JP4331421B2 - Aggregation state detector - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an agglomerated state detection device for detecting an agglomerated state of colloidal particles in water to be treated.
[0002]
[Prior art]
In order to purify treated water such as raw water from rivers into tap water, a coagulant is injected into the treated water, and colloidal particles such as suspended substances in the treated water are agglomerated to remove precipitates. It has been. In particular, colloidal particles having a diameter of 10 ⁻⁴ cm or less cannot be removed by ordinary precipitation treatment or filtration treatment, and must be removed by precipitation after agglomeration.
[0003]
Colloidal particles in natural water consist of clay-based turbidity having a main particle size distribution in the vicinity of 10 ⁻⁴ to 10 ⁻⁵ cm and fine organic organic coloring substances in the vicinity of 10 ⁻⁶ to 10 ⁻⁷ cm. Colloid is the main component, and artificial polluted rivers contain a large amount of organic substances of 10 ⁻⁶ cm or less. Since most of these colloidal particles are negatively charged, the water to be treated containing such colloidal particles forms a stable dispersion suspension system due to the repulsion between the negative charges between the colloidal particles. ing.
[0004]
The intensity of the surface charge of such colloidal particles is distributed in the range of about −20 to −30 mV in terms of zeta potential, which is the potential with respect to the solution bulk on the surface of the colloidal particles. This surface charge is neutralized by adding colloids or ions with opposite charges to the system, and as a result, if the zeta potential of the suspended particles is within the range of about ± 10 mV, the interparticle The van der Waals force exceeds the repulsive force of the surface charge and begins to agglomerate. The aggregating agent generates fine particles having the opposite charge to the colloidal particles that cause such an action in water. Generally, it is easily hydrolyzed in water to form a positively charged metal oxide colloid. The resulting metal salts such as aluminum and iron are used.
[0005]
The operation of injecting the flocculant into the water to be treated to agglomerate the colloidal particles in the water to be treated is performed first in a relatively short time in a rapid mixing basin with high agitation strength. To stir. Thereafter, the water to be treated is gently agitated to grow until the colloidal particles that have started agglomeration become larger agglomerates. Then, such agglomerates of colloidal particles are removed from the water to be treated by precipitation or filtration. The injected flocculant is sandwiched between negatively charged particles and attracts with positive and negative charges to strengthen the bond and as a binder to maintain the floc bond against the shear breaking force that increases with the floc growth. Shows the effect.
[0006]
Therefore, floc formation occurs when two conditions are satisfied: neutralization of the surface charge is below a predetermined value and a certain amount of hydrolyzed metal colloid acting as a binder. Will be done.
[0007]
By the way, the state of aggregation of the colloidal particles in the water to be treated is determined by measuring the light transmittance of the water to be treated containing colloidal particles, the flow potential of the water to be treated and the zeta potential, Determined based on differences. The streaming potential refers to a potential difference appearing between electrodes placed in the vicinity of both ends of the capillary when the water to be treated containing colloidal particles is moved in the capillary by a pressure difference.
[0008]
As a method for detecting the aggregation state of colloidal particles based on the light transmittance of the water to be treated, a method for detecting and analyzing the state of transmitted light by applying a light beam to the water to be treated is generally known.
[0009]
Thus, when detecting the aggregation state of colloidal particles based on the transmitted light of the water to be treated, the analysis of the aggregation state by the transmitted light is based on Gregory's theory (J. Gregory, J. of Colloid and Interface Science 105 357 (1985)). In the measurement method, a sample beam passing through a glass tube having an inner diameter of 1 mm is irradiated with a light beam of 0.1 mm width and 820 nm, and this transmitted light is detected by a photodiode. Since the probability of finding a particle in the sample water is proportional to the square root of the number of particles in the light beam, the mean square root of light transmission is proportional to the square root of the particle concentration. The theory (Y. Matsui et al., Wat. Sci. Tech., 27 153 (1993)), which is a further development of Gregory's theory, developed a light dispersion analysis method using two wavelengths. The soluble substance can be detected by 253 nm light, and the soluble substance can be detected by 253 nm light. The particle diameter of the colloidal particles can be determined from the average value of absorbance and the mean square root.
[0010]
On the other hand, in the detection method of the aggregation state of colloidal particles based on the measurement of the flow potential and zeta potential of the water to be treated, a method using a piston-type flow cell as an SCD (Streaming Current Detector) as a streaming potential measurement method (12th National ISA Analysis) Instruments Symposium, Houston, Tex. ., Wat. Res., 23 423 (1989)).
