TW201350440A - Sewage treatment apparatus by electrodialysis and treatment method thereof - Google Patents

Abstract

The present invention provides a sewage treatment apparatus by electrodialysis, including: positive/negative electrodes; a plurality of diaphragms separately disposed between the positive/negative electrodes for dividing the space between the positive/negative electrodes into one first zone and two second zones; and a first conductor disposed inside the first zone. In consideration of the defects of traditional electrodialysis and the problems of higher costs of a negative/positive ion exchange membrane, this invention provides the first conductor disposed inside the first zone, so that the average electric resistivity of the first zone is lower than that of the second zone. A voltage difference produced during the introduction of an electric current can make the negative/positive ions in the first zone move toward the second zone, thereby achieving the purpose of separation. By said way, the present invention can greatly lower the cost and electric energy required in traditional electrolysis and is used for seawater desalination.

Description

Electrodialysis sewage treatment device and treatment method thereof

The invention relates to an electrodialysis sewage treatment device and a method thereof, in particular to an electrodialysis sewage treatment device and a method thereof for producing a difference in electrical resistivity between different regions by using a conductor.

Electrodialysis (ED) is a series of interdigitated anion/cation exchange membranes interlaced together. The electrolyte solution can flow between the exchange membranes. When DC voltage is applied to both sides, the cation can only penetrate. The cation exchange membrane and the anion can only penetrate the anion exchange membrane", so that the cation in the water can only pass through the cation exchange membrane and cannot pass through the anion membrane, and the anion in the water can only pass through the anion exchange membrane and cannot pass through the cation exchange membrane. The solution of low electrolyte concentration (ie, fresh water) and the solution of high electrolyte concentration (ie, seawater) are separated to achieve the purpose of sewage treatment.

Electrodialysis is a type of Membrane process that was previously applied to the demineralization of Brackish water to make drinking water. The commercial electrodialysis process began in the 1960s, and the Electrodialysis Reversal (EDR) has greatly improved the problem of fouling and has become the mainstream technology of electrodialysis. In the 1980s, EDR was able to effectively solve various problems due to the use of the Aliphatic anion membrane, such as suspended matter, organic matter, and mineral-containing emissions.

Due to the high total dissolved solids (TDS) contained in seawater, if the electrodialysis method is used to desalinate seawater, the electricity consumption per ton of seawater is higher than the RO method, which is not in line with economic benefits, making electricity Dialysis It can only be applied to the salt water desalination work with low TDS.

The traditional formula for calculating the actual efficiency of electrodialysis is as follows: Wherein, ζ represents the actual utilization efficiency; z represents the ion charge number; F represents the Faraday constant, 96485 Amp-s/mol; Q _f represents the desalted water flow rate, unit: L/s; Represents the concentration of demineralized water at the inlet, unit: mol/L; Represents the concentration of outlet desalinated water, unit: mol/L; N represents the logarithm of the anion/cation exchange membrane; I represents the current; that is, the actual efficiency of electrodialysis = the amount of salt ion excluded / the logarithm of the anion/cation exchange membrane X input current).

At present, the understanding of electrodialysis is considered to be unreasonable when an anion encounters a cation exchange membrane or a cation encounters an anion exchange membrane. Because the back of the anion/cation is still affected by the repulsive force of the isotropic electrode and the attraction of the front opposite electrode, the cation/cation cannot be rebounded, and at most it stays in place. Accordingly, the foregoing phenomenon is in accordance with the electric field formula, that is, the potential difference between the positive electrode and the negative electrode inevitably causes a flow between the anode/cation. Although the arrangement of the anion/cation is inconsistent with the electrical properties of the ion exchange membrane itself, since the positive electrode and the negative electrode continue to supply current, the electrical properties of the anion/cation exchange membrane itself can be offset.

In other words, the traditional anion/cation exchange membrane selectively allows ions to pass through The law is not reasonable. The negative departure field moves from the negative electrode to the positive electrode. Since the negative electric field is transmitted by the negative ions, if the anion cannot pass through the anion exchange membrane, how should the negative electric field continue to be transmitted to the positive electrode. For the same reason, the positive electric field is also the same. If so, the entire system becomes an insulated system, and the aforementioned formula for calculating the actual efficiency cannot explain this phenomenon at all when the current cannot pass. Therefore, it is clear that the current concept of the traditional electrodialysis principle is not correct.

