JP7003165B2 - Coagulation treatment system, coagulation treatment method, computer program and coagulation treatment control device - Google Patents

Description

Embodiments of the present invention relate to a coagulation treatment system, a coagulation treatment method, a computer program, and a coagulation treatment control device.

In fields such as water and sewage, wastewater treatment, and water supply, water purification treatment is carried out by various methods. The purification treatment is specifically referred to as water to be treated (hereinafter referred to as "water to be treated").
) Is a process for removing unnecessary substances such as solids and dissolved substances. Typical methods for removing unwanted substances from the water to be treated include sedimentation separation, which separates unwanted substances settled by gravity from the water to be treated, and pressure separation, which separates unwanted substances in the water to be treated by bubbles. Examples include membrane separation by filtering using porous ceramics and resin, and activated sludge method in which microorganisms prey on organic substances. Among such separation methods, in the sedimentation separation and the pressure separation method, the aggregation method in which unnecessary substances are aggregated by a chemical and then separated is generally used. Among the above methods, the sedimentation separation combined with the agglutination method is called the agglutination sedimentation 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 an unnecessary substance (hereinafter referred to as "flock") aggregated by a chemical agent depends on the coagulation state of the flocs. The aggregated state of the flocs differs depending on the type of unnecessary material to be removed even when the same operation is performed. Therefore, in the conventional coagulation sedimentation method, it may not always be possible to form flocs having good sedimentation properties.

Japanese Unexamined Patent Publication No. 2005-241338

An object to be solved by the present invention is to provide a coagulation treatment system, a coagulation treatment method, a computer program and a coagulation treatment control device capable of forming flocs having better sedimentation property.

The coagulation treatment system of the embodiment includes a drug injection pump that injects a drug for aggregating particles in the water to be treated into the water to be treated, a stirrer that stirs the water to be treated, and an absorbance that measures the absorbance of the water to be treated. The absorbance acquisition unit that acquires the absorbance information indicating the absorbance of the water to be treated from the measurement unit, the absorbance information of the water to be treated before the aggregation treatment acquired by the absorbance acquisition unit, and the drug injection pump injects the drug. A control unit that controls a drug injection pump or a stirrer based on an index using the ratio of the absorbance information of the water to be treated during the agglomeration treatment obtained from the water tank in which the water to be treated that has been agitated by the stirrer is stored. , Equipped with.
Further, the coagulation treatment method according to the embodiment includes an absorbance acquisition step for acquiring absorbance information indicating the absorbance of the water to be treated from an absorbance measuring unit for measuring the absorbance of the water to be treated, and a pre-aggregation treatment method acquired in the absorbance acquisition step. The absorbance information of the water to be treated and the absorbance information of the water to be treated during the agglomeration treatment obtained from the water tank in which the drug is injected by the drug injection pump and the water to be treated is stored and stirred by the stirrer . It has a control step of injecting a drug for aggregating particles in the water to be treated by a drug injection pump into the water to be treated or controlling stirring of the water to be treated by a stirrer based on an index using a ratio.
Further, the coagulation treatment control device according to the embodiment has an absorbance acquisition unit that acquires absorbance information indicating the absorbance of the water to be treated from an absorbance measurement unit that measures the absorbance of the water to be treated, and an agglomeration treatment that is acquired by the absorbance acquisition unit. Absorbance information of the previous water to be treated and absorbance information of the water to be treated during the aggregation treatment obtained from the water tank in which the drug is injected by the drug injection pump and the water to be treated is stored which is agitated by the stirrer. A control unit for controlling a drug injection pump for injecting a drug for aggregating particles in the water to be treated into the water to be treated or a stirrer for stirring the water to be treated is provided based on an index using the ratio of.

