JP2011194356A - Apparatus for treatment of wastewater containing cpc - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an apparatus for treatment of wastewater containing CPC which easily separates and recovers CPC in a wastewater containing CPC, inhibits consumption of unnecessary energy and increases contribution to a low carbon society.SOLUTION: A halide salt is added to the wastewater containing CPC and reaction matter of the CPC and the halide salt is produced and separated.

Description

  The present invention relates to a CPC-containing wastewater treatment apparatus having a coagulation separation function for treating CPC-containing wastewater generated in a hyaluronic acid production process and recovering CPC.

The field of use of CPC, its properties, and the effects on water treatment are described below.
・ Cetylpyridinium Chloride (CPC) is a kind of synthetic “cationic lipid” discovered in the 1930s. It is a “lipid” and is also a typical cationic surfactant.
-As another feature, strong sterilization and fungicidal action has been recognized, so it is industrially used in the medical and cosmetic fields, and as an example it is used for tissue paper and throat candy. Next, in terms of properties such as surfactants, they are widely used in general industrial fields such as separation and purification of acidic polysaccharides and charge control agents for toners.
Chemical formula of CPC is _{C 21 H 38 CIN · H 2} O (MW358.01), monohydrate, there is a anhydrides.
-Since CPC shows a strong bactericidal action, a problem arises when biological treatment is used to treat CPC. As an example of the sterilizing effect of CPC, brewer's yeast known for industrial use is sterilized by 99.9% or more within 5 minutes at 10 ppm of CPC.
As an example of CPC use in the cosmetics field, it is used for fixing hyaluronic acid during the production of hyaluronic acid. CPC is mixed with the wastewater from the hyaluronic acid production process and discharged. When this wastewater (factory wastewater) is treated, the activated sludge is activated by the sterilization action of CPC in the biological treatment equipment normally used in the wastewater treatment process. Is impeded, and the capacity of biological treatment is reduced, impeding wastewater treatment.

Next, a conventional CPC processing method will be described.
-Since removal of CPC, that is, disposal of wastewater from the manufacturing process is carried out at the production process site of the manufacturing company, the content of “production to wastewater treatment” is usually a trade secret (undisclosed).
・ Even when the industrial waste disposal contractor is requested to dispose of CPC-containing wastewater, the wastewater composition is a trade secret.
・ As for the treatment and disposal methods of CPC-containing wastewater known so far, it is first carried out as industrial waste liquid without treatment as described above, or diluted and discharged to be below the water quality standard, or expensive. There was a method of processing with an ion exchange apparatus or the like at an expense (CPC adsorption removal) or cooling the CPC-containing wastewater itself.
-In the dilution treatment, when biological treatment is performed without releasing, it is necessary to dilute to an activity inhibitory concentration or less.
-In the ion exchange treatment, since CPC is a cationic surfactant, it is adsorbed and removed by an anion exchange resin.
-Since the cooling treatment precipitates and crystallizes when the temperature is lowered due to the characteristics of CPC, the CPC-containing wastewater itself is cooled to around zero degrees and separated and removed.

Japanese Patent Publication No. 5-77681 JP 2006-265287 A

Conventionally, problems and problems when CPC is not removed will be described below.
・ If CPC is not removed from wastewater, it will reduce the ability of biological treatment in the wastewater treatment process, and if CPC is not removed sufficiently and released into the natural world (public water area), it will be ecological due to its strong sterilizing effect. It also has an adverse effect on the system.
-The CPC concentration of waste water varies depending on the production process, but there is an example of 0.1% to several percent. When processing and disposing of such CPC-concentrated wastewater, there are the following problems.
(1) If you entrust the CPC-containing wastewater in industrial waste disposal unloading disposal, it takes about 7,000～10,000 yen / m ^3, is very costly. In addition, drainage storage facilities and unloading facilities are required, leading to an increase in facility costs, and complicated unloading operations and facility maintenance operations.
(2) When the dilution method is used for CPC removal, the CPC concentration needs to be 10 to 20 mg / L in order to eliminate the inhibition in biological treatment. In this case, the dilution rate must be 50 times or more even when the CPC concentration of the wastewater is 0.1%, and not only a large amount of diluted water is required but also a large amount of diluted wastewater must be biologically treated. In addition, the cost of dilution water and biological treatment costs are increased, and accurate operation management and maintenance according to the drainage properties are required.
(3) When the ion exchange method is applied to CPC removal, it is difficult to reduce the CPC concentration of treated water to 0.1% (1000 mg / L) or less, and it can be used for wastewater containing high CPC concentration, but low-concentration wastewater treatment. Is difficult. Furthermore, it is necessary to provide a separate ion exchange facility for the wastewater treatment process, the ion exchange resin is expensive, the resin regeneration work is complicated, and the equipment cost and the operation cost are increased.
(4) When the cooling method is applied to CPC removal, it is necessary to cool the CPC-containing wastewater itself to around zero degrees, which increases the equipment cost and operation cost. Consumption significantly increases and goes against energy saving and carbon dioxide reduction. Furthermore, it is difficult to deposit in wastewater with a low CPC concentration.
(5) As described above, it is necessary to reliably remove CPC from the wastewater, but the conventional removal method is not only very expensive, but also has concentration restrictions, especially from low-concentration CPC wastewater. There is an urgent need for a technique for removing CPC stably and stably.