In order to explore the true principle of electrodialysis, it is necessary to understand that the anion/cation exchange membrane is a kind of polar resin with considerable conductivity and many pores, which can allow the passage of anion/cation, which is a kind of yin/positive Porous insulation layer.

When the cations in the solution are sucked away by the negative electrode, the released negative ions are attracted to each other by the principle that Coulomb's law attracts each other. Because the ion exchange membrane is electrically charged, according to Coulomb's law, the principle of homosexual reciprocal attraction attracts positive ions to reduce the speed of slowing down due to the repulsion, while the anion accelerates the speed of advancement due to the attraction of the opposite sex.

Thus, the anion/cation will be electrically neutralized at the pores of the anion/cation exchange membrane. Since the velocity of the cation is relatively small, it will be pushed back by the anion, and the negative ion on the back side will inherit the energy of the original anion and continue to move backwards, just like the Newtonian pendulum.

Accordingly, the foregoing process is repeated in the solution until one of the anions is pushed out of the ion membrane, causing an anion to move forward, and the kinetic energy of the cation is stopped by the anion.

In the case of an anion exchange membrane, since the electrical property is negative, the foregoing situation is reversed, and the cation moves forward, while the kinetic energy of the anion is It is stopped by the cation and stays still.

Since the voltage difference applied by the outside is inevitably higher than the voltage difference between the ionic membranes, the electrical properties of the ion exchange membrane itself are not sufficient to completely block the isotropic ions from advancing. However, the electrical properties of the ion exchange membrane itself still cause different resistance to different electrical ions, and the difference in speed (also referred to as energy difference) caused by these resistance differences is that the dominant anion/cation finally gathers differently. The reason for the area.

When an ion exchange membrane is contained in a separation tank, one ion can be allowed to pass; when a separation tank contains two ion exchange membranes, two different ions can be allowed to move to different regions, respectively. In addition, how much current is input is equivalent to inputting the same amount of positive and negative ions simultaneously. Therefore, with several ion exchange membranes, it is possible to separate several different ion currents, and the negative/cation flow divided by two is equal to the current. Accordingly, the above calculation of the actual efficiency of the electrodialysis method can be rationalized by N×I. Explanation.

Therefore, it can be determined that the difference in resistance caused by the anion/cation exchange membrane to different electrochemical ions causes the flow velocity of the anion/cation flow to be different, and the pressure difference generated thereby separates the ions into different regions. effect. Since the ion current is equal to the current, in other words, the difference in the resistance of the ion current is actually the difference in resistance; for the same reason, the voltage difference of the ion current is actually the voltage difference. That is to say, the electrodialysis method utilizes the electrical properties of the anion/cation exchange membrane itself, resulting in a membrane having different resistance values for the anion/cation, which is a so-called variable resistor, thereby generating a resistance difference, thereby causing a voltage. Poor, and achieve the purpose of ion separation.

Furthermore, since V=IR, when a current is applied, a difference in resistance generates a voltage difference, and the current generated by the voltage difference is an ion. The source of power that separates each other.

Since the ions themselves have mass, the electromotive force is originally a kind of force, so the above situation can be explained by the law of inertia, so the electric resistance difference inevitably generates an electromotive force, and the ions are concentrated to a predetermined region.

In addition, the above theory can also be verified by the salt rejection rate. The desalination rate is theoretically the amount of salt that can be converted by how much current is input. However, the conventional electrodialysis method can only achieve a desalination rate of about 80%, and the inverted electrodialysis method can be increased to 90%. When the electrodialysis reaches a certain level, no matter how much current is input, the desalting work cannot be continued. This phenomenon is traditionally explained by the disturbance of the water flow or the reverse osmotic pressure between the concentration differences.

However, the osmotic pressure does not have this situation. The osmotic pressure is proportional to the concentration difference / the distance between two points. It has a linear relationship. When the curve of the change is the curtain curve, a certain factor causes the current to pass to a certain extent, causing the principle of ion separation. It completely loses its effect, so no matter how it flows, it doesn't work. However, if it is explained by the difference in resistance, it is completely reasonable. When the water in one zone is diluted, the average resistivity increases; on the other side, the average resistivity decreases as the concentration increases.

