KR20150135158A - Apparatus for extracting and recovery metals from waste water - Google Patents

Abstract

The present invention provides a processing apparatus for extracting and collecting metals from waste water for extracting the metal from waste water by conducting electrochemical reduction, and collecting the extracted metal, comprising: a reaction tank which leads and stores waste water for an electrochemical reaction; an electrode which is arranged inside the reaction tank, and applies current to the waste water; and an ultrasonic vibrator which is respectively adhered to the electrode, and applies vibration to the electrode. According to the present invention, the apparatus can be used continuously without replacing the electrode, can improve extraction efficiency of the metal by increasing current supply efficiency to be applied into the waste water, and can reduce cost because the reactor can be configured as non-metallic materials.

Description

Technical Field [0001] The present invention relates to an apparatus for extracting and recovering metals from wastewater,

The present invention relates to an apparatus for extracting metal from wastewater and recovering the extracted metal. More particularly, the present invention relates to a wastewater containing metal, sludge containing solids or solids (hereinafter collectively referred to as "wastewater"), To an apparatus for extracting and recovering a metal from which a metal is extracted by performing electrochemical reduction, and the recovered metal is quickly desorbed and / or stripped to recover the metal.

Industrial wastewater, industrial sludge, bottom and sea dredged soil, metal contaminated soil, various incineration ash, and minerals in the production process of electronic products and metal processing contain various metals. These metals contain various metals Therefore, they are subject to emission control under the Waste Management Act and the Water and Aquaculture Conservation Act.

In addition, some of the metals contained in wastewater have high added value due to their scarcity, and therefore efforts are being made to recover and reuse wastewater or wastes.

Conventionally, a method of adding a coagulant to wastewater and recovering the metal as a sludge state has been widely used. However, since the precipitation method of coagulant administration not only increases the volume of contamination due to the occurrence of sludge, but also requires subsequent treatment of the generated sludge There is a problem that the cost is increased.

In order to solve the above problems, a treatment technique using electrolysis has been disclosed.

As a prior art related to the above-described electrolytic treatment technology, reference is made to Korean Patent No. 10-0231331 " Wastewater Treatment Method Using Electrolysis and Wastewater Treatment System ", after electrolysis of waste water in an electrolytic bath using a constant current , A polyacrylamide polymer flocculant is injected to form a floc having a large size and the remaining contaminants are completely electrolyzed in a secondary electrolytic cell by charging activated carbon and zeolite, It can be seen that the treated water is discharged.

In the electrolytic wastewater treatment technique, since a metal is attached to an electrode to which a current is applied, there is a problem that a process of separating the metal-attached electrode and then separating the metal from the electrode must be further performed. In addition, there is a problem that the electrode is damaged during the operation of separating the electrode and the metal, thereby shortening the replacement period of the electrode.

In order to solve the above problems, a technique has been disclosed in which ultrasonic waves are applied to an electrolytic cell in which electrolysis is performed to prevent metal from adhering to the electrode.

In order to increase the metal deposition prevention efficiency, the above-described technique has a problem in that the energy consumption increases because the output of the ultrasonic wave must be increased. In addition, since the electrolytic bath must be made of a metal material, the manufacturing cost is increased.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to improve the efficiency of supplying an applied current, thereby improving the extraction efficiency of metal from wastewater And an object of the present invention is to provide an apparatus for extracting and recovering a metal.

In order to accomplish the above object, an apparatus for extracting and recovering metal from wastewater according to the present invention is an apparatus for extracting metal from wastewater by performing electrochemical reduction and recovering the extracted metal, A reaction tank in which wastewater is introduced and stored; An electrode disposed inside the reaction tank and applying an electric current to the wastewater; And an ultrasonic vibrator attached to the electrodes to apply vibration to the electrodes.

The reaction tank may be made of one selected from the group consisting of metal, plastic, and composite materials, or an optional combination thereof.

The electrode may be in the form of a plate. Here, the electrode may be in the form of a perforated plate having a plurality of holes each having a diameter of 2 mm to 100 mm. Furthermore, the electrodes may include bent portions that are alternately changed in bending direction at regular intervals.

Alternatively, the electrode may be in the form of a bar. As an example, the electrode may be in the form of a rod having a diameter of 5 mm to 80 mm. In such a case, the ultrasonic vibrator may be disposed between the ends or both ends of the electrode.

As another alternative, the electrode may be in the form of a cylinder.

In addition, the electrode can be subjected to corrosion inhibition on the surface.

