JP2001300535A - Method for refining liquid - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for refining liquid, by which the refined liquid of the desired quality can be continuously withdrawn at the prescribed speed uninterruptedly while keeping in the respective fixed values or higher the removal ratio of an ionic material from an ionic material-containing liquid and the recovery ratio of the refined liquid after the ionic material is removed and which is usable on a commercial base. SOLUTION: This method for refining liquid comprises separating the ionic material- containing undiluted solution (L) into the refined liquid (L1) poor in ionic material content and a high concentration liquid (L2) rich in ionic material content by using a refining apparatus provided with liquid-passable condensers (1). The adsorption of the ionic material by an electrical charge and the desorption of the adsorbed ionic material by a short circuit or a counter electrical charge are carried out at the prescribed pattern by using three or more condensers (1) while interlocking with the connection among the condensers (1) and the switchover between introduction of the solution (L) and withdrawal of the liquids (L1 and L2) with respect to the respective condensers (1). As a result, the solution (L) is continuously refined at the prescribed flow speed and the liquid (L1) of the prescribed quality and the liquid (L2) are continuously withdrawn at the prescribed respective flow speeds.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a method for purifying an undiluted solution containing an ionic substance by using a purification apparatus provided with a flow-through type electric double layer capacitor, and a purified liquid having a reduced ratio of the ionic substance. The present invention relates to a method for purifying a liquid to be separated into a high-concentration liquid having an increased proportion of a substance.

[0002]

2. Description of the Related Art A method of removing an ionic substance from water containing an ionic substance using an electric double layer capacitor and utilizing electrostatic force (for example, a method of desalinating water containing salt) is known. I have.

US Pat. No. 5,192,432 and US Pat. No. 5,196,115 disclose a flow-through type capacitor used in a column for constant charge chromatography for purifying a liquid, which comprises a first conductive support layer and a first conductive support layer. High surface area conductive layer,
Spiral a plurality of adjacent layers including a first non-conductive porous spacer layer, a second conductive support layer, a second high surface area conductive layer, a second non-conductive porous spacer layer, etc. A flow-through condenser wound in a zigzag is shown. The specification also discloses that the condenser can be used for purifying water containing an ionic substance such as sodium chloride.

Japanese Patent Application Laid-Open No. 5-258 filed by the present applicant
Japanese Patent No. 992 (corresponding to U.S. Pat. No. 5,200,068) discloses a flow-through type capacitor in which washer-type electrodes are stacked in addition to a wound-type flow-through type capacitor.

JP-A-6-325 filed by the applicant of the present invention
No. 983 (corresponding to US Pat. No. 5,538,611) discloses that an activated carbon layer mainly composed of activated carbon having a high specific surface area is disposed with a separator made of an electrically insulating porous liquid-permeable sheet interposed therebetween. A flat-plate, liquid-flow type electric double-layer capacitor having a configuration in which a collecting electrode is disposed outside and a pressing plate is disposed outside the collecting electrode is shown. In addition, while passing a liquid containing an ionic substance through the flat plate-shaped liquid-flow type electric double layer capacitor, the application of a DC constant voltage to the collector and the short-circuit or reverse connection between the collectors are alternately performed. A method of treating the liquid to be repeated is shown.

[0006] Japanese Patent Application No. 9-509 filed by the present applicant
No. 880 (corresponding to U.S. Pat. No. 5,748,437) discloses a flow-through type capacitor used in a column for constant charge chromatography for purifying a liquid, comprising a first conductive support layer and a first conductive support layer. A plurality of adjacent layers including a surface area conductive material layer, a first non-conductive support layer, a second conductive support layer, a second high surface area conductive material layer, a spacer for the second non-conductive support layer, and the like. A liquid-passing type capacitor in which the groups are stacked in a washer type or spirally wound is shown.

[0007] The present applicant has disclosed in Japanese Patent Application Laid-Open No. 2000-9116.
In Japanese Patent Application Publication No. 9, a patent application is filed for a flow-through capacitor in which all of the separator, the electrode and the collector are formed of a folded or flat sheet and a method of treating a liquid using the same.