  The present invention has been made to solve the above-described problems, and can easily separate and recover CPC in CPC-containing wastewater, avoid unnecessary energy consumption, and contribute to a low-carbon society. An object of the present invention is to provide a CPC-containing wastewater treatment apparatus whose contribution is increased.

  The CPC-containing wastewater treatment apparatus according to the present invention is characterized in that a halogenated salt is added to CPC-containing wastewater, and a reaction product of CPC and the halogenated salt is generated and separated.

  The CPC-containing wastewater treatment apparatus according to the present invention includes a reaction vessel that introduces and stirs CPC-containing wastewater, a chemical addition facility that adds a halogenated salt to the CPC-containing wastewater, and CPC and halogenation from a mixture of the reaction vessel. It is characterized by comprising a solid-liquid separation tank for separating a reaction product with a salt.

  The reaction tank of the CPC-containing wastewater treatment apparatus according to the present invention includes a rapid stirring tank.

  The halogenated salt applied to the CPC-containing wastewater treatment apparatus according to the present invention is potassium iodide or potassium bromide.

  In the present invention, CPC is removed by adding a halide salt such as potassium iodide (KI) to CPC-containing wastewater to produce a reaction product (solid) and separating it. This invention has been made by the inventors of the present invention as a result of earnest test research. In the treatment test for CPC-containing wastewater, potassium iodide is added to the CPC-containing wastewater and left to stand to produce transparent crystals. This is the first demonstration. The formation of this CPI crystal is thought to be due to the reaction shown in the following chemical formula.

〔Chemical formula〕
C ₂₁ H ₃₈ N ⁺ (aq) + I ⁻ (aq) → C ₂₁ H ₃₈ NI (S) Formula 1

(aq): Dissolved in aqueous solution (S): Solid

When KI is added to the CPC solution, it is changed to CPI due to the oxidizing power of iodine and solidifies.
Usually, when present in water with iodine liberated, the aqueous solution is colored, but in this reaction it is transparent and not colored. From this, the above reaction was considered.
It was also found that potassium bromide (KBr) is also effective as a halide salt.

Based on the demonstration of the above reaction, agglomeration separation, which was conventionally possible at a high concentration of several percent in the solution and was possible for the first time under the condition that the agglomeration temperature is 0 ° C. or less, was 1,000 mg / L at a liquid temperature of about 10 to 30 ° C. Even in a solution containing about (0.1%) CPC.
Therefore, the present invention has the following effects.
・ Eliminates the need to dilute with a huge amount of water to reduce the impact on the existing activated sludge wastewater treatment facility at the production plant, thereby reducing the dilution water and increasing the treatment capacity of the wastewater treatment facility due to the increase in the amount of wastewater treatment due to dilution. Can be avoided.
・ The construction and maintenance of facilities such as the ion exchange method and cooling method require enormous costs, and facilities that are complicated to operate and difficult to manage can be eliminated.
-The above two typical effects can avoid unnecessary energy consumption and increase the contribution to a low-carbon society.

Embodiment 1 FIG.
FIG. 1 is a flowchart showing a basic CPC-containing wastewater treatment apparatus according to Embodiment 1 of the present invention. The CPC-containing wastewater treatment apparatus according to Embodiment 1 includes a reaction tank 1 for introducing CPC-containing wastewater from a raw water inflow pipe 2, a chemical supply facility 3 for adding a halide salt to CPC-containing wastewater, and the reaction tank 1 And a stirrer 4 that stirs and mixes the CPC-containing wastewater and the halide salt, and a mixture of the CPC-containing wastewater and the halide salt is introduced from the reaction tank 1 to separate the reaction product of CPC and the halide salt. The basic structure includes a liquid separation facility 6.