The figure which shows the specific example of the coagulation sedimentation apparatus which realizes a general coagulation sedimentation process. The schematic diagram which shows the outline of the control of the coagulation sedimentation apparatus in 1st Embodiment. The figure which shows the specific example of the method of measuring the absorbance of the water to be treated flowing through a flow cell 210. The functional block diagram which shows the functional structure of the coagulation sedimentation control apparatus of 1st Embodiment. The figure which shows the specific example of the change of the absorbance of the water to be treated in the aggregation process. The schematic diagram which shows the outline of the control of the coagulation sedimentation apparatus in 2nd Embodiment. The figure which shows the specific example of the method of imaging the water to be treated flowing through a flow cell 210. The functional block diagram which shows the functional structure of the coagulation sedimentation control apparatus of 2nd Embodiment. The figure which shows the specific example of the image which the flock was imaged. The figure which shows the specific example of the image which the flock was imaged. The figure which shows the specific example of the image which the flock was imaged. The figure which shows the specific example of the image which the flock was imaged.

Hereinafter, the coagulation treatment system, the coagulation treatment method, the computer program, and the coagulation treatment control device of the embodiment will be described with reference to the drawings.

(Summary)
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 a coagulant. These flocculants (drugs) have the effect of aggregating unwanted substances in the water to be treated into flocs (aggregates) and forming larger flocs. Such agglomeration treatment is performed in various water treatment facilities. For example, in water purification plants, sand and clay soil components, plant debris, plankton such as algae, and macromolecular lysates that cause coloring are targeted for removal. Further, in the sewage treatment plant, a coagulation treatment is performed to improve the dehydration property of sludge. In addition, in factory wastewater treatment, a wide variety of unnecessary substances discharged from various factories are targeted for removal.

As described above, despite the wide variety of coagulation treatment targets, the current situation is that there are relatively few treatment method patterns. For example, in the coagulation treatment at a water purification plant, PAC (PAC (") is applied to the water to be treated.
Inorganic aluminum salts such as polyaluminum chloride) and sulfuric acid dust are injected as a flocculant, and flocs are formed by performing two-step stirring of rapid stirring and slow stirring. again,
The coagulation treatment in sewage treatment and factory wastewater treatment differs in that, in addition to the above-mentioned inorganic coagulant, a polymer coagulant in which a functional group having a positive or negative charge is introduced into an organic polymer such as polyacrylamide is used. The point that flocs are formed by stirring after injecting 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 of the drug according to the removal target
Control methods, methods for adjusting the functional group weight and molecular weight of drugs, etc. have become technologies and know-how in water treatment engineering. And, the evaluation of the state of the formed frock has been conventionally performed.
Evaluations have been made with an emphasis on the size of the frock. The reason why the size of the frock is used as an evaluation index is that the following Stokes' equation is used as a basic rule for the evaluation of the sedimentation property of the frock.

In the formula (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 gravitational acceleration, and η is the viscosity of the fluid. From the formula (1), it can be seen that the larger the particle size, the higher the settling speed and the higher the settling property. That is, it can be said that the purpose of the agglomeration treatment is to form larger flocs. Therefore, conventionally, the evaluation of the frock formation state has been made with an emphasis on the size of the frock. However, in this evaluation concept, no emphasis is placed on the specific density of particles. This is because substances to be removed generally have a relatively large specific density (about 1.4 to 2.7 in the case of mud and soil components), and large flocs are formed, which makes it easy to remove from the water to be treated. This is because it can be separated.

However, when targeting fine particles with poor sedimentation properties such as colloidal particles,
It may not be possible to form flocs with sufficient sedimentation by a general agglutination method. As a result, a large amount of chemicals are required to form the flocs, the formed flocs have poor sedimentation and take a long time to separate, the aggregation reaction itself takes a long time, and a large water tank is required to secure a long residence time. Problems such as increasing the size of equipment occur.

In order to solve such a problem, the aggregation control device of the embodiment controls the aggregation treatment based on the absorbance of the water to be treated or the shape of the flocs, in addition to the size of the flocs. 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 that realizes a general coagulation sedimentation process.
The coagulation sedimentation device 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 settling tank 180. The storage tank 110, the first coagulation tank 120, the second coagulation tank 160, and the settling tank 180 are installed adjacent to each other as shown in the figure, and a flow path for transporting the water to be treated is transported between the water tanks (not shown). ) Is provided. The water stored in the storage tank 110 can be used in the first coagulation tank 120, the second coagulation tank 160, and the settling tank 18 by using a height difference (hereinafter referred to as “head difference”), a pump, or the like.
It is transported in the order of 0.