[0008]

All of the devices and methods of the above-cited documents use a flow-through condenser and use electrostatic force to remove the ionic substance from the liquid containing the ionic substance. Is what you do. All of these documents are related to the applicant or the applicant's application in the United States.

[0009] However, these documents only show the principle and structure (in a single machine, the product liquid from which the ionic substance has been removed will intermittently appear). A method of operating the apparatus in consideration of the removal rate of the important ionic substance and the recovery rate of the product liquid after the removal has not yet been sufficiently disclosed.

[0010] Under such a background, the present invention can secure the removal rate of the ionic substance from the liquid containing the ionic substance at a certain value or more, and can maintain the recovery rate of the purified liquid after the removal at a certain value. It is an object of the present invention to provide an industrial purification treatment method which can ensure the above and can continuously extract a purified liquid of a desired quality at a predetermined speed without interruption. .

[0011]

According to the method for purifying a liquid of the present invention, an undiluted solution (L) containing an ionic substance is converted into an ionic liquid using a purifying apparatus provided with a flow-through type electric double layer capacitor (1). Upon separation into a purified liquid (L ₁ ) with a reduced proportion of ionic substances and a high-concentration liquid (L ₂ ) with an increased proportion of ionic substances,
The use of three or more capacitors (1) and the adsorption of ionic substances by charging and the desorption of ionic substances by short-circuiting or reverse charging can be performed by each capacitor (1).
In a predetermined pattern while interlocking with the connection between and switching between the introduction and the derivation of the liquid to each condenser (1), the stock solution (L) is continuously processed at a predetermined flow rate, It is characterized in that a purified liquid (L ₁ ) and a high-concentration liquid (L ₂ ) of a predetermined quality are continuously taken out at a predetermined flow rate.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail. For simplicity of explanation or for easy understanding, the ionic substance is adsorbed and removed by `` desalting '', the adsorbed ionic substance is desorbed by `` washing '', and the purified liquid (L ₁ ) is used. "Product liquid",
The high concentration liquid (L ₂ ) may be referred to as “effluent”.

<< Purification Treatment Method >> The liquid purification treatment method of the present invention uses a purification apparatus provided with a flow-through type electric double layer capacitor (1) to convert an undiluted solution (L) containing an ionic substance into an ionic substance. The present invention is applied to a method of separating into a purified liquid (L ₁ ) having a reduced substance ratio and a high-concentration liquid (L ₂ ) having an increased ionic substance ratio. Hereinafter, a purification treatment method will be described first, and a purification device will be described later.

<Liquid and ionic substances> The liquid purification treatment includes purification treatment such as water purification, seawater desalination, and denitrification of waste liquid. In addition, recovery of precious metals, purification of inorganic salts, It also includes processes for capturing and recovering ionic substances such as quantification of dissolved ionic substances. Examples of the liquid include those using water or other inorganic solvents, organic solvents, or a mixed solvent thereof as a medium, such as blood. Ionic substances include metal salts, amine salts,
Examples thereof include an electrolyte and a chargeable substance which can be dissociated in a liquid such as an ammonium salt, an inorganic acid, and an organic acid.

<Number of Capacitors (1), Adsorption and Desorption> In the present invention, three or more capacitors (1), for example, 3
Or four groups. By using three or more capacitors (1), continuous purification can be achieved.

The adsorption is carried out by energizing and charging the condenser (1) and passing the liquid. The desorption of the adsorbed ionic substance is as follows: short-circuit between the electrodes of the capacitor (1) adsorbing the ionic substance, and discharge the charged electric energy from the capacitor (1); This can be done by short-circuiting the electrodes of the capacitor (1) that adsorbs the substance, passing a current in the opposite direction to that during charging, and discharging the charged electrical energy from the capacitor (1). it can.

<Three tower type / Part 1> Condenser (1)
When three groups of A, B and C are used, typically, a six-stage operation of “adsorption 1 → adsorption 1 → desorption 1 → desorption 2 → adsorption 2 → adsorption 2” is performed by A, B , And C, it is preferable to carry out the process while shifting two stages in this order.

