KR102044024B1 - Plasma electrode, plasma electrode module and water treatment apparatus containing the same - Google Patents

Abstract

The present invention relates to a water treatment apparatus using plasma underwater discharge and a water treatment system including the same, and more particularly, a water treatment apparatus capable of decomposing organic matter or removing microorganisms present in the water to be treated using a plasma nozzle, and the same. It relates to a water treatment system comprising. To this end, the water treatment apparatus includes a reactor having an inlet through which the water to be treated is introduced and an outlet through which the purified water is discharged; A ground electrode provided at one side of the reactor; And a plasma nozzle provided at one side of the reactor and generating a plasma.

Description

Plasma electrode for water treatment, plasma electrode module and water treatment system including same {PLASMA ELECTRODE, PLASMA ELECTRODE MODULE AND WATER TREATMENT APPARATUS CONTAINING THE SAME}

The present invention relates to a water treatment apparatus using plasma underwater discharge, and more particularly, a plasma electrode capable of decomposing organic matter or removing microorganisms present in the water to be treated using a plasma electrode or a plasma electrode module including the same. The present invention relates to a water treatment apparatus including a plasma electrode module.

As a general wastewater treatment method, a sedimentation method of sedimenting contaminants and sediment water after sedimenting the contaminants by securing a large space for sedimentation of contaminants has been used. However, this precipitation method takes a lot of time and has the disadvantage of securing a large site, and there are side effects such as decay of the precipitate and generation of odor.

Accordingly, several water treatment devices have been developed to separate and separate wastewater from pollutants even in confined spaces.In the currently used method, bubbles are generated in the wastewater by adsorbing fine contaminants to the air bubbles and floating on the surface of the wastewater. There is a pressurized flotation method.

The most frequently used water treatment method of the pressure floating method is Dissolved Air Flatation, which is widely used in wastewater treatment plants. This is achieved by injecting saturated water above atmospheric pressure into the floating tank through nozzles or needle valves. (100um or less).

However, the existing dissolved air flotation method has a disadvantage that the flow rate that can be processed in a predetermined area is applicable only to small-scale processes, size control is not possible once installed because the bubble size is controlled by the nozzle structure. In addition, since the pressurized tank for making water saturated above atmospheric pressure requires high power, the power cost of the pressurized tank has a disadvantage in that a large portion of the operating cost of the water treatment device is present. In addition, in the case of organic matter such as algae, it is difficult to adhere to the flocculation floc and is often suspended, which makes it difficult to process the precipitation and flotation processes. In order to solve this disadvantage, the method of injecting chlorine has been improved, but a new problem such as a corrosion problem has occurred due to the excessive injection of chlorine.

Therefore, the development of a water treatment apparatus capable of effectively removing organic matter and microorganisms present in the water to be treated while excluding the above disadvantages is required.

Republic of Korea Patent Publication No. 10-0174364 Republic of Korea Utility Model Registration No. 20-0212210

The present invention is to solve the above problems, an object of the present invention to provide a water treatment apparatus and a water treatment system that can decompose organic matter or remove microorganisms present in the water to be treated by using a plasma nozzle and a water treatment system comprising the same. have.

These and other objects and advantages of the present invention will become apparent from the following description of preferred embodiments.

The plasma electrode for water treatment according to an embodiment of the present invention has a multi-stage structure in which a ground part 33, a fixing part 32, and a discharge part 31 having a circumferential shape are sequentially stacked, and the ground part 33 is In contact with the electrode, plasma is generated in the discharge part 31.

The ground portion 33, the fixing portion 32 and the discharge portion 31 is preferably an integral structure made of the same material having corrosion resistance, and the ground portion 33, the fixing portion 32 and the discharge portion ( It is preferable that the ratio of the diameter of 31) is 7-8: 4-6: 1.

In addition, it is preferable that the ratio of the height of the ground part 33, the fixing part 32, and the discharge part 31 is 1-2: 1: 1, and the water treatment which has an integrated structure according to one embodiment of the present invention. The plasma electrode is preferably a metal material having corrosion resistance, and in consideration of durability and workability, it is more preferable to use a SUS material which is stainless steel.