[0011]
[Problems to be solved by the invention]
As described above, the aggregation state of the colloidal particles in the water to be treated is determined based on the light transmittance of the water to be treated, the flow potential of the water to be treated, and the zeta potential.
[0012]
However, the following can be considered when the state of aggregation of the colloidal particles in the water to be treated is determined based on the light transmittance of the water to be treated.
[0013]
That is, when measuring the light transmittance of the water to be treated, a light receiving surface is required. However, when the light transmittance is measured, the light receiving surface is contaminated with the water to be treated, and the light transmission of the water to be treated is performed. It is conceivable that the rate cannot be measured accurately.
[0014]
Moreover, since the diameter of the aggregate of the colloidal particles made of suspended substances in the water to be treated varies invariably, the light scattering coefficient based on such colloidal particles also varies. The light transmittance of the water to be treated is greatly affected by the light scattering coefficient based on the colloidal particles. Therefore, the light transmittance of the water to be treated cannot be accurately measured depending on the state of the colloidal particles.
[0015]
On the other hand, when determining the aggregation state of the colloidal particles in the water to be treated based on the flow potential and zeta potential of the water to be treated, the following can be considered.
[0016]
That is, since the detected streaming potential and zeta potential change depending on the state of the cell wall contamination, it is considered that the streaming potential and zeta potential of the water to be treated cannot be accurately measured. In such a case, it is known that it is effective to use a diluted hydrogen peroxide solution of about 2 to 3% as a cleaning liquid in order to remove dirt on the cell wall surface. However, it is necessary to adjust the cleaning cycle and the cleaning time in accordance with the quality of each water, and the operation may be complicated.
[0017]
Further, when a piston type flow cell is used as the SCD, the cylinder wall surface may be deteriorated by the reciprocating motion of the piston, and the distance between the cylinder and the wall surface may fluctuate. In addition, the piston motion itself may be modulated by mechanical degradation.
[0018]
The present invention has been made in consideration of such points, and an object thereof is to provide an aggregation state detection device that can easily detect the aggregation state of colloidal particles in water to be treated by a simple method. .
[0019]
[Means for Solving the Problems]
The present invention relates to an agglomerated state detection apparatus for detecting the agglomerated state of colloidal particles in the water to be treated. A pair of electrodes arranged at a certain distance in the straight pipe, a potentiometer connected to the pair of electrodes and measuring a potential difference generated in the water to be treated between the pair of electrodes, and disposed in the vicinity of the pair of electrodes A pair of auxiliary electrodes connected to the potentiometer , and the potentiometer measures the potential difference of the water to be treated measured based on the pair of electrodes based on the pair of auxiliary electrodes. The aggregation state detecting device is characterized in that the aggregation state of colloidal particles in the water to be treated is detected based on the corrected potential difference .
[0020]
According to the present invention, the state of aggregation of colloidal particles in the water to be treated can be detected based on the flow potential of the water to be treated measured by the potentiometer. Therefore, the aggregation state of the colloidal particles in the water to be treated can be detected very simply and simply.
[0021]
Preferably, the insulating straight pipe is mainly made of acrylic resin or vinyl chloride resin.
[0022]
Preferably, the inner diameter of the insulating straight pipe is 10 mm or less.
[0023]
Preferably, the pair of electrodes is mainly composed of Ag, Au, or Pt.
[0024]
Preferably, the potentiometer is an electrometer for detecting a streaming potential, and the electrometer has an input resistance of 10 ⁶ ohms or more.
[0025]
Preferably, a transport tube is detachably attached to at least one of the inlet and the outlet of the insulating straight pipe via a hose nipple.
[0026]
Preferably, the apparatus further includes a tube pump capable of feeding the water to be treated at a constant speed, and the water to be treated is 1 liter / min or more and 20 liter / min or less in the insulating straight pipe by the tube pump. Washed away.
[0027]
Preferably, a pair of auxiliary electrodes connected to a potentiometer is disposed in the vicinity of the pair of electrodes, and the potentiometer measures the potential difference of the water to be treated measured based on the pair of electrodes. Correction is made by the potential difference measured based on the electrodes.
