, the influence of substances that consume activated carbon is determined. In other words, by using water quality data related to substances that consume activated carbon (e.g. chromaticity, TOC, E260, etc.), we can determine the "second activated carbon injection rate" to compensate for the insufficient amount of activated carbon consumed in order to treat the mold odor below a predetermined mold odor level. Md” is calculated. This second activated carbon injection rate Md is determined by creating a correlation equation in advance between water quality data related to substances that consume activated carbon and the consumption amount of powdered activated carbon, and applying the actually measured water quality data related to substances that consume activated carbon to this correlation equation. It can be calculated by applying

By adding the first activated carbon injection rate Mo calculated to remove mold odor to the second activated carbon injection rate Md calculated in this way, the activated carbon injection rate Mt actually consumed can be determined. Note that the activated carbon injection rate actually consumed is referred to as the "required activated carbon injection rate."

In this way, the activated carbon injection rate calculation unit 7 calculates the activated carbon injection rate (required activated carbon injection rate) required to reduce the mold odor substance concentration to below a predetermined reference value as Mt (=Mo+Md). be able to.

The control unit 20 determines the amount of powdered activated carbon to be injected into the raw water based on the calculated required activated carbon injection rate Mt, and outputs the control signal to the chemical injection unit 13. The chemical injection unit 13 injects powdered activated carbon into the raw water based on this control signal (control command).

In this embodiment, the control unit 20 drives the chemical injection unit to automatically inject powdered activated carbon into raw water based on the calculated required activated carbon injection rate, but the present invention does not apply such a method. It is not limited to. That is, the control unit 20 calculates the required activated carbon injection rate, displays this required activated carbon injection rate, or the powdered activated carbon injection amount based on the required activated carbon injection rate on a display unit (not shown), and allows the operator to calculate the amount displayed on the display unit. The powdered activated carbon may be injected into the raw water by confirming the contents and operating the chemical injection unit.

Next, a procedure for calculating the activated carbon injection rate in the control unit 20 will be explained using the calculation processing flow shown in FIG. 2.

In FIG. 2, first, the calculations described with respect to the mold odor estimating section 6 described above are performed. That is, in step S01, a mold odor occurrence index P is calculated. Specifically, as described above, input event data, external data, and measurement data are used to apply a calculation model (correlation formula) of the probability that each data stored in advance contributes to mold odor generation. , the mold odor index P of the raw water is calculated by calculating the mold odor index of each data and finding the product or sum of the respective mold odor indexes.

In step S02, the odor sensor 1 measures the odor of the raw water extracted into the gas phase by the pretreatment unit 2.

In the next step S03, the pre-stored reference odor Is and the measured Ip are compared. The gas phase of the pretreated raw water contains organic matter derived from humus, soil, etc. even if it does not contain moldy odor substances, and is measured as an odor by the odor sensor 1. In step S03, if Ip>Is, the process advances to step S04, and if Ip≦Is, the process ends.

In the next step S04, it is determined whether the mold odor generation index P calculated in step S01 is equal to or higher than the mold reference value Ps. If the mold odor generation index P exceeds the reference value Ps, it is determined that mold odor is occurring or is likely to occur, and the process proceeds to step S05, where calculation processing of the required activated carbon injection rate is executed. If it is below the reference value, the process ends.

In the next step S05, the difference ΔI between the measured odor Ip and the reference odor Is is calculated, and the first activated carbon injection rate Mo is calculated using this ΔI. The first activated carbon injection rate Mo is calculated from a correlation equation with the consumption amount of powdered activated carbon created in advance, assuming that there is a correlation with the concentration of odor substances including moldy odor substances.

Next, in step S06, using the water quality data of substances that consume activated carbon such as chromaticity, TOC, and E260, a correlation equation between each water quality item and powdered activated carbon consumption that has been created in advance is used to determine whether substances other than odorous substances are The consumed second activated carbon injection rate Md is calculated.

Then, in step S07, the first activated carbon injection rate Mo obtained in step S05 and the second activated carbon injection rate Md obtained in step S06 are added to determine the actual amount of activated carbon injection necessary for removing the musty odor substance. The "required activated carbon injection rate Mt" is determined.

Furthermore, although not shown in FIG. 2, the control unit 20 determines the amount of powdered activated carbon to be injected based on the required activated carbon injection rate Mt calculated in this way, or injects powdered activated carbon into the raw water according to an operator's operation. Execute control to inject into.

