CN107176728B - Device for treating sewage by electrochemical oxidation method and method for treating sewage by using device - Google Patents

Abstract

The invention discloses a sewage treatment device by an electrochemical oxidation method, which comprises a power supply device, at least two electrolytic cells and a purification cell; wherein: the electrolytic cell includes a flowing electrolytic cell and a fixed electrolytic cell, which are alternately arranged; The anode plate and the cathode plate are respectively set, and the particle electrode is filled in the electrolytic cell; the positive electrode of the power supply device is connected with the anode plate in the electrolytic cell by a wire, and the negative electrode of the power supply device and the cathode plate in the electrolytic cell are connected by a wire; between the electrolytic cells, the electrolytic cell and the purification cell The pools are connected through overflow walls; the upper part of the first flow electrolytic cell is provided with a water inlet, and the lower part of the purification pool is provided with a water outlet. The invention also discloses a method using the above device, namely: pretreatment-adjustment device-water injection treatment-collection. Using the electrochemical oxidation method for treating sewage in the sewage treatment device of the present invention greatly improves the sewage treatment efficiency and simultaneously increases the sewage treatment capacity; the sewage can be treated more thoroughly and the treatment effect is better.

Description

A device for treating sewage by an electrochemical oxidation method and a method for treating sewage with the same

technical field

The invention belongs to the technical field of sewage treatment devices and methods, and in particular relates to a sewage treatment device by an electrochemical oxidation method and a method for treating sewage with the same.

Background technique

Since human beings entered the industrial society, water pollution has become increasingly serious. Due to different production processes, raw materials and products, various types of industrial wastewater have different compositions and properties. Among the organic pollutants discharged by the industrial industry, benzene and phenols are the main ones. Such substances will cause toxicity and inhibition to the microorganisms treated by biochemical treatment, and are not easily degraded by microorganisms. Electrochemical oxidation technology uses the catalytic activity of electrode materials to directly anodic oxidation degradation of refractory organic pollutants in water, or to oxidize organic matter through strong oxidizing free radicals (such as OH) generated during electrolysis. degradation. The addition of three-dimensional particle electrodes can improve the water treatment effect.

SUMMARY OF THE INVENTION

One of the objectives of the present invention is to provide a sewage treatment device by electrochemical oxidation that can improve the effect of water treatment.

For achieving the above object, the technical scheme of the present invention is:

A device for treating sewage by an electrochemical oxidation method, comprising a power supply device, at least two electrolytic cells and a purification cell; wherein: the electrolytic cell includes a flow-type electrolytic cell and a fixed-type electrolytic cell, which are alternately arranged; anodes are respectively arranged on the two side walls of the electrolytic cell Plate and cathode plate, the electrolytic cell is filled with particle electrodes; the flow electrolytic cell is provided with a stirring rod, and the stirring rod is made according to the ratio of iron: nickel: manganese mass ratio of 2-4:1-3:1-3; power supply The positive electrode of the device is connected to the anode plate in the electrolytic cell by wires, and the negative electrode of the power supply device is connected to the cathode plate in the electrolytic cell by wires; The upper part of the electrolytic cell is provided with a water inlet, and the lower part of the purification tank is provided with a water outlet.

Further, the particle electrode filled in the flow electrolytic cell is cylindrical, and has a length of 1-3 mm and a diameter of 2-4 mm; the density of the particle electrode filled in water is 400-500 mg/l.

Further, the particle electrodes are iron particle electrodes, nickel particle electrodes and manganese particle electrodes.

Further, the particle electrode filled in the stationary electrolytic cell is an activated carbon electrode, and the activated carbon electrode is an activated carbon electrode with a porous structure; wherein: the diameter of the activated carbon electrode is 5-15 mm, and the pore diameter of the activated carbon electrode is 20-30 μm; The filling height of the electrolytic cell is lower than the height of the overflow wall.

Further, the anode plate is Ti/PbO ₂ -La electrode, and the cathode plate is nickel foam; the distance between the anode plate and the cathode plate is 75-80mm, and the area of the anode plate and the cathode plate is 56-64cm ² .

Furthermore, the purification tank is filled with a matrix material layer, and the matrix material layer includes zeolite and crushed stone, which are alternately arranged.

Further, the height of the overflow wall is lower than the height of the walls of the electrolytic cell and the purification cell.