Another embodiment of the present invention includes a plasma electrode module for water treatment, comprising: a conductive substrate having a plurality of holes formed therein; A ceramic layer surrounding the outer circumference of the tungsten base except for the hole; And a plasma electrode positioned inside the hole and having a multi-stage structure in which a ground part 33 having a circumferential shape, a fixing part 32, and a discharge part 31 are sequentially stacked. The ground part 33 Is in contact with the conductive substrate, and plasma is generated in the discharge part 31.

As the conductive substrate, a tungsten alloy material such as tungsten or tungsten nitride having high electrical conductivity and excellent durability is preferably used. The plasma electrode included in the plasma electrode module may include a ground part 33 and a fixing part 32. And the discharge portion 31 is preferably an integral structure made of the same material having corrosion resistance, the material having corrosion resistance while forming the integral structure is more preferably made of SUS material.

It is preferable that the ratio of the diameter of the ground part 33, the fixed part 32, and the discharge part 31 of the said plasma electrode is 7-8: 4-6: 1, The ground part 33 and the fixed part 32 ) And the height of the discharge portion 31 is preferably 1-2: 1: 1.

The conductive substrate may be in the form of a plate or cylinder, and tungsten material is preferably used.

In another embodiment of the present invention, a water treatment apparatus including such a plasma electrode or a plasma electrode module may include a reactor having an inlet through which the water to be treated is introduced and an outlet through which the purified water is discharged; A ground electrode provided at one side of the reactor; And a plasma electrode module provided at one side of the reactor and generating plasma, wherein the plasma electrode module comprises: a tungsten substrate having a plurality of holes formed therein; A ceramic layer surrounding the outer circumference of the tungsten base except for the hole; And a plasma electrode positioned inside the hole and having a multi-stage structure in which a ground part 33, a fixing part 32, and a discharge part 31 are stacked in this order. The ground part 33 Is in contact with the tungsten substrate, characterized in that the plasma is generated in the discharge portion (31).

In the reactor, it is preferable that the inlet and the outlet are provided at the same side, or the inlet, the outlet and the ground electrode are provided at the same side, and the ground electrode and the plasma electrode module may be installed to face each other.

The reactor may further include a distance adjusting unit for adjusting a distance between the ground electrode and the plasma electrode module, wherein the ground electrode is preferably in a plate shape.

According to the present invention, the plasma underwater discharge has the effect of effectively decomposing or removing organic matter and microorganisms present in the water to be treated.

In particular, the distance between the ground electrode and the plasma nozzle provided in the reactor can be easily adjusted, and the plasma can be stably generated by using an integrated plasma nozzle composed of three stages, thereby improving the treatment efficiency of the water to be treated. Has an effect.

In addition, the plasma electrode for water treatment according to an embodiment of the present invention, the discharge portion, the fixing portion and the grounding portion is made integrally, excellent durability, can generate a stable plasma, the electrode module provided with a plurality of electrodes It can be applied in the form of to prevent the phenomenon of breaking by applying more power than necessary to one electrode, or the breakdown phenomenon of the local site.

In addition, the three-stage configuration with different lengths and diameters not only improves grounding efficiency and discharge efficiency, but also generates a large amount of OH radicals through stable plasma generation, effectively decomposing organic pollutants contained in the treated water. have.

Such effects of the present invention are not limited to the above-mentioned effects, and other effects not mentioned will be clearly understood by those skilled in the art from the following description.

1 is a view schematically showing a water treatment device according to an embodiment of the present invention.
2 is a view schematically showing a water treatment device according to an embodiment of the present invention.
3 is a view for explaining the principle and effect of the plasma generation.
4 is a view schematically showing a plasma nozzle according to an embodiment of the present invention.
5 is a view schematically showing a plasma electrode module according to an embodiment of the present invention.
6 is a water treatment system in which a water treatment apparatus according to an embodiment of the present invention is connected in series.
7 is a water treatment system parallel to the water treatment apparatus according to an embodiment of the present invention.

Hereinafter, the present invention will be described in detail with reference to embodiments and drawings of the present invention. These examples are only presented by way of example only to more specifically describe the present invention, it will be apparent to those skilled in the art that the scope of the present invention is not limited by these examples. .

Also, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs, and in the case of conflict, the specification including definitions The description of will prevail.