The storage tank 110 is a water tank for storing the water to be treated. The first coagulation tank 120 is a water tank for pouring a chemical into the water to be treated and coagulating unnecessary substances. The drug storage tank 130 is a water tank for storing a drug 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 coagulation tank 120. In addition to these agents, the first coagulation tank 120 may be added with an acid such as hydrochloric acid or sulfuric acid or an alkali such as slaked lime or caustic soda as a pH adjusting agent for promoting the formation of flocs.

The stirrer 150 stirs the water to be treated flowing into the first coagulation tank 120. The stirrer 150
The water to be treated and the chemicals are uniformly mixed by rotating the stirring blade 152 by driving the motor 151. The stirring by the stirrer 150 is generally called a rapid stirring process, and has an effect of accelerating the diffusion of the flocculant and improving the collision probability between the drug and the suspended particulate solid. As a result, the sol component contained in the flocculant gels while binding to 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 coagulation tank 120 varies depending on the case, but it is generally taken for about 1 to 20 minutes, for example. The flocs formed in the first coagulation tank 120 have a size of about several tens of μm, and are very fine and have poor sedimentation properties.

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

The stirrer 170 stirs the water to be treated flowing into the second coagulation tank 160. The stirrer 170
The water to be treated is agitated by rotating the agitating blade 172 by driving the motor 171. The stirring by the stirrer 170 has an action of causing the flocs S1 to collide with each other. In general, the stirrer 170 stirs the water to be treated with a slower stirring strength than the stirrer 150. As a result, the fine flocs formed in the first coagulation tank 120 collide with or combine with the surrounding flocs in gentle stirring and gradually become large flocs. The residence time of the water to be treated in the second coagulation tank 160 varies depending on the case, but it is generally about 10 minutes to 1 hour. In addition, although the coagulation sedimentation device 100 is configured to perform mechanical agitation by the stirrer 170 in FIG. 1, it may be configured to perform agitation by a flow using a detour type flow path.

The settling tank 180 is a water tank for settling the flocs S2 formed in the second coagulation tank 160. In the settling tank 180, flocs are separated from the water to be treated by gravity settling due to the difference in specific gravity. In addition, in order to increase the separation speed, the settling tank 180 may be provided with an auxiliary means such as an inclined plate or a sludge blanket. The coagulation sedimentation device 100 is a settling tank 18.
By acquiring the supernatant liquid of the water to be treated in which the unnecessary substances have settled at 0, the water to be treated from which the unnecessary substances have been removed (hereinafter referred to as "treated water") is acquired.

FIG. 2 is a schematic diagram showing an outline of control of the coagulation sedimentation apparatus according to the first embodiment.
In FIG. 2, the broken line arrow indicates that a part of the water to be treated is separated from the coagulation sedimentation device 100. The preparative flow path 200 is a diagram schematically showing a flow path of the water to be treated separated from the coagulation sedimentation device 100. The flow cell 210 provided in the middle of the preparative flow path 200 is a pipeline for enabling the preparative water to be treated to be imaged. A part of the flow cell 210 is made of a transparent material such as glass so that the water to be treated flowing through the flow cell 210 can be imaged. The water to be treated flowing through the preparative flow path 200 flows into the flow cell 210 from the inflow port 211 and flows out to the preparative flow path 200 from the outflow port 212. The water to be treated is the first coagulation tank 120 and the second.
It may be separated from either the coagulation tank 160 or the settling tank 180, or from any part of each water tank. However, considering the time delay in control, it is desirable to inspect at the earliest possible time, so in this embodiment, it is assumed that the water to be treated is separated from the first coagulation tank 120.

The absorbance measuring 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 device 300 outputs the absorbance information indicating the measured absorbance to the coagulation sedimentation control device 1.