Compared with the prior art, the advantages of the present invention are:

1. In the present invention, at least two electrolytic cells are arranged, and they are alternately arranged according to the flow type and the fixed type. Compared with a single electrolytic cell, the present invention has the advantages of clean and thorough treatment of sewage. In the present invention, the sewage is first treated by the flowing electrolytic cell. The flowing electrolytic cell can perform large batch processing on the sewage, which is better than the fixed electrolytic cell. In addition, the stirring rod can accelerate the treatment Quickly reduce the pollution degree of sewage. Then the sewage treated by the flow electrolytic cell flows into the fixed electrolytic cell, and the fixed electrolytic cell can further adsorb and treat the sewage, which can further purify the sewage. If the fixed electrolytic cell is used first, and then the flow electrolytic cell is used to treat sewage, the reaction time will be slow, and it will be easy to block, and the sewage treatment effect is very insignificant.

2. The present invention adopts the electrochemical oxidation method to treat sewage, and uses a three-dimensional particle electrolytic cell. The cathode plate and the anode plate in the electrolysis cell generate hydroxyl radicals (·OH) during the electrolysis process, which degrades the dissolved organic matter in the sewage. At the same time, the three-dimensional particle electrode has the functions of adsorption and micro-electrode, and can adsorb substances with strong oxidizing property. The organic matter in the sewage undergoes oxidation or reduction reaction on the surface of the particle electrode, and a large number of micro-electrolysis cells formed between the particle electrodes can produce Hydroxyl radicals (·OH) with strong oxidizing properties can decompose organic matter and improve the effect of water treatment. Since the stirring rod in the flow electrolytic cell of the present invention is an alloy made of iron, nickel, and manganese according to a certain mass ratio, when the stirring rod is stirred, an oxidation or reduction reaction also occurs on the surface of the stirring rod, accelerating the Degradation of organic matter in solution. The three-dimensional particle electrodes in the flow electrolytic cell are iron particle electrodes, nickel particle electrodes and manganese particle electrodes, which avoids the formation of short-circuit current between the solutions by excessive conductive particles, which reduces the reaction current and ultimately reduces the efficiency of organic matter treatment.

3. In order to improve the efficiency of sewage treatment, the conductivity in the solution needs to be increased, and the conductive material needs to choose a material with better conductivity; at the same time, the cost of the conductive material must be considered. In order to meet the above conditions, the present invention selects iron, nickel and manganese as particle electrodes in the flow electrolytic cell, and the stirring rod is made of an alloy prepared from these three metals.

4. The particle electrode in the stationary electrolytic cell of the present invention selects the activated carbon electrode, which can further adsorb the sewage treated by the flowing electrolytic cell to increase the treatment effect. The electrolytic cell is followed by a purification tank, which can filter the treated sewage again, making the sewage treatment cleaner and more thorough.

5. The present invention ensures the continuity and completeness of sewage treatment, simultaneously improves the efficiency of sewage treatment, and greatly increases the amount of sewage treatment.

The second object of the present invention is to provide a method for treating sewage, that is, a method for treating sewage using the electrochemical oxidation method for treating sewage provided by the one object of the present invention.

For achieving the above object, the technical scheme of the present invention is:

A method for treating sewage, using the electrochemical oxidation method provided in one of the objects of the present invention to treat sewage, comprising the following steps:

(1) Before the sewage to be treated enters the sewage treatment device, the sewage needs to be pretreated, that is, a flocculant is added to the sewage to be treated to precipitate impurities in the sewage;

(2) The sewage treatment device is placed horizontally, and the mobile electrolytic cell and the fixed electrolytic cell are alternately arranged; the power supply device and the stirring rod are turned on, and the power supply voltage of the power supply device is adjusted;

(3) enter the sewage pretreated in step 1 into the flow electrolytic cell from the water inlet, and flow into the stationary electrolytic cell through the overflow wall; make the pretreated sewage pass through the overflow after being processed by at least two electrolytic cells The wall flows into the purification tank for purification treatment; control the water flow velocity of the water inlet and the water outlet to be equal;

(4) Collect the treated water flowing out from the water outlet.

Further, the power supply voltage of the power supply device is 5-9V, and the current density between the anode plate and the cathode plate is 2-8mA/cm ² ; the electrification time of each electrolytic cell is 90-120min; The water flow rate is 15-23ml/s.

Compared with the prior art, the advantages of the present invention are:

The method for treating sewage by using the electrochemical oxidation treatment device provided in one of the objects of the present invention greatly improves the sewage treatment efficiency and increases the sewage treatment capacity; the sewage can be treated more thoroughly and the treatment effect is better.