  In Embodiment 1, the halogenated salt from the chemical supply facility 3 is added to the CPC-containing wastewater in the raw water inflow pipe 2, but even if the halogenated salt is added directly to the CPC-containing wastewater in the reaction tank 1. good.

  Halogenated salt added to the CPC-containing wastewater from the chemical supply equipment 3 is KI, KBr, etc., but the type is not limited, and a mixture of different types of halogenated salts may be used. Liquid halide salts may also be used.

Although the said chemical | medical agent supply equipment 3 is comprised by the chemical | medical agent storage tank and the chemical | medical agent supply pump, the structure is not ask | required.
Further, when a precipitation tank is used as the solid-liquid separation facility 6, the precipitation tank may be a normal one, and the shape thereof is not limited to a circle or a rectangle.

  In FIG. 1, 5 is a convection pipe for transferring the mixed liquid in the reaction tank 1 to the solid-liquid separation equipment 6, 7 is a treated water discharge pipe for discharging the separation treated water of the solid-liquid separation equipment 6, and 8 is solid-liquid separation. This is a reactant drawing tube for discharging a reaction product (solid matter) that has been separated into solid and liquid by the equipment 6 and precipitated.

Next, the operation will be described.
CPC-containing wastewater (raw water) that is raw water flowing through the raw water inflow pipe 2 is introduced into the reaction tank 1 as a mixed liquid with a halide salt such as potassium iodide (KI) added from the chemical supply facility 3. The The mixed solution introduced into the reaction tank 1 is stirred and mixed by the stirrer 4 to generate a solidified reaction product, and the mixed solution containing the reaction product is separated into solid and liquid via the transfer pipe 5. In the solid-liquid separation facility 6, the CPC contained in the mixed liquid is precipitated as a reaction product (solid matter) and discharged from the reactant drawing tube 8 connected to the lower part of the solid-liquid separation facility 6. The supernatant liquid of the solid-liquid separation facility 6 is discharged out of the system from the treated water discharge pipe 7 as treated water.

In Embodiment 1 demonstrated above, by adding halogenated salts, such as potassium iodide, to CPC containing waste_water | drain, it produces | generates and isolate | separates CPC contained in the liquid mixture as a solidified (aggregated) reactant. it can. This has been achieved by the inventors of the present invention after intensive research, and in the treatment test for CPC-containing wastewater, potassium iodide is added to the CPC-containing wastewater and left to stand to produce transparent crystals. This was demonstrated for the first time, and the formation of the CPI crystal is thought to be due to the following reaction.

C ₂₁ H ₃₈ N ⁺ (aq) + I ⁻ (aq) → C ₂₁ H ₃₈ NI (S) Formula 1

(aq): Dissolved in aqueous solution (S): Solid

When KI is added to the CPC solution, it is changed to CPI due to the oxidizing power of iodine and solidifies.
Usually, when present in water in a state where iodine is liberated, the aqueous solution is colored, but in this reaction, it is transparent and not colored. From this, the above reaction was considered.
It was also found that potassium bromide (KBr) is also effective as a halide salt.

As a result of the demonstration of the above reaction, the CPC coagulation / separation, which has been possible for the first time under the condition of a high concentration of CPC of several percent in the solution and the coagulation temperature of 0 ° C. or lower, at a liquid temperature of about 10 to 30 ° C. This is possible even in a solution containing about 1,000 mg / L (about 0.1%) of CPC.

Therefore, according to the present invention, the following effects can be obtained. (1) Dilution with an enormous amount of water to suppress the influence on the wastewater treatment facility of the existing activated sludge system in the production factory is unnecessary, and the dilution water is saved and diluted. It is possible to avoid an increase in the treatment capacity of the wastewater treatment facility due to an increase in the amount of wastewater treatment due to.
(2) Equipment that requires enormous costs for equipment construction and maintenance such as ion exchange and cooling, and equipment that is complicated and difficult to manage can be eliminated.
(3) The above two typical effects can avoid unnecessary energy consumption and increase the contribution to a low-carbon society.