When the difference in resistance between the two regions reaches a certain level, the difference in resistance generated by the anion/cation exchange film cancels each other out. When the resistance difference between the two is canceled, no voltage difference can be generated regardless of the input current. Naturally, it is impossible to cause differential flow of ion currents, thereby losing the effect of separation. Therefore, it can be ascertained that the true principle of electrodialysis is to use the difference in electrical resistance to achieve the purpose of separation, rather than an anion/cation exchange membrane.

Accordingly, the main object of the present invention is to provide a different from the prior art. The electrodialysis sewage treatment device and the treatment method thereof can greatly improve the separation effect of the acoustic electrodialysis. Since the invention does not need to use any expensive anion/cation exchange membrane, the electrodialysis membrane can be applied to desalinated seawater and provide A more economical sewage treatment device and method.

In order to achieve the foregoing objective, the present invention provides an electrodialysis sewage treatment apparatus comprising: an electrode group including a positive electrode and a negative electrode, wherein the positive electrode and the negative electrode system are respectively disposed on the electrodialysis sewage treatment device Corresponding sides; at least two separation films are disposed between the positive electrode and the negative electrode, so that the positive electrode and the negative electrode are separated into a first region and two second regions The first region is formed between the second regions; a sewage inlet is connected to the first region and the second regions; a first conductor is disposed at the first region a fresh water outlet connected to the first region; a concentrated water outlet connected to the second region; and a power supply connected to the positive electrode of the electrode group and negative The electrodes are connected to form an electrical circuit.

Preferably, the electrodialysis sewage treatment device further comprises two second conductors respectively disposed in the second regions, and the volume of the second conductors is respectively smaller than the volume of the first conductor.

Preferably, the first conductors and the second conductors may be stainless steel; or the first conductors and the second conductors may be an iron mesh. More preferably, the iron mesh is disposed in a folded shape in the first region or the second region.

Preferably, the electrodialysis sewage treatment device further comprises at least one partition adjacent to the at least two separation membranes.

In the present specification, the separation membrane is a substance that allows the anion/cation to shuttle back and forth; the separator is made of a water-impermeable material.

Preferably, the at least one partition is formed with a plurality of holes, and the first conductor and the second conductive systems are disposed adjacent to the holes.

Preferably, the at least two separator films may have a thickness of less than 1 mm.

Preferably, the electrodialysis sewage treatment device further comprises a power supply, the power supply is connected to the positive electrode and the negative electrode to form an electrical circuit, so that the first region of the electrodialysis sewage treatment device is The average resistivity is less than the average resistivity of the second regions.

In order to achieve the foregoing object, the present invention further provides an electrodialysis sewage treatment apparatus comprising the steps of: providing an electrodialysis sewage treatment device as described above; and treating a sewage to be treated from the electrodialysis sewage treatment device a sewage inlet is introduced; a current is supplied from the power supply, so that an average resistivity of the first region of the electrodialysis sewage treatment device is smaller than an average electrical resistivity of the second regions; and the sewage to be treated The cation and anion systems are respectively moved from the first region to the negative electrode and the positive electrode, whereby a fresh water is collected from the fresh water outlet, and a concentrated water is collected from the concentrated water outlet.

Preferably, the positive electrode and the negative electrode of the electrode group of the electrodialysis sewage treatment device of the present invention can also be mutually exchanged to design an inverted-electrode dialysis device. Thereby improving the efficiency of sewage treatment.

In summary, the present invention can simultaneously generate a resistivity difference between the first region and the adjacent two second regions by providing a first conductor in the first region, so that the cation and the anion in the sewage are respectively Moving from the first region to the negative electrode and the positive electrode, the cation and the anion are simultaneously concentrated in the second region, thereby achieving the separation work.

Accordingly, the electrodialysis treatment apparatus and method of the present invention can collect a fresh water at the fresh water outlet by the difference in electrical resistivity between the first region and the second region without using an expensive dialysis membrane. And collect a concentrated water from the concentrated water outlet to complete the sewage treatment work.

Hereinafter, embodiments of the electrodialysis treatment apparatus and method of the present invention will be described by way of specific embodiments, and those skilled in the art can easily understand the advantages and effects of the present invention through the contents of the present specification, and Various modifications and changes are made in the spirit of the invention to practice or apply the invention.