Description of drawings

In order to illustrate the embodiments of the present invention or the technical solutions in the prior art more clearly, the following briefly introduces the drawings that are required in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only These are some embodiments of the present invention, and for those of ordinary skill in the art, other drawings can also be obtained from these drawings without creative effort.

Fig. 1: the structural representation of a kind of electrochemical oxidation process sewage treatment device of the present invention;

Among them: 1- power supply device, 3- purification tank, 5- overflow wall, 21- flow electrolytic cell, 22- stationary electrolytic cell, 31- zeolite, 32- crushed stone, 41- anode plate, 42- cathode plate , 61-water inlet, 62-water outlet, 211-stirring bar, 212-particle electrode in flow electrolytic cell, 221-particle electrode in stationary electrolytic cell.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present invention.

Example 1

As shown in FIG. 1 , a device for treating sewage by electrochemical oxidation method includes a power supply device 1 , two electrolytic cells and a purification cell 3 . The sewage treatment device in this embodiment adopts a three-dimensional particle electrode reaction system, and uses the principle of electrochemical oxidation to treat sewage. The three-dimensional particle electrode reaction system of the electrolysis cell is composed of: an anode plate 41 and a cathode plate 42 are respectively arranged on the two side walls in the electrolysis cell, the particle electrode is filled in the electrolysis cell, the positive electrode of the power supply device 1 is connected with the anode plate 41 in the electrolysis cell by a wire, and the power supply device The negative electrode of 1 is connected to the cathode plate 42 in the electrolytic cell by a wire. Preferably, the anode plate 41 is a Ti/PbO ₂ -La electrode, and the cathode plate 42 is foamed nickel. Among them, the Ti/PbO ₂ -La electrode is an electrode prepared by coating a titanium plate with PbO ₂ and La on a titanium plate as a base material. More preferably, the distance between the anode plate 41 and the cathode plate 42 is 75-80 mm, and the areas of the anode plate 41 and the cathode plate 42 are both 56-64 cm ² .

Between the electrolytic cells, between the electrolytic cells and the purification pool 3 are all communicated through the overflow wall 5. The setting of the overflow wall 5 can greatly reduce the energy provided by the outside world to the entire device, and can save energy consumption. Preferably, the height of the overflow wall 5 is lower than the height of the walls of the electrolytic cell and the purification cell 3 . Wherein, the upper part of the first flow electrolytic cell is provided with a water inlet 61 , and the lower part of the purification tank 3 is provided with a water outlet 62 .

As shown in FIG. 1 , the electrolysis cell includes a flow type electrolysis cell 21 and a stationary type electrolysis cell 22, and is arranged in a flow type-stationary type.

Furthermore, in order to speed up the sewage treatment speed in the flow electrolytic cell 21 , a stirring rod 211 is provided inside the flow electrolytic cell 21 . Because to improve the efficiency of sewage treatment, the conductivity in the solution needs to be increased, and the conductive material needs to choose a material with better conductivity; at the same time, the cost of the conductive material must be considered. Then the three metals of iron, nickel and manganese satisfy the above selection conditions for conductive materials. The stirring rod 211 is an alloy made according to a mass ratio of iron: nickel: manganese of 2-4:1-3:1-3. Preferably, the stirring rod 211 is made according to the ratio of iron: nickel: manganese mass ratio of 3:1:1, which can improve the conductivity by at least 17% compared with other ratios, and the effect of sewage treatment is also the best.

Further, the particle electrode 212 filled in the flow electrolytic cell 21 is cylindrical, with a length of 1-3 mm and a diameter of 2-4 mm; the density of the particle electrode 212 filled in water is 400-500 mg/l. Such particles can float well in water, and at the same time, such particle electrodes are easy to produce and conduct electricity well. Among them, the particle electrode 212 is three particle electrodes of iron particle electrode, nickel particle electrode and manganese particle electrode, that is, iron particle electrode, nickel particle electrode and manganese particle electrode are respectively made of iron, nickel and manganese into cylindrical shape according to the above-mentioned size, Then, the iron particle electrode, the nickel particle electrode and the manganese particle electrode are directly filled in the electrolytic solution of the flow electrolytic cell 21—water. The particle electrode 212 and the stirring rod 211 filled in the flow electrolytic cell 21 are all made of the same material—iron, nickel, and manganese, which avoids excessive conductive particles from forming a short-circuit current between the solutions, resulting in a reduction in the reaction current, and finally making the Organic matter treatment efficiency is reduced.