[0028]
Preferably, the apparatus further includes a flocculant injection control device that is connected to the potentiometer and controls the injection amount of the flocculant injected into the water to be treated. The flocculant injection control device includes the water to be treated from the potentiometer. Based on the potential difference, the amount of the flocculant injected into the water to be treated is controlled.
[0029]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
[0030]
1 to 3 are views showing an embodiment of the present invention. Here, FIG. 1 is a block diagram showing an agglomerated state detection device for detecting the agglomerated state of colloidal particles in the water to be treated. FIG. 2 is a diagram showing the relationship between the flow potential of the water to be treated detected by the coagulation state detection device and the measurement time, and FIG. 3 shows the floc particle diameter in the water to be treated and the flocculant (polyaluminum chloride). It is a figure which shows the relationship with injection amount.
[0031]
As shown in FIG. 1, an agglomeration state detection apparatus 1 according to the present invention includes an insulating straight pipe 2 through which water to be treated containing colloidal particles flows at a constant speed, and an insulating straight pipe 2 attached to the insulating straight pipe 2. 2 and a pair of electrodes 11 arranged at a fixed distance so as to protrude into the area 2.
[0032]
The insulating straight pipe 2 is mainly made of acrylic resin, and the inner diameter of the insulating straight pipe 2 is set to 10 mm or less. It has been confirmed by experiments that the flow potential of the water to be treated flowing in the insulating straight pipe 2 can be sufficiently detected if the insulating straight pipe 2 is a capillary having an inner diameter of 10 mm or less. It is based on being. Therefore, an appropriate value of 10 mm or less can be selected for the inner diameter of the insulating straight pipe 2.
[0033]
Such an insulating straight pipe 2 is supported by a straight pipe sensor support 13. The pair of electrodes 11 is mainly made of Ag.
[0034]
The pair of electrodes 11 is connected to an electrometer 3 (potential difference measuring meter) for detecting a streaming potential via a first conductive wire 11 a, and the electrometer 3 has a potential difference (streaming potential) generated in water to be treated between the pair of electrodes 11. ). A recorder 4 is attached to the electrometer 3, and the recorder 4 records the relationship between the flow potential of the water to be treated and the measurement time with a pen recorder based on the signal sent from the electrometer 3. It is supposed to be. The electrometer 3 has an input resistance of 10 ⁶ ohms or more.
[0035]
In addition, a pair of auxiliary electrodes 12 made of Ag are disposed in the vicinity of the pair of electrodes 11, and the pair of auxiliary electrodes 12 are connected to the electrometer 3 through the second conductive wire 12a. The electrometer 3 corrects the potential difference of the water to be treated measured based on the pair of electrodes 11 by the potential difference of the water to be treated measured based on the pair of auxiliary electrodes 12, thereby obtaining the flow potential of the water to be treated. It comes to decide.
[0036]
A transport tube 14 is detachably attached to an inlet and an outlet of the insulating straight pipe 2 via a hose nipple 15, and the transport tube 14 attached to each of the inlet and the outlet of the insulating straight pipe 2 stores water. It is connected to the tank 5.
[0037]
A tube pump 6 is attached to the transfer tube 14 between the inlet of the insulating straight pipe 2 and the water storage tank 5. The water to be treated is sent from the water storage tank 5 through the transfer tube 14 to the insulating straight pipe 2 by the tube pump 6 at a constant speed, and flows through the insulating straight pipe 2 at a constant speed. The tube pump 6 is set so as to send the water to be treated from the water storage tank 5 to the insulating straight pipe 2 at a speed of 1 liter per minute (L).
[0038]
A flow meter for measuring the flow rate of water to be treated sent from the water storage tank 5 to the insulating straight pipe 2 through the conveying tube 14 is provided in the transfer tube 14 between the inlet of the insulating straight pipe 2 and the tube pump 6. 7 is attached.
[0039]
The water storage tank 5 includes a flocculant tank 8 filled with a flocculant, and a flocculant addition valve 9 that adjusts the amount of flocculant added from the flocculant tank 8 to the water to be treated in the water storage tank 5. , Is provided. Note that polyaluminum chloride (PAC) 16 is used as the flocculant. Further, by adjusting the flocculant addition valve 9, 0.5 to 10 mg / L of polyaluminum chloride 16 can be appropriately added to the water to be treated in the water storage tank 5.