The electrodialysis sewage treatment device of the invention comprises an electrode group, a plurality of separator membranes, a sewage inlet, a plurality of first conductors, a plurality of second conductors, a fresh water outlet and a concentrated water outlet.

Please refer to FIG. 1A and FIG. 1B together, which is an embodiment of the electrodialysis sewage treatment device of the present invention. The electrode group includes a positive electrode 111 and a negative electrode 112. The positive electrode 111 and the negative electrode 112 are respectively disposed on opposite sides of the electrodialysis sewage treatment device 1 .

The plurality of separation films 121 are spaced apart between the positive electrode 111 and the negative electrode 112, thereby causing a region between the positive electrode 111 and the negative electrode 112. The partition is a plurality of first regions R1 and a plurality of second regions R2. The first region R1 and the second regions R2 are spaced apart from each other, and the first region R1 is formed between the second regions R2. In this embodiment, the positive electrode 111 and the negative electrode 112 are adjacent to the second region R2.

Further, a spacer 122 is further disposed adjacent to the spacer film 121, and the spacer 122 has a plurality of holes 123, and the first conductors 14 and the second conductors 15 are respectively disposed corresponding to the holes. Next to 123.

Herein, the separator can further improve the separation efficiency of the positive anion, but the present invention can also use the electrodialysis sewage treatment device without a separator to complete the sewage treatment work.

The sewage inlet 13 is connected to the first region R1 and the second region R2 for introducing a sewage into the first region R1 and the second of the electrodialysis sewage treatment device of the present invention. In the region R2, the subsequent electrodialysis sewage treatment work is performed. Here, the sewage entering the first region R1 and the second region R2 may be seawater.

In this embodiment, a plurality of first conductors 14 are disposed in the first region R1, and a plurality of second conductors 15 are disposed in the second region R2, and the volume of the second conductor 15 is smaller than that of the first conductor 14 volume.

The first regions R1 are respectively provided with an output port connected to a fresh water outlet 16 for collecting the treated fresh water; and the second regions R2 are also respectively provided with an output port, which is coupled with a concentrated water. The outlet 17 is connected to collect the treated concentrated water.

Hereinafter, the process of the electrodialysis wastewater treatment method using the electrodialysis sewage treatment apparatus of the present invention will be described in detail by taking the seawater treatment as an example by using FIG. 1A, FIG. 1B and FIG.

As shown in Figure 2, the collected seawater may be subjected to the desired pretreatment steps, such as coagulation, sedimentation, sand filtration, etc., as appropriate. Thereafter, the pretreated seawater is passed to a storage tank for storage.

Next, the impurities in the pretreated seawater are further filtered to obtain a seawater to be treated, and the seawater to be treated is introduced into the sewage inlet 13 of Fig. 1A.

Then, a current is supplied to a DC power supply connected to the positive electrode 111 and the negative electrode 112. Since the first conductor 14 and the second conductor 15 are respectively disposed in the first region R1 and the second region R2, The average resistivity of the first region R1 is smaller than the average resistivity of the second regions R2. When the current is passed, a voltage difference can be generated, so that the cations and anions of the seawater in the first region R1 are respectively received by the negative electrode 112 and the positive electrode 112. The attraction of the electrode 111 is concentrated in a large amount toward the adjacent second region R2 to achieve the purpose of ion separation.

Thereby, the sewage treatment is performed by using the electrodialysis sewage treatment device of the present invention, and the resistivity difference generated between the first region R1 and the second region R2 can be obtained without using an expensive anion/cation exchange membrane, that is, A fresh water can be collected from the fresh water outlet 16 connected to the first region R1, and a concentrated water is collected from the concentrated water outlet 17 connected to the second region R2 to complete the electrodialysis sewage treatment work of the present invention. Here, the collected concentrated water is rich in a large amount of sodium ions (Na ⁺ ), calcium ions (Ca ²⁺ ), chloride ions (Cl ⁻ ), sulfate ions (SO ₄ ^2- ), and CO ²⁻ .

Please refer to FIG. 1B in particular to further illustrate the process of the sewage treatment of the present invention. In this embodiment, a plurality of rows of the first conductor 14 and the second conductor 15 are disposed beside the plurality of holes 123 of the spacer 122.

When the DC power supply is connected to the positive power and the 111 and the negative electrode 112 When a current is applied, a voltage difference is also generated when a difference in resistance occurs between the first region R1 and the second region R2. At this time, the ion current starts from a region having a lower average resistivity (ie, the first region R1). ) to a region where the average resistivity is high (ie, the second region R2).

