JP2019055406A - Coagulating sedimentation control device, coagulating sedimentation control method and computer program - Google Patents

Abstract

To provide a coagulating sedimentation control device, a coagulating sedimentation control method and a computer program, each enabling flocks excellent in settleability to be formed.SOLUTION: The coagulating sedimentation control device of the embodiment includes an image acquisition part, a coagulated condition acquisition part and a control part. The image acquisition part acquires an image of water to be treated from an imaging part imaging the water to be treated. The coagulated condition acquisition part acquires a coagulated condition of coagulated matter included in the water to be treated based on the image of the water to be treated which is acquired by the image acquisition part. The control part produces control information for controlling agitation conditions of the water to be treated to which a chemical for coagulating unnecessary objects as the coagulated matter is injected.SELECTED DRAWING: Figure 8

Description

  Embodiments described herein relate generally to a coagulation sediment control device, a coagulation sediment control method, and a computer program.

  In the fields of water and sewage, wastewater treatment, water supply, etc., water purification treatment is performed by various methods. Specifically, the purification treatment is a treatment for removing unnecessary substances such as solid matter and dissolved matter contained in water to be treated (hereinafter referred to as “water to be treated”). As typical methods for removing unnecessary substances from the water to be treated, sedimentation separation for separating unnecessary substances precipitated by gravity from the water to be treated, and pressure separation method for separating unnecessary substances in the water to be treated by bubbles, Examples include membrane separation in which filtration is performed using porous ceramics and resin, and an activated sludge method in which microorganisms prey on organic substances. Among such separation methods, the sedimentation separation and the pressure separation method generally use an agglomeration method in which an unnecessary substance is agglomerated with a drug and then separated. Among the above methods, sedimentation separation combined with the agglomeration method is called agglomeration precipitation method, and is widely used because it is easy to obtain a good purification effect by a relatively simple operation of adding a drug, stirring, and removing a precipitate. .

  In the water purification treatment by the coagulation sedimentation method, the sedimentation property of unnecessary substances aggregated by the chemical (hereinafter referred to as “floc”) depends on the aggregation state of the floc. And even if it is a case where the same operation is performed, the aggregation state of a floc changes with kinds of the unnecessary object used as removal object. For this reason, the conventional coagulation sedimentation method may not always form flocs with good sedimentation properties.

JP 2005-241338 A

  The problem to be solved by the present invention is to provide a coagulation / precipitation control device, a coagulation / precipitation control method, and a computer program capable of forming a floc with better sedimentation.

  The coagulation sedimentation control device of the embodiment includes an image acquisition unit, an aggregation state acquisition unit, and a control unit. An image acquisition part acquires the image of the said to-be-processed water from the imaging part which images to-be-processed water. The aggregation state acquisition unit acquires the aggregation state of the aggregates contained in the water to be treated based on the image of the water to be treated acquired by the image acquisition unit. The control unit controls the stirring condition of the water to be treated into which a chemical for aggregating an unnecessary substance as the aggregate is injected based on the aggregation state of the aggregate acquired by the aggregation state acquisition unit. Control information is generated.

The figure which shows the specific example of the coagulation sedimentation apparatus which implement | achieves a general coagulation sedimentation process. Schematic which shows the outline | summary of control of the coagulation sedimentation apparatus in 1st Embodiment. The figure which shows the specific example of the method of measuring the light absorbency of the to-be-processed water which flows through the flow cell. The functional block diagram which shows the function structure of the coagulation sedimentation control apparatus of 1st Embodiment. The figure which shows the specific example of the change of the light absorbency of to-be-processed water in the aggregation process. Schematic which shows the outline | summary of control of the coagulation sedimentation apparatus in 2nd Embodiment. The figure which shows the specific example of the method of imaging the to-be-processed water which flows through the flow cell. The functional block diagram which shows the function structure of the coagulation sedimentation control apparatus of 2nd Embodiment. The figure which shows the specific example of the image by which the flock was imaged. The figure which shows the specific example of the image by which the flock was imaged. The figure which shows the specific example of the image by which the flock was imaged. The figure which shows the specific example of the image by which the flock was imaged.

  Hereinafter, a coagulation sedimentation control device, a coagulation sedimentation control method, and a computer program according to embodiments will be described with reference to the drawings.

