Particle electrode for soil remediation and application thereof

Abstract

The invention discloses a particle electrode for soil remediation and application of the particle electrode. The particle electrode is prepared from waste powdered ink, biomass charcoal powder, graphite fibers, dolomite powder, fly ash, steel slag micro powder, clay powder, a foaming agent, a stabilizer and a dispersing agent. The application comprises the following steps: step 1, weighing raw materials; 2, mixing the raw materials; step 3, compression molding; step 4, high-temperature calcination; 5, soil remediation; according to the invention, biomass charcoal powder is added into the formula, so that the particle electrode has a microporous structure, and foaming treatment is combined, so that the specific surface area of the particle electrode is increased, and therefore, the soil remediation efficiency is improved; the electrode has excellent conductivity and corrosion resistance, most of the formula components adopt waste materials, waste utilization is achieved, and compared with an existing metal electrode, the electrode has the advantages of being high in soil remediation efficiency, low in cost and long in service life.

Description

Technical Field

[0001] The present invention relates to the technical field of soil remediation, and in particular to a particle electrode for soil remediation and application thereof. Background Art

[0002] Soil electroremediation technology is a remediation method that uses electric fields to remove pollutants from the soil. The basic principle is to insert electrodes into the contaminated soil and pass direct current. The pollutants in the soil are brought to both ends of the electrodes under the action of electrokinetic processes such as electromigration, electrodialysis and electrophoresis generated by the electric field, thereby cleaning the contaminated soil. The anode electrodes used in existing soil electroremediation generally use graphite electrodes, and the cathode electrodes use ordinary metal electrodes. However, the specific surface area of ​​existing metal electrodes is small, resulting in low soil remediation efficiency; and the cost of metal electrodes is high, resulting in increased soil remediation costs; at the same time, due to the poor corrosion resistance of metal electrodes, their service life is short, so the electrodes need to be replaced frequently, which further increases the cost of soil remediation. Summary of the invention

[0003] The object of the present invention is to provide a particle electrode for soil remediation and its application to solve the problems raised in the above background technology.

[0004] To achieve the above-mentioned purpose, the present invention provides the following technical scheme: a particle electrode for soil remediation, the formula of which includes: waste toner, biomass carbon powder, graphite fiber, dolomite powder, fly ash, steel slag powder, clay powder, foaming agent, stabilizer and dispersant, and the mass percentage content of each component is: 13-17% of waste toner, 40-50% of biomass carbon powder, 2-4% of graphite fiber, 5-7% of dolomite powder, 5-7% of fly ash, 10-14% of steel slag powder, 8-12% of clay powder, 0.5-1.5% of foaming agent, 0.5-1.5% of stabilizer and 0.5-1.5% of dispersant.

[0005] Preferably, the mass percentage contents of the components are: 15% waste toner, 45% biomass carbon powder, 3% graphite fiber, 6% dolomite powder, 6% fly ash, 12% steel slag powder, 10% clay powder, 1% foaming agent, 1% stabilizer and 1% dispersant.

[0006] Preferably, the biomass charcoal powder is one or more of straw charcoal, wood charcoal, rice husk charcoal, fruit shell charcoal and bamboo charcoal.

[0007] Preferably, the foaming agent is one or more of sodium bicarbonate, ammonium bicarbonate, and azodicarbonamide.

[0008] Preferably, the stabilizer is sodium carboxymethyl cellulose.

[0009] Preferably, the dispersant is one or more of sodium dodecyl sulfate, polyacrylic acid, and sodium lignin sulfonate.

[0010] An application of a particle electrode for soil remediation, comprising step 1, weighing raw materials; step 2, mixing raw materials; step 3, pressing and forming; step 4, high-temperature calcination; step 5, soil remediation;

[0011] In the above step 1, the sum of the mass percentages of the components is taken as 1, and the raw materials are weighed according to the particle electrode formula ratio;

[0012] In the above step 2, the raw materials weighed in step 1 are placed in a stirring tank, water is added and mixed evenly to obtain a mixture;

[0013] In the above step 3, the mixture obtained in step 2 is pressed into shape using a mold to obtain an electrode blank, which is dried for standby use; wherein a terminal is pre-embedded in the electrode blank;

[0014] In the above step 4, the electrode blank dried in step 3 is placed in a high temperature furnace for calcination, and after calcination, it is cooled to room temperature to obtain a particle electrode;

[0015] In the above step 5, the particle electrode obtained in step 4 is used as the cathode electrode of the soil electric remediation device, and the graphite electrode is used as the anode electrode, and the soil electric remediation device is used to remediate the soil to be remediated.