According to the resistance formula: resistance = resistivity × resistance length / cross-sectional area. When the cross-sectional area is smaller, the resistance is larger. In other words, in the electrodialysis sewage treatment apparatus of the present invention, the first conductor and the second conductor are respectively disposed in the holes of the separator, and a plurality of parallel resistors are disposed in the second region of the first region.

The resistance values in parallel are the sum of the derivatives of the resistors. Assuming that the resistance values of other regions outside the first conductor are infinite, the total resistance R = 1 / R1 + 1 / infinity = 1 / R1 + 0 = 1 / R1. In other words, the maximum value of the resistance in the first region is at most only the parallel sum of the resistance values of all the first conductors, which is smaller than the resistance value of the second region. Even if the resistance value of the reverse osmosis membrane affects, the hole opening in the second region increases the resistance, so the resistance difference between the two reverse osmosis membranes can cancel each other out.

Therefore, when a current is applied, the difference in resistance between the first region and the second region causes a voltage difference, so that the anion/cation in the first region continuously moves toward the second region, resulting in a separation effect.

When 304 stainless steel is used as the first conductor and the second conductor, it is assumed that the size of 304 stainless steel is 1 mm thick, 1 meter long, 20 cm wide, and its electrical resistivity is about 0.73 ohms per square millimeter per millimeter. The total resistance of a conductor is only about 0.00365 ohms. When there are N conductors, the total resistance value can be obtained by dividing by the number of N.

Therefore, basically, it can be assumed that the resistance value of the first region (low resistance region) approaches zero. How much resistance does the second area (high resistance area) have? The portion of the second conductor is considered to be zero, and only the resistance value of the solution region is calculated, that is, the difference in resistance between the first region and the second region.

In the present embodiment, taking seawater as an example, the electrical resistivity of seawater is 25 ohm cm/cm ² , that is, the electrical resistivity per cm of seawater per one-sectional area of 1 cm ² is 25 ohms.

Accordingly, the difference in electric resistance between seawater and 304 stainless steel is (25/0.73) × (100 cm / 1 m) / (1 cm ² / 100 mm ² ) = 342465 times. It can be seen from this that the difference in electrical resistance between seawater and 304 stainless steel is large. Therefore, the first conductor is used to generate a difference in resistance, and the reduced resistance value (or energy loss) is at least 90% or more of the conventional electrodialysis method.

When the current is passed, a voltage difference is generated, and the difference in resistance produces a voltage difference that separates the ions. This voltage difference generates a voltage at a position where the resistance difference is generated by the same amount of current as the input current, and the ion current is forced out of the resistor. Area.

When a concentration difference occurs between two different regions, according to the law of diffusion, the salt molecules will flow back from the high resistance region to the low resistance region, as shown in Fig. 1A, and the pressure difference is sufficient to force the ions to cross the layer. The separator, this separation membrane blocks the ion reflux and completely achieves the ion separation effect.

In the present invention, the material of the separation film may be any film having small pores such as cloth, small sieve or the like. Since the separation film itself generates a small resistance value, it is necessary to control the thickness of the film to be less than 1 mm so as not to increase the resistance value of the excessive first region and reduce the difference in electrical resistance between the first region and the second region. .

Furthermore, in order to improve the efficiency of sewage treatment, the electrode group must be switched over a period of time, that is, the inverted pole design, so that the ion current exchange can be smoother.

Please refer to FIG. 3, which is another embodiment of the electrodialysis sewage treatment apparatus of the present invention. To further describe in detail the direction of movement of the positive anions in the sewage treatment, Figure 3 omits the sewage inlet, fresh water outlet and concentrated water outlet of the electrodialysis unit.

Please refer to FIG. 3, the positive electrode 311 and a negative electrode 312. The positive electrode 311 and the negative electrode 312 are also respectively disposed on opposite sides of the electrodialysis sewage treatment device 3 .

In this embodiment, the electrodialysis sewage treatment device includes two separation membranes 321 disposed between the positive electrode 311 and the negative electrode 312, so that the positive electrode 311 and the negative electrode 312 are separated from each other. The first region R1 and the plurality of second regions R2 are plural. The first region R1 is formed between the second regions R2, and the second regions R2 are adjacent to the positive electrode 311 and the negative electrode 312.