Embodiment 2. FIG.
FIG. 2 is a flowchart showing a CPC-containing waste water treatment apparatus according to Embodiment 2 of the present invention. The same or corresponding parts as those in FIG.
In the second embodiment, a rapid stirring tank 10 for introducing CPC-containing wastewater from the raw water inflow pipe 2 is installed in the preceding stage of the reaction tank 1 in the first embodiment, and the rapid stirring tank 10 is used for rapid stirring. The point that the stirrer 40 is installed, the halide salt is directly added to the rapid stirring tank 10 from the chemical supply equipment 3, and the stirrer 4 in the reaction tank 1 is used for slow stirring are described in the first embodiment. And very different.
The stirrers 4 and 40 may be mechanical stirring blades, but no other drive unit is required, and a fixed plate or the like may be installed in the tank to use a mixing flow rate. It is not something

  In the second embodiment described above, since the rapid stirring tank 10 is installed in the previous stage of the reaction tank 1, there is an effect that the mixing ratio of the CPC-containing wastewater and the halide salt is improved and the processing capacity is increased.

Example 1.
Example 1 as a result of experimentally operating the CPC-containing wastewater treatment apparatus according to the second embodiment will be described.
In Example 1, use square tank 0.5 m ³ as rapidly stirred tank 10, use square tank 5 m ³ as reaction vessel 1, the solid-liquid separation equipment 6 uses a circular tank of 5 m ^3, A reactant return pump (not shown) was installed in the reactant drawing tube 8 connected to the bottom of the circular tank, and these constituted a CPC removal step.
Further, as a chemical (halogenated salt) supplied from the chemical supply facility 3 to the rapid stirring tank 10, an aqueous solution of 50% potassium iodide (KI) was used.
And the CPC containing wastewater containing about 1000 mg / L of CPC was continuously supplied to the rapid stirring tank 10 with the submersible pump, and potassium iodide was added and processed with the monoflex pump. Table 1 shows the CPC removal result as an example of the processing performance.

  From the results of Table 1 above, it was confirmed that even the CPC of about 1000 mg / L, which is difficult with the conventional CPC removal technology, can be removed to a CPC concentration of several hundred mg / L by the present invention.

Embodiment 3 FIG.
FIG. 3 is a flowchart showing a CPC-containing wastewater treatment apparatus according to Embodiment 3 of the present invention. In the third embodiment, the rapid stirring tank 10 and the cooling equipment 11 are installed in the previous stage of the reaction tank 1, and a KI (potassium iodide) solution is supplied from the chemical supply equipment 3 to both the rapid stirring tank 10 and the reaction tank 1. The point of the configuration for injection is greatly different from those of the first and second embodiments.

According to the third embodiment, when the KI solution is injected from the chemical supply facility 3 into the CPC-containing wastewater of the raw water inflow pipe 2, the mixture of the KI solution and the CPC-containing wastewater flows into the rapid stirring tank 10. After being rapidly stirred by the rapid stirrer 40, the liquid mixture in the rapid stirring tank 10 is cooled by the cooling equipment 11 in the process of being transferred to the reaction tank 1 and flows into the reaction tank 1.
Therefore, the liquid temperature of the liquid mixture flowing into the reaction tank 1 can be lowered, and the reaction efficiency in the reaction tank 1 is improved.

  That is, the CPC removal efficiency of the CPC-containing wastewater deteriorates as the water temperature rises as can be seen from Table 1. As a countermeasure against this, in the present invention, as described above, the cooling equipment 11 is installed in the previous stage of the reaction tank 1 to cool the mixed liquid of the CPC-containing wastewater and the KI solution, and the cooled mixed liquid flows into the reaction tank 1. Therefore, the reaction efficiency is improved in the reaction tank 1.

  In the third embodiment, the cooling facility 11 may cool the raw water (CPC-containing wastewater) itself or the entire treatment apparatus, and the cooling means may use natural heat radiation, heat exchange using a chiller, a cooling tower, or the like. But it does n’t matter what means.

Embodiment 4 FIG.
FIG. 4 is a flowchart showing a CPC-containing waste water treatment apparatus according to Embodiment 4 of the present invention. The same or corresponding parts as those in FIGS.
In the fourth embodiment, a cooling facility 11 is installed in the raw water inflow pipe 2 which is a CPC-containing wastewater inflow line, and potassium bromide (KBr) is used as a halide salt to be injected from the chemical supply facility 3 into the CPC-containing wastewater. Further, the point that the submersible pump 30 is used as a stirrer in the reaction tank 1 is greatly different from the second and third embodiments.
Example 2 as a result of actually operating the CPC-containing wastewater treatment apparatus according to Embodiment 4 configured as described above will be described below.

Example 2
In Example 2, the CPC concentration of raw water is 924 mg / L, and the dissolution concentration of KBr injected into the raw water is 30%.
Similarly to KI, KBr reacts with CPC, and CPBr is generated and solidified by the oxidizing power of bromine (Br). Table 2 shows the results of operating the CPC-containing wastewater treatment apparatus of Embodiment 4.