(Outline)
In the coagulation precipitation method, an inorganic compound such as an aluminum salt or an iron salt or an organic compound in which a functional group having a positive or negative charge is introduced into an organic polymer such as polyacrylamide is used as the coagulant. These flocculants (drugs) have the effect of aggregating unnecessary substances in the water to be treated into flocs (aggregates) and forming flocs larger. Such agglomeration treatment is performed in various water treatment facilities. For example, in a water purification plant, sand and clay-like soil components, plant fragments, plankton such as algae, and polymer lysate that causes coloring are targeted for removal. In the sewage treatment plant, a coagulation treatment is performed to improve the dewaterability of sludge. Further, in factory wastewater treatment, a wide variety of unnecessary materials discharged from various factories are to be removed.

  As described above, in spite of a wide variety of aggregation processing targets, there are currently relatively few patterns of processing methods. For example, in the agglomeration treatment at a water purification plant, an inorganic aluminum salt such as PAC (polyaluminum chloride) or sulfated clay is injected as a flocculant into the water to be treated, and two-stage agitation is performed: rapid agitation and slow agitation. To form a flock. In addition, the coagulation treatment in sewage treatment and factory wastewater treatment uses a polymer coagulant in which a functional group having a positive or negative charge is introduced into an organic polymer such as polyacrylamide in addition to the above inorganic coagulant. Although it is different, the point that a floc is formed by agitation after injection of the drug is the same as the coagulation treatment in the water purification plant.

  Conventionally, in such a relatively simple process, the injection amount and pH control method of the drug according to the removal target, the adjustment method of the functional group amount and molecular weight of the drug, etc. are the technology and know-how in water treatment engineering. It has become. And the evaluation of the state of the formed floc has conventionally been performed with an emphasis on the size of the floc. The reason why the size of the floc is used as an evaluation index is that the following Stokes equation is used as a basic rule for evaluating the floc sedimentation.

  In equation (1), v is the terminal velocity, D is the particle diameter, ρa is the specific gravity of the particle, ρb is the specific gravity of the liquid, g is the acceleration of gravity, and η is the viscosity of the fluid. From formula (1), it can be seen that the larger the particle size, the greater the sedimentation rate and the higher the sedimentation property. That is, it can be said that the purpose of the aggregation treatment is to form a larger floc. For this reason, conventionally, with respect to the formation state of flocs, evaluation has been made with emphasis on the size of flocs. However, this evaluation concept does not place importance on the specific gravity of the particles. This is because the substance to be removed generally has a large specific gravity (1.4 to 2.7 in the case of mud and soil components), and it easily forms from the water to be treated by forming a large flock. This is because they can be separated.

  However, when fine particles having poor sedimentation properties such as colloidal particles are to be removed, there is a possibility that a floc having sufficient sedimentation properties cannot be formed by a general aggregation method. As a result, a lot of chemicals are required for the formation of flocs, the sedimentation of the formed flocs is poor and it takes time to separate, the agglomeration reaction itself takes time, and a large water tank is required to secure a long residence time. Problems such as an increase in the size of equipment occur.

  In order to solve such a problem, the aggregation control device of the embodiment controls the aggregation process based on the absorbance of the water to be treated or the shape of the floc in addition to the size of the floc. Hereinafter, the aggregation control device of the embodiment will be described in detail.

(First embodiment)
FIG. 1 is a diagram showing a specific example of a coagulation sedimentation apparatus for realizing a general coagulation sedimentation process.
The coagulation sedimentation apparatus 100 includes a storage tank 110, a first coagulation tank 120, a drug storage tank 130, a drug injection pump 140, a stirrer 150, a second coagulation tank 160, a stirrer 170, and a sedimentation tank 180. The storage tank 110, the first flocculation tank 120, the second flocculation tank 160, and the sedimentation tank 180 are installed adjacent to each other as shown in the figure, and a flow path (not shown) for transporting water to be treated between the water tanks. ) Is provided. The water stored in the storage tank 110 is transported in the order of the first coagulation tank 120, the second coagulation tank 160, and the sedimentation tank 180 by using a height difference (hereinafter referred to as “head difference”), a pump, or the like. The

  The storage tank 110 is a water tank for storing the water to be treated. The first flocculation tank 120 is a water tank for putting a chemical into the water to be treated and causing unnecessary substances to flocculate. The medicine storage tank 130 is a water tank that stores a medicine that aggregates unnecessary substances. The drug injection pump 140 is a pump that injects the drug stored in the drug storage tank 130 into the first aggregation tank 120. In addition to these agents, the first flocculation tank 120 may be added with acids such as hydrochloric acid and sulfuric acid, and alkalis such as slaked lime and caustic soda as a pH adjuster for promoting floc formation.