FIGS. 1 and 2 show three capacitors.
The flow of liquid and the role of each process during operation of the refining apparatus when (1) is used (three-column type) are shown. The operation at this time includes a two-stage adsorption (desalting) step and a two-step desorption (washing) step.

(A) Adsorption Step The adsorption step is composed of a total of four stages, two stages for adsorption 1 and two stages for adsorption 2. The adsorption 1 is a step of removing (desalting) an ionic substance by passing a stock solution (L). Adsorption 2
This is a step of removing (desalinating) low-concentration ionic substances that could not be completely removed by adsorption 1 (the first stage of desalting) of another condenser (1). In processing a liquid containing an ionic substance (stock solution (L)), both capacitors (1) are charged. By connecting two capacitors (1), adsorption 1
The liquid from which a considerable amount of the ionic substance has been removed is led to the adsorption 2. Therefore, the load on the adsorption 2 is extremely small.

At the end of the adsorption step, since the purity of the purified liquid (L ₁ ) (product purity) is determined by the concentration of the ionic substance at the outlet of the adsorption 2, the concentration of the ionic substance at the exit of the adsorption 2 is a predetermined value. The suction operation, that is, the charging may be terminated when the value exceeds the value. Alternatively, the end of charging may be determined based on the concentration of the ionic substance at the outlet of the adsorption 1 because the adsorption 1 mainly removes the ionic substance. Alternatively, the suction (charging) time may be determined based on the current value or voltage value of the capacitor (1) of the suction 1 and the suction 2 when charging.

(B) Desorption Step The desorption step comprises two steps, desorption 1 and desorption 2. Desorption 1 is a step of washing the ionic substance captured on the electrode of the condenser (1) with a stock solution (L). In the desorption 2, a part of the purified liquid (L ₁ ) (product liquid) is allowed to flow to further thoroughly wash the electrodes.

During the desorption step, the capacitor (1) is in a short-circuit state, so that the ionic substance is easily desorbed from the electrodes. Also, at this time, if a current is appropriately passed in the opposite direction to that during charging (if reverse charging is performed), desorption of the ionic substance from the electrode is further accelerated.

<Three tower type / Part 2> Condenser (1)
When three groups of A, B and C are used, typically, a three-stage operation of “adsorption 1 → adsorption 2 → desorption” is performed by A, B
For each of B and C, it is also possible to carry out the process while shifting one stage at a time in this order.

FIGS. 3 and 4 show three capacitors.
The flow of liquid and the role of each process during operation of the refining apparatus when (1) is used (three-column type) are shown. The operation at this time includes a two-stage adsorption (desalination) step and a one-step desorption (washing) step.

<Four-Tower Type> When four units of A, B, C, and D are used as the condenser (1), typically,
The four-stage operation of “Adsorption 1 → Adsorption 2 → Desorption 1 → Desorption 2”
For each of A, B, C, and D, the process is performed while shifting one stage at a time in this order.

FIGS. 5 and 6 show four capacitors.
The flow of water and the role of each process during the operation of the refining device when (1) is used (four-tower type) are shown. The operation at this time includes a two-stage adsorption (desalting) step and a two-step desorption (washing) step.

(A) Adsorption Step Adsorption 1 is a step of passing an undiluted solution (L) to remove (desalinate) ionic substances. The adsorption 2 is a step of using a cleaning solution for the other condenser (1) which is relatively close to the stock solution (L). The operation of the adsorption 2 also serves to secure the recovery rate.

(B) Desorption Step Desorption 1 is a step of washing the ionic substance trapped on the electrode with a desorbing liquid from another capacitor (1). Desorption 2
In, wash with undiluted solution (L). Although the capacitor (1) is in a short-circuit state during the desorption step, the desorption of the ionic substance from the electrode can be further accelerated by appropriately reverse charging as in the case of the three-tower type.

<Comparison between the three-column type and the four-column type> When the three-column type and the four-column type are compared, the three-column type (No. 1) is an operation pattern in which the adsorption step is emphasized, and the purified liquid ( L ₁ ) It can be said that this is an effective means for keeping the purity (product liquid purity) high. On the other hand, the three-tower type (No. 2) is an operation pattern in which the desorption stage is emphasized, and a relatively high recovery rate can be obtained.