As shown in Table 2, the removal performance of CPC was higher than that of KI with respect to the dose rate of KBr, but since the CPC concentration of treated water was low, it was confirmed that KBr can be used in the same manner as KI.
Therefore, in the case of the fourth embodiment, the same effects as those of the third embodiment are obtained.

Embodiment 5 FIG.
FIG. 5 is a flowchart showing a CPC-containing wastewater treatment apparatus according to Embodiment 5 of the present invention. The same or corresponding parts as in FIG.
In the fifth embodiment, a plurality of bypass plates 12 are arranged in the reaction tank 1 shown in the fourth embodiment (FIG. 4) to form a bypass channel for stirring the mixed solution that meanders in the vertical direction. The point which differs in the point which returns and circulates a part of liquid mixture of the said reaction tank 1 to the CPC containing waste_water | drain inflow line (raw water inflow pipe | tube 2) of the cooling equipment 11 front | former | stage is a big difference.

  In the fifth embodiment, as the return / circulation unit for the mixed solution, a return pipe 5 for transferring the mixed solution in the reaction tank 1 to the solid-liquid separation facility 6 and a raw water inflow pipe 2 in the preceding stage of the cooling facility 11 are returned. 13, an opening / closing valve 14, a circulation pump 16, and an opening / closing valve 15 are arranged on the return main pipe 13 from the side of the advection pipe 5, and the bottom of the reaction tank 1 and the return main pipe 13 are connected by a return branch pipe 13 a. The return branch pipe 13a is connected to the open / close valve 17, the bottom of the rapid stirring tank 10 and the return main pipe 13 are connected by the return branch pipe 13b, and the return branch pipe 13b is also connected to the open / close valve 18b. Is installed.

According to Embodiment 5 configured in this manner, a part of the effluent mixed liquid from the reaction tank 1 is returned to the rapid stirring tank 10 or the CPC-containing drainage inflow line (raw water inflow pipe 2) by the circulation pump 16. The reaction product (solid matter) in the returned effluent mixture serves as a nucleus, which facilitates solidification of the reaction product produced by Formula 1, lowers the CPC concentration of the treated water, and stirs the mixture and solid-liquid separation. There is an effect that the processing time can be shortened and the processing efficiency is improved.
Further, since the mixed liquid flowing into the reaction tank 1 from the rapid stirring tank 10 is stirred by flowing meandering between the bypass plates 12 in the reaction tank 1, the mixed liquid in the reaction tank 1 is stirred by power. There is also an effect that an agitator can be eliminated.

Example 3
Table 3 shows the results when the CPC-containing wastewater treatment apparatus according to Embodiment 5 was actually operated and a part of the effluent mixed solution in the reaction tank 1 was returned to the CPC-containing wastewater inflow line.

As can be seen from Table 3, it can be confirmed that the CPC removal performance is reduced even when the treatment amount is increased by returning the mixed solution.
Further, the mixed liquid circulation line (return main pipe 13, return branch pipes 13a and 13b) in the fifth embodiment has an effect of effectively starting up the operation of the apparatus by starting the circulation pump 16. That is, when restarting a device that has been temporarily stopped due to the treatment of CPC-containing wastewater with a high water temperature, only the circulation pump is started first, and after the water temperature of the entire device is lowered, it is possible to introduce CPC-containing wastewater. I can drive.

Embodiment 6 FIG.
FIG. 6 is a flowchart showing a CPC-containing wastewater treatment apparatus according to Embodiment 6 of the present invention. The same parts as those in FIG.
In the sixth embodiment, an aeration device 19 for stirring the mixed liquid is installed in the reaction tank 1 in the second embodiment, and the solidified product precipitated and separated by the solid-liquid separation facility 6 is rapidly stirred tank 10 or CPC. It is configured to return to the contained drainage inflow line.
In addition, although the aeration apparatus 19 is a stirring method by aeration, an aspirator may be used, and an air inflow method is not limited.

  In the sixth embodiment, as the solidified material returning means of the solid-liquid separation facility 6, the bottom of the solid-liquid separation facility 6 and the raw water inflow pipe 2 are connected by the return main tube 20, and the solid-liquid separation is performed on the return main tube 20. The return pump 21 and the opening / closing valve 22 are arranged from the facility 6 side, the bottom of the rapid stirring tank 10 and the return main pipe 20 are connected by the return branch pipe 23, and the return branch pipe 23 is provided with the opening / closing valve 24. It is. Accordingly, the solid-liquid separation facility 6 separates the precipitate by starting the return pump 21 with one of the on-off valve 22 of the return main pipe 20 and the on-off valve 24 of the return branch pipe 23 opened and the other closed. The solidified product can be returned to the raw water inflow pipe 2 or the rapid stirring tank 10.