The ultrasonic transducer may also be enveloped by a corrosion-resistant material or a corrosion-resistant cover made of the same material as the electrode.

The apparatus for extracting and recovering the metal may further include a bubble generator disposed inside the reaction tank and generating bubbles with respect to the wastewater stored in the reaction tank.

The apparatus for extracting and recovering the metal may further include a circulation unit disposed inside the reaction tank and circulating the waste water stored in the reaction tank inside the reaction tank.

The apparatus for extracting and recovering metal from wastewater according to the present invention has the following effects.

First, the metal is reduced and extracted from the wastewater or slurry containing the metal by the electrochemical reduction reaction, and the electrode is directly vibrated by the ultrasonic vibrator attached to the electrode. At the same time, the ultrasonic wave is irradiated into the wastewater, The electrode can be continuously used without being replaced.

Second, by removing microorganisms or foreign substances coated on the electrode, the current supply efficiency applied to the wastewater can be increased, and the extraction efficiency of the metal can be increased accordingly.

Thirdly, in order to increase the vibration and ultrasonic transmission efficiency, the ultrasonic oscillation oscillator is installed on the bottom or side of the reactor. However, in the present invention, since the oscillator is directly attached to the metal electrode, It can be made of a non-metallic material such as plastic or glass fiber reinforced plastic, thus saving cost.

Fourth, by attaching the ultrasonic vibrator directly to the electrode, the transmission efficiency of the vibration is high, and therefore, high efficiency can be obtained even with a small output.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic view of a metal extraction and recovery apparatus according to a first embodiment of the present invention;
FIG. 2 is a view illustrating a connection state between the electrode and the ultrasonic vibrator shown in FIG. 1,
FIGS. 3 and 4 are views each showing a modification of the electrode shown in FIG. 1,
5 is a schematic view showing an apparatus for extracting and recovering a metal according to a second embodiment of the present invention,
FIG. 6 is a schematic view showing a metal extraction and recovery processing apparatus according to a third embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a schematic view illustrating an apparatus for extracting and recovering a metal according to a first embodiment of the present invention. FIG. 2 is a view illustrating a connection state between an electrode and an ultrasonic vibrator shown in FIG.

1 and 2, an apparatus 100 for extracting and processing a metal from wastewater according to a first embodiment of the present invention includes a reaction tank 110, an electrode (not shown) 120, and an ultrasonic transducer 130. The apparatus 100 for extracting and processing a metal may further include a bubble generator 140 and a circulation unit 150.

First, an apparatus 100 for extracting and processing a metal according to the present invention is characterized in that an electric current is applied to wastewater, and an applied electric current is an electrolytic apparatus for reducing ion metal contained in wastewater to metal to precipitate as metal Include basically. Such an electrolytic apparatus is a well-known technique widely known in the art to which the present invention belongs, and therefore, a detailed description thereof will be omitted.

The reaction vessel 110 receives, for example, wastewater generated in a production process of an electronic product or a metal processing process, and is temporarily stored. The wastewater, which has been inflowed and stored as described above, undergoes an electrochemical reaction in the reaction tank 110. The reaction tank 110 is manufactured to have a predetermined size according to need, and an inlet pipe 112 for introducing the waste water and an outlet pipe 114 for discharging the treated waste water are connected. In FIG. 1, the reaction vessel 110 has a rectangular shape. However, the reaction vessel 110 is illustrative and various shapes including a cylindrical shape can be applied as needed.

Meanwhile, in the present invention, the reaction vessel 110 may be made of various materials. For example, the reaction vessel 110 may be manufactured using a conductive metal as in the conventional art, but may be made of plastic or a composite material (glass fiber, carbon fiber, or the like) which is a less expensive material. Also, the reaction vessel 110 may be manufactured by selectively combining metal, plastic, and composite materials. The reason for this will be described later. Further, the reaction vessels 110 may be arranged in a single unit, but a plurality of reaction vessels 110 may be arranged in such a manner that the wastewater can be circulated.

The electrode 120 may be disposed inside the reaction tank 110 to apply a current to the waste water stored in the reaction tank 110. The electrode 120 may include a positive electrode and a negative electrode. The number and arrangement of the electrodes 120 may be variously set as needed.

The electrode 120 may have various shapes such as a rectangular shape or a circular shape as a plate shape as shown in FIGS. 1 and 2. In one embodiment, the electrode 120 may be in the form of a perforated plate having a plurality of holes 122 formed therethrough. At this time, the diameter of the hole 122 is preferably 2 mm to 100 mm.