In the drawings, parts irrelevant to the description are omitted to clearly describe the proposed invention, and like reference numerals designate like parts throughout the specification. In addition, when a part "contains" a certain component, this means that the component may further include other components, without excluding other components, unless specifically stated otherwise. In addition, the "unit" described in the specification means one unit or block that performs a specific function.

In each step, an identification code (first, second, etc.) is used for convenience of description, and the identification code does not describe the order of each step, and each step does not explicitly describe a specific order in context. It may be carried out in a different order than described above. That is, each step may be performed in the same order as specified, may be performed substantially simultaneously, or may be performed in the reverse order.

1 and 2 are diagrams schematically showing the water treatment device 100 according to an embodiment of the present invention, respectively. 1 and 2, a water treatment device 100 according to an embodiment of the present invention includes a reactor including an inlet 11 through which water to be treated is introduced and an outlet 12 through which purified water is discharged. 10; A ground electrode 20 provided at one side of the reactor 10; And a plasma electrode 30 provided at one side of the reactor 10 to generate plasma. The present invention has the effect of decomposing or removing organic matter and microorganisms present in the water to be treated through plasma underwater discharge using the plasma electrode 30.

Conventionally, bio-fouling formed by organic materials is suppressed by injecting chlorine before pretreatment of treated water such as seawater, but problems such as corrosion occur due to excessive injection of chlorine. By replacing the chlorine injection method with a plasma method, by effectively removing organic matter and microorganisms, there is an advantage that does not cause a corrosion problem while suppressing a bio-fouling phenomenon.

3 is a view for explaining the principle and effect of the plasma generation, before explaining the present invention in detail, will be described with respect to the effect of the water treatment using the plasma underwater discharge with reference to FIG.

In the plasma underwater discharge, corona discharge, arc discharge, or the like can be used by varying pulses, voltages, and the like applied to the plasma electrode. The effects of water treatment using plasma are cell destruction by shock waves, cell destruction by ultrasonic waves, and cell destruction by high voltage electric fields. This will be described in more detail as follows.

First, in cell destruction by shock waves, shock waves appearing as sudden pressure fluctuations can lead to cell destruction. At this time, the destruction of the cell depends on the size of the cell and the shape of the cell, the thickness of the cell and the like, and depends on the shock wave intensity.

In addition, there is a cell destruction by ultrasonic waves, which can cause cavitation (Cavitation) phenomenon while passing through the liquid. Cavitation is a bubble (bubble) in which the density of liquid is small and dense by creating a longitudinal wave that vibrates by the vibrator when ultrasonic waves pass through the liquid medium by the ultrasonic vibrator. It is a phenomenon that explodes. It is a method used when destroying a cell using a shock wave caused by the explosion and destroying a small amount of microbial cells.

In addition, cell destruction by a high voltage electric field induces a high potential difference in the cell membrane to destroy an insulator called a cell membrane. Therefore, the survival rate of plankton and bacteria can be drastically reduced by the action of ultraviolet rays, active species, shock waves, bubbles, etc. generated by plasma treatment.

 In one embodiment, the reactor 10 has an inlet 11 through which the water to be treated flows in and a discharge port 12 through which the water to be treated is discharged, and accommodates the water therein. The reactor 10 is not particularly limited and can be manufactured in various shapes, and generally can be manufactured in a rectangular parallelepiped shape. One side of the reactor 10 may be provided with a ground electrode 20, and the other side may be provided with a plasma electrode 30 for generating a plasma. Although the position of the inlet 11 and the outlet 12 is not specifically limited, It is preferable that the inlet 11 and the outlet 12 are located in the same side (in the case of a cuboid shape, it means the same side). In addition, the ground electrode 20, the inlet 11, and the outlet 12 may be provided at the same side, and the plasma electrode 30 may be installed to face the ground electrode 20. In this case, the flat ground electrode 20 may form an upper surface of the reactor 10 (see FIG. 1), and may form an inlet 11 and an outlet 12 in the ground electrode 20. .

In one embodiment, the reactor 10 may include a distance adjuster 40 (see FIG. 2) to adjust the distance between the ground electrode 20 and the plasma electrode 30. According to the type of water to be treated, the voltage applied to the plasma electrode 30 or the distance between the ground electrode 20 and the plasma electrode 30 can be adjusted. The distance controller 40 is provided on both sides of the reactor 10. It is formed to face the elongation or contraction of the height of the reactor 10 to adjust the treated water capacity of the reactor 10 and at the same time can adjust the distance between the ground electrode 20 and the plasma electrode 30.