  The stirrer 150 stirs the water to be treated that flows into the first flocculation tank 120. The stirrer 150 rotates the stirring blade 152 by driving the motor 151 to uniformly mix the water to be treated and the chemical. The stirring by the stirrer 150 is generally called a rapid stirring process, and has an effect of increasing the probability of collision between the drug and the suspended particulate solid body while accelerating the diffusion of the flocculant. As a result, the sol component contained in the flocculant gels while being combined with the solid matter in the water to be treated, and floc S1 is formed.

  The residence time of the water to be treated in the first flocculation tank 120 varies depending on the case, but it is generally taken, for example, for about 1 to 20 minutes. The floc formed in the first agglomeration tank 120 has a size of about several tens of μm and is very fine and poorly settled.

  The second flocculating tank 160 is a water tank for growing the floc S1 formed in the first flocculating tank 120 into a larger floc S2.

  The stirrer 170 stirs the water to be treated that flows into the second flocculation tank 160. The stirrer 170 stirs the water to be treated by rotating the stirring blade 172 by driving the motor 171. Agitation by the agitator 170 has an effect of causing the flocs S1 to collide with each other. In general, the stirrer 170 stirs the water to be treated with a gentle stirring strength compared to the stirrer 150. As a result, the fine flocs formed in the first agglomeration tank 120 collide with or combine with surrounding flocs in a gentle stirring, and gradually become larger flocs. The residence time of the water to be treated in the second flocculation tank 160 varies depending on the case, but it is generally about 10 minutes to 1 hour. In FIG. 1, the coagulation sedimentation apparatus 100 is configured to perform mechanical stirring by the stirrer 170, but may be configured to perform stirring by a flow using a bypass flow path.

  The sedimentation tank 180 is a water tank for causing the floc S2 formed in the second aggregation tank 160 to settle. In the sedimentation tank 180, flocs are separated from the water to be treated by gravity sedimentation due to the specific gravity difference. In order to increase the separation speed, the sedimentation tank 180 may be provided with auxiliary means such as an inclined plate or a sludge blanket. The coagulation sedimentation apparatus 100 acquires the water to be treated from which unnecessary substances have been removed (hereinafter referred to as “treated water”) by obtaining the supernatant liquid of the water to be treated in which unnecessary substances have precipitated in the sedimentation tank 180.

FIG. 2 is a schematic diagram showing an outline of control of the coagulation sedimentation apparatus in the first embodiment.
In FIG. 2, a broken line arrow indicates that a part of the water to be treated is separated from the coagulation sedimentation apparatus 100. The sorting flow path 200 is a diagram schematically showing a flow path of water to be treated separated from the coagulation sedimentation apparatus 100. A flow cell 210 provided in the middle of the sorting flow path 200 is a conduit for enabling imaging of the treated water that has been sorted. A part of the flow cell 210 is made of a transparent material such as glass, and is configured such that the water to be treated flowing therein can be imaged. Water to be treated flowing through the sorting channel 200 flows into the flow cell 210 from the inlet 211 and flows out from the outlet 212 to the sorting channel 200. The water to be treated may be collected from any one of the first flocculation tank 120, the second flocculation tank 160, and the settling tank 180, and may be collected from any part of each water tank. However, in consideration of the time delay in the control, the inspection at the earliest possible time is desirable. Therefore, in this embodiment, it is assumed that the water to be treated is separated from the first coagulation tank 120.

  The absorbance measurement device 300 measures the absorbance of the water to be treated flowing through the flow cell 210. The absorbance measuring device 300 continuously acquires the absorbance of the water to be treated. The absorbance measuring apparatus 300 outputs absorbance information indicating the measured absorbance to the aggregation and precipitation control apparatus 1.

  The coagulation sedimentation control device 1 acquires absorbance information from the absorbance measurement device 300. The coagulation sedimentation control device 1 acquires the aggregation state of flocs in the water to be treated based on the absorbance indicated by the absorbance information. The coagulation sedimentation control device 1 generates control information for controlling the coagulation process by the coagulation sedimentation device 100 based on the acquired aggregation state, and outputs the control information to the coagulation sedimentation device 100.