The four-tower type is an operation pattern emphasizing the desorption stage, and can be said to be an effective means for keeping the state of the condenser (1) clean. In the four-tower system,
Relatively high recoveries can be obtained.

Typical load values are shown in FIGS. 1, 3 and 5
It is written in. In the three-column system shown in Fig. 1, undiluted solution (L) 1.5
The average load amount is a for a, and in the three-column system of FIG. 3, the average load amount is 0.33a for the undiluted solution (L) a,
In the four-column system of FIG. 5, the average load amount is 2.5a for the undiluted solution (L) 2.5a (represented per one inlet reference column, a is a constant).
The recovery rate of the purified liquid (L ₁ ) (product liquid) was 67 in the three-column system of FIG.
%, 80% for the three tower system of FIG. 3, and 81% for the four tower system of FIG.
become.

Therefore, an appropriate operation method may be selected in consideration of the properties of the undiluted solution (L), desalination performance, required liquid quality of the purified liquid (L ₁ ) (product liquid), and the like. The high-concentration liquid (L ₂ ) (effluent) may be discarded as an effluent, or an ionic substance may be collected from the waste liquid and reused as a collected product.

<< Purification Apparatus >> The above-mentioned purification treatment method is carried out using a purification apparatus equipped with a flow-through type electric double layer capacitor (1). The number of capacitors (1) should be three or more as described above.

As the flow-through type electric double layer capacitor (1), one having a conductive support layer (11), a high surface area conductive layer (12) and a non-conductive porous spacer layer (13) is used. Can be The apparatuses described in the prior art section (all of which are related to the applicant or the applicant's application in the United States of America) may also be used for the purification treatment method of the present invention. Can be.

The simplest structure of the capacitor (1) is "conductive support layer (11) / high surface area conductive layer (12) / non-conductive porous spacer layer (13) / high surface area conductive layer (13)". Layer (12) /
It has the configuration of the “conductive support layer (11)”. In practice, these are multiplexed to increase the efficiency. Conductive support layer (1
1) plays a role of a collector, the high surface area conductive layer (12) plays a role of adsorbing ionic substances, and the non-conductive porous spacer layer (13) plays a role of a separator.

Here, the conductive support layer (11) is, for example, an electric conductor such as a copper plate, an aluminum plate, a SUS plate, a carbon plate, or a foil-like graphite, and is made of a material having a high surface area and a conductive layer (12). Those capable of close contact are used. Usually, terminals (leads) are provided on the conductive support layer (11) to facilitate application. Conductive support layer
Although the thickness of (11) is not limited, a thickness of about 0.01 to 0.2 mm is often used.

As the high surface area conductive layer (12), for example, a layer mainly composed of activated carbon having a high specific surface area is suitably used. High specific surface area activated carbon has a BET specific surface area of 1000
m ² / g or more, preferably 1200 m ² / g or more, more preferably refer to 1300 m ² / g or more activated carbon. When the BET specific surface area is too small, the removal rate of the ionic substance when passing through the liquid containing the ionic substance decreases. BET
If the specific surface area is too large, the removal rate of the ionic substance tends to be rather lowered, so that it is not sufficient to increase the BET specific surface area more than necessary. The upper limit of the BET specific surface area is up to about 2500 m ² / g. The shape of the activated carbon to be used is arbitrary, such as powdery and granular, and fibrous. In the case of a powdery or granular form, it is used after being formed into a flat plate or a sheet. In the case of a fibrous form, it is used after being processed into a cloth. For the formation into a flat plate or a sheet, for example, powdered granular activated carbon is mixed with a binder component (polytetrafluoroethylene, phenol resin, carbon black, etc.) and / or a dispersion medium (solvent, etc.) and formed into a plate shape. From a suitable rolling or heat treatment. In the case of using a flat plate or a sheet, a perforation process can be performed on the plate if necessary. The thickness of the high surface area conductive layer (12) is 0.3 to 2
It is often about mm, especially about 0.5 to 1 mm, but is not necessarily limited to this range.