[0016] Preferably, in step 2, the ratio of raw materials to water is 3-4:1.

[0017] Preferably, in step 4, the calcination treatment adopts staged calcination, specifically: first preheating at 200-600°C for 20-40min, then gradually heating to 700-1000°C, and the calcination time is 2-3h.

[0018] Preferably, in step five, the soil to be repaired is repaired using the soil electric repair device as follows: the soil to be repaired is placed in the soil chamber of the reaction tank, the anode electrode is placed in the anode chamber, the cathode electrode is placed in the cathode chamber, and an electrolyte is injected into the soil chamber until the electrolyte submerges the soil to be repaired, and finally the anode electrode and the cathode electrode are electrically connected to a DC power supply to repair the soil to be repaired.

[0019] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention adds biomass carbon powder to the formula so that the particle electrode has a microporous structure, and combines with foaming treatment to increase the specific surface area of ​​the particle electrode, thereby improving the soil remediation efficiency; by adding waste toner, graphite fiber, dolomite powder and steel slag powder to the formula, the electrode has excellent conductivity and corrosion resistance at the same time, and the formula ingredients are mostly waste materials, realizing waste utilization, and compared with the existing metal electrodes, it has the advantages of high soil remediation efficiency, low cost and long service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is an application flow chart of the present invention;

[0021] Figure 2 It is a schematic diagram of the front cutaway structure of the soil electric repair device of the present invention.

[0022] In the figure: 1. Soil electric remediation device; 11. DC power supply; 12. Anode electrode; 13. Cathode electrode; 14. Reaction cell; 15. Soil chamber; 16. Soil to be remediated; 17. Electrolyte; 18. Anode chamber; 19. Cathode chamber. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] Please see attached Figure 1 -Attached Figure 2 , a technical solution provided by the present invention:

[0025] Embodiment 1:

[0026] A particle electrode for soil remediation, comprising: waste toner, biomass carbon powder, graphite fiber, dolomite powder, fly ash, steel slag powder, clay powder, foaming agent, stabilizer and dispersant, wherein the mass percentage content of each component is: 15% of waste toner, 45% of biomass carbon powder, 3% of graphite fiber, 6% of dolomite powder, 6% of fly ash, 12% of steel slag powder, 10% of clay powder, 1% of foaming agent, 1% of stabilizer and 1% of dispersant, the biomass carbon powder is straw charcoal, the foaming agent is sodium bicarbonate, the stabilizer is sodium carboxymethyl cellulose, and the dispersant is sodium dodecyl sulfate.

[0027] An application of a particle electrode for soil remediation, comprising step 1, weighing raw materials; step 2, mixing raw materials; step 3, pressing and forming; step 4, high-temperature calcination; step 5, soil remediation;

[0028] In the above step 1, the sum of the mass percentages of the components is taken as 1, and the raw materials are weighed according to the particle electrode formula ratio;

[0029] In the above step 2, the raw materials weighed in step 1 are placed in a stirring tank, and water is added and mixed to obtain a mixture; wherein the ratio of the raw materials to water is 3-4:1;

[0030] In the above step 3, the mixture obtained in step 2 is pressed into shape using a mold to obtain an electrode blank, which is dried for standby use; wherein a terminal is pre-embedded in the electrode blank;

[0031] In the above step 4, the electrode blank dried in step 3 is placed in a high temperature furnace for calcination, and after calcination, it is cooled to room temperature to obtain a particle electrode; wherein the calcination is performed by staged calcination, specifically: first preheating at 200-600°C for 20-40min, then gradually heating to 700-1000°C, and the calcination time is 2-3h;

[0032] In the above step five, the particle electrode obtained in step four is used as the cathode electrode 13 of the soil electric remediation device 1, and the graphite electrode is used as the anode electrode 12. The soil electric remediation device 1 is used to repair the soil 16 to be repaired. Specifically, the soil 16 to be repaired is placed in the soil chamber 15 of the reaction tank 14, the anode electrode 12 is placed in the anode chamber 18, the cathode electrode 13 is placed in the cathode chamber 19, and the electrolyte 17 is injected into the soil chamber 15 until the electrolyte 17 submerges the soil 16 to be repaired. Finally, the anode electrode 12 and the cathode electrode 13 are electrically connected to the DC power supply 11 to repair the soil 16 to be repaired.