The width of the electrode 120 may be smaller than the inner width of the reaction tank 110 so as to prevent the circulation of the wastewater in the reaction tank 110. In order to prevent the surface of the electrode 120 from being corroded by the substances contained in the wastewater, the surface of the electrode 120 may be treated with corrosion.

Meanwhile, the electrodes 120 (120A, 120B) may have various modifications as shown in FIGS. 3 and 4 in order to expand the contact area with the wastewater. That is, as shown in FIG. 3, the electrode 120A may include a bent portion having a plate shape and a bending direction changing at regular intervals. In addition, like the electrode 120B shown in Fig. 4, the bending direction may be changed while changing the bending direction.

The ultrasonic transducer 130 is directly attached to the electrode 120 to apply ultrasonic waves to the electrode 120 to prevent the metal from adhering to the electrode 120 or to remove the attached metal. At this time, the ultrasonic wave applied to the electrode 120 from the ultrasonic transducer 130 can be directly generated from the ultrasonic transducer 130, but it is also possible to dispose an ultrasonic oscillator 132 on the outside, And may be configured to be applied to the electrode 120 after being transmitted to the ultrasonic transducer 130.

In more detail, the ultrasonic transducer 130 generates ultrasonic waves in the range of 10 kHz to 80 kHz and applies the generated ultrasonic waves to the electrode 120. The ultrasonic wave vibrates the electrode 120 to prevent the metal separated from the foreign matter and the wastewater from adhering to the electrode 120. Further, the metal particles already attached to the electrode 120 can be desorbed by the vibration of the electrode.

Ultrasonic waves applied to the electrode 120 in the ultrasonic vibrator 130 are transmitted to the wastewater in the reaction tank 110 after vibrating the electrode 120. The wastewater that receives ultrasonic waves is cavitated. The water molecules of the wastewater are accelerated and hit against the cathode and the anode, and the metal and foreign matter adhered to the electrode are removed by the impact generated at this time. The metal thus desorbed can be precipitated by gravity. Further, the desorbed metal can be withdrawn as a solution in which the metal is mixed.

Here, the frequency of the ultrasonic waves generated in the ultrasonic vibrator 130 is 10 kHz to 80 kHz. However, when the size of the metal particles precipitated from the electrode 120 is large, By using the frequency, the desorption effect can be improved.

The ultrasonic vibrator 130 as described above may be enveloped by the anti-corrosion cover 134 to prevent corrosion. Here, the corrosion-preventing cover 134 is preferably made of a corrosion-resistant material such as plastic or the like and a metal material similar to the electrode.

As described above, according to the embodiment of the present invention, the electrode 120 is directly vibrated by the ultrasonic vibrator 130 attached to the electrode 120 and the ultrasonic wave is radiated into the wastewater, The electrode 120 can be continuously used without being replaced.

Also, by removing microorganisms or foreign substances coated on the electrode 120, the current supply efficiency applied to the wastewater can be increased, and the metal extraction efficiency can be increased accordingly.

In order to increase the vibration and ultrasonic wave transmission efficiency, the reaction tank must be made of a metal material. However, in the present invention, the ultrasonic vibrator 130 is directly attached to the metal electrode 120 So that the material of the reaction tank 110 can be made of a non-metallic material such as plastic or glass fiber reinforced plastic, thereby reducing the cost.

In the embodiment of the present invention as described above, the bubble generating unit 140 and the circulation unit 150 may be disposed further inside the reaction tank 110.

The bubble generator 140 generates bubbles to the wastewater stored in the reaction tank 110. To this end, the bubble generator 140 includes a nozzle 142 that can receive an external gas and discharge the same in a predetermined amount. Here, the degree of discharge of the gas through the nozzle 142 can be changed as needed. Here, the gas discharge level can be controlled by various methods such as adjusting the operation amount of an external gas pump (not shown) or controlling the diameter of the nozzle 142.

The circulation unit 150 generates a flow in the waste water stored in the reaction tank 110 so that the waste water circulates in the reaction tank 110 and can be continuously contacted with the electrode 120.

Hereinafter, an apparatus for extracting and recovering a metal according to a second embodiment of the present invention will be described. 5 is a schematic view showing an apparatus 200 for extracting and recovering a metal according to a second embodiment of the present invention. Here, the same components as those in the first embodiment will not be described in detail, and only differences will be described. The same reference numerals as those shown in Figs. 1 to 4 denote the same members having the same constitution and operation effect, and thus, repetitive description will be omitted.