As the non-conductive porous spacer layer (13),
For example, filter paper, porous polymer membrane, woven fabric, non-woven fabric, etc.
A sheet made of an organic or inorganic sheet that allows easy passage of a liquid and has electrical insulation properties is used. The thickness of the non-conductive porous spacer layer (13) is suitably about 0.01 to 0.5 mm, especially about 0.02 to 0.3 mm.

<Operation> The principle of purifying a liquid containing an ionic substance using a liquid-flow type electric double layer capacitor will be described by taking a case where the liquid containing an ionic substance is a saline solution as an example.

At the time of applying a voltage, the sodium ions in the passed water are converted into the conductive support layer (11) (collector electrode) on the anode side.
Is electrically adsorbed to the high surface area conductive layer (12) (activated carbon layer) that is in contact with the surface, and the chlorine ion is conductively supported on the cathode side (11)
High surface area conductive layer in contact with (collector electrode) (12) (activated carbon layer)
And the salt concentration in the outlet water is significantly reduced. If water is continued, the adsorption of both ions to the high surface area conductive layer (12) (activated carbon layer) reaches saturation, so that the salt concentration at the outlet is close to that of the stock solution. If the cathode side and the anode side are short-circuited or reverse-connected at an appropriate timing, the sodium ions and chlorine ions adsorbed on the high surface area conductive layer (12) (activated carbon layer) are desorbed, and A saline solution having a concentration much higher than the salt concentration is discharged from the outlet.

[0041]

The present invention will be further described with reference to the following examples.

Example of Apparatus FIG. 7 shows a flow-through type electric double layer capacitor (1) used in the embodiment.
FIG. In FIG. 7, (14) is a holding plate, (15) is a gasket, (16) is a liquid inlet, (17) is a liquid outlet, and (18) is a bolt hole. Insert the bolt hole (18) into the holding plate (14), (14)
Bolts for fastening the spaces and nuts used with the bolts are not shown.

As the conductive support layer (11) (collector electrode), foil-like graphite having a thickness of 125 μm was used. A liquid passage hole (11a) having a diameter of about 1 mm is formed in the lower half of one collector electrode, and a similar liquid passage hole (1a) is formed in the upper half of the other collector electrode.
1a) is drilled. Each of these collector electrodes is provided with a terminal (11b).

The high surface area conductive layer (12) is a layer made of fibrous activated carbon in a plate shape and has a BET specific surface area of 1500.
m ² / g, size 120 mm × 120 mm, thickness 0.38 mm, specific gravity 0.
Two of 47 sheets were used. The activated carbon weight of the two high surface area conductive layers (12) was 5.2 g.

As the non-conductive porous spacer layer (13),
A filter paper having a thickness of about 0.2 mm was used.

Example 1 Purification treatment was performed according to FIG. 1 and FIG. 2 using a purification apparatus provided with three condensers (1). The setting of the flow rate and the switching of the flow path were performed using a pump and valves not shown. Switching from adsorption to desorption in a certain capacitor (1) was performed by a short circuit.

Two terminals are connected to the conductive support layer (11) (collector electrode).
It was connected to a volt DC power supply and applied. In FIG.
The flow rate is a = 15 ml / min (the introduced amount of stock solution (L) is 1.5a = 2
2.5 ml / min), and the required time for each of the steps I, II, III, IV, V and VI was 10 minutes. As the stock solution (L), a saline solution having a concentration of 10 mmol / l was used. Table 1 shows the results.

[0048]

[Table 1]  Purified liquid (L ₁ ) High concentration liquid (L ₂ )  Flow NaCl concentration Flow NaCl concentration(ml / min) (mmol / l) (ml / min) (mmol / l)  1 in Fig. 1 15.0 1.6 7.5 26 II in Fig. 1 14.8 1.6 7.7 26 III in Fig. 1 15.2 1.8 7.3 26 IV in Fig. 1 15.4 1.8 7.1 27 V in Fig. 1 14.8 1.5 7.7 26VI in Fig. 1 14.8 1.5 7.7 26  (Average) 15.0 1.6 7.5 26  (Note) The NaCl concentration is the value for the liquid obtained in 10 minutes.