Further, the particle electrode 221 filled in the stationary electrolytic cell 22 is an activated carbon electrode, and the activated carbon electrode is an activated carbon electrode having a porous structure. Activated carbon as an electrode has adsorption function, which can adsorb organic matter in water, and it has strong adaptability to changes in water temperature, water quality and water quantity. Preferably, the diameter of the activated carbon electrode is 5-15 mm, and the pore diameter of the activated carbon electrode is 20-30 μm;

It is common in the prior art to use a flow-type three-dimensional particle electrolytic cell or a stationary three-dimensional particle electrolytic cell alone to treat sewage, which will result in unclean and incomplete sewage treatment. In this embodiment, the sewage is first treated by the flowing electrolytic cell 21. The flowing electrolytic cell 21 can perform large batch processing of sewage, and the treatment effect is better than that of the fixed electrolytic cell 22. In addition, there is a stirring rod 211 The accelerated treatment can quickly reduce the pollution degree of sewage. Then, the sewage treated by the flow electrolytic cell 21 flows into the fixed electrolytic cell 22, and the fixed electrolytic cell 22 can further adsorb and treat the sewage, and can further purify the sewage. If the sewage is treated with a fixed electrolytic cell first, the reaction time will be slow, and it will be easy to block, and the sewage treatment effect is very insignificant.

Further, the purification tank 3 is filled with a matrix material layer, and the matrix material layer includes zeolite 31 and crushed stone 32, which are alternately arranged. The water treated by the electrolytic cell flows out from the water outlet 62 of the purification tank 3 after being filtered again by the zeolite 31 and the crushed stone 32 filled in the purification tank 3 .

Example 2

Use the electrochemical oxidation method in the embodiment 1 to treat sewage, and the specific method includes the following steps:

(1) Before the sewage to be treated enters the sewage treatment device, the sewage needs to be pretreated, that is, a flocculant is added to the sewage to be treated to precipitate impurities in the sewage;

(2) the sewage treatment device is placed horizontally, and the flow electrolytic cell 21 and the fixed electrolytic cell 22 are alternately arranged; open the power supply device 1 and the stirring rod 211, and adjust the power supply voltage of the power supply device 1;

(3) the sewage pretreated in step 1 enters the flow electrolytic cell 21 from the water inlet 61, and flows into the stationary electrolytic cell 22 through the overflow wall 5; the pretreated sewage is processed by at least two electrolytic cells Afterwards, it flows into the purification tank 3 through the overflow wall 5 for purification treatment; the water flow velocity of the water inlet 61 and the water outlet 62 is controlled to be equal;

(4) Collect the treated water flowing out from the water outlet 62 .

The specific parameters are as follows: the mass concentration of the sewage water sample is 300 mg/L. The power supply voltage of the power supply device 1 is 5V, and the current density between the anode plate 41 and the cathode plate 42 is 2mA/cm ² ; the electrification time of each electrolytic cell is 90min; the water flow velocity of the water inlet 61 and the water outlet 62 is 15ml /s. The distance between the anode plate 41 and the cathode plate 42 is 75 mm, and the areas of the anode plate 41 and the cathode plate 42 are both 56 cm ² . The stirring rod 211 is made according to the mass ratio of iron: nickel: manganese of 2:1:1. The particle electrode 212 filled in the flow electrolytic cell 21 is an iron particle electrode, a nickel particle electrode, and a manganese particle electrode having a length of 1 mm and a diameter of 2 mm, and the iron particle electrode: the nickel particle electrode: the manganese particle electrode is 1 according to the mass ratio: The ratio of 1:1 is mixed and filled in water, and the density of filling in water is 400mg/l. The diameter of the activated carbon electrode is 5 mm, and the pore size of the activated carbon electrode is 20 μm.

Example 3

Use the electrochemical oxidation method in the embodiment 1 to treat the sewage, wherein, in this embodiment, 4 electrolytic cells are set up, and they are alternately arranged according to the flow type-fixed type-flow type-fixed type, and the specific method is the same as the embodiment 2, It will not be repeated here.