[0040]
A coagulant injection control device 10 is connected to the electrometer 3. The flocculant injection control device 10 adjusts the flocculant addition valve 9 based on the flow potential of the water to be treated from the electrometer 3, and the injection amount of the polyaluminum chloride 16 injected from the flocculant tank 8 into the water storage tank 5. Is to control.
[0041]
In the water tank 5, a solution obtained by dissolving 50 mg / L of kaolin as colloidal particles in tap water, performing rapid stirring at 150 rpm for 5 minutes, and slow stirring at 50 rpm for 15 minutes is used.
[0042]
Next, the operation of the present embodiment having such a configuration will be described.
[0043]
First, an outline of measurement of the aggregation state of colloidal particles in the water to be treated will be described.
[0044]
First, the water to be treated in the water storage tank 5 is sent from the water storage tank 5 to the insulating straight pipe 2 via the transfer tube 14 by the tube pump 6. The flow rate of the water to be treated flowing through the transfer tube 14 is measured by the flow meter 7.
[0045]
The water to be treated sent to the insulating straight pipe 2 by the tube pump 6 flows through the insulating straight pipe 2 at a rate of 1 liter per minute and is insulated from the inlet of the insulating straight pipe 2 through the pair of electrodes 11. It flows to the outlet of the straight pipe 2.
[0046]
The flow rate of the water to be treated flowing in the insulating straight pipe 2 is not limited to the above, and the flow potential of the water to be treated is detected in consideration of the relationship with the inner diameter of the insulating straight pipe 2. A flow rate that can be selected can be selected. According to experiments, when the inner diameter of the insulating straight pipe 2 is 10 mm, the flow potential of the water to be treated can be detected if the flow rate of the water to be treated is 1 liter per minute. If the flow rate of the water to be treated is 20 liters or more per minute, the flow of the water to be treated in the insulating straight pipe 2 becomes unstable, the flow potential vibrates, and the absolute value of the flow potential itself increases. Therefore, when the insulating straight pipe 2 having an inner diameter of 10 mm or less is used, the tube pump allows the water to be treated to flow through the insulating straight pipe at a constant rate of 1 liter / min or more and 20 liter / min or less. It is preferable to set as follows.
[0047]
During this time, the potential difference of the water to be treated between the pair of electrodes 11 is detected by the electrometer 3 from the pair of electrodes 11 through the first conductive wire 11a. At the same time, the potential difference of the water to be treated between the pair of auxiliary electrodes 12 arranged in the vicinity of the pair of electrodes 11 is detected by the electrometer 3 from the pair of auxiliary electrodes 12 through the second conductive line 12a.
[0048]
The electrometer 3 corrects the detected potential difference of the water to be treated between the pair of electrodes 11 by the potential difference of the water to be treated between the pair of auxiliary electrodes 12 to determine the flow potential of the water to be treated. The flow potential of the water to be treated determined in this way is sent from the electrometer 3 to the recorder 4.
[0049]
As shown in FIG. 2, the recorder 4 records the relationship between the flow potential of the water to be treated sent from the electrometer 3 and the measurement time using a pen recorder. In addition, the A area | region of FIG. 2 shows the case where the polyaluminum chloride 16 is not added to the to-be-processed water in the water storage tank 5, and the flow potential of to-be-processed water is vibrating around 150mV. 2 shows a case where 3 mg / L of polyaluminum chloride 16 is added to the water to be treated in the water tank 5, and the flow potential of the water to be treated vibrates around 130 mV. The flow potential of the water to be treated was 15 to 20 mV when the insulating straight pipe 2 was filled with the water to be treated and the water to be treated was stopped.
[0050]
The water to be treated that flows through the insulating straight pipe 2 and reaches the outlet of the insulating straight pipe 2 is returned to the water storage tank 5 through the transfer tube 14.
[0051]
As described above, the flow potential of the water to be treated in the water storage tank 5 is detected as shown in FIG. 2, and the aggregation state of the colloidal particles is detected.
[0052]
Comparing the A region and the B region in FIG. 2, it is considered that the flow potential of the water to be treated is reduced by adding the polyaluminum chloride 16 as a flocculant to the water to be treated in the water storage tank 5.