In one embodiment, the ground electrode 20 may be a conventional electrode, and may be provided on one side of the reactor 10, as described above, may be formed in a flat plate form one surface of the reactor 10 It may be. The ground electrode 20 is electrically connected (contacted) with the water to be treated so that the water can be grounded.

In one embodiment, the plasma electrode 30 may be manufactured using tungsten or stainless steel, and may be connected to a power supply (not shown). The power supply unit may apply a pulse, alternating current, or direct current voltage to the plasma electrode 30. The plasma electrode 30 may be provided at one side of the reactor 10, but may be formed separately, but may be positioned inside the reactor in the form of a plasma electrode module 50 in which a plurality of plasma electrodes are collected. It is preferable to be installed opposite to 20). In addition, the plasma electrode module 50 may be provided in plural in the reactor according to the throughput of the water to be treated.

4 is a diagram schematically illustrating a plasma electrode 30 according to an example. Referring to FIG. 4, the plasma electrode 30 will be described in detail. The plasma electrode 30 may be formed in an integrated structure including a discharge part 31, a fixing part 32, and a ground part 33. . Since it is manufactured integrally, it is possible to prevent the phenomenon of breaking by applying more power than one electrode end, it is possible to improve the durability, there is an advantage that it is easy to replace the plasma electrode 30 later.

In addition, the electrode of each stage is not particularly limited, and may be manufactured in various shapes, but in order to stably generate a plasma, it is preferable that the electrode is formed, and the diameter of the discharge part 31 positioned on the uppermost is shortest. It is preferable that the diameter of the grounding part 33 positioned at the bottom is the longest (see FIG. 4). By decreasing the diameter toward the top, the insulation efficiency and the discharge efficiency of the plasma electrode 30 can be improved. In order to maximize the insulation efficiency and the discharge efficiency of the plasma electrode 30, the ratio of the diameter d of the discharge part 31, the fixing part 32, and the ground part 33 is 1: 4 to 6: 7 to 8. It is preferable that the height h of the discharge part 31, the fixing part 32, and the ground part 33 is 1: 1: 1-2.

The plasma electrode may be installed separately in the reactor for water treatment, but may be installed in the reactor in the form of an electrode module in which a plurality of electrodes are disposed.

In an embodiment of the plasma electrode module 50, the plate shape of FIG. 5 (a) and the tube shape of FIG. 5 (b) are shown. The conductive base 52 and the holes in which a plurality of holes 51 are formed are provided. It may be composed of a ceramic layer 53 surrounding the outer periphery of the tungsten substrate.

Inside the hole, the above-described plasma electrode is located, the plasma electrode having a multi-stage structure in which the ground portion 33, the fixing portion 32 and the discharge portion 31 having a circumferential shape are sequentially stacked; The ground portion 33 is in contact with the conductive substrate, and plasma is generated in the discharge portion 31.

According to the shape of the conductive substrate may be implemented as a plate-shaped plasma electrode module and a tube-shaped plasma electrode module, it can be selectively used according to the shape of the water treatment reactor.

As the conductive substrate, a tungsten alloy material such as tungsten or tungsten nitride having high electrical conductivity and excellent durability is preferably used. The plasma electrode included in the plasma electrode module may include a ground part 33 and a fixing part 32. And the discharge portion 31 is preferably an integral structure made of the same material having corrosion resistance, the material having corrosion resistance while forming the integral structure is more preferably made of SUS material.

It is preferable that the ratio of the diameter of the ground part 33, the fixed part 32, and the discharge part 31 of the said plasma electrode is 7-8: 4-6: 1, The ground part 33 and the fixed part 32 ) And the height of the discharge portion 31 is preferably 1-2: 1: 1.

The conductive substrate may be in the form of a plate or cylinder, and tungsten material is preferably used.

Next, a water treatment system including a water treatment apparatus using plasma underwater discharge will be described. For convenience of description, the above-described water treatment apparatus 100 will be described as an example, and description of the overlapped portions will be omitted, but is not limited thereto.