FIG. 3 is a diagram showing a specific example of a method for measuring the absorbance of the water to be treated flowing through the flow cell 210.
A circle in the flow cell 210 in FIG. 3 represents a floc in the water to be treated. The water to be treated collected from the coagulation sedimentation apparatus 100 flows into the flow cell 210 through the sorting flow path. The light source 310 irradiates the flow cell 210 with light having a specific wavelength. For example, the light source 310 is an LED (Light Emitting Diode). The absorbance measuring apparatus 300 measures the absorbance of the water to be treated by measuring the light transmitted through the flow cell 210 among the light irradiated by the light source 310. When a general light source such as a halogen lamp or a xenon lamp is used as the light source 310, the light source 310 may be configured to extract light having a specific wavelength using a spectroscopic unit such as a spectroscope or a band pass filter. In addition, when using light of a plurality of wavelengths, the light source 310 may be configured to switch between a plurality of light sources that emit only light of a specific wavelength, or to extract light of a plurality of wavelengths using the spectrometer. It may be configured, or may be configured to switch a plurality of filters that transmit different wavelengths. Thus, as long as the light absorbency of the to-be-processed water which flows through the flow cell 210 can be measured, the light absorbency measuring apparatus 300 and the light source 310 may be what kind of structure.

FIG. 4 is a functional block diagram showing a functional configuration of the coagulation sedimentation control apparatus of the first embodiment.
The coagulation sedimentation control device 1 includes a CPU (Central Processing Unit) connected via a bus, a memory, an auxiliary storage device, and the like, and executes a control program. The coagulation sedimentation control device 1 functions as an apparatus including an absorbance acquisition unit 11, an aggregation state acquisition unit 12, and a control information generation unit 13 by executing a control program. Note that all or a part of each function of the coagulation / precipitation control apparatus 1 may be realized by using hardware such as ASIC (Application Specific Integrated Circuit), PLD (Programmable Logic Device), or FPGA (Field Programmable Gate Array). . The control program may be recorded on a computer-readable recording medium. The computer-readable recording medium is, for example, a portable medium such as a flexible disk, a magneto-optical disk, a ROM, a CD-ROM, or a storage device such as a hard disk built in the computer system. The control program may be transmitted via a telecommunication line.

  The absorbance acquisition unit 11 acquires absorbance information indicating the absorbance of the water to be treated collected from the coagulation sedimentation device 100 from the absorbance measurement device 300. The absorbance acquisition unit 11 outputs the acquired absorbance information to the aggregation state acquisition unit 12.

  The aggregation state acquisition unit 12 acquires the aggregation state of flocs based on the absorbance information acquired by the absorbance acquisition unit 11.

FIG. 5 is a diagram illustrating a specific example of the change in the absorbance of the water to be treated in the aggregation process.
FIG. 5 shows an absorption spectrum when a 100 μL / L ink solution is aggregated in the neutral region using PAC. In FIG. 5, the horizontal axis represents the wavelength of light irradiated to the water to be treated, and the vertical axis represents the absorbance measured for light of each wavelength. Further, the plurality of series shown in FIG. 5 represent the relationship between the wavelength and the absorbance at each elapsed time indicated by the legend on the right side of the figure. Here, the flocculant was injected at the start of the aggregation process (0 min in the figure), and stirring was started at the same timing. Further, the stirring here was rapid stirring at 150 rpm (circumferential speed of about 0.6 m / s) for the first 11 minutes, and then slow stirring at 50 rpm (circumferential speed of about 0.2 m / s).

  In general, unnecessary substances to be removed by coagulation sedimentation are particles having a diameter of about 0.01 μm to 100 μm. Larger particles can be separated by natural sedimentation without agglomeration. Particles having a particle size of 1000 nm or less are called colloids and do not settle due to gravity due to the influence of Brownian motion. The ink solution is an example of such a colloid and has a particle size of about 100 nm. In general, light having a wavelength of about 200 nm to 1000 nm (ultraviolet to near infrared) is used for measuring the absorbance. How the light irradiated to the water to be treated is scattered by the particles in the water to be treated depends on the magnitude relationship between the wavelength of the irradiated light and the particle diameter of the particles in the water to be treated.

In general, the influence of light wavelength and particle size on absorbance can be explained as follows.
First, when the particle diameter is sufficiently large with respect to the wavelength of light, light scattering can be approximated geometrically. In this case, there is almost no influence of scattered light on the absorbance, and the absorbance has a high correlation with the concentration of particles. Therefore, in such a case, the aggregation state can be determined by measuring the absorbance using light having a long wavelength such as red light.

