Electrochemical remediation device for heavy metal soil

Abstract

The utility model discloses an electrochemical remediation device for heavy metal soil, which relates to the technical field of soil remediation and comprises a plurality of electrode cones arranged in the soil in an array, and the adjacent electrode cones are respectively connected with different electrodes of a power supply; the electrode cone comprises an inverted-cone-shaped porous shell, an inverted-cone-shaped filtering layer and an inverted-cone-shaped conductive porous fiber electrode; the inverted-cone-shaped filtering layer is placed on the inner side of the inverted-cone-shaped porous shell, and the inverted-cone-shaped conductive porous fiber electrode is placed on the inner side of the inverted-cone-shaped filtering layer. By arranging the inverted-cone-shaped electrode cone structure and combining the inverted-cone-shaped conductive porous fiber electrode, soil in-situ remediation is achieved on the premise that the electrode polarization phenomenon is reduced; the electrode cones are arranged in an array mode, and the adjacent electrode cones are connected with different electrodes of the power source respectively, so that the soil remediation effect and remediation uniformity are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of soil remediation, in particular to a heavy metal soil electrochemical remediation device. BACKGROUND

[0002] Soil heavy metal pollution is one of the most common ecological environmental problems in global land distribution. At present, the electrochemical remediation method can move the heavy metal ions in the soil to the vicinity of the electrode under the combined action of electromigration, electrodialysis and electrophoresis, so as to enrich the pollutants in the electrode area and achieve the purpose of recycling or removing the pollution, but this method will have electrode polarization phenomenon, which will affect the subsequent reaction.

[0003] In the prior art, Chinese patent CN207343449U discloses a device for electrochemically remediation of heavy metal contaminated soil, which is sequentially provided with a soil area, a sand layer area and an electrode area from inside to outside. The soil area and the sand layer area are separated by a filter membrane, and the sand layer area and the electrode area are separated by a filter membrane. The electrode area is divided into a first electrode area and a second electrode area by an insulating area, and the first electrode area and the second electrode area are provided with electrodes. The device uses replaceable conductive porous fiber modified electrodes to reduce the polarization phenomenon.

[0004] However, the above prior art needs to specially set up a soil area, and the soil to be remediated is filled into the soil area for remediation, which cannot realize in-situ remediation of the soil under the premise of reducing the electrode polarization phenomenon. In addition, the electrode area of the above prior art is located on both sides of the soil area, and the remediation effect of the soil to be remediated in the middle of the soil area is poor, and thus the remediation uniformity is poor. CONTENT OF THE UTILITY MODEL

[0005] The present application provides a heavy metal soil electrochemical remediation device to solve the problem that the prior art cannot realize in-situ remediation of the soil under the premise of reducing the electrode polarization phenomenon, and the soil remediation effect and remediation uniformity are poor.

[0006] In one aspect, the present application provides a heavy metal soil electrochemical remediation device, comprising: a plurality of electrode cones arranged in an array in the soil, and adjacent electrode cones are respectively connected to different poles of a power supply.

[0007] The electrode cone comprises: an inverted conical porous shell, an inverted conical filter layer and an inverted conical conductive porous fiber electrode.

[0008] The inverted conical filter layer is placed inside the inverted conical porous shell, and the inverted conical conductive porous fiber electrode is placed inside the inverted conical filter layer.

[0009] In one possible implementation, the inverted conical porous shell is made of organic glass material or stainless steel material with penetration holes.

[0010] In a possible implementation, the inverted-cone-shaped filter layer comprises an inverted-cone-shaped filter layer framework and a filter membrane wrapped outside the inverted-cone-shaped filter layer framework.

[0011] In a possible implementation, the inverted-cone-shaped conductive porous fiber electrode comprises an inverted-cone-shaped electrode framework and a conductive porous fiber wrapped outside the inverted-cone-shaped electrode framework.

[0012] In a possible implementation, the inverted-cone-shaped electrode framework adopts a graphite electrode.

[0013] In a possible implementation, the inverted-cone-shaped porous shell, the inverted-cone-shaped filter layer, and the inverted-cone-shaped conductive porous fiber electrode are all in the shape of an inverted circular cone or an inverted multi-prism cone.

[0014] In a possible implementation, a humidity sensor and a water injector are arranged in the soil between the electrode cones.

[0015] In a possible implementation, a neutral salt solution is injected into the electrode cones.

[0016] The heavy metal soil electrochemical remediation device has the following advantages:

[0017] By arranging the electrode cone structure in the shape of an inverted cone and combining the replaceable inverted-cone-shaped conductive porous fiber electrode, the soil in-situ remediation is realized under the premise of reducing the electrode polarization phenomenon; by arranging the electrode cone array, the adjacent electrode cones are connected to different poles of the power supply, thereby improving the soil remediation effect and remediation uniformity.