In this embodiment, the first conductor 34 is disposed in the first region R1, and the second region R2 is not provided with other conductors. Accordingly, when a current is introduced, since the first conductor is affected by the positive electrode 311 and the negative electrode 312, the average resistivity of the first region R1 is smaller than the average resistivity of the second region R2.

Accordingly, the ion dissociation speed existing in the first region R1 (ie, the low resistance region) is faster, and the ion dissociation velocity in the second second region R2 (ie, the high resistance region) is slower due to different ion dissociation speeds. A pressure difference is generated between the first region R1 and the second region R2, thereby generating a flow of the ion current, so that the cation and the anion move to the negative electrode 312 and the positive electrode 311, respectively, to achieve the separation effect.

Further, since the first guiding system is disposed in the first area, The average resistivity in the first region is less than the average resistivity of the second region R2. When a current is applied, if the current (I) is fixed, the voltage of the first region is also smaller than the voltage of the second region. According to the electric energy formula: power (W) = voltage (V) × current (I), the electric energy of the first region is also smaller than the electric energy of the second region.

Therefore, when the current passes through the sewage to be treated, since the energy is transmitted by the ion flow, according to the energy immortality and the energy conservation rate, the second region of high energy must continuously obtain the positive anion, otherwise the higher energy cannot be maintained; The first region of low energy must not continuously lose positive anions, otherwise it will not be able to maintain lower energy. In other words, the positive anion present in the first region is constantly moved to the second region by the difference in electrical resistance between the first region and the second region for the purpose of sewage treatment.

Accordingly, the present invention only needs to pass current, use the first conductor and the separation membrane, and the water-permeable separation membrane can ensure the smooth operation of the sewage treatment as long as the pressure difference of the osmotic pressure can be offset.

By minimizing the range of electrical resistance differences, the electrical dialysis treatment method of the present invention requires less electrical energy, and the electrical resistance difference only needs to be large enough to allow ions to flow through the separation membrane. Therefore, the use of the electrodialysis sewage treatment device of the present invention for sewage treatment can greatly reduce the cost and power consumption, making the electrodialysis method more economical.

In the actual efficiency of electrodialysis, the resistance difference of the traditional electrodialysis method is created by the ion current, and the water quality can only be treated to the water quality of 100,000 ohm meters. When the higher the water quality, the greater the resistance, the more difficult it is to handle. .

In contrast, the electrical resistance difference of the electrodialysis wastewater treatment method of the present invention is created by the difference in electrical resistance between the first conductor and the ionic solution. As described above, even if the resistance of the ionic solution is infinite, the present invention can be handled smoothly. And no need to spend too much power.

Please refer to FIG. 4, which is another embodiment of the electrodialysis sewage treatment apparatus of the present invention. As described in the foregoing embodiment, the electrodialysis sewage treatment apparatus 4 of the present embodiment also includes the positive electrode 411, the negative electrode 412, the plurality of separation membranes 421, the sewage inlet 43, the fresh water outlet 46, and the concentrated water outlet 47 as described above. .

The difference is that the electrodialysis sewage treatment device 4 of the embodiment can complete the sewage treatment work without additionally providing a partition plate. In addition, the first conductor 44 and the second conductor 44 disposed in the first region R1 and the second region R2 are folded iron meshes that allow current and water to flow therethrough.

Accordingly, the provision of a folded iron mesh in the first region and the second region allows the current not to be used as a conductor of the ion solution, which is sufficient to save at least 90% of the electrical energy loss by the conventional electrodialysis method.

In summary, the present invention utilizes the difference in electrical resistance between the first conductor and the ionic solution. When a current is applied, the voltage difference forces the ion current out of the first region, thereby achieving the effect of ion separation. The electrodialysis sewage treatment method of the invention can be applied not only to seawater desalination, but also to the effect of sewage treatment. It can process a large amount of wastewater containing only trace amounts of pollutants at a very low cost, and has a strong sewage treatment effect, and can even be applied to the treatment of nuclear waste water. Accordingly, the present invention can effectively enhance the application field and separation effect of the conventional electrodialysis method. Since the invention does not require the use of an expensive anion/cation exchange membrane, the cost and electric energy required for sewage treatment can be greatly reduced, thereby further improving electrodialysis. The application value of sewage treatment methods.