The specific parameters are as follows: the mass concentration of the sewage water sample is 300 mg/L. The power supply voltage of the power supply device 1 is 6.5V, and the current density between the anode plate 41 and the cathode plate 42 is 4mA/cm ² ; the electrification time of each electrolytic cell is 106min; the water flow velocity of the water inlet 61 and the water outlet 62 is 18ml/s. The distance between the anode plate 41 and the cathode plate 42 is 76.5 mm, and the areas of the anode plate 41 and the cathode plate 42 are both 58 cm ² . The stirring rod 211 is made according to the ratio of iron: nickel: manganese mass ratio of 3:1:1. The particle electrode 212 filled in the flow electrolytic cell 21 is an iron particle electrode, a nickel particle electrode, and a manganese particle electrode having a length of 1.5 mm and a diameter of 2.6 mm, and the iron particle electrode: nickel particle electrode: manganese particle electrode according to the mass ratio: The ratio of 1:2:3 is mixed and filled in water, and the density of filling in water is 450mg/l. The diameter of the activated carbon electrode is 7 mm, and the pore size of the activated carbon electrode is 23 μm.

Example 4

Use the electrochemical oxidation method in the embodiment 1 to treat the sewage, wherein, in this embodiment, 4 electrolytic cells are set up, and they are alternately arranged according to the flow type-fixed type-flow type-fixed type, and the specific method is the same as the embodiment 2, It will not be repeated here.

The specific parameters are as follows: the mass concentration of the sewage water sample is 300 mg/L. The power supply voltage of the power supply device 1 is 8V, and the current density between the anode plate 41 and the cathode plate 42 is 6mA/cm ² ; the electrification time of each electrolytic cell is 110min; the water flow velocity of the water inlet 61 and the water outlet 62 is 20ml /s. The distance between the anode plate 41 and the cathode plate 42 is 78 mm, and the areas of the anode plate 41 and the cathode plate 42 are both 61 cm ² . The stirring rod 211 is made according to the ratio of iron: nickel: manganese mass ratio of 3:2:2. The particle electrode 212 filled in the flow electrolytic cell 21 is an iron particle electrode, a nickel particle electrode, and a manganese particle electrode having a length of 2 mm and a diameter of 3.2 mm, and the iron particle electrode: nickel particle electrode: manganese particle electrode according to the mass ratio of 2 : The ratio of 1:4 is mixed and filled in water, and the density of filling in water is 480mg/l. The diameter of the activated carbon electrode is 12 mm, and the pore size of the activated carbon electrode is 27 μm.

Example 5

Sewage is treated by using the electrochemical oxidation method for sewage treatment device in Example 1. In this example, 6 electrolytic cells are set up, and they are arranged alternately according to flow-fixed-flow-fixed-flow-fixed. The method is the same as that of Embodiment 2, and will not be repeated here.

The specific parameters are as follows: the mass concentration of the sewage water sample is 300 mg/L. The power supply voltage of the power supply device 1 is 9V, and the current density between the anode plate 41 and the cathode plate 42 is 8mA/cm ² ; the electrification time of each electrolytic cell is 120min; the water flow velocity of the water inlet 61 and the water outlet 62 is 23ml /s. The distance between the anode plate 41 and the cathode plate 42 is 80 mm, and the areas of the anode plate 41 and the cathode plate 42 are both 64 cm ² . The stirring rod 211 is made according to the ratio of iron: nickel: manganese mass ratio of 4:3:3. The particle electrode 212 filled in the flow electrolytic cell 21 is an iron particle electrode, a nickel particle electrode, and a manganese particle electrode having a length of 3 mm and a diameter of 4 mm, and the iron particle electrode: the nickel particle electrode: the manganese particle electrode is 3 according to the mass ratio: The ratio of 2:4 is mixed and filled in water, and the density of filling in water is 500mg/l. The diameter of the activated carbon electrode is 15 mm, and the pore size of the activated carbon electrode is 30 μm.

Comparative Example 1

In this comparative example, the electrolytic cell in Example 1 is changed to only a flowing electrolytic cell, and the rest remain unchanged, and the concrete method for treating sewage is as follows:

(1) Before the sewage to be treated enters the sewage treatment device, the sewage needs to be pretreated, that is, a flocculant is added to the sewage to be treated to precipitate impurities in the sewage;

(2) Place the sewage treatment device horizontally, turn on the power supply device and stirring rod, and adjust the power supply voltage of the power supply device;

(3) the sewage through the pretreatment of step 1 is processed by the water inlet into the flow electrolytic cell and flows into the purification tank through the overflow wall 5 to carry out purification treatment; Control the water flow velocity of the water inlet and the water outlet to be equal;

(4) Collect the treated water flowing out from the water outlet.