  Next, when the particle diameter is approximately the same as the wavelength of light, Mie scattering is dominant in light scattering. In this case, although the influence of scattered light on the absorbance increases, the absorbance has a certain degree of correlation with the particle concentration. Therefore, in such a case, as in the case where the particle diameter is sufficiently large with respect to the wavelength of light, the aggregation state can be determined by measuring the absorbance using long-wavelength light such as red light.

  Next, when the particle diameter is sufficiently small with respect to the wavelength of light, Rayleigh scattering is included in the light scattering. In this case, the influence of scattered light on the absorbance increases, and the correlation between the absorbance and the concentration of particles decreases. Therefore, in such a case, it is difficult to determine the aggregation state only by measuring the absorbance using long-wavelength light such as red light.

Such a relationship between the wavelength and the particle diameter is also apparent from FIG. For example, in the case of FIG. 5, in the long wavelength region, the change in absorbance with respect to the change in the aggregation state is small. That is, in the long wavelength region, this indicates that the absorbance depends on the absorption coefficient and concentration of the particles. On the other hand, in the short wavelength region, the change in absorbance with respect to the change in the aggregation state is large. For example, it can be seen that the absorbance does not change for 3 minutes after the start of stirring, and the absorbance decreases as aggregation proceeds after 5 minutes. Then, it can be seen that the decrease in absorbance almost converges for 11 minutes after the start, and that the change in absorbance is small with subsequent slow stirring. That is, in the short wavelength region, it can be seen that the influence of the particle size on the absorbance changes according to the aggregation state. What is particularly characteristic is that the absorbance decreases from 0.5 to 0.2 at a wavelength of 270 nm. Therefore, the target aggregation state can be controlled by the absorbance by measuring in advance such a characteristic change in absorbance as an index representing the change in aggregation state.
For example, an index value using such absorbance is defined by the following equation (2).

  In the formula (2), A0 represents the raw water absorbance, and A1 represents the absorbance in the coagulation tank. The raw water absorbance is the absorbance of the water to be treated in the initial state before the aggregation treatment is performed. A is an index value expressed as a ratio of the absorbance of the water to be treated during the flocculation process to the absorbance of the raw water, and is a value that decreases as the floc aggregation proceeds. For example, in the case of the example of FIG. 5, such an index value A is calculated based on the absorbance at a wavelength of 270 nm measured in advance. Then, the calculated index value A is set in advance in the control information generation unit 13 as a control target value. Specifically, an index value A is calculated in advance, where the absorbance at time t = 0 [min] (that is, the raw water absorbance) is A0, and the absorbance at time t = 11 [min] is A1. .

  On the other hand, the aggregation state acquisition unit 12 calculates the index value A based on the absorbance measured during the aggregation process. The aggregation state acquisition unit 12 outputs the acquired index value A to the control information generation unit 13 as aggregation state information indicating the aggregation state at that time.

  The control information generation unit 13 generates control information for controlling the coagulation sedimentation apparatus 100 based on the aggregation state information acquired by the aggregation state acquisition unit 12. Specifically, the control information generation unit 13 generates control information for controlling the drug injection amount or the stirring condition based on a preset control target value and the current aggregation state. For example, the coagulation / precipitation control device 1 stores in advance an appropriate drug injection amount corresponding to the ratio between the control target value and the current coagulation state. In this case, the control information generation unit 13 generates control information for controlling the coagulation / precipitation control device 1 so as to achieve a drug injection amount or a stirring condition corresponding to the ratio between the control target and the aggregation state. For example, if the current index value is higher than the target index value, the control information generation unit 13 determines that the coagulant is insufficient, and generates control information that increases the injection amount of the coagulant. In the opposite case, it is determined that the coagulant is excessive, and control information for reducing the injection amount of the coagulant is generated. Further, the control information generation unit 13 may generate control information for controlling the stirring conditions (strength or time) of the stirrer instead of the amount of the flocculant injected.

  In addition, when the absorbance is used to acquire the aggregation state as described above, for example, a phenomenon called drift may occur in which the absorbance measurement value increases as a whole due to, for example, floc fragments adhering to the flow cell. is there. In such a case, in addition to the measurement value of the wavelength of 270 nm described above, for example, if a measurement value of a wavelength of 500 nm longer than 270 nm is acquired in advance, the following equations (3), (4), and ( The influence of drift can be eliminated by normalization using the statistical values obtained in 5).