As shown in Table 1, when three condensers (1) were used, the purified liquid (L ₁ ) and the highly concentrated liquid (L ₂ ) were always kept at a constant flow rate.
Is obtained, and at this time, the desalting rate of the purified liquid (L ₁ ) is 100.
× (10−1.6) / 10 = 84%, the recovery rate of the purified liquid (L ₁ ) was 100 ×
15.0 / (15.0 + 7.5) = 67%, the concentration of high concentration liquid (L ₂ ) is 1
It can be seen that 00 × 26/10 = 260%. And it turns out that the desalting rate of the purified liquid (L ₁ ) is particularly good.

Example 2 Purification was performed according to FIGS. 3 and 4 using a purification apparatus having three condensers (1). The setting of the flow rate and the switching of the flow path were performed using a pump and valves not shown. Switching from adsorption to desorption in a certain capacitor (1) was performed by a short circuit.

The terminal to the conductive support layer (11) (collector electrode) is
It was connected to a volt DC power supply and applied. In FIG.
The flow rate is a = 20 ml / min (the introduction amount of the stock solution (L) is also a = 20 ml / min)
/ min), and the required time for each of the steps I, II and III was 10 minutes. As the stock solution (L), a saline solution having a concentration of 10 mmol / l was used. The result at this time is the flow rate of the purified liquid (L ₁ ): 16 ml / min on average The NaCl concentration of the purified liquid (L ₁ ): 2.0 mmol / l on average The flow rate of the high concentration liquid (L ₂ ): 4.0 ml on average / min NaCl concentration of high concentration liquid (L ₂ ): 42 mmol / l on average, and desalting rate of purified liquid (L ₁ ) is 100 × (10-2.0) / 10 = 8
0%, the recovery rate of the purified liquid (L ₁ ) is 100 × 16 / (16 + 4) = 80
%, The concentration of the high concentration liquid (L ₂ ) was 100 × 42/10 = 420%.

Example 3 Purification treatment was performed according to FIGS. 5 and 6 using a purifying apparatus having four condensers (1). The setting of the flow rate and the switching of the flow path were performed using a pump and valves not shown. Switching from adsorption to desorption in a certain capacitor (1) was performed by a short circuit.

Two terminals are connected to the conductive support layer (11) (collector electrode).
It was connected to a volt DC power supply and applied. The flow velocity in FIG.
= 15ml / min (Introduction of stock solution (L) is 2.5a = 37.5ml / mi
n), and the required time for each of the steps I, II, III and IV was 10 minutes. The stock solution (L) has a concentration of 10 mmol / l
Was used. Table 2 shows the results.

[0054]

[Table 2]  Purified liquid (L ₁ ) High concentration liquid (L ₂ )  Flow NaCl concentration Flow NaCl concentration(ml / min) (mmol / l) (ml / min) (mmol / l)  I 30.0 2.0 7.5 40 in FIG. 5 II 31.0 2.2 6.5 45 in FIG. 5 III 31.0 2.1 6.5 47 in FIG.IV in Fig. 5 30.0 2.0 7.5 42  (Average) 30.5 2.1 7.0 43.5  (Note) The NaCl concentration is the value for the liquid obtained in 10 minutes.

As can be seen from Table 2, when four condensers (1) were used, the purified liquid (L ₁ ) and the highly concentrated liquid (L ₂ ) were always kept at a constant flow rate.
Is obtained, and at this time, the desalting rate of the purified liquid (L ₁ ) is 100.
× (10-2.1) / 10 = 79%, the recovery rate of the purified liquid (L ₁ ) is 100 ×
30.5 / (30.5 + 7.0) = 81%, the concentration of high concentration liquid (L ₂ ) is 1
It can be seen that 00 × 43.5 / 10 = 435%. And
It can be seen that the recovery rate of the purified liquid (L ₁ ) is particularly good.