In the metal extraction and recovery apparatus 200 according to the second embodiment of the present invention, the electrode 220 to be used has a shape of a bar. In one embodiment, the electrode 220 may have a circular cross-section as shown in FIG. 5, but the present invention is not limited thereto. For example, the end face of the electrode 220 may have a polygonal shape including a rectangular shape. Further, if the length of the electrode 220 is relatively long, an electrode having an amorphous shape may be used.

When the electrode 220 has a circular cross-section as shown in FIG. 5, the diameter of the rod is preferably 5 to 80 mm. The ultrasonic transducer 230 is attached between the end of the electrode 220 or between the upper end and the lower end of the electrode 220 and the ultrasonic wave is applied to the electrode 220 to prevent metal from adhering to the electrode 220, So that the deposited metal is desorbed. It is preferable that the ultrasonic vibrator 230 is submerged in the wastewater.

5, the number of the electrodes 220 is six. However, the number of the electrodes 220 is not limited thereto, and may be increased or decreased as needed. In addition, although the bar-shaped electrode 220 is shown as being fixed at its lower end, its upper end may be fixed.

Hereinafter, an apparatus for extracting and recovering a metal according to a third embodiment of the present invention will be described. FIG. 6 is a schematic view showing an apparatus 300 for extracting and recovering a metal according to the third embodiment of the present invention. Here, the same components as those of the first and second embodiments will not be described in detail, and only differences will be described. In addition, the same reference numerals as those shown in Figs. 1 to 5 denote the same members having the same constitution and operation effect, and thus a repetitive description thereof will be omitted.

In the metal extraction and recovery apparatus 300 according to the third embodiment of the present invention, the electrode 320 to be used is a cylindrical shape having a predetermined length and diameter. Here, the length and the diameter of the electrode 320 may be variously set according to needs. At this time, both ends of the electrode 320 can be opened or closed depending on the purpose. At this time, the ultrasonic transducer 330 is attached on the inner circumferential surface or the outer circumferential surface of the electrode 320, and ultrasonic waves are applied to the electrode 320 to prevent foreign substances and metal from adhering to the electrode or to allow the attached metal to be removed.

On the other hand, although the number of the electrodes 320 is two in FIG. 6, the number of the electrodes 320 is not limited to two, and may be increased or decreased as needed.

While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. Accordingly, the true scope of the present invention should be determined by the technical idea of the appended claims.

100, 200, 300: Metal extraction and recovery device
110, 210, 310: Reactor
120, 220, 320: electrode
130, 230, 330: Ultrasonic vibrator
140, 240, 340: bubble generator
150, 250, 350:

Claims (13)

Electrochemical reduction to extract the metal from the wastewater and to recover the extracted metal,
A reaction tank in which wastewater for electrochemical reaction is stored;
An electrode disposed inside the reaction tank and applying an electric current to the wastewater; And
And an ultrasonic vibrator attached to each of the electrodes to apply vibration to the electrode. The method according to claim 1,
Wherein the reaction tank is made of one selected from the group consisting of metal, plastic and composite materials or an optional combination thereof. The method according to claim 1,
Wherein the electrode is a plate-shaped wastewater. The method of claim 3,
Wherein the electrode is a porous plate having a plurality of holes each having a diameter of 2 mm to 100 mm. The method of claim 3,
Wherein the electrode includes a bending portion whose bending direction is alternately changed at regular intervals. The method according to claim 1,
The electrode is a device for extracting and recovering metal from wastewater in the form of a bar. The method of claim 6,
Wherein the electrode is a rod having a diameter of 5 to 80 mm. The method according to claim 6,
Wherein the ultrasonic vibrator is disposed between the ends or both ends of the electrode. The method according to claim 1,
Wherein the electrode is a cylindrical shape. The method according to any one of claims 1 to 9,
Wherein the electrode is subjected to a corrosion inhibiting treatment on the surface thereof. The method according to any one of claims 1 to 9,
Wherein the ultrasonic transducer is enveloped by a corrosion-resistant material or an anti-corrosion cover made of the same material as the electrode. The method according to claim 1,
And a bubble generator disposed inside the reaction tank and generating bubbles with respect to the wastewater stored in the reaction tank. The method according to claim 1 or 12,
And a circulation unit arranged inside the reaction tank and circulating the wastewater stored in the reaction tank inside the reaction tank.

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