Uranium-containing wastewater treatment system and method

Abstract

The invention discloses a uranium-containing wastewater treatment system and method, and relates to the field of nuclear industry wastewater treatment. In order to solve the problems in the prior art that the existing electrochemical treatment technology still has some bottlenecks in the aspect of strong acid wastewater treatment, for example, the surface activity of an electrode is reduced due to strong competition of H < + > in a strong acid environment on active sites of the electrode, and the preparation of a functionalized electrode is generally complicated in process and high in cost; the invention provides a uranium-containing wastewater treatment module, which solves the technical problems that the uranium-containing wastewater treatment module seriously affects the industrial application of the technology, the traditional electrochemical method needs higher voltage in the uranium removal process, the problem of high energy consumption is directly caused, and the current requirements on energy conservation and environmental protection are difficult to meet, and the technical scheme provided by the invention is as follows: the uranium-containing wastewater treatment module comprises an anode and a cathode; the anode is made of a metal material, and the cathode is made of a carbon-based material; and the power supply is used for providing constant voltage for the anode and the cathode. The method is suitable for treating uranium-containing wastewater.

Description

Technical Field

[0001] The invention relates to the field of nuclear industry wastewater treatment, and specifically to the treatment of uranium-containing wastewater. Background Art

[0002] In the field of radioactive wastewater treatment, especially the treatment of uranium-containing wastewater, existing technologies face many challenges. Uranium-containing wastewater mainly comes from multiple links such as nuclear fuel mining, refining, nuclear reactor operation and nuclear waste treatment. The uranium contained in these wastewaters is extremely radioactive and chemically toxic. If it is directly discharged without effective treatment, it will enter the ecosystem through soil and water, posing a serious long-term threat to animal, plant and human health. Therefore, finding an efficient and economically feasible treatment method is crucial to the sustainable development of the nuclear industry.

[0003] At present, the most commonly used methods for treating uranium-containing wastewater include adsorption, chemical precipitation, ion exchange and membrane separation technology. The adsorption method usually uses porous materials such as activated carbon and zeolite to remove uranium from water through physical adsorption and chemical adsorption. However, the adsorption capacity of these materials under strong acidic conditions is limited, and the treatment efficiency of large-scale wastewater is insufficient. The chemical precipitation method removes uranium by adding a precipitant to the wastewater to form a precipitate of uranium compounds that are insoluble in water. However, this method will produce a large amount of precipitate, making secondary treatment difficult, increasing costs and environmental burdens.

[0004] Ion exchange technology uses specific ion exchange resins to exchange with uranium ions in wastewater to achieve the purpose of removing uranium. Although this technology works well in treating low-concentration wastewater, it has poor adaptability to highly acidic wastewater, and the resin regeneration process is complex and costly. Membrane separation technologies such as reverse osmosis and ultrafiltration use the selective permeability of membranes to remove uranium from wastewater. Although the removal effect is good, the chemical stability and anti-pollution performance of the membrane become bottlenecks when treating strongly acidic and high-concentration wastewater. At the same time, the replacement and maintenance costs of the membrane also make it face certain challenges in industrial applications.

[0005] In recent years, electrochemical treatment technology has gradually attracted attention due to its high efficiency and controllable characteristics. Electrochemical treatment can remove pollutants from water through electric fields, including processes such as electroreduction, electrosorption and electrocoagulation. The advantage of electrochemical treatment is that it does not require the addition of additional chemical agents, has high removal efficiency and low environmental pollution risk. However, the existing electrochemical treatment technology still has some bottlenecks in the treatment of strongly acidic wastewater. For example, the strong competition of H+ in a strongly acidic environment for electrode active sites leads to reduced electrode surface activity. In addition, the preparation of functionalized electrodes is usually complex and costly, which seriously affects the industrial application of the technology. At the same time, traditional electrochemical methods require higher voltages in the process of removing uranium, which directly leads to high energy consumption problems and is difficult to meet the current requirements for energy conservation and environmental protection. Summary of the invention

[0006] To solve the existing problems in the prior art, the existing electrochemical treatment technology still has some bottlenecks in the treatment of strongly acidic wastewater, such as the strong competition of H+ in a strongly acidic environment for the active sites of the electrode, resulting in reduced electrode surface activity, and the preparation of functionalized electrodes is usually complex and costly, which seriously affects the industrial application of the technology. The traditional electrochemical method requires a higher voltage in the process of removing uranium, which directly leads to the problem of high energy consumption and is difficult to meet the current technical problems of energy conservation and environmental protection. The technical solution provided by the present invention is:

[0007] A treatment module for uranium-containing wastewater, comprising:

[0008] Anode and cathode;

[0009] The anode is made of metal material, and the cathode is made of carbon-based material;

[0010] A power supply of a constant voltage is provided to the anode and cathode.