[0018] The proposed inverted-cone-shaped conductive porous fiber electrode comprises an inverted-cone-shaped electrode framework and a conductive porous fiber wrapped outside the inverted-cone-shaped electrode framework, which increases the surface area of the electrode and further improves the adsorption effect on heavy metal ions.

[0019] The proposed arrangement of a humidity sensor and a water injector in the soil between the electrode cones can improve the migration rate of heavy metal ions by adjusting the water content of the soil, thereby improving the soil remediation efficiency. DETAILED DESCRIPTION

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed in the embodiment or prior art description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0021] Fig. 1A front cross-sectional view of the electrode cone provided in an embodiment of this application;

[0022] Fig. 2 A top cross-sectional view of the electrode cone provided in an embodiment of this application;

[0023] Fig. 3 This is a schematic diagram of the electrode cone polarity arrangement of an electrochemical remediation device for heavy metal soil provided in an embodiment of this application.

[0024] Explanation of reference numerals in the attached figures:

[0025] 1-Electrode cone, 11-Inverted conical porous shell, 12-Inverted conical filter layer, 13-Inverted conical conductive porous fiber electrode, 14-Neutral salt solution. Detailed Implementation

[0026] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0027] like Figs. 1 to 3 As shown in the figure, this application provides a heavy metal soil electrochemical remediation device, including: a plurality of electrode cones 1 arranged in an array in the soil, with adjacent electrode cones 1 respectively connected to different poles of a power source.

[0028] The electrode cone 1 includes: an inverted cone-shaped porous outer shell 11, an inverted cone-shaped filter layer 12, and an inverted cone-shaped conductive porous fiber electrode 13.

[0029] The inverted conical filter layer 12 is placed inside the inverted conical porous outer shell 11, and the inverted conical conductive porous fiber electrode 13 is placed inside the inverted conical filter layer 12.

[0030] Specifically, in this embodiment, sixteen electrode cones 1 are arranged in a four-row, four-column array. By connecting adjacent electrode cones 1 to different poles of the power supply, the polarities of adjacent electrode cones 1 are different, thereby shortening the migration distance of heavy metal ions and improving the soil remediation effect. Simultaneously, the arrayed arrangement of electrode cones 1 also improves the uniformity of remediation. In other possible embodiments, other numbers of electrode cones 1 can be used depending on the size of the area of ​​soil to be remediated.

[0031] For example, the inverted conical porous shell 11 is made of plexiglass or stainless steel with permeable pores.

[0032] Specifically, in the present embodiment, the inverted conical porous shell 11 is made of organic glass material.

[0033] In one possible embodiment, the top of the inverted conical porous shell 11 is provided with a cover plate made of the same material as the inverted conical porous shell 11.

[0034] Exemplarily, the inverted conical filter layer 12 comprises an inverted conical filter layer framework and a filter membrane wrapped outside the inverted conical filter layer framework.

[0035] Specifically, in the present embodiment, the inverted conical filter layer framework is made of stainless steel framework, and in other possible embodiments, it can also be made of plastic framework; in the present embodiment, the filter membrane is made of polyvinylidene fluoride filter membrane, and in other possible embodiments, it can also be made of ceramic filter membrane, polytetrafluoroethylene filter membrane or geotextile.

[0036] Exemplarily, the inverted conical conductive porous fiber electrode 13 comprises an inverted conical electrode framework and a conductive porous fiber wrapped outside the inverted conical electrode framework.

[0037] Specifically, the conductive porous fiber in the present embodiment is the conductive porous fiber in Chinese patent CN207343449U (a device for electrically repairing heavy metal contaminated soil).

[0038] Exemplarily, the inverted conical electrode framework is made of graphite electrode.

[0039] Exemplarily, the shapes of the inverted conical porous shell 11, the inverted conical filter layer 12 and the inverted conical conductive porous fiber electrode 13 are all inverted conical or inverted multi-prism conical.

[0040] Specifically, in the present embodiment, the inverted conical porous shell 11, the inverted conical filter layer 12 and the inverted conical conductive porous fiber electrode 13 all adopt inverted conical structure, and in other possible embodiments, they can also adopt inverted triangular prism, inverted quadrangular prism and other inverted multi-prism conical structures.

[0041] Exemplarily, a humidity sensor and a water injector are arranged in the soil between the electrode cones 1.

[0042] Specifically, the humidity sensor and the water injector are both electrically connected with a water injection control unit, and the water injection control unit is connected with a power supply; in the present embodiment, during the process of soil remediation, when the humidity sensor monitors that the soil humidity is lower than the preset humidity threshold value (the humidity threshold value is set to 30% in the present embodiment), the water injection control unit controls the corresponding water injector to inject water into the soil, so as to ensure that the soil moisture content meets the demand of the migration rate of heavy metal ions.

[0043] Exemplarily, the electrode cone 1 is injected with a neutral salt solution 14.