  In Expression (3), A0 represents the raw water absorbance measured by the first wavelength, and B0 represents the raw water absorbance measured by the second wavelength. For example, the first wavelength is 270 nm, and the second wavelength is longer than the first wavelength, for example, 500 nm. In Formula (4), A1 represents the absorbance in the aggregation tank measured by the first wavelength, and B1 represents the absorbance in the aggregation tank measured by the second wavelength.

  In this case, C0 (−1 ≦ C0 ≦ 1) in the formula (3) is an index value indicating the amount of unnecessary substances contained in the raw water, and C1 decreases from the initial value C0 as the stirring time elapses. Go. That is, C1 in the formula (4) is an index value of the aggregation state. Therefore, when C1 = C is obtained as the control target value in advance, the amount of medicine and the stirring intensity can be controlled by comparing the measured C1 with the target value C. For example, when the measured value C1 is larger than the target value C, it is determined that the amount of medicine is insufficient or the stirring strength is insufficient, and the amount of medicine input is increased or the stirring strength is increased. That's fine. When the measured value C1 is smaller than the target value C, it is determined that the amount of medicine is excessive or the stirring strength is excessive, and the amount of medicine input may be reduced or the stirring strength may be weakened. .

  Formula (5) is an example of a formula for determining a drug injection rate and a control value for stirring intensity in accordance with the change in the index value described above. In Expression (5), k and α are coefficients that uniquely determine the control value according to the measured value C1 of the index value and the target value C of the index value. These coefficients are set according to the properties and characteristics of the aggregation processing system to be controlled.

In the case of a continuous system in which the quality of the raw water continuously changes, the control target may be switched according to the change in the quality of the raw water. In general, in the water treatment system, the quality of water to be treated sent to the coagulation sedimentation apparatus 100 is measured using an index such as turbidity. Therefore, the relationship between the turbidity of the raw water and the control target value is acquired and set in the control information generation unit 13 in advance.
The control information generation unit 13 generates control information based on the control target according to the turbidity of the raw water and the current aggregation state. By generating the control information in this way, the coagulation sedimentation control device 1 can make the coagulation sedimentation device 100 correspond to a continuous system.

  The flocculation / precipitation control apparatus 1 according to the first embodiment configured as described above acquires the floc flocculation state based on the absorbance of the water to be treated. The absorbance of the water to be treated shows a significant change in light having a specific wavelength according to the properties of the water to be treated. Therefore, based on the absorbance using light having such a specific wavelength, it is possible to evaluate the aggregated state with higher accuracy even for an unnecessary material having a small particle diameter such as colloidal particles. By performing control based on such absorbance, the coagulation sedimentation control apparatus 1 can control the coagulation sedimentation apparatus 100 so that flocs with better sedimentation properties are formed.

(Second Embodiment)
FIG. 6 is a schematic diagram showing an outline of control of the coagulation sedimentation apparatus in the second embodiment.
The coagulation / sediment control apparatus 1 of the first embodiment determined the floc aggregation state based on the absorbance of the water to be treated. On the other hand, the coagulation sedimentation control apparatus 1a of 2nd Embodiment judges the aggregation state of a flock based on the image by which the to-be-processed water was imaged.
The imaging device 400 (imaging unit) acquires an image of the water to be treated sorted from the coagulation sedimentation device 100 by imaging the flow cell 210. The imaging device 400 outputs the acquired image of the water to be treated to the coagulation sedimentation control device 1.

  The coagulation sedimentation control device 1 acquires the floc aggregation state based on the image of the water to be treated acquired by the imaging device 400. The coagulation sedimentation control device 1 generates control information for controlling the coagulation sedimentation control device 1 so that the floc aggregation state becomes a better state based on the acquired aggregation state. The coagulation sedimentation control device 1 outputs the generated control information to the coagulation sedimentation device 100.

FIG. 7 is a diagram illustrating a specific example of a method for imaging the water to be treated flowing through the flow cell 210.
The water to be treated collected from the coagulation sedimentation apparatus 100 flows into the flow cell 210 through the sorting flow path. The light source 310 irradiates the flow cell 210 with light. The imaging device 400 acquires an image of the treated water that has been collected by imaging the flow cell 210 illuminated by the light source 310. The imaging device 400 outputs the acquired image of the water to be treated to the coagulation sedimentation control device 1.