[0033] Embodiment 2:

[0034] A particle electrode for soil remediation, comprising: waste toner, biomass carbon powder, graphite fiber, dolomite powder, fly ash, steel slag powder, clay powder, foaming agent, stabilizer and dispersant, wherein the mass percentage content of each component is: 13% of waste toner, 50% of biomass carbon powder, 4% of graphite fiber, 5% of dolomite powder, 7% of fly ash, 10% of steel slag powder, 8% of clay powder, 1% of foaming agent, 1% of stabilizer and 1% of dispersant, the biomass carbon powder is straw charcoal, the foaming agent is sodium bicarbonate, the stabilizer is sodium carboxymethyl cellulose, and the dispersant is sodium dodecyl sulfate.

[0035] An application of a particle electrode for soil remediation, comprising step 1, weighing raw materials; step 2, mixing raw materials; step 3, pressing and forming; step 4, high-temperature calcination; step 5, soil remediation;

[0036] In the above step 1, the sum of the mass percentages of the components is taken as 1, and the raw materials are weighed according to the particle electrode formula ratio;

[0037] In the above step 2, the raw materials weighed in step 1 are placed in a stirring tank, and water is added and mixed to obtain a mixture; wherein the ratio of the raw materials to water is 3-4:1;

[0038] In the above step 3, the mixture obtained in step 2 is pressed into shape using a mold to obtain an electrode blank, which is dried for standby use; wherein a terminal is pre-embedded in the electrode blank;

[0039] In the above step 4, the electrode blank dried in step 3 is placed in a high temperature furnace for calcination, and after calcination, it is cooled to room temperature to obtain a particle electrode; wherein the calcination is performed by staged calcination, specifically: first preheating at 200-600°C for 20-40min, then gradually heating to 700-1000°C, and the calcination time is 2-3h;

[0040] In the above step five, the particle electrode obtained in step four is used as the cathode electrode 13 of the soil electric remediation device 1, and the graphite electrode is used as the anode electrode 12. The soil electric remediation device 1 is used to repair the soil 16 to be repaired. Specifically, the soil 16 to be repaired is placed in the soil chamber 15 of the reaction tank 14, the anode electrode 12 is placed in the anode chamber 18, the cathode electrode 13 is placed in the cathode chamber 19, and the electrolyte 17 is injected into the soil chamber 15 until the electrolyte 17 submerges the soil 16 to be repaired. Finally, the anode electrode 12 and the cathode electrode 13 are electrically connected to the DC power supply 11 to repair the soil 16 to be repaired.

[0041] Embodiment 3:

[0042] A particle electrode for soil remediation, comprising: waste toner, biomass carbon powder, graphite fiber, dolomite powder, fly ash, steel slag powder, clay powder, foaming agent, stabilizer and dispersant, wherein the mass percentage content of each component is: 17% of waste toner, 40% of biomass carbon powder, 4% of graphite fiber, 7% of dolomite powder, 7% of fly ash, 10% of steel slag powder, 12% of clay powder, 1% of foaming agent, 1% of stabilizer and 1% of dispersant, the biomass carbon powder is straw charcoal, the foaming agent is sodium bicarbonate, the stabilizer is sodium carboxymethyl cellulose, and the dispersant is sodium dodecyl sulfate.