  By returning the solidified material of the solid-liquid separation facility 6 to the raw water inflow pipe 2 or the rapid stirring tank 10 in this way, the concentration of the reactant becomes relatively high, and the capacity of the return pump 21 can be reduced. Can be achieved.

Embodiment 7 FIG.
FIG. 7 is a flowchart showing a CPC-containing wastewater treatment apparatus according to Embodiment 7 of the present invention. The same parts as those in FIG.
In this Embodiment 7, while installing the cooling equipment 11 in the raw | natural water inflow pipe 2 in the said Embodiment 6, the solid-liquid separation equipment 6 installed separately from the reaction tank 1 in the said Embodiment 6 is made unnecessary. A cylindrical rotating body that is disposed in the reaction tank 1 in a vertical direction, and is provided with a plurality of separation blades 25a spaced around the circumference and with a gap (slit) therebetween to separate a mixed liquid containing a solidified product into a solid-liquid separation. 25 and a driving means 25b for rotating the cylindrical rotating body 25 at 60 revolutions / minute or less are installed as a solid-liquid separation facility, and a part of the solidified material separated in the reaction tank 1 is fed into raw water by a return pump 21. It is configured to return to the inflow pipe 2 or the rapid stirring tank 10.

  In the seventh embodiment configured as described above, a solid-liquid separation facility separate from the reaction tank 1 can be eliminated as described above, and the cylindrical rotating body 25 is rotated in the reaction tank 1 to rotate the cylinder. The mixed liquid containing the solidified material inside the cylindrical rotator 25 is caused to substantially rotate along with the cylindrical rotator 25 to prevent the solidified substance contained in the mixed liquid from flowing out of the cylindrical rotator 25, The solidified material held inside the rotating body 25 quickly settles down to the lower part of the water tank 1, while the treated water separated from the solidified material passes through the gap (slit) of the separation blade 25a and flows out. By returning a part of the solid separated after liquid separation to the raw water inflow pipe 2 or the rapid agitation tank 10 by the return pump 21, the same effect as in the sixth embodiment is obtained.

Embodiment 8 FIG.
FIG. 8 is a flowchart showing a CPC-containing wastewater treatment apparatus according to Embodiment 8 of the present invention.
In the eighth embodiment, the rapid stirring tank 10 is installed in the preceding stage of the reaction tank 1 and a part of the mixed solution stored in the mixed solution receiving tank 26 is placed in the subsequent stage of the cooling equipment 11 installed in the raw water inflow pipe 2. Alternatively, the rapid stirring tank 10 is returned and circulated by the circulation pump 16.

  In this Embodiment 8, the reaction tank 1 has a two-tank structure of a first-stage reaction tank 1A and a second-stage reaction tank 1B, and a stirrer 4 and 41 are installed in each of the first-stage reaction tank 1A and the second-stage reaction tank 1B. In addition, a mixed solution receiving tank 26 was installed in the subsequent stage of the subsequent reaction tank 1B, and a stirrer 42 was also installed in the mixed solution receiving tank 26. Further, the bottom of the mixed liquid receiving tank 26 and the raw water inflow pipe 2 downstream of the cooling facility 11 are connected by a return main pipe 13, and the circulation pump 16 and the opening / closing valve 15 are arranged in the return main pipe 13 from the mixed liquid receiving tank 26 side. At the same time, a return branch pipe 13b is connected to the bottom of the rapid stirring tank 10 and the return main pipe via an on-off valve 18, and a solid-liquid separation facility 6 is installed in the subsequent stage of the mixed liquid receiving tank 26. The mixed solution receiving tank 26 may have any shape as long as it can temporarily store the mixed solution. The solid-liquid separation facility 6 separates the solidified material and the treated water, such as a centrifuge and a screen, and a mixed solution receiving tank 26 for temporarily storing the mixed liquid flowing in from the reaction tank 1 at the rear stage of the reaction tank 1. The type of equipment is not limited as long as it is set apart.