The coagulation sedimentation control device 1 acquires the absorbance information from the absorbance measuring device 300. The coagulation-sedimentation control device 1 acquires the flocculation state of the 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 treatment by the coagulation sedimentation device 100 based on the acquired coagulation 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 water to be treated flowing through the flow cell 210.
The circles in the flow cell 210 in FIG. 3 represent frocks in the water to be treated. The water to be treated separated from the coagulation sedimentation device 100 flows through the separation flow path and flows into the flow cell 210. The light source 310 irradiates the flow cell 210 with light having a specific wavelength. For example, the light source 310 may be
It is an LED (Light Emitting Diode). The absorbance measuring device 300 measures the absorbance of the water to be treated by measuring the light transmitted through the flow cell 210 among the light emitted 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, it may be configured to take out light having a specific wavelength by using a spectroscopic means such as a spectroscope or a bandpass filter. Further, when light having a plurality of wavelengths is used, the light source 310 may be used.
It may be configured to switch between a plurality of light sources that emit only light having a specific wavelength, may be configured to extract light having a plurality of wavelengths using the spectroscope, or may be configured to transmit light having different wavelengths. It may be configured to switch filters. Thus, the flow cell 210
The absorbance measuring device 300 and the light source 310 may have any configuration as long as the absorbance of the water to be treated can be measured.

FIG. 4 is a functional block diagram showing a functional configuration of the coagulation-sedimentation control device of the first embodiment.
The coagulation-sedimentation control device 1 includes a CPU (Central Processing Unit), a memory, an auxiliary storage device, and the like connected by a bus, and executes a control program. The coagulation-sedimentation control device 1 includes an absorbance acquisition unit 11, an coagulation state acquisition unit 12, and a control information generation unit 13 by executing a control program.
Functions as a device equipped with. All or part of each function of the coagulation sedimentation control device 1 is A.
SIC (Application Specific Integrated Circuit) and PLD (Programmable Logic Dev)
It may be realized by using hardware such as ice) 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 flexible disk, a magneto-optical disk, a portable medium such as a ROM or a CD-ROM, or a storage device such as a hard disk built in a computer system. The control program may be transmitted over a telecommunication line.

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

The aggregated state acquisition unit 12 is based on the absorbance information acquired by the absorbance acquisition unit 11.
Acquires the aggregated state of frock.

FIG. 5 is a diagram showing a specific example of the change in the absorbance of the water to be treated during the aggregation process.
FIG. 5 shows an absorption spectrum when a 100 μL / L aqueous solution of ink is aggregated in the neutral region using PAC. In FIG. 5, the horizontal axis represents the wavelength of the light irradiated to the water to be treated, and the vertical axis represents the absorbance measured for the light of each wavelength. Further, the plurality of series shown in FIG. 5 are
The legend on the right of the figure shows the relationship between wavelength and absorbance at each elapsed time. Here, the flocculant was injected at the start time of the coagulation process (0 min in the figure), and stirring was started at the same timing. In addition, the stirring here is 150 rpm (peripheral speed about 0) for the first 11 minutes.
.. Rapid stirring at 6 m / s) was followed by slow stirring at 50 rpm (peripheral speed of about 0.2 m / s).

Generally, unnecessary substances to be removed by coagulation sedimentation are particles having a diameter of about 0.01 μm to 100 μm. Particles larger than this can be separated by natural sedimentation without agglomeration. Particles with 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. Aqueous ink solution is an example of such a colloid, 1
It has a particle size of about 00 nm. Generally, for measuring the absorbance, 200 nm to 1000 n
Light having a wavelength of about m (ultraviolet to near infrared) is used. 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 size of the particles in the water to be treated.

In general, the effects of light wavelength and particle size on absorbance can be explained as follows.
First, if the particle size is large enough for the wavelength of light, the scattering of light can be geometrically approximated. In this case, there is almost no effect of the scattered light on the absorbance, and the absorbance has a high correlation with the concentration of the particles. Therefore, in such a case, the aggregated state can be determined by measuring the absorbance using light having a long wavelength such as red light.

Next, when the particle size is about the same as the wavelength of light, Mie scattering becomes dominant in the scattering of light. In this case, the absorbance has some correlation with the concentration of the particles, although the effect of the scattered light on the absorbance increases. Therefore, in such a case, the aggregated state can be determined by measuring the absorbance using light having a long wavelength such as red light, as in the case where the particle size is sufficiently large with respect to the wavelength of light.