The specific parameters are as follows: the mass concentration of the sewage water sample is 300 mg/L. The power supply voltage of the power supply device is 5V, the current density between the anode plate and the cathode plate is 2mA/cm ² ; the electrification time of the electrolytic cell is 90min; the water flow rate of the water inlet and the water outlet is 15ml/s. The distance between the anode plate and the cathode plate was 75 mm, and the area of the anode plate and the cathode plate were both 56 cm ² . The stir bar was made with a mass ratio of iron:nickel:manganese of 2:1:1. The particle electrodes filled in the flow electrolytic cell are iron particle electrodes, nickel particle electrodes, and manganese particle electrodes with a length of 1 mm and a diameter of 2 mm, and the iron particle electrode: nickel particle electrode: manganese particle electrode is in a mass ratio of 1:1:1 The proportion of mixed filling in water, the density of filling in water is 400mg/l.

Comparative Example 2

In this comparative example, the electrolytic cell in Example 1 is changed to only one fixed electrolytic cell, and the rest remain unchanged, and the concrete method for treating sewage is as follows:

(1) Before the sewage to be treated enters the sewage treatment device, the sewage needs to be pretreated, that is, a flocculant is added to the sewage to be treated to precipitate impurities in the sewage;

(2) Place the sewage treatment device horizontally, turn on the power supply device and adjust the power supply voltage of the power supply device;

(3) the sewage that has been pretreated in step 1 is processed by the water inlet into the stationary electrolytic cell and flows into the purification tank through the overflow wall for purification treatment; the water flow velocity of the water inlet and the water outlet is controlled to be equal;

(4) Collect the treated water flowing out from the water outlet.

The specific parameters are as follows: the mass concentration of the sewage water sample is 300 mg/L. The power supply voltage of the power supply device is 5V, the current density between the anode plate and the cathode plate is 2mA/cm ² ; the electrification time of the electrolytic cell is 90min; the water flow rate of the water inlet and the water outlet is 15ml/s. The distance between the anode plate and the cathode plate was 75 mm, and the area of the anode plate and the cathode plate were both 56 cm ² . The diameter of the activated carbon electrode is 5 mm, and the pore size of the activated carbon electrode is 20 μm.

Comparative Example 3

In this comparative example, the electrolytic cell in Example 1 is changed to 2 electrolytic cells set according to the fixed-flow type, and the rest remain unchanged, and the concrete method for treating sewage is as follows:

(1) Before the sewage to be treated enters the sewage treatment device, the sewage needs to be pretreated, that is, a flocculant is added to the sewage to be treated to precipitate impurities in the sewage;

(2) The sewage treatment device is placed horizontally, and the fixed electrolytic cell and the mobile electrolytic cell are alternately arranged; the power supply device and the stirring rod are turned on, and the power supply voltage of the power supply device is adjusted;

(3) the sewage pretreated in step 1 is entered into the stationary electrolytic cell from the water inlet, and flows into the flowing electrolytic cell through the overflow wall; after the treatment, it flows into the purification tank through the overflow wall for purification treatment; control The water flow velocity of the water inlet and the water outlet are equal;

(4) Collect the treated water flowing out from the water outlet.

The specific parameters are as follows: the mass concentration of the sewage water sample is 300 mg/L. The power supply voltage of the power supply device 1 is 5V, the current density between the anode plate and the cathode plate is 2mA/cm ² ; the electrification time of each electrolytic cell is 90min; the water flow rate of the water inlet and the water outlet is 15ml/s. The distance between the anode plate and the cathode plate was 75 mm, and the area of the anode plate and the cathode plate were both 56 cm ² . The stir bar is made with a mass ratio of iron:nickel:manganese of 2:1:1. The particle electrodes filled in the flow electrolytic cell are iron particle electrodes, nickel particle electrodes, and manganese particle electrodes with a length of 1 mm and a diameter of 2 mm, and the iron particle electrode: nickel particle electrode: manganese particle electrode is in a mass ratio of 1:1:1 The proportion of mixed filling in water, the density of filling in water is 400mg/l. The diameter of the activated carbon electrode is 5 mm, and the pore size of the activated carbon electrode is 20 μm.

Comparative Example 4

In this comparative example, the material of the stirring rod in the flow electrolytic cell in Example 1 is changed to iron, and the particle electrode in the flow electrolytic cell is an iron electrode, wherein, four electrolytic cells are set in this comparative example, and the flow type-fixed type - The flow type and the fixed type are alternately set, and the rest remain unchanged. The specific method is the same as that of Embodiment 2, and will not be repeated here.