6 shows a water treatment system 200 in which a water treatment apparatus according to an embodiment of the present invention is connected in series. Referring to FIG. 6, the water treatment system 200 according to an embodiment of the present invention includes a water treatment unit 110 for supplying water to be treated; And a plurality of water treatment apparatuses 100 connected in series and optionally a subsequent process tank 120 or a water treatment tank.

The water treatment apparatus 100 includes a reactor 10 having an inlet 11 through which the water to be treated is introduced and an outlet 12 through which the purified water is discharged; A ground electrode 20 provided at one side of the reactor 10; And a plasma electrode 30 provided at one side of the reactor 10 to generate plasma. A plurality of plasma electrodes 30 are typically used, and they may be located inside the reactor 10 in the form of a plasma electrode module 50.

The water treatment apparatus may use the water treatment apparatus 100 described above with reference to FIG. 1 or FIG. 2, and may sequentially process the water to be treated supplied from the water treatment unit 110 through the plurality of water treatment apparatuses 100. Can purify the water. In the case of the water treatment system 200 in which the water treatment apparatus 100 is connected in series, it is useful to purify the treated water having high pollution. That is, the organic matter and microorganisms in the water to be treated may be removed by performing plasma underwater discharge several times on the water to be treated which may cause bio fouling in a subsequent treatment process in which a large amount of organic matter and microorganisms are present therein.

7 is a water treatment system 300 connected in parallel with the water treatment apparatus according to an embodiment of the present invention. Referring to Figure 7, the water treatment system 300 according to an embodiment of the present invention is a water treatment unit 110 for supplying the water to be treated; And a plurality of water treatment devices 100 connected in parallel. And optionally a subsequent process tank 120 or a water treatment tank, wherein the water treatment apparatus 100 includes an inlet 11 through which the water to be treated flows in and an outlet 12 through which the purified water is discharged. A reactor 10; A ground electrode 20 provided at one side of the reactor 10; And a plasma electrode 30 provided at one side of the reactor 10 to generate plasma. A plurality of plasma electrodes 30 are typically used, and they may be located inside the reactor 10 in the form of a plasma electrode module 50.

The water treatment apparatus may use the water treatment apparatus 100 described above with reference to FIG. 1 or FIG. 2, while simultaneously supplying the water to be treated supplied from the water treatment unit 110 to the plurality of water treatment apparatuses 100 and simultaneously passing the treated water. The water to be treated can be purified. In the case of the water treatment system 300 in which the water treatment apparatuses 100 are connected in parallel, the pollution degree is not serious, but is useful for purifying a large amount of treated water.

EXAMPLE

In order to confirm the discharge characteristics according to the diameter of the discharge portion of the repair electrode plasma electrode according to an embodiment, the degree of generation of ozone (O3) by using the plasma electrode formed in the circumferential form of the ground portion, the fixed portion and the discharge portion It was.

After maintaining the lengths of the ground part, the fixing part, and the discharge part at 16 mm, 11 mm, and 11 mm, respectively, the concentration of ozone generated by applying current while changing the diameter of the discharge part in various ranges was measured. Ozone is generated by the plasma generated at the discharge end of the electrode, and this ozone has an important effect on the decomposition of contaminants such as reduction of TOC during plasma water treatment.

The diameter of the discharge portion was varied in the range of 1 to 4 mm, and the ratio of the diameters of the ground portion 33, the fixing portion 32 and the discharge portion 31 was kept constant at 7.5: 5: 1, and the same voltage The result of measuring the concentration of ozone produced by adding is shown in the table below.

Diameter of discharge part [mm] One 2 3 4 Generated O3 Concentration [ppm] - 0.06 0.07 0.0001

As shown in the results of Table 1, when the diameter of the discharge portion is too low, it can be seen that the generation of ozone is insignificant because the plasma is not formed properly, and when the diameter is too large, uniformly on the surface of the discharge portion It was confirmed that the amount of ozone generated as a whole was reduced because no plasma was generated.

In the present specification, only a few examples of various embodiments performed by the present inventors are described, but the technical idea of the present invention is not limited thereto, but may be variously modified and implemented by those skilled in the art.