Second, if the particle size is small enough for the wavelength of the light, the light scattering will include Rayleigh scattering. In this case, the influence of the scattered light on the absorbance becomes large, and the correlation between the absorbance and the concentration of the particles decreases. Therefore, in such a case, it is difficult to determine the aggregated state only by measuring the absorbance using light having a long wavelength such as red light.

The relationship between the wavelength and the particle size is clear 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 aggregated state is small. That is, this is
In the long wavelength region, it shows that the absorbance depends on the extinction coefficient and concentration of the particles. on the other hand,
In the short wavelength region, the change in absorbance is large with respect to the change in aggregated state. For example, it can be seen that there is no change in the absorbance for 3 minutes after the start of stirring, and that the absorbance decreases as the aggregation progresses after 5 minutes after the start of stirring. Then, it can be seen that the decrease in the absorbance almost converges in 11 minutes after the start, and the change in the absorbance is small in the 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 depending on the aggregated state. Particularly characteristic is that the absorbance decreases from 0.5 to 0.2 at a wavelength of 270 nm. Therefore, by measuring such a characteristic change in absorbance in advance as an index indicating the change in the aggregated state, the target aggregated state can be controlled by the absorbance.
For example, the index value using such absorbance is defined by the following equation (2).

In the formula (2), A0 represents the absorbance of raw water, 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 the ratio of the absorbance of the water to be treated during the agglutination treatment to the absorbance of the raw water, and is a value that decreases as the flocculation progresses. 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, the absorbance (that is, the absorbance of raw water) at time t = 0 [min] is A0, and time t = 11 [m].
The index value A calculated with the absorbance at [in] as A1 is calculated in advance.

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

The control information generation unit 13 generates control information for controlling the agglomeration and sedimentation apparatus 100 based on the agglomeration state information acquired by the agglomeration 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 the preset control target value and the current aggregation state. For example, in the coagulation sedimentation control device 1.
The appropriate drug injection amount according to the ratio between the control target value and the current aggregation state is stored in advance. In this case, the control information generation unit 13 generates control information for controlling the agglutination-precipitation control device 1 so that the drug injection amount or the stirring condition is set according to the ratio between the control target and the agglutination state. For example, the control information generation unit 13 determines that the flocculant is insufficient when the current index value is higher than the target index value, and generates control information for increasing the injection amount of the flocculant. In the opposite case,
It is determined that the flocculant is excessive, and control information for reducing the injection amount of the flocculant is generated. Further, the control information generation unit 13 replaces the injection amount of the coagulant with the stirring conditions (strength or time) of the stirrer.
You may generate control information to control.

When the absorbance is used to obtain the aggregated state as described above, for example, a phenomenon called drift may occur in which the measured value of the absorbance rises as a whole due to the adhesion of floc fragments to the flow cell. be. In such a case, in addition to the above-mentioned measured value of the wavelength of 270 nm, for example, if the measured value of the wavelength of 500 nm longer than 270 nm is acquired in advance, the following equations (3), (4) and (1) The effect of drift can be eliminated by normalization using the statistical values obtained in 5).

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

In this case, C0 (-1≤C0≤1) in the formula (3) becomes an index value indicating the amount of unnecessary substances contained in the raw water, and C1 decreases from the initial value C0 with the passage of the stirring time. go. That is,
C1 in the formula (4) is an index value of the aggregated state. Therefore, when C1 = C is obtained in advance as the control target value, the amount of the drug 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 the drug is insufficient or the stirring strength is insufficient, and the amount of the drug input is increased or the stirring strength is strengthened. Just do it. If the measured value C1 is smaller than the target value C, it may be determined that the amount of the drug is excessive or the stirring intensity is excessive, and the amount of the drug input may be reduced or the stirring intensity may be weakened. ..

The formula (5) is an example of a formula for determining the control value of the injection rate of the drug and the stirring intensity according to the change of the index value described above. In the equation (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 coagulation treatment system to be controlled.