[0011] Furthermore, a preferred embodiment is provided, wherein the anode is made of one or more of zinc, iron, aluminum, copper, galvanized iron, iron-zinc alloy, nickel and nickel foam.

[0012] Furthermore, a preferred embodiment is provided, wherein the cathode is realized by one or more of activated carbon fiber, activated carbon, graphite felt, carbon felt and carbon cloth.

[0013] Furthermore, a preferred embodiment is provided, wherein the voltage is a direct current power supply.

[0014] Furthermore, a preferred embodiment is provided, wherein the voltage of the DC power supply is at least 0.1V.

[0015] Based on the same inventive concept, the present invention also provides a treatment system for uranium-containing wastewater, comprising a reaction pool for accommodating an aqueous solution containing hexavalent uranium, and the module, wherein an anode and a cathode in the module are used to be inserted into the aqueous solution.

[0016] Based on the same inventive concept, the present invention also provides a method for treating uranium-containing wastewater, which is implemented based on the system and includes:

[0017] Collect the steps to start processing instructions;

[0018] The step of generating a driving signal;

[0019] Steps to generate a stirring signal.

[0020] Based on the same inventive concept, the present invention also provides a computer storage medium for storing a computer program. When the computer program is read by a computer, the computer executes the method described.

[0021] Based on the same inventive concept, the present invention also provides a computer, including a processor and a storage medium. When the processor reads a computer program stored in the storage medium, the computer executes the method described.

[0022] Based on the same inventive concept, the present invention also provides a computer program product, which is a computer program. When the computer program is read by a computer, the method described above is implemented.

[0023] Compared with the prior art, the technical solution provided by the present invention is beneficial in that:

[0024] The present invention provides a treatment system for uranium-containing wastewater. In the uranium-containing wastewater treatment system, by selecting a specific anode material and utilizing its electrochemical corrosion characteristics, metal ions are effectively released. These metal ions react with uranium in the solution to form precipitation or be reduced, which significantly improves the removal efficiency of uranium. Compared with existing electrochemical treatment technologies, this method can utilize the characteristics of different metals and provide flexible solutions for wastewater with different pH values, breaking through the bottleneck of complex and costly electrode functionalization in conventional electrochemical technologies.

[0025] The present invention provides a treatment system for uranium-containing wastewater, which uses carbon-based materials as cathodes, and utilizes their large specific surface area and good electrical conductivity to further remove uranium from the solution through electroreduction and electroadsorption processes, thereby greatly improving the treatment efficiency. Compared with the single electrochemical reduction method commonly used in the prior art, the carbon-based cathode material combines multiple electrochemical mechanisms to more efficiently fix the uranium element, avoiding the situation in which the electrode activity of the traditional method is reduced in a strong acid environment.

[0026] The present invention provides a treatment system for uranium-containing wastewater, in which a voltage-stabilized DC power supply provides a constant voltage to drive the electrochemical reaction, and can achieve a uranium removal efficiency of up to 99% under low voltage (0.1V) conditions. This design effectively reduces power consumption, and in particular, compared with other treatment systems that require high voltage or even multi-stage power supply, this solution greatly reduces energy costs, reflecting the energy saving and high efficiency of the system.

[0027] The present invention provides a treatment system for uranium-containing wastewater, which increases the conductivity of the solution by adding electrolytes such as sodium chloride or sodium nitrate into the reaction pool, thereby significantly improving the efficiency of the electrochemical reaction. This method improves the current distribution between electrodes, especially in the treatment process of high-concentration uranium wastewater, accelerates the migration and deposition process of uranium, and solves the problem of uneven treatment caused by insufficient conductivity in traditional methods.

[0028] The present invention provides a treatment system for uranium-containing wastewater, which uses a stirring device to fully mix the solution in the reaction pool, ensuring that the metal ions generated by the anode are fully in contact with the cathode, and further improving the uranium removal efficiency. Compared with the existing static reaction method, the introduction of the stirring device reduces the influence of the concentration gradient of the reactants, ensures the uniformity of the reaction, and enables a high removal rate to be achieved in a relatively short time.