The specific parameters are as follows: the mass concentration of the sewage water sample is 300 mg/L. The power supply voltage of the power supply device is 6.5V, the current density between the anode plate and the cathode plate is 4mA/cm ² ; the electrification time of each electrolytic cell is 106min; the water flow rate of the water inlet and outlet is 18ml/s. The distance between the anode plate and the cathode plate was 76.5 mm, and the area of the anode plate and the cathode plate were both 58 cm ² . The stirring rod is made of iron. The particle electrode filled in the flow electrolytic cell is iron, with a length of 1.5 mm, a diameter of 2.6 mm, and a density of 450 mg/l filled in water. The diameter of the activated carbon electrode is 7 mm, and the pore size of the activated carbon electrode is 23 μm.

Comparative analysis:

The water treated by Examples 2 to 5 and Comparative Examples 1 to 4 was collected and tested, and the test results are shown in Table 1. Among them, COD refers to chemical oxygen demand and TOC refers to total organic carbon.

Table 1

1. The difference between Example 2 and Comparative Example 1 and Comparative Example 2 is that the types of electrolytic cells are different, that is, two electrolytic cells are provided in Example 2, and are set according to the flow-fixed type, and only set in Comparative Example 1 A flowing electrolytic cell, only one stationary electrolytic cell is provided in Comparative Example 2. From the data in Table 1, it can be seen that the effect of sewage treatment in Example 2 is obviously better than that of Comparative Example 1 and Comparative Example 2, that is, the removal rate of COD and TOC in Example 2 is significantly higher than that of Comparative Example 1, Comparative Example 2. It is common in the prior art to use a flow-type three-dimensional particle electrolytic cell or a stationary three-dimensional particle electrolytic cell alone to treat sewage, which will result in unclean and incomplete sewage treatment.

2. The difference between Example 2 and Comparative Example 3 is that the setting mode of the electrolytic cell is different, that is: the pretreated sewage in Example 2 first enters the mobile electrolytic cell, and then enters the stationary electrolytic cell, while the pretreatment in Comparative Example 3 The sewage first enters the stationary electrolytic cell, and then enters the flowing electrolytic cell. From the data in Table 1, it can be seen that the effect of sewage treatment in Example 2 is obviously better than that in Comparative Example 3, that is, the removal rate of COD and TOC in Example 2 is significantly higher than that of Comparative Example 3. In Example 2, the first step of treatment of sewage is carried out through the flow electrolytic cell. The flow electrolytic cell can carry out large-scale treatment of sewage, which is better than the fixed electrolytic cell. Quickly reduce the pollution degree of sewage. Then the sewage treated by the flow electrolytic cell flows into the fixed electrolytic cell, and the fixed electrolytic cell can further adsorb and treat the sewage, which can further purify the sewage. In Comparative Example 3, the sewage first enters the stationary electrolytic cell, and then enters the flowing electrolytic cell, which will cause slow reaction time and easy blockage, and the sewage treatment effect is very insignificant.

3. The difference between Example 3 and Comparative Example 4 is that the materials of the three-dimensional particle electrode and the stirring rod in the flow electrolytic cell are different, namely: the three-dimensional particle electrode in Example 3 is an iron particle electrode, a nickel particle electrode, and a manganese particle electrode, In Comparative Example 4, only a single iron particle electrode was used. From the data in Table 1, it can be seen that the effect of sewage treatment in Example 3 is obviously better than that of Comparative Example 4, that is, the removal rate of COD and TOC in Example 3 is significantly higher than that of Comparative Example 4. At the same time, the embodiment The current efficiency in 3 is significantly higher than that in Comparative Example 4. Using a variety of particle electrodes in Example 3, compared with the use of a single particle in Comparative Example 4, the current efficiency and sewage treatment capacity are improved, so that the sewage treatment efficiency is higher, and the sewage treatment capacity is also greatly improved.

4. In Example 2, Example 4, and Example 5, 2, 4, and 6 electrolytic cells were set up respectively, and they were arranged alternately according to the flow type and the fixed type. From the data in Table 1, it can be seen that the sewage is processed by multiple electrolytic cells to achieve multi-stage treatment, which makes the treatment more thorough. This embodiment does not further limit the number of electrolytic cells, and those skilled in the art can choose by themselves according to actual needs.

This embodiment does not further limit the mass ratios of the iron particle electrodes, nickel particle electrodes, and manganese particle electrodes filled in the water in the flow electrolytic cell, and those skilled in the art can choose by themselves according to actual needs.

The above descriptions are only the embodiments of the present invention, and are not intended to limit the scope of the present invention. Any equivalent structure or equivalent process transformation made by using the contents of the description and drawings of the present invention, or directly or indirectly applied to other related technologies Fields are similarly included in the scope of patent protection of the present invention.