In the case of a continuous system in which the water quality of the raw water changes continuously, the control target may be switched according to the change in the water quality of the raw water. Generally, in a water treatment system, the water quality of the water to be treated sent to the coagulation sedimentation device 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 the continuous system.

The coagulation-sedimentation control device 1 of the first embodiment configured in this way acquires the flocculation state of flocs based on the absorbance of the water to be treated. The absorbance of the water to be treated shows a remarkable change in light of a specific wavelength depending on the nature of the water to be treated. Therefore, based on the absorbance using light of such a specific wavelength, it is possible to evaluate the aggregated state more accurately even for an unnecessary substance having a small particle size such as colloidal particles. By performing such control based on the absorbance, the coagulation-sedimentation control device 1 can control the coagulation-sedimentation device 100 so that flocs having better sedimentation property are formed.

(Second embodiment)
FIG. 6 is a schematic diagram showing an outline of control of the coagulation sedimentation apparatus according to the second embodiment.
The coagulation-sedimentation control device 1 of the first embodiment determined the flocculation state based on the absorbance of the water to be treated. On the other hand, the coagulation-sedimentation control device 1a of the second embodiment determines the coagulation state of the flocs based on the image in which the water to be treated is captured.
The image pickup device 400 (imaging unit) acquires an image of the water to be treated separated from the coagulation sedimentation device 100 by taking an image of the flow cell 210. The image pickup apparatus 400 outputs the acquired image of the water to be treated to the coagulation sedimentation control apparatus 1.

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

FIG. 7 is a diagram showing a specific example of a method of imaging the water to be treated flowing through the flow cell 210.
The water to be treated separated from the coagulation sedimentation device 100 flows through the separation flow path and flows into the flow cell 210. The light source 310 irradiates the flow cell 210 with light. The image pickup device 400 is a light source 31.
By imaging the flow cell 210 illuminated by 0, an image of the separated water to be treated is acquired. The image pickup apparatus 400 outputs the acquired image of the water to be treated to the coagulation sedimentation control apparatus 1.

FIG. 8 is a functional block diagram showing a functional configuration of the coagulation sedimentation control device of the second embodiment.
The coagulation-precipitation control device 1a includes an image acquisition unit 14 instead of the absorbance acquisition unit 11, a point that the agglomeration state acquisition unit 12a is provided 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 device 1 of the first embodiment in that the unit 13a is provided.
The image acquisition unit 14 acquires an image of the water to be treated from the image pickup apparatus 400. The image acquisition unit 14 outputs the acquired image of the water to be treated to the aggregation state acquisition unit 12a.

The aggregated state acquisition unit 12a acquires the aggregated state of the frock based on the image of the water to be treated acquired by the image acquisition unit 14. Specifically, the aggregated state acquisition unit 12a identifies the contour of the frock from the image. The aggregated state acquisition unit 12a acquires a shape coefficient indicating the shape of the floc based on the contour of the identified floc. For example, the shape coefficient may be expressed by roundness, fractal order, or the like, or may be simply expressed by size (for example, area). The higher the roundness of the flocs, the better the sedimentation property, and the lower the fractal order, the better the sedimentation property. In addition, the larger the size, the better the sedimentation property. Any existing image recognition technique may be used as a method for identifying flocs from images. The agglomeration state acquisition unit 12a outputs the acquired frock shape coefficient to the control information generation unit 13a as agglomeration state information indicating the agglomeration state at that time.

In order to identify the outline of the frock from the image, the frock needs to be imaged so as to have an appropriate size in the image. Therefore, in the image pickup apparatus 400, it is necessary 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 photographing range may be set to about several hundred μm to several mm square, and a lens having a magnification of several times to several 100 times may be used. If it is difficult to obtain the contour of the frock, the frock can be imaged more clearly by using a phase-contrast microscope, coaxial epi-illumination, or the like, if necessary.