[0053]
On the other hand, when the relationship between the flocculant injection rate into the water to be treated and the particle size of floc formed in the water to be treated was examined, the results shown in FIG. 3 were obtained from the experiment. FIG. 3 shows the polyaluminum chloride injected into the water to be treated when polyaluminum chloride 16 is added to the water to be treated in which 50 mg / L of kaolin is dissolved in tap water and the number of stirring is 120 rpm at 25 ° C. The relationship between the density | concentration of the aluminum of 16 and the particle diameter of the floc formed in to-be-processed water is shown. FIG. 3 shows that the particle size of floc in the water to be treated increases as the flocculant injection rate increases. In addition, when polyaluminum chloride 16 is added to water to be treated in which 50 mg / L of kaolin is dissolved in tap water, rapid stirring is performed at 25 ° C. for 5 minutes at 150 rpm, and slow stirring is performed for 15 minutes at 50 rpm. The same result was obtained.
[0054]
2 and 3 that the flow potential of the water to be treated decreases as the particle size of the floc in the water to be treated increases. From this, the flow potential of the water to be treated decreases as the aggregation of the colloidal particles in the water to be treated progresses, so the state of colloidal particles in the water to be treated is detected from the detected flow potential of the water to be treated. be able to.
[0055]
Further, according to Kita (basic electrochemical, Gihodo 1980 P-147), streaming potential E _s is given by the following equation.
[0056]
E _s = I _s · R = −ε ₀ εΔPζ / kη
(Ε ₀ : dielectric constant in vacuum, ε: solution dielectric constant, ΔP: pressure difference, ζ: zeta potential, k: specific electrical conductivity of solution, η: viscosity coefficient of solution)
Therefore, the streaming potential is proportional to the zeta potential (ζ). The zeta potential is a potential with respect to the solution bulk of the solution slip surface on the surface of the colloidal particles, and is almost zero because the colloidal particles are agglomerated and become equal to the potential of the solution bulk in an unstable state. This also shows that the value of the streaming potential decreases as the aggregation of colloidal particles proceeds and approaches zero.
[0057]
As explained above, the state of aggregation of the colloidal particles in the water to be treated is detected from the flow potential of the water to be treated detected by the aggregation state detection device 1 according to the present invention, and the flow potential of the water to be treated decreases. It can be seen that the aggregation of colloidal particles in the water to be treated is progressing. Therefore, according to the aggregation state detection apparatus 1 according to the present invention, the aggregation state of the colloidal particles in the water to be treated can be easily detected by a simple method.
[0058]
Moreover, since the aggregation state detection apparatus 1 has a very simple structure and is configured at a low cost, there is no phenomenon that the driving unit is complicated and thus deteriorates, and when measuring the light transmittance of water to be treated. It is not necessary to consider the problem of contamination on the light receiving surface. Therefore, the aggregation state detection apparatus 1 according to the present invention can be stably operated continuously.
[0059]
Further, the insulating straight pipe 2 in the present embodiment is made of acrylic resin. Since the acrylic resin is easily available and excellent in workability, a high-quality insulating straight pipe 2 can be obtained. Further, since the acrylic resin is transparent, the state of dirt in the insulating straight pipe 2 can be easily known.
[0060]
The material of the insulating straight pipe 2 is not limited to acrylic resin. For example, even when the insulating straight pipe 2 made of vinyl chloride resin, which is easily available and excellent in workability, is used, it is in an aggregated state. It has been confirmed by experiments that it functions as the detection device 1.
[0061]
The pair of electrodes 11 is mainly made of Ag. In general, Ag is excellent in the stability of the electrode potential in an aqueous solution. Therefore, the flow potential of the water to be treated based on the pair of electrodes 11 can be obtained accurately and stably.
[0062]
Note that the material of the pair of electrodes 11 is not limited to Ag, and Au and Pt are excellent in the stability of the electrode potential in an aqueous solution, and thus can be used as the material of the pair of electrodes 11. However, when Ag is used as the material of the pair of electrodes 11, the overvoltage is lowest as compared with the case of using Au or Pt. Therefore, Ag is superior as the material of the pair of electrodes 11.
[0063]
The pair of auxiliary electrodes 12 are also made of Ag. For this reason, the pair of auxiliary electrodes 12 is excellent in the stability of the electrode potential in the aqueous solution. Therefore, the potential difference of the water to be treated based on the pair of auxiliary electrodes 12 can be obtained accurately and stably. As a material of the pair of auxiliary electrodes 12, AgCl that is excellent in stability of electrode potential in an aqueous solution may be used.