10 reactor 11 inlet
12 outlet 20 20 electrode
30 plasma electrode 31 discharge part
32: fixing part 33: grounding part
40: distance control unit 50: plasma electrode module
100: water treatment device 110: treated water supply unit
200, 300: water treatment system

Claims (17)

It has a multi-stage structure in which the ground portion 33, the fixed portion 32 and the discharge portion 31, which have a circumferential shape, are sequentially stacked.
The ground portion 33 is in contact with the electrode, the plasma is generated in the discharge portion 31,
The ground portion 33, the fixing portion 32 and the discharge portion 31 has a single-piece structure of a cylinder made of SUS of the same material to have corrosion resistance, the diameter of the discharge portion 31 is located at the top, the shortest, The diameter of the ground portion 33 is located at the bottom is the longest,
The diameter of the discharge portion 31 is greater than 1mm, characterized in that less than 4mm, plasma electrode for water treatment. delete The method of claim 1,
The ratio of the diameters of the ground part 33, the fixing part 32 and the discharge part 31 is 7-8: 4-6: 1, characterized in that the plasma electrode for water treatment. The method of claim 1,
The ratio of the heights of the ground portion (33), the fixing portion (32) and the discharge portion (31) is 1 to 2: 1: 1, characterized in that the plasma electrode for water treatment. delete A tungsten substrate having a plurality of holes formed therein;
A ceramic layer surrounding the outer circumference of the tungsten base except for the hole; And
A plasma electrode having a multi-stage structure, which is located inside the hole and has a circumferential ground portion 33, a fixing portion 32, and a discharge portion 31 sequentially stacked;
The ground portion 33 is in contact with the tungsten substrate, the plasma is generated in the discharge portion 31,
The ground portion 33, the fixing portion 32 and the discharge portion 31 has a single-piece structure of a cylinder made of SUS of the same material to have corrosion resistance, the diameter of the discharge portion 31 located on the top is the shortest, The diameter of the ground portion 33 is located at the bottom is the longest,
The diameter of the discharge portion 31 is greater than 1mm, characterized in that less than 4mm, plasma electrode module for water treatment. delete The method of claim 6,
The ratio of the diameters of the ground portion (33), the fixing portion (32) and the discharge portion (31) is 7-8: 4-6: characterized in that the plasma electrode module for treatment. The method of claim 6,
The ratio of the heights of the ground portion (33), the fixing portion (32) and the discharge portion (31) is characterized in that 1 ~ 2: 1: 1, plasma electrode module for water treatment. delete The method of claim 6,
The tungsten substrate is in the form of a plate or columnar, plasma electrode module for water treatment. A reactor having an inlet through which the water to be treated is introduced and an outlet through which the purified water is discharged;
A ground electrode provided at one side of the reactor; And
Includes; is provided on one side of the reactor, the plasma electrode module for generating a plasma,
The plasma electrode module may include a tungsten base having a plurality of holes formed therein; A ceramic layer surrounding the outer circumference of the tungsten base except for the hole; And a plasma electrode positioned inside the hole and having a multi-stage structure in which a ground part 33 having a circumferential shape, a fixing part 32, and a discharge part 31 are sequentially stacked.
The ground portion 33 is in contact with the tungsten substrate, the plasma is generated in the discharge portion 31,
The ground portion 33, the fixing portion 32 and the discharge portion 31 has a single-piece structure of a cylinder made of SUS of the same material to have corrosion resistance, the diameter of the discharge portion 31 located on the top is the shortest, The diameter of the ground portion 33 is located at the bottom is the longest,
The diameter of the discharge portion 31 is greater than 1mm, characterized in that less than 4mm, water treatment apparatus The method of claim 12,
The reactor is characterized in that the inlet and outlet are provided on the same side, water treatment apparatus. The method of claim 12,
The reactor, characterized in that the inlet, outlet and ground electrode is provided on the same side, water treatment apparatus. The method of claim 12,
The reactor, characterized in that the ground electrode and the plasma electrode module is installed so as to face, water treatment apparatus. The method of claim 12,
The reactor, the water treatment device, characterized in that further provided; a distance adjusting unit for adjusting the distance between the ground electrode and the plasma electrode module. The method of claim 12,
The ground electrode is a water treatment device, characterized in that the plate shape.

Images