The control information generation unit 13a generates control information for controlling the agglomeration-separation apparatus 100 based on the agglomeration state information acquired by the agglomeration 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 the preset control target value and the current aggregation state. For example, if the flocs are not formed to a sufficient size, control information may be generated to increase the drug injection amount.
Further, if the flocs are not in a shape having a sufficiently good sedimentation property, control information that enhances the intensity 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 showing specific examples of images in which flocs are captured.
Each of FIGS. 9 to 12 is an image when a 100 μL / L ink solution of ink is aggregated in the neutral region using PAC. The plurality of images in each figure are images obtained by capturing a plurality of flocs formed in the same coagulation-precipitation treatment.

FIG. 9 shows a case where a flat blade stirrer is used for stirring, rapid stirring at 150 rpm (peripheral speed of about 0.6 m / s), and then slow stirring at 50 rpm (peripheral speed of about 0.2 m / s). It is an image of the captured flock. As is clear from the figure, the frock in this case is a distorted amorphous shape, and a relatively large frock is formed.

FIG. 10 shows rapid stirring at 1000 rpm (peripheral speed about 1.5 m / s) using a screw blade stirrer, and then slow stirring at 50 rpm (peripheral speed about 0.2 m / s) using a flat blade stirrer. It is an image of the flock taken when the above was performed. As is clear from the figure, the flocs have a distorted amorphous shape as in FIG. 9, and relatively large flocs are formed.

FIG. 11 shows rapid stirring at 3000 rpm (peripheral speed about 4.5 m / s) using a screw blade stirrer, and then slow stirring at 50 rpm (peripheral speed about 0.2 m / s) using a flat blade stirrer. It is an image of the flock taken when the above was performed. As is clear from the figure, the flock in this case has a rounded outline unlike the cases of FIGS. 9 and 10. Also, in this case, relatively small flocs are formed.

In FIG. 12, rapid stirring is performed at 6000 rpm (peripheral speed of about 9 m / s) using a screw blade stirrer, and then slow stirring is performed at 50 rpm (peripheral speed of about 0.2 m / s) using a flat blade stirrer. It is an image taken in the case of. As is clear from the figure, the shape of the frock in this case is closer to FIG. 11 than that of FIGS. 9 and 10, and the contour is rounded. Also, in this case, relatively large flocs are formed.

The sedimentation property of the frock obtained by such a coagulation sedimentation treatment is shown in FIGS. 12, 11, and 1.
It was good in the order of 0 and FIG. That is, it was obtained that the floc with better separability could be formed when the stirring strength of rapid stirring was increased.

In this way, the shape and size of the flocs greatly affect the sedimentation property of the flocs. Therefore, the aggregated state acquisition unit 12a acquires a shape coefficient indicating the shape and size of such a floc from an image in which the water to be treated is captured. The coagulation sedimentation control device 1a of the embodiment controls the stirring conditions of the coagulation sedimentation device 100 based on such a shape coefficient. With such control,
The coagulation sedimentation device 100 can form flocs with better sedimentation properties.

According to at least one embodiment described above, the injection amount of the drug to be injected into the water to be treated or the drug was injected based on the aggregated state of the flocs in the water to be treated obtained based on the image or the absorbance. By having a control unit that controls the stirring conditions of the water to be treated, it is possible to form flocs having better sedimentation properties.

Although some embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other embodiments, and various omissions, as long as they do not deviate from the gist of the invention,
Can be replaced or changed. These embodiments and variations thereof are included in the scope of the invention described in the claims and the equivalent scope thereof, as are included in the scope and gist of the invention.

1,1a ... Aggregation sedimentation control device, 11 ... Absorbance acquisition unit, 12,12a ... Aggregation state acquisition unit, 1
3,13a ... Control information generation unit, 14 ... Image acquisition unit, 100 ... Coagulation sedimentation device, 110 ... Storage tank, 120 ... First coagulation tank, 130 ... Drug storage tank, 140 ... Drug injection pump, 150 ... Stirrer, 151 ... Motor, 152 ... Stirring blade, 160 ... Second coagulation tank, 170 ... Stirrer, 171 ...
Motor, 172 ... stirring blade, 180 ... settling tank, 200 ... preparative flow path, 210 ... flow cell, 2
11 ... Inlet, 212 ... Outlet, 300 ... Absorbance measuring device, 310 ... Light source, 400 ... Imaging device