[0064]
Moreover, since the conveyance tube 14 is detachably connected to the inlet and outlet of the insulating straight pipe 2 via the hose nipple 15, the conveyance tube 14 can be freely detached from the hose nipple 15, and the insulating straight pipe By separating 2 and the transport tube 14, the inside of the insulating straight pipe 2 can be easily cleaned.
[0065]
Further, since the water to be treated is caused to flow through the insulating straight pipe 2 at a constant speed by the tube pump 6, the electrometer 3 can accurately obtain the flow potential of the water to be treated.
[0066]
The electrometer 3 has an input resistance of 10 ⁶ ohms or more. Therefore, the electrometer 3 has an input resistance sufficient to detect the flow potential of the water to be treated based on a minute current.
[0067]
Further, the amount of the flocculant injected into the water to be treated is controlled by the flocculant injection control device 10 appropriately opening and closing the flocculant addition valve 9 based on the flow potential of the water to be treated from the electrometer 3. Accordingly, an appropriate amount of the flocculant is automatically injected into the water to be treated according to the state of the colloidal particles in the water to be treated.
[0068]
【The invention's effect】
As described above, according to the aggregation state detection apparatus of the present invention, the aggregation state of the colloidal particles in the water to be treated is determined based on the flow potential of the water to be treated flowing in the insulating straight pipe measured by the potentiometer. Can be detected. Therefore, the aggregation state of the colloidal particles in the water to be treated can be detected very simply and simply, and the aggregation state detection device can be configured at low cost.
[Brief description of the drawings]
FIG. 1 is a configuration diagram illustrating an aggregation state detection device according to the present invention.
FIG. 2 is a diagram showing the relationship between the flow potential of the water to be treated detected by the aggregation state detection device and the measurement time.
FIG. 3 is a diagram showing the relationship between the floc particle diameter in the water to be treated and the amount of flocculant injected.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Aggregation state detection apparatus 2 Insulating straight pipe 3 Electrometer 4 Recorder 5 Water storage tank 6 Tube pump 7 Flowmeter 8 Coagulant tank 9 Coagulant addition valve 10 Coagulant injection control apparatus 11 Pair of electrodes 11a First conductive wire 12 A pair of auxiliary electrodes 12a Second conductive wire 13 Straight pipe sensor support 14 Transport tube 15 Hose nipple 16 Polyaluminum chloride

Claims (8)

In the aggregation state detection device for detecting the aggregation state of the colloidal particles in the water to be treated,
An insulating straight pipe through which water to be treated containing colloidal particles flows at a constant speed;
A pair of electrodes attached to the insulating straight pipe and arranged at a certain distance in the insulating straight pipe;
A potentiometer connected to the pair of electrodes and measuring a potential difference generated in the water to be treated between the pair of electrodes;
A pair of auxiliary electrodes disposed in the vicinity of the pair of electrodes and connected to a potentiometer,
The potentiometer corrects the potential difference of the water to be treated measured based on the pair of electrodes by the potential difference measured based on the pair of auxiliary electrodes, and colloidal particles in the water to be treated based on the corrected potential difference. An agglomerated state detection device characterized in that an agglomerated state of is detected.   The aggregation state detection device according to claim 1, wherein the insulating straight pipe is mainly made of an acrylic resin or a vinyl chloride resin.   The aggregation state detection device according to claim 1, wherein an inner diameter of the insulating straight pipe is 10 mm or less.   4. The aggregation state detection device according to claim 1, wherein the pair of electrodes is mainly made of Ag, Au, or Pt. 5. The potentiometer is an electrometer for detecting streaming potential,
5. The aggregation state detection device according to claim 1, wherein the electrometer has an input resistance of 10 ⁶ ohms or more.   The conveying tube is detachably attached to at least one of the inlet and the outlet of the insulating straight pipe via a hose nipple. Aggregation state detection device. It further includes a tube pump that can feed the water to be treated at a constant speed,
The treated water is flowed at a constant speed of 1 liter / min or more and 20 liter / min or less in an insulating straight pipe by a tube pump. Aggregation state detection device. A flocculant injection control device that is connected to the potentiometer and controls the injection amount of the flocculant injected into the water to be treated;
The flocculant injection control device controls the injection amount of the flocculant into the water to be treated based on the potential difference of the water to be treated from the potentiometer. The agglomeration state detection apparatus described in 1.

Images