FIG. 8 is a functional block diagram showing a functional configuration of the coagulation sedimentation control device of the second embodiment.
The coagulation sedimentation control device 1a is provided with an image acquisition unit 14 instead of the absorbance acquisition unit 11, a point provided with an aggregation state acquisition unit 12a instead of the aggregation state acquisition unit 12, and control information generation instead of the control information generation unit 13. It differs from the coagulation sedimentation control apparatus 1 of 1st Embodiment by the point provided with the part 13a.
The image acquisition unit 14 acquires an image obtained by imaging the water to be treated from the imaging device 400. The image acquisition unit 14 outputs the acquired image of the water to be processed to the aggregation state acquisition unit 12a.

  The aggregation state acquisition unit 12a acquires the aggregation state of flocs based on the image of the water to be treated acquired by the image acquisition unit 14. Specifically, the aggregation state acquisition unit 12a identifies the outline of the flock from the image. The aggregation state acquisition unit 12a acquires a shape factor indicating the shape of the floc based on the identified floc outline. For example, the shape factor may be represented by roundness, fractal order, or the like, or simply represented by size (for example, area). The flock has a better settling property as the roundness is higher, and has a better settling property as the fractal order is lower. Moreover, the larger the size, the better the settling property. It should be noted that any existing image recognition technique may be used as a method for identifying a flock from an image. The aggregation state acquisition unit 12a outputs the acquired floc shape factor to the control information generation unit 13a as aggregation state information indicating the aggregation state at that time.

  In order to identify the outline of the flock from the image, the flock needs to be imaged so as to have an appropriate size in the image. Therefore, the imaging apparatus 400 needs to appropriately set the magnification of the lens, the resolution of the image sensor, the optical size, and the like according to the subject. For example, when the floc passing through the flow cell 210 has a size of several tens of μm, the imaging range may be about several hundred μm to several mm square, and a lens having a magnification of several times to several hundred times may be used. Further, when it is difficult to obtain the floc outline, the floc can be imaged more clearly by using a phase contrast microscope, coaxial incident light, or the like as necessary.

The control information generation unit 13a generates control information for controlling the coagulation sedimentation apparatus 100 based on the aggregation state information acquired by the aggregation state acquisition unit 12a. Specifically, the control information generation unit 13 generates control information for controlling the drug injection amount or the stirring condition based on a preset control target value and the current aggregation state. For example, when the floc is not formed in a sufficiently large size, control information that increases the amount of medicine injected may be generated.
In addition, if the floc is not in a sufficiently good shape, control information that increases the strength of rapid stirring may be generated. Further, the control information generation unit 13a may generate control information for controlling the stirring time instead of the stirring intensity.

9 to 12 are diagrams illustrating specific examples of images in which flocs are captured.
Each of FIGS. 9 to 12 is an image obtained when 100 μL / L of the ink ink aqueous solution is aggregated in the neutral region using PAC. In addition, the several image in each figure is an image which imaged multiple flocs formed in the same coagulation sedimentation process.

  FIG. 9 shows a case where a flat blade stirrer is used for stirring, and after rapid stirring at 150 rpm (circumferential speed of about 0.6 m / s), slow stirring is performed at 50 rpm (circumferential speed of about 0.2 m / s). It is the image of the flock imaged. As is apparent from the figure, the floc in this case is irregularly shaped and a relatively large floc is formed.

  FIG. 10 shows slow stirring at 50 rpm (peripheral speed of about 0.2 m / s) using a flat blade stirrer after rapid stirring at 1000 rpm (peripheral speed of about 1.5 m / s) using a screw blade stirrer. It is the image of the flock image | photographed when performing. As is apparent from the figure, the floc is an irregular and irregular shape as in FIG. 9, and a relatively large floc is formed.

  FIG. 11 shows slow stirring at 50 rpm (peripheral speed of about 0.2 m / s) using a flat blade stirrer after rapid stirring at 3000 rpm (peripheral speed of about 4.5 m / s) using a screw blade stirrer. It is the image of the flock image | photographed when performing. As is apparent from the figure, the flock in this case has a rounded outline, unlike the cases of FIGS. In this case, a relatively small floc is formed.