  In the eighth embodiment, the cooled mixed liquid sequentially flowing into the rapid stirring tank 10 and the reaction tanks 1A and 1B having the two-tank structure are stirred by the stirrers 40, 4 and 41, respectively. Since it is made to flow into the mixed liquid receiving tank 26 and further stirred by the stirrer 42, the mixed liquid after the stirring is returned and circulated from the mixed liquid receiving tank 26 to the raw water inflow pipe 2 or the rapid stirring tank 10 by the circulation pump 16. There is an effect that can be further improved. In addition, when a centrifuge is used as the solid-liquid separation facility 6, the reaction product (solidified product) can be controlled to a concentrated state or a dehydrated cake state according to the mechanical conditions (centrifugal effect, differential speed, etc.) of the centrifuge. The separation liquid is also good, and there is an effect that the maintainability is improved.

Embodiment 9 FIG.
FIG. 9 is a flowchart showing a CPC-containing wastewater treatment apparatus according to Embodiment 9 of the present invention.
In the ninth embodiment, a cooling facility 11 is installed in the raw water inflow pipe 2, and a halide salt is injected from the chemical supply facility 3 into the CPC-containing wastewater flowing into the rapid stirring tank 10 through the cooling facility 11 and stirred. In the CPC-containing wastewater treatment apparatus in which the mixed liquid is agitated and mixed by the machine 40, the mixed liquid is transferred to the reaction tank 1 and stirred by the stirrer 4, and the mixed liquid after the stirring flows into the solid-liquid separation facility 6. A membrane filtration device is installed in the solid-liquid separation facility 6 in which a mixed liquid suction pump 30 is installed at the bottom of 1 and the mixed liquid in the reaction tank 1 is supplied through a mixed liquid supply pipe 31 connected to the pump 30. 27, and a part of the high-concentration mixed liquid after solid-liquid separation by the membrane filtration device 27 is returned to the raw water inflow pipe 2 or the rapid stirring tank 10 after the cooling equipment 11 by the return pump 21. It is.

  As a means for returning the high-concentration mixed liquid, in the ninth embodiment, the secondary side of the membrane filtration device 27 in the solid-liquid separation facility 6 and the raw water inflow pipe 2 downstream of the cooling equipment 11 are connected by a return main pipe 20. The return pump 21 and the open / close valve 22 are installed in the return main pipe 20, the rapid stirring tank 10 and the return main pipe 20 are connected by the return branch pipe 23, and the open / close valve 24 is installed in the return branch pipe 23. The configuration is as follows.

  According to this Embodiment 9, since the membrane filtration apparatus 27 installed in the solid-liquid separation facility 6 after the reaction tank 1 has very good solid-liquid separation performance, the reaction product (solidified product) is treated as treated water. There is an effect that CPC removal efficiency is improved with almost no outflow.

Embodiment 10 FIG.
FIG. 10 is a flowchart showing a CPC-containing wastewater treatment apparatus according to Embodiment 10 of the present invention. The same parts as those in FIG.
In this Embodiment 10, the reaction of Formula 1 and the removal of the reaction product (solid matter) can be performed in the reaction tank 1 by intermittently driving the stirrer 4 of the reaction tank 1 in the aforementioned Embodiment 2. It is a configuration. The reaction tank 1 is connected to an upper treated water discharge pipe 7A and a lower solidified material extraction pipe 8A, respectively, and open / close valves 33 and 32 are connected to the treated water discharge pipe 7A and the solidified material extraction pipe 8A. The installed configuration. It should be noted that the extraction of the solidified material from the solidified material extraction tube 8A may be performed by opening / closing an electric valve or the like, or may be performed by a pump or the like.

Next, the operation of the CPC-containing wastewater treatment apparatus according to Embodiment 10 will be described.
A mixture of halogenated salt added from a chemical supply facility 3 to a certain amount of CPC-containing wastewater flowing through the raw water inflow pipe 2 is introduced into the reaction tank 1 (injection process), and the agitator 4 is used to sufficiently perform the reaction. After stirring (reaction process) and the reaction product (solidified product) is sufficiently formed in the reaction tank 1, the stirrer 4 is stopped to precipitate the reaction product (sedimentation process) and separated from the treated water (discharge process). The halide salt may be added directly to the reaction tank 1 even if it is added to the raw water inflow pipe 2 (CPC-containing drainage inflow line). The stirring method by the stirrer 4 is not limited as long as it does not hinder the sedimentation of the reaction product in the sedimentation step and the discharge of the treated water and the reaction product in the discharge step. The method of discharging treated water and reactants is not limited as long as the solid-liquid interface formed by the sedimentation process is not broken.