FIG. 3 shows a conceptual diagram of the effects of this embodiment. The method of estimating a musty-smelling substance using the measurement value of the odor sensor and various data of this example is inferior to the sensory test or quantification by GC/MS, as it cannot discriminate the musty odor and the accuracy of the quantification is inferior. On the other hand, it can be quantified as an indirect odor indicator with little effort and at low cost.

According to the first embodiment of the present invention described above, it is possible to accurately determine (calculate) the activated carbon injection rate for removing moldy odor substances in raw water to an extent that humans cannot feel it, and the required activated carbon injection rate The injection of powdered activated carbon can be controlled based on. As a result, it is possible to prevent excessive use of powdered activated carbon while ensuring good quality of treated water. Thereby, operating costs can be reduced.

≪Example 2≫
Next, Example 2 of the present invention will be described. FIG. 4 discloses a flowchart showing the calculation processing procedure for the required activated carbon injection rate in the second embodiment.

The second embodiment basically has almost the same configuration as the first embodiment, and only partially differs from the first embodiment in the content of the calculation procedure. Therefore, in the explanation of the second embodiment using FIG. 4, the contents already explained in the first embodiment will be basically omitted, and the explanation will focus on the parts that are different from the first embodiment.

First, the configuration of the water treatment system in Example 2 is the same as that in FIG. 1 in Example 1. Therefore, illustration and description of the configuration of the water treatment system in Example 2 will be omitted.

In FIG. 4, in step S21, an operator measures the odor of raw water using a sensory test. At this time, calculation of the odor index by dilution is not essential.

In step S22, if the operator determines that there is a musty odor, the process proceeds to the next step. That is, the operator inputs the determination result of mold odor into the control unit 20 by operating an operation unit (for example, a keyboard) not shown. Based on this determination of the presence of mold odor, the control unit 20 calculates the required activated carbon injection rate. This calculation method is the same as in the first embodiment. That is, the processing of step S02 and steps S05 to S07 shown in FIG. 4 is the same calculation process as that shown in FIG. 2. The processing operations of each step in FIG. 4 have already been explained in detail using FIG. 2, so the explanation will be omitted.

As explained above, according to the second embodiment of the present invention, when an operator confirms a musty odor through a sensory test, the necessary powdered activated carbon injection rate can be calculated, and the powdered activated carbon injection can be performed. As a result, it is possible to suppress excessive use of powdered activated carbon, and operating costs can be reduced.

≪Example 3≫
Next, Example 3 of the present invention will be described.
Embodiment 3 basically has almost the same configuration as Embodiment 1, but in addition to the configuration of Embodiment 1, the pretreatment section 2 includes suspended matter in the raw water before stirring and heating. A filter is provided to remove the The other configurations and arithmetic processing are the same as those in FIGS. 1 and 2 in the first embodiment. Therefore, illustrations and explanations of the configuration and calculation processing of the water treatment system in Example 3 will be omitted.

In the case of raw water containing a large amount of turbidity, odor components (for example, earthy odor components) originating from the turbidity are extracted by stirring and heating in the pretreatment section 2, and are measured as an increase in the odor level. Odor components derived from turbidity are removed along with turbidity during the normal water purification process, and there is no need to inject powdered activated carbon, but since it does affect the odor level, it may be a factor in error in estimating musty odor substances. . In Example 3, the odor sensor 1 measures the odor level of raw water in which odor components extracted from suspended solids have been reduced by a filter provided in the pretreatment unit 2. As a result, the influence of components other than moldy odor on the odor level is suppressed, and a decrease in the estimation accuracy of moldy odor substances can be avoided.

In addition, if it is considered useful to monitor the condition of the raw water, including odor components derived from turbidity, the odor level is measured without using the same filter, and when estimating moldy odor substances, the turbidity The odor level derived from suspended solids may be estimated from the data and removed from the measured values.

As explained above, according to Example 3 of the present invention, it is possible to reduce error factors in the concentration of musty odor substances, and powder powder is Injection of activated carbon can be performed. As a result, it is possible to suppress excessive use of powdered activated carbon, and operating costs can be reduced.