[0043] An application of a particle electrode for soil remediation, comprising step 1, weighing raw materials; step 2, mixing raw materials; step 3, pressing and forming; step 4, high-temperature calcination; step 5, soil remediation;

[0044] In the above step 1, the sum of the mass percentages of the components is taken as 1, and the raw materials are weighed according to the particle electrode formula ratio;

[0045] In the above step 2, the raw materials weighed in step 1 are placed in a stirring tank, and water is added and mixed to obtain a mixture; wherein the ratio of the raw materials to water is 3-4:1;

[0046] In the above step 3, the mixture obtained in step 2 is pressed into shape using a mold to obtain an electrode blank, which is dried for standby use; wherein a terminal is pre-embedded in the electrode blank;

[0047] In the above step 4, the electrode blank dried in step 3 is placed in a high temperature furnace for calcination, and after calcination, it is cooled to room temperature to obtain a particle electrode; wherein the calcination is performed by staged calcination, specifically: first preheating at 200-600°C for 20-40min, then gradually heating to 700-1000°C, and the calcination time is 2-3h;

[0048] In the above step five, the particle electrode obtained in step four is used as the cathode electrode 13 of the soil electric remediation device 1, and the graphite electrode is used as the anode electrode 12. The soil electric remediation device 1 is used to repair the soil 16 to be repaired. Specifically, the soil 16 to be repaired is placed in the soil chamber 15 of the reaction tank 14, the anode electrode 12 is placed in the anode chamber 18, the cathode electrode 13 is placed in the cathode chamber 19, and the electrolyte 17 is injected into the soil chamber 15 until the electrolyte 17 submerges the soil 16 to be repaired. Finally, the anode electrode 12 and the cathode electrode 13 are electrically connected to the DC power supply 11 to repair the soil 16 to be repaired.

[0049] Experimental example:

[0050] The soil electrokinetic remediation device 1 in the above-mentioned embodiment 1 is used to remediate soil contaminated with perfluorooctanoic acid PFOA. The specific method is as follows: the soil contaminated with PFOA is placed in the soil chamber 15 of the reaction tank 14, and a sufficient amount of water is injected as the electrolyte 17 so that the water level is above the soil in the soil chamber 15, and an aeration pump is placed for oxygenation and aeration. The voltage gradient is controlled at 1V / cm according to the distance between the anode chamber 18 and the cathode chamber 19, and water is replenished every 24 hours to keep the soil in a water-saturated state. The soil is sampled and measured for comparison at 7d and 14d. The weight of the particle electrode used in the soil electrokinetic remediation device 1 is 5% of the soil weight, the aeration rate is 10L / min, the distance between the anode chamber 18 and the cathode chamber 19 is the length of the soil chamber 15, which is 25cm here, so the total voltage is 25V; the results of the measurement and comparison are as follows: the repair effect is best at 14d, and the average removal rate of PFOA in the soil reaches 95.44%, the PFOA removal rate in the soil area closest to the cathode chamber 19 is higher than that in the soil area adjacent to the anode chamber 18, the average pH drops from 7.8-7.9 to 7.1-7.2, and the pH decreases by about 0.8 units. The overall conductivity shows a gradual upward trend, and the weight loss rate of the particle electrode is less than 1%.

[0051] The properties of each embodiment are compared in the following table:

[0052] Example 1 Example 2 Example 3 Waste toner / % 15 13 17 Biomass charcoal / % 45 50 40 Graphite fiber / % 3 4 4 dolomite / % 6 5 7 Fly ash / % 6 7 7 Steel slag powder / % 12 10 10 Clay / % 10 8 12 Foaming agent / % 1 1 1 Stabilizer / % 1 1 1 Dispersant / % 1 1 1

[0053] Based on the above, the advantages of the present invention are: in the formula of the present invention, waste toner is used as a conductive component to achieve waste utilization, and the fine particles of toner can be filled in the gaps of other raw materials, which is helpful to improve the structural stability of the particle electrode. The biomass carbon powder has a rich pore structure and can increase the specific surface area of ​​the particle electrode. The carbon element contained in it can participate in the formation of a conductive network. The graphite fiber can ensure the uniform distribution of the current in the particle electrode, improve the electrochemical properties of the particle electrode, and enhance the mechanical properties of the particle electrode. The dolomite powder can be decomposed to produce magnesium oxide and other substances after calcination, which enhances the stability and strength of the particle electrode. Fly ash can be used as a filling material to reduce the cost of the particle electrode. The steel slag powder contains a variety of metal oxides, which can improve the conductivity and strength of the particle electrode. The clay powder is used as a binder, and the foaming agent is decomposed by heat to produce gas, forming a microporous structure in the particle electrode, increasing its specific surface area. The stabilizer can ensure the stability of the microporous structure, and the dispersant can improve the dispersibility of the raw materials to ensure sufficient mixing. The formula of the present invention has low cost of raw materials, and the prepared particle electrode has good conductivity and corrosion resistance.