1‧‧‧Electric dialysis sewage treatment plant

111‧‧‧ positive electrode

112‧‧‧Negative electrode

121‧‧‧Separate film

122‧‧‧Baffle

123‧‧‧ hole

13‧‧‧Sewage entrance

14‧‧‧First conductor

15‧‧‧Second conductor

16‧‧‧ Freshwater exports

17‧‧‧Concent water outlet

R1‧‧‧ first area

R2‧‧‧ second area

311‧‧‧ positive electrode

312‧‧‧negative electrode

321‧‧‧Separate film

322‧‧‧Baffle

323‧‧‧ holes

34‧‧‧First conductor

4‧‧‧Electric dialysis sewage treatment plant

411‧‧‧ positive electrode

412‧‧‧negative electrode

43‧‧‧Sewage entrance

44‧‧‧First conductor

45‧‧‧second conductor

46‧‧‧ Freshwater exports

47‧‧‧Concent water outlet

1A is an electrodialysis sewage treatment apparatus according to an embodiment of the present invention. schematic diagram.

1B is a schematic view showing the detailed structure of an electrodialysis sewage treatment apparatus according to an embodiment of the present invention.

2 is a flow chart of the electrodialysis wastewater treatment method of the present invention.

3 is a schematic view showing the detailed structure of an electrodialysis sewage treatment apparatus according to another embodiment of the present invention.

4 is a schematic view of an electrodialysis sewage treatment apparatus according to still another embodiment of the present invention.

1‧‧‧Electric dialysis sewage treatment plant

111‧‧‧ positive electrode

112‧‧‧Negative electrode

121‧‧‧Separate film

122‧‧‧Baffle

123‧‧‧ hole

13‧‧‧Sewage entrance

14‧‧‧First conductor

15‧‧‧Second conductor

16‧‧‧ Freshwater exports

17‧‧‧Concent water outlet

R1‧‧‧ first area

R2‧‧‧ second area

Claims (10)

An electrodialysis sewage treatment device comprising: an electrode group comprising a positive electrode and a negative electrode, wherein the positive electrode and the negative electrode are respectively disposed on opposite sides of the electrodialysis sewage treatment device; Two spacer films are disposed between the positive electrode and the negative electrode, so that the positive electrode and the negative electrode are separated into a first region and two second regions, wherein the first region is formed Between the second regions; a sewage inlet connected to the first region and the second regions; a first conductor disposed in the first region; a fresh water outlet; Connected to the first region; a concentrated water outlet connected to the second regions; and a power supply connected to the positive electrode and the negative electrode of the electrode group to form an electricity Sexual loop. The electrodialysis sewage treatment device of claim 1, wherein the electrodialysis sewage treatment device further comprises two second conductors respectively disposed in the second regions, and the volume lines of the second conductors are respectively smaller than The volume of the first conductor. The electrodialysis sewage treatment device of claim 2, wherein the electrodialysis sewage treatment device further comprises at least one separator adjacent to the at least two separation membranes. The electrodialysis sewage treatment device of claim 3, wherein the at least one partition is formed with a plurality of holes, and the first conductor and the second conductive systems are disposed adjacent to the holes. The electrodialysis sewage treatment apparatus of claim 1, wherein the first guiding system is stainless steel. The electrodialysis sewage treatment device of claim 1, wherein the first guiding system is an iron mesh. The electrodialysis sewage treatment apparatus of claim 2, wherein the second conductivity system is stainless steel. The electrodialysis sewage treatment device of claim 2, wherein the second guiding system is an iron mesh. An electrodialysis sewage treatment method comprising the steps of: providing an electrodialysis sewage treatment device according to any one of claims 1 to 8; and smearing a sewage to be treated by the electrolysis sewage treatment device a water inlet is introduced; a current is supplied from the power supply, whereby an average resistivity of the first region of the electrodialysis sewage treatment device is less than an average electrical resistivity of the second regions; and the sewage to be treated The cation and anion systems are respectively moved from the first region to the negative electrode and the positive electrode, whereby a fresh water is collected from the fresh water outlet, and a concentrated water is collected from the concentrated water outlet. The electrodialysis sewage treatment method according to claim 9, wherein the positive electrode and the negative electrode of the electrode group of the electrodialysis sewage treatment device are mutually replaceable.