1...Odor sensor, 2...Pre-treatment section, 3...Water quality sensor, 4...External data input section, 5...Event data input section, 6...Mold odor estimation section, 7...Activated carbon injection rate calculation section, 10...Water treatment equipment , 11... Water landing well, 12... Mixing basin, 13... Coagulation basin, 14... Sedimentation basin, 15... Filtration basin, 16... Chemical injection part, 20... Control part

Claims (16)

A water treatment system comprising water treatment equipment and a control unit for controlling the water treatment equipment,
an odor sensor that measures odor due to odorous substances contained in the raw water of the water treatment facility; a pre-treatment unit that processes the raw water measured by the odor sensor; a water quality sensor that measures water quality data of the raw water; an event data input section for inputting event data related to an event that affects the mold odor, and an external data input section that includes weather-related external data that affects the mold odor,
The control unit is a water treatment system that calculates a necessary activated carbon injection rate to reduce mold odor substances to a predetermined reference value or less based on the odor, the water quality data, the external data, and the event data. The water treatment system according to claim 1, wherein the control unit determines the amount of powdered activated carbon to be injected into the raw water based on the required activated carbon injection rate, and performs powdered activated carbon injection control. water treatment system. In the water treatment system according to claim 1, when the control unit determines that a musty odor has occurred, the control unit controls a first activated carbon for removing a musty odor substance based on a difference between the measured odor and a reference odor. Calculating an injection rate, calculating a second activated carbon injection rate commensurate with the consumption based on the water quality data related to substances that consume activated carbon, and adding the first activated carbon injection rate and the second activated carbon injection rate, A water treatment system characterized by determining the required activated carbon injection rate. 4. The water treatment system according to claim 3, wherein the determination of the occurrence of mold odor utilizes the results of a sensory test for determining the odor of raw water. In the water treatment system according to claim 3, the determination of the occurrence of mold odor is based on the mold odor occurrence index of the raw water using the inputted event data, the external data, and the water quality data related to the mold odor substance. A water treatment system characterized in that the measured odor is greater than or equal to a pre-stored reference odor, and the mold odor generation index is greater than or equal to a reference value. The water treatment system according to claim 5, wherein the water quality data used when calculating the mold odor occurrence index includes turbidity, water temperature, pH, electrical conductivity, and alkalinity. water treatment system. 4. The water treatment system according to claim 3, wherein the water quality data used when calculating the second activated carbon injection rate includes chromaticity and TOC. In the water treatment system according to any one of claims 1 to 7, the pretreatment section includes a filter that removes substances other than musty odor substances in the raw water, and the odor sensor A water treatment system characterized by measuring odor in the raw water that has passed through a filter. A method for controlling a water treatment system in which powdered activated carbon is extracted into raw water to reduce mold odor in water treatment equipment, the method comprising:
An odor sensor that measures odor due to odorous substances contained in the raw water of the water treatment facility, a pretreatment unit that processes the raw water measured by the odor sensor, and a water quality sensor that measures water quality data of the raw water. Ori,
below a predetermined standard value based on the odor measured by the odor sensor, the water quality data, event data related to events that affect the mold odor, and weather-related external data that affect the mold odor. A water treatment system control method that calculates the required activated carbon injection rate to reduce mold odor. In the water treatment system control method according to claim 9, the amount of powdered activated carbon to be injected into the raw water is determined based on the required activated carbon injection rate, and the powdered activated carbon injection is controlled so as to reach the amount of powdered activated carbon to be injected. A method for controlling a water treatment system, the method comprising: In the method for controlling a water treatment system according to claim 9, when it is determined that a mold odor has occurred, a first activated carbon for removing a mold odor substance based on a difference between the measured odor and a reference odor. Calculating an injection rate, calculating a second activated carbon injection rate commensurate with the consumption based on the water quality data related to substances that consume activated carbon, and adding the first activated carbon injection rate and the second activated carbon injection rate, A method for controlling a water treatment system, comprising determining the required activated carbon injection rate. 12. The method of controlling a water treatment system according to claim 11, wherein the determination of the occurrence of mold odor utilizes the results of a sensory test for determining the odor of raw water. The method for controlling a water treatment system according to claim 11,
The occurrence of a musty odor is determined by calculating a musty odor occurrence index of raw water using the input event data, the external data, and the water quality data related to the musty odor substance, and determining whether the measured odor is stored in advance. 1. A method for controlling a water treatment system, characterized in that the odor is greater than or equal to a standard odor, and the mold odor generation index is greater than or equal to a mold odor reference value. The method for controlling a water treatment system according to claim 13,
A method for controlling a water treatment system, wherein the water quality data used when calculating the mold odor occurrence index includes turbidity, water temperature, pH, electrical conductivity, and alkalinity. The method for controlling a water treatment system according to claim 11,
A method for controlling a water treatment system, wherein the water quality data used when calculating the second activated carbon injection rate includes chromaticity and TOC. In the method for controlling a water treatment system according to any one of claims 1 to 7,
A method for controlling a water treatment system, wherein the odor sensor measures the odor of the raw water after passing through a filter that removes substances other than mold odor in the raw water.

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