  FIG. 12 shows that after rapid stirring at 6000 rpm (circumferential speed of about 9 m / s) using a screw blade stirrer, slow stirring at 50 rpm (circumferential speed of about 0.2 m / s) using a flat blade stirrer is performed. In this case, the image is captured. As is apparent from the figure, the shape of the flock in this case is closer to that in FIG. 9 than in FIGS. 7 and 8, and the outline is rounded. In this case, a relatively large floc is formed.

  The sedimentation properties of flocs obtained by such a coagulation sedimentation treatment were good in the order of FIG. 10, FIG. 9, FIG. 8, and FIG. That is, when the stirring intensity of rapid stirring was increased, a result that flocs with good separability could be formed was obtained.

  Thus, the shape and size of the floc greatly affects the sedimentation of the floc. Therefore, the aggregation state acquisition unit 12a acquires a shape factor indicating the shape and size of such a flock from an image obtained by imaging the water to be treated. The coagulation sedimentation control device 1a of the embodiment controls the stirring conditions of the coagulation sedimentation device 100 based on such a shape factor. By such control, the coagulation sedimentation apparatus 100 can form flocs with better sedimentation properties.

  According to at least one embodiment described above, the injection amount of the medicine or the medicine injected into the water to be treated is injected based on the floc aggregation state in the water to be treated acquired based on the image or the absorbance. By having a control unit that controls the agitation conditions of the water to be treated, flocs with better sedimentation can be formed.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the spirit of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are also included in the invention described in the claims and the equivalents thereof.

DESCRIPTION OF SYMBOLS 1,1a ... Aggregation precipitation control apparatus, 11 ... Absorbance acquisition part, 12, 12a ... Aggregation state acquisition part, 13, 13a ... Control information generation part, 14 ... Image acquisition part, 100 ... Aggregation precipitation apparatus, 110 ... Storage tank, DESCRIPTION OF SYMBOLS 120 ... 1st coagulation tank, 130 ... Drug storage tank, 140 ... Drug injection pump, 150 ... Agitation machine, 151 ... Motor, 152 ... Agitation blade, 160 ... 2nd aggregation tank, 170 ... Agitation machine, 171 ... Motor, 172 ... Agitation Wings, 180 ... precipitation tank, 200 ... sort flow path, 210 ... flow cell, 211 ... inlet, 212 ... outlet, 300 ... absorbance measuring device, 310 ... light source, 400 ... imaging device

Claims (6)

An image acquisition unit that acquires an image of the water to be processed from an imaging unit that images the water to be processed;
Based on the image of the water to be treated acquired by the image acquisition unit, an aggregation state acquisition unit that acquires the aggregation state of the aggregates contained in the water to be treated;
Control information for controlling the stirring condition of the water to be treated infused with a chemical for aggregating an unnecessary substance as the aggregate based on the aggregate state of the aggregate acquired by the aggregation state acquisition unit. A control unit to generate;
A coagulation sedimentation control device. The aggregation state acquisition unit identifies the aggregate from the image of the water to be treated, acquires the identified shape of the aggregate as the aggregation state,
The control unit generates the control information based on the shape of the aggregate.
The coagulation sedimentation control apparatus according to claim 1. The stirring condition is stirring intensity in rapid stirring.
The coagulation sedimentation control apparatus according to claim 1 or 2. The stirring condition is a stirring time in rapid stirring.
The coagulation sedimentation control apparatus according to any one of claims 1 to 3. An image acquisition step of acquiring an image of the water to be treated from an imaging unit that images the water to be treated;
Based on the image of the water to be treated acquired in the image acquisition step, an aggregation state acquisition step of acquiring the aggregation state of the aggregates contained in the water to be treated;
Control information for controlling the stirring condition of the water to be treated infused with a chemical for aggregating an unnecessary substance as the aggregate based on the aggregate state of the aggregate acquired in the aggregation state acquisition step. A control step to generate;
A coagulation sedimentation control method comprising: An image acquisition step of acquiring an image of the water to be treated from an imaging unit that images the water to be treated;
Based on the image of the water to be treated acquired in the image acquisition step, an aggregation state acquisition step of acquiring the aggregation state of the aggregates contained in the water to be treated;
Control information for controlling the stirring condition of the water to be treated infused with a chemical for aggregating an unnecessary substance as the aggregate based on the aggregate state of the aggregate acquired in the aggregation state acquisition step. A control step to generate;
A computer program for causing a computer to execute.