  The embodiment 10 described above is a process by batch operation, and the advantage is that the reaction mixture can be kept in the reaction vessel 1 until the reaction between CPC and the halide salt is completed, so that the reaction efficiency is improved. It is. In addition, since all the steps are performed only in the reaction tank 1, it is possible to eliminate the need for returning the reactants and separate solid-liquid separation equipment, thereby saving energy.

Embodiment 11 FIG.
FIG. 11 is a flowchart showing a CPC-containing wastewater treatment apparatus according to Embodiment 11 of the present invention. In the eleventh embodiment, continuous reaction of CPC-containing wastewater is enabled in one reaction tank 1. In the eleventh embodiment, a cylindrical partition member 34 surrounding the stirring blade is installed in the reaction tank 1 so as not to hinder the rotation of the stirring blade of the stirrer 4. 1, a stirring zone 1A and a solid-liquid separation zone 1B are formed.

  In the eleventh embodiment, a mixed solution of CPC-containing wastewater and a halide salt is introduced into the stirring zone 1A of the reaction tank 1, and in the stirring zone 1A, the reaction is promoted by the stirrer 4 so that the reaction product (solidified product) ) Is generated. The produced reaction product is allowed to settle in the solid-liquid separation zone 1B. The settled reactant is discharged out of the system by a discharge means such as a reactant extraction valve or a submersible pump (both not shown) provided at the bottom of the reaction tank 1.

According to the eleventh embodiment described above, since the mixed liquid of CPC-containing wastewater and halide salt can be continuously processed by one reaction tank 1, the site area of the wastewater treatment facility can be reduced, and the mechanical equipment Therefore, the facility cost can be reduced.

It is a flowchart which shows the basic CPC containing waste water treatment equipment by Embodiment 1 of this invention. It is a flowchart which shows the CPC containing waste water treatment equipment by Embodiment 2 of this invention. It is a flowchart which shows the CPC containing waste water treatment equipment by Embodiment 3 of this invention. It is a flowchart which shows the CPC containing waste water treatment equipment by Embodiment 4 of this invention. It is a flowchart which shows the CPC containing waste water treatment equipment by Embodiment 5 of this invention. It is a flowchart which shows the CPC containing waste water treatment equipment by Embodiment 6 of this invention. It is a flowchart which shows the CPC containing waste water treatment equipment by Embodiment 7 of this invention. It is a flowchart which shows the CPC containing waste water treatment equipment by Embodiment 8 of this invention. It is a flowchart which shows the CPC containing waste water treatment equipment by Embodiment 9 of this invention. It is a flowchart which shows the CPC containing waste water treatment equipment by Embodiment 10 of this invention. It is a flowchart which shows the CPC containing waste water treatment apparatus by Embodiment 11 of this invention.

DESCRIPTION OF SYMBOLS 1 Reaction tank 1A Stirring zone 1B Solid-liquid separation zone 2 Raw water inflow pipe 3 Chemical supply equipment 4 Stirrer 5 Advection pipe 6 Solid-liquid separation equipment 7, 7A Treated water discharge pipe 8, 8A Reactant extraction pipe 9 Connection pipe 10 Rapid stirring Tank 10A Mixed liquid overflow tank 11 Cooling equipment 12 Bypass plate 13 Return main pipes 13a, 13b Return branch pipes 14, 15 Open / close valve 16 Circulating pumps 17, 18 Open / close valve 19 Aeration device 20 Return main pipe 21 Return pump 22 Open / close valve 23 Returning branch pipe 24 On-off valve 25 Cylindrical rotating body 25a Separating blade 25b Driving means 26 Mixed liquid receiving tank 27 Membrane filtration device 30 Submersible pump 31 Mixed liquid supply pipe 32, 33 On-off valve 34 Partition members 40, 41, 42 Stirrer

Claims (4)

Add halogenated salt to CPC-containing wastewater,
A CPC-containing wastewater treatment apparatus, wherein a reaction product of CPC and a halide salt is generated and separated. A reaction vessel for introducing and stirring CPC-containing wastewater;
Chemical addition equipment for adding halides to CPC-containing wastewater,
A CPC-containing wastewater treatment apparatus comprising: a solid-liquid separation tank for separating a reaction product of CPC and a halide salt from a mixed liquid in the reaction tank. The reactor is
A CPC-containing wastewater treatment apparatus according to claim 2, further comprising a rapid stirring tank. The halogenated salt is
It is potassium iodide or potassium bromide. The CPC containing waste water treatment apparatus in any one of Claims 1-3 characterized by the above-mentioned.

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