Claims (9)

1. A device for treating sewage by an electrochemical oxidation method, characterized in that it comprises a power supply device (1), at least two electrolytic cells and a purification cell (3); wherein: the electrolytic cell comprises a flow electrolytic cell (21) and A stationary electrolytic cell (22) is arranged alternately; an anode plate (41) and a cathode plate (42) are respectively provided on the two side walls in the electrolytic cell, and particle electrodes are filled in the electrolytic cell; the flowing electrolytic cell (21) A stirring rod (211) is arranged inside, and the stirring rod (211) is made according to the ratio of iron: nickel: manganese mass ratio of 2-4:1-3:1-3; The positive electrode is connected with the anode plate (41) in the electrolytic cell by a wire, and the negative electrode of the power supply device (1) is connected with the cathode plate (42) in the electrolytic cell by a wire; between the electrolytic cells, the electrolytic cell and the purification The pools (3) are connected through the overflow wall (5); the upper part of the first flow electrolytic cell is provided with a water inlet (61), and the lower part of the purification pool (3) is provided with a water outlet (62). 2. The device for treating sewage by electrochemical oxidation method according to claim 1, wherein the particle electrode (212) filled in the flow electrolytic cell (21) is cylindrical, and the length is 1-3mm, and the diameter is 1-3mm. is 2-4 mm; the density of the particle electrode (212) filled in water is 400-500 mg/L. 3 . The device for treating sewage by electrochemical oxidation method according to claim 2 , wherein the particle electrodes ( 212 ) are three types of particle electrodes: iron particle electrodes, nickel particle electrodes and manganese particle electrodes. 4 . 4. The device for treating sewage by an electrochemical oxidation method according to claim 1, wherein the particle electrode (221) filled in the stationary electrolytic cell (22) is an activated carbon electrode, and the activated carbon electrode has pores Activated carbon electrode with a shape structure; wherein: the diameter of the activated carbon electrode is 5-15 mm, and the aperture of the activated carbon electrode is 20-30 μm; the height of the activated carbon electrode filled in the stationary electrolytic cell (22) is lower than that of the activated carbon electrode. Height of overflow wall (5). 5. The device for treating sewage by electrochemical oxidation according to any one of claims 1-4, wherein the anode plate (41) is a Ti/PbO ₂ -La electrode, and the cathode plate (42) is a Ti/PbO 2 -La electrode. ) is nickel foam; the distance between the anode plate (41) and the cathode plate (42) is 75-80mm, and the area of the anode plate (41) and the cathode plate (42) is both 56-64cm ² . 6 . The device for treating sewage by electrochemical oxidation method according to claim 5 , wherein the purification tank ( 3 ) is filled with a matrix material layer, and the matrix material layer comprises zeolite ( 31 ) and crushed stone ( 32 ). 7 . , and set them alternately. 7 . The device for treating sewage by electrochemical oxidation method according to claim 6 , wherein the height of the overflow wall ( 5 ) is lower than the height of the walls of the electrolytic cell and the purification pool ( 3 ). 8 . 8. A method for treating sewage, using the device for treating sewage by electrochemical oxidation according to any one of claims 1-7, characterized in that, comprising the steps: (1) Before the sewage to be treated enters the sewage treatment device, the sewage needs to be pretreated, that is, a flocculant is added to the sewage to be treated to precipitate impurities in the sewage; (2) The sewage treatment device is placed horizontally, and the flowing electrolytic cell (21) and the stationary electrolytic cell (22) are alternately arranged; open the power supply device (1) and the stirring rod (211), and adjust the the supply voltage of the power supply device (1); (3) Entering the sewage pretreated in step (1) into the flow electrolytic cell (21) through the water inlet (61), and into the stationary electrolysis cell through the overflow wall (5) in the pool (22); make the pretreated sewage flow into the purification pool (3) through the overflow wall (5) after being processed by at least two of the electrolytic cells for purification treatment; control the water inlet ( 61) and the water flow velocity of the water outlet (62) is equal; (4) Collect the treated water flowing out from the water outlet (62). 9. The method for treating sewage according to claim 8, wherein the power supply voltage of the power supply device (1) is 5-9V, and the current density between the anode plate (41) and the cathode plate (42) is is 2-8 mA/cm ² ; the electrification time of each of the electrolytic cells is 90-120 min; the water flow rates of the water inlet (61) and the water outlet (62) are both 15-23 ml/s.

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