[0044] Specifically, in the present embodiment, the neutral salt solution 14 is a sodium citrate solution with a concentration of 0.1 mol / L, and in other possible embodiments, a sodium nitrate solution or other neutral salt solution 14 can also be used.

[0045] Specifically, in the present embodiment, the method for using the heavy metal soil electrochemical remediation device is as follows:

[0046] Sixteen inverted conical electrode cones 1 are arranged in an array of four rows and four columns and inserted into the soil to be remediated; 0.1 mol / L sodium citrate solution is injected into each electrode cone 1; adjacent electrode cones 1 are respectively connected to different poles of the power supply, and heavy metal ions in the soil migrate to the nearest electrode cone 1 with a cathode polarity, sequentially pass through the corresponding inverted conical porous shell 11 and inverted conical filter layer 12, and deposit on the corresponding inverted conical conductive porous fiber electrode 13 to form metal elements, and at the same time, the sodium citrate solution also plays a role in assisting the collection of heavy metal ions; every thirty minutes, the inverted conical conductive porous fiber electrode 13 of the electrode cone 1 with a cathode polarity is replaced with a new one, and the sodium citrate solution in each electrode cone 1 is also replaced. In other possible embodiments, the polarity of all electrode cones 1 can also be switched after the new inverted conical conductive porous fiber electrode 13 is replaced.

[0047] The present application arranges the inverted conical electrode cone 1 structure and combines the replaceable inverted conical conductive porous fiber electrode 13 to achieve in-situ soil remediation under the premise of reducing electrode polarization; by arranging the array of electrode cones 1, adjacent electrode cones 1 are respectively connected to different poles of the power supply, thereby improving the soil remediation effect and remediation uniformity.

[0048] The proposed inverted conical conductive porous fiber electrode 13 includes an inverted conical electrode skeleton and conductive porous fibers wrapped outside the inverted conical electrode skeleton, which improves the surface area of the electrode and further improves the adsorption effect on heavy metal ions.

[0049] The proposed wetness sensor and water injector arranged in the soil between the several electrode cones 1 can improve the migration rate of heavy metal ions by adjusting the water content of the soil, thereby improving the soil remediation efficiency.

[0050] Although the preferred embodiments of the present application have been described, those skilled in the art can make additional changes and modifications to these embodiments once they know the basic inventive concept. Therefore, the appended claims are intended to be interpreted as including all changes and modifications falling within the scope of the present application.

[0051] Obviously, many modifications and variations of the present application are possible in light of the above teachings. It is, therefore, to be understood that within the scope of the appended claims and their equivalents, the application can be practiced otherwise than as specifically described.

Claims

1. An apparatus for electrochemically remediating heavy metal contaminated soil, comprising: The application relates to a soil moisture sensor. The soil moisture sensor comprises a plurality of electrode cones arranged in soil, and adjacent electrode cones are connected with different poles of a power supply respectively. The electrode cone comprises an inverted-cone-shaped porous shell, an inverted-cone-shaped filter layer and an inverted-cone-shaped conductive porous fiber electrode. The inverted-cone-shaped filter layer is arranged on the inner side of the inverted-cone-shaped porous shell, and the inverted-cone-shaped conductive porous fiber electrode is arranged on the inner side of the inverted-cone-shaped filter layer.

2. The apparatus for electrochemically remediating heavy metals in soil according to claim 1, wherein, The inverted-cone-shaped porous shell is made of organic glass material or stainless steel material with permeation holes.

3. The apparatus for electrochemically remediating heavy metals in soil according to claim 1, wherein The inverted-cone-shaped filter layer comprises an inverted-cone-shaped filter layer framework and a filter film wrapped on the outer side of the inverted-cone-shaped filter layer framework.

4. The apparatus for electrochemically remediating heavy metals in soil of claim 1, wherein, The inverted-cone-shaped conductive porous fiber electrode comprises an inverted-cone-shaped electrode framework and conductive porous fiber wrapped on the outer side of the inverted-cone-shaped electrode framework.

5. An apparatus for electrochemically remediating heavy metals in soil according to claim 4, wherein The inverted-cone-shaped electrode framework is made of graphite electrode.

6. The apparatus of claim 1, wherein the apparatus is configured to be placed in the ground such that the anode and the cathode are positioned on opposite sides of the soil to be treated. The inverted-cone-shaped porous shell, the inverted-cone-shaped filter layer and the inverted-cone-shaped conductive porous fiber electrode are all in the shape of inverted-cone or inverted multi-prism cone.

7. The apparatus of claim 1, wherein the apparatus is configured to be placed in the ground such that the anode and the cathode are positioned on opposite sides of the soil to be treated. A humidity sensor and a water injector are arranged in the soil between the plurality of electrode cones.

8. The apparatus for electrochemically remediating heavy metals in soil of claim 1, wherein, A neutral salt solution is injected into the electrode cone.

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