[0054] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

Claims

1. A particle electrode for soil remediation, the formula comprising: Waste toner, biomass carbon powder, graphite fiber, dolomite powder, fly ash, steel slag powder, clay powder, foaming agent, stabilizer and dispersant, characterized in that the mass percentage content of each component is: 13-17% of waste toner, 40-50% of biomass carbon powder, 2-4% of graphite fiber, 5-7% of dolomite powder, 5-7% of fly ash, 10-14% of steel slag powder, 8-12% of clay powder, 0.5-1.5% of foaming agent, 0.5-1.5% of stabilizer and 0.5-1.5% of dispersant.

2. The particle electrode for soil remediation according to claim 1, characterized in that: The mass percentage contents of the components are: 15% of waste toner, 45% of biomass carbon powder, 3% of graphite fiber, 6% of dolomite powder, 6% of fly ash, 12% of steel slag powder, 10% of clay powder, 1% of foaming agent, 1% of stabilizer and 1% of dispersant.

3. The particle electrode for soil remediation according to claim 1, characterized in that: The biomass charcoal powder is one or more of straw charcoal, wood charcoal, rice husk charcoal, fruit shell charcoal and bamboo charcoal.

4. The particle electrode for soil remediation according to claim 1, characterized in that: The foaming agent is one or more of sodium bicarbonate, ammonium bicarbonate and azodicarbonamide.

5. The particle electrode for soil remediation according to claim 1, characterized in that: The stabilizer is sodium carboxymethyl cellulose.

6. The particle electrode for soil remediation according to claim 1, characterized in that: The dispersant is one or more of sodium dodecyl sulfate, polyacrylic acid, and sodium lignin sulfonate.

7. An application of a particle electrode for soil remediation, comprising step 1, weighing raw materials; step 2, mixing raw materials; step 3, pressing and forming; step 4, high-temperature calcination; step 5, soil remediation; characterized in that: In the above step 1, the sum of the mass percentages of the components is taken as 1, and the raw materials are weighed according to the particle electrode formula ratio; In the above step 2, the raw materials weighed in step 1 are placed in a stirring tank, water is added and mixed evenly to obtain a mixture; In the above step 3, the mixture obtained in step 2 is pressed into shape using a mold to obtain an electrode blank, which is dried for standby use; wherein a terminal is pre-embedded in the electrode blank; In the above step 4, the electrode blank dried in step 3 is placed in a high temperature furnace for calcination, and after calcination, it is cooled to room temperature to obtain a particle electrode; In the above step 5, the particle electrode obtained in step 4 is used as the cathode electrode (13) of the soil electrokinetic remediation device (1), and the graphite electrode is used as the anode electrode (12), and the soil electrokinetic remediation device (1) is used to remediate the soil to be remediated (16).

8. The use of a particle electrode for soil remediation according to claim 7, characterized in that: In the step 2, the ratio of raw materials to water is 3-4:

1.

9. The use of a particle electrode for soil remediation according to claim 7, characterized in that: In the step 4, the calcination treatment adopts staged calcination, specifically: first preheat at 200-600°C for 20-40min, then gradually increase the temperature to 700-1000°C, and the calcination time is 2-3h.

10. The use of a particle electrode for soil remediation according to claim 7, characterized in that: In the step 5, the soil to be repaired (16) is repaired using the soil electric repair device (1) in the following steps: placing the soil to be repaired (16) in a soil chamber (15) of a reaction pool (14), placing an anode electrode (12) in an anode chamber (18), placing a cathode electrode (13) in a cathode chamber (19), and injecting an electrolyte (17) into the soil chamber (15) until the electrolyte (17) submerges the soil to be repaired (16), and finally electrically connecting the anode electrode (12) and the cathode electrode (13) to a DC power supply (11) to repair the soil to be repaired (16).

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