[0056]

According to the present invention, it is possible to secure the removal rate of the ionic substance from the liquid containing the ionic substance at a certain value or more, and to achieve the recovery rate of the purified liquid after the removal at a certain value or more. That a purified liquid of a desired quality can be continuously taken out at a predetermined speed without interruption, and that an industrial purification process can be performed. It has the effect.

[Brief description of the drawings]

Fig. 1 When three capacitors (1) are used (three tower type)
FIG. 4 is an explanatory diagram showing a flow of a liquid during operation of the purification device of FIG.

Fig. 2 When three capacitors (1) are used (three tower type)
It is an explanatory view showing a role for each process at the time of operation of a purification device.

FIG. 3 When three capacitors (1) are used (three tower type)
FIG. 4 is an explanatory diagram showing a flow of a liquid during operation of the purification device of FIG.

Fig. 4 When three capacitors (1) are used (three tower type)
It is an explanatory view showing a role for each process at the time of operation of a purification device.

Fig. 5 When four capacitors (1) are used (four tower type)
FIG. 4 is an explanatory diagram showing a flow of a liquid during operation of the purification device of FIG.

[Fig. 6] When four capacitors (1) are used (four tower type)
It is an explanatory view showing a role for each process at the time of operation of a purification device.

FIG. 7 is a flow-through type electric double layer capacitor used in Examples.
It is an exploded view of (1).

[Explanation of symbols]

(1) ... condenser, (11) ... conductive support layer, (11a) ... liquid passage hole, (11b) ... terminal, (12) ... high surface area conductive layer, (13) ... non-conductive porous spacer layer , (14) ... holding plate, (15) ... gasket, (16) ... liquid inlet, (17) ... liquid outlet, (18) ... bolt hole, (L) ... stock solution, (L ₁₎ ... purified solution, ( L ₂ )… High concentration liquid

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Naoto Tanaka 1-10-10 Nishigaoka, Uozumi-cho, Akashi-shi, Hyogo Prefecture (Reference) 4D017 AA01 BA11 BA12 CA03 CB05 DA02 DB04 EA01 EB03 EB06 4D061 DA04 DA08 DB13 DB18 EA02 EB05 EB18 EB19 EB23 EB29 EB37 GA12 GA14 GA21 GC15

Claims (5)

[Claims] An undiluted solution (L) containing an ionic substance is converted into a purified liquid (L ₁ ) having a reduced ratio of an ionic substance by using a purification apparatus provided with a flow-through type electric double layer capacitor ( ₁ ). In separating into high-concentration liquid (L ₂ ) in which the ratio of ionic substances is increased, three or more capacitors (1) are used, and adsorption of ionic substances by charging, short-circuit or reverse charging The desorption of ionic substances adsorbed by the
In a predetermined pattern while interlocking with the connection between and the switching between introduction and derivation of the liquid to each condenser (1), whereby the stock solution (L) is continuously processed at a predetermined flow rate, Purified liquid (L ₁ ) and high concentration liquid (L ₂ ) of specified quality
Wherein the liquid is continuously taken out at a predetermined flow rate. 2. Three operations of A, B, and C are used as the condenser (1), and a six-stage operation of “adsorption 1 → adsorption 1 → desorption 1 → desorption 2 → adsorption 2 → adsorption 2” is performed by A , B, and C,
2. The purification method according to claim 1, wherein the steps are performed while being shifted by two stages in this order. 3. A three-stage operation of “adsorption 1 → adsorption 2 → desorption” is performed by using three units of A, B and C as the condenser (1).
2. The method according to claim 1, wherein the steps B and C are carried out while being shifted one by one in this order. 4. Capacitors (1) of A, B, C, D
Using a group, the four-stage operation of “adsorption 1 → adsorption 2 → desorption 1 → desorption 2” is performed for each of A, B, C, and D while shifting one stage in this order. The purification method according to claim 1, wherein 5. A liquid-permeable electric double layer capacitor (1) comprising a conductive support layer (11), a high surface area conductive layer (12) and a non-conductive porous spacer layer (13). Item 4. The purification method according to Item 1.