Claims (7)

A drug injection pump that injects a drug for aggregating particles in the water to be treated into the water to be treated,
A stirrer that stirs the water to be treated and
An absorbance acquisition unit that acquires absorbance information indicating the absorbance of the water to be treated from an absorbance measurement unit that measures the absorbance of the water to be treated, and an absorbance acquisition unit.
The absorbance information of the water to be treated before the agglomeration treatment acquired by the absorbance acquisition unit and the agglomeration acquired from the water tank in which the drug is injected by the drug injection pump and the treated water agitated by the stirrer is stored. A control unit that controls the drug injection pump or the stirrer based on an index using the ratio of the absorbance information of the water to be treated during the treatment.
A coagulation treatment system. A drug injection pump that injects a drug for aggregating particles in the water to be treated into the water to be treated,
A stirrer that stirs the water to be treated and
An absorbance acquisition unit that acquires absorbance information indicating the absorbance of the water to be treated from an absorbance measurement unit that measures the absorbance of the water to be treated, and an absorbance acquisition unit.
Of the absorbance information of the water to be treated during the aggregation treatment obtained from the water tank in which the drug is injected by the drug injection pump and the water to be treated is agitated by the stirrer, which is acquired by the absorbance acquisition unit. , A control unit that controls the drug injection pump or the stirrer, based on statistical values obtained from the respective absorbances at different wavelengths.
A coagulation treatment system. The absorbance acquisition step of acquiring the absorbance information indicating the absorbance of the water to be treated from the absorbance measuring unit for measuring the absorbance of the water to be treated, and
The absorbance information of the water to be treated before the agglomeration treatment acquired in the absorbance acquisition step and the agglomeration acquired from the water tank in which the drug is injected by the drug injection pump and the treated water agitated by the stirrer is stored. Controlling injection of a drug for aggregating particles in the water to be treated by a drug injection pump or stirring of the water to be treated by a stirrer based on an index using the ratio with the absorbance information of the water to be treated during the treatment. Control steps to do,
A coagulation treatment method having. The absorbance acquisition step of acquiring the absorbance information indicating the absorbance of the water to be treated from the absorbance measuring unit for measuring the absorbance of the water to be treated, and
Of the absorbance information of the water to be treated during the aggregation treatment acquired from the water tank in which the water to be treated is injected by the drug injection pump and agitated by the stirrer, which is acquired in the absorbance acquisition step. A control step for controlling the injection of a drug for aggregating particles in the water to be treated by a drug injection pump or the stirring of the water to be treated by a stirrer based on the statistical values obtained from the respective absorbances at different wavelengths. ,
A coagulation treatment method having. On the computer
A computer program for performing the various steps according to claim 3 or 4. An absorbance acquisition unit that acquires absorbance information indicating the absorbance of the water to be treated from an absorbance measurement unit that measures the absorbance of the water to be treated, and an absorbance acquisition unit.
Aggregation acquired from the water tank in which the absorption information of the water to be treated before the agglomeration treatment acquired by the absorbance acquisition unit and the water to be treated in which the drug is injected by the drug injection pump and agitated by the stirrer are stored. Based on the index using the ratio of the absorbance information of the water to be treated and the water to be treated, a drug injection pump for injecting a drug for aggregating particles in the water to be treated into the water to be treated or the water to be treated is used. A control unit that controls the stirrer to stir,
A coagulation processing control device. An absorbance acquisition unit that acquires absorbance information indicating the absorbance of the water to be treated from an absorbance measurement unit that measures the absorbance of the water to be treated, and an absorbance acquisition unit.
Of the absorbance information of the water to be treated during the aggregation treatment obtained from the water tank in which the water to be treated is injected by the medicine injection pump and agitated by the stirrer, which is acquired by the absorbance acquisition unit. Controls a drug injection pump that injects a drug for aggregating particles in the water to be treated into the water to be treated or a stirrer that stirs the water to be treated, based on statistical values obtained from the respective absorbances at different wavelengths. Control unit and
A coagulation processing control device.

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