[0029] The present invention provides a treatment system for uranium-containing wastewater. The whole system operates at room temperature and in a normal air environment, without the need for complex temperature control, thus reducing operating costs and operating difficulties. Compared with the existing electrochemical treatment method that requires strict temperature control, the simplified operating conditions of this solution make it more suitable for industrial-scale production, significantly improving the practicality and ease of operation of the system.

[0030] The invention provides a system for treating uranium-containing wastewater, which is suitable for treating uranium-containing wastewater. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is a comparison diagram of the original activated carbon fiber felt cathode and the electrode after 24 hours of reaction;

[0032] Among them, the left side is the original activated carbon fiber felt, and the right side is the activated carbon fiber felt after 24 hours of reaction.

[0033] Figure 2 This is a scanning electron microscope image of the activated carbon fiber felt cathode after the reaction was carried out for 24 hours;

[0034] Figure 3 This is the EDS energy spectrum of the activated carbon fiber felt cathode after the reaction was carried out for 24 hours. DETAILED DESCRIPTION

[0035] In order to make the advantages and benefits of the technical solution provided by the present invention more clearly reflected, the technical solution provided by the present invention is now further described in detail with reference to the accompanying drawings, specifically:

[0036] Embodiment 1: This embodiment provides a treatment module for uranium-containing wastewater, including:

[0037] Anode and cathode;

[0038] The anode is made of metal material, and the cathode is made of carbon-based material;

[0039] A power supply of a constant voltage is provided to the anode and cathode.

[0040] Specifically, the technical solution provided in this embodiment includes:

[0041] Reaction tank:

[0042] To hold anode and cathode materials:

[0043] The anode material is a metal material with good conductivity, including but not limited to zinc, iron, aluminum, copper, galvanized iron, iron-zinc alloy, nickel, and nickel foam. These materials have different electrochemical properties and can release metal ions through corrosion, thereby promoting uranium removal.

[0044] The cathode material is a carbon-based material, including activated carbon fiber, activated carbon, graphite felt, carbon felt, carbon cloth, etc. These materials provide good conductivity and large specific surface area for electroreduction and adsorption processes.

[0045] Regulated DC power supply:

[0046] A constant voltage is provided to maintain the stability of the electrochemical reaction, and the minimum voltage requirement is 0.1V to ensure efficient uranium removal under low energy consumption conditions.

[0047] Specific reaction between the metal ions of the anode corrosion and the cathode:

[0048] The metal ions produced at the anode undergo specific electrosorption, electroreduction and electrocoagulation reactions at the cathode, and multiple technologies are combined to form an effective uranium removal effect.

[0049] Supporting Electrolyte:

[0050] Additional supporting electrolytes such as sodium chloride and sodium nitrate are added to the solution to enhance the conductivity of the solution and further improve the uranium removal efficiency. The concentration of the supporting electrolyte is generally 0.01 to 0.5 mol / L.

[0051] Operating conditions:

[0052] Suitable for strong acidic or alkaline environments, pH range is 0 to 14.

[0053] The reaction is carried out at room temperature and does not require special temperature control, which simplifies operating requirements and reduces costs.

[0054] Stirring device:

[0055] Physical stirring is used to mix the solution thoroughly to improve the uranium removal efficiency. The stirring device is optional, but its presence can significantly improve the treatment effect of the system.

[0056] Embodiment 2: This embodiment further limits the treatment module for uranium-containing wastewater provided in embodiment 1, wherein the anode is realized by one or more of zinc, iron, aluminum, copper, galvanized iron, iron-zinc alloy, nickel and nickel foam.

[0057] Embodiment 3: This embodiment further limits the treatment module for uranium-containing wastewater provided in embodiment 1, and the cathode is realized by one or more of activated carbon fiber, activated carbon, graphite felt, carbon felt and carbon cloth.

[0058] Embodiment 4: This embodiment further limits the uranium-containing wastewater treatment module provided in Embodiment 1, and the voltage is a direct current power supply.

[0059] Embodiment 5: This embodiment further limits the uranium-containing wastewater treatment module provided in embodiment 4, and the voltage of the DC power supply is at least 0.1V.

[0060] Embodiment 6: This embodiment provides a system for treating uranium-containing wastewater, including a reaction pool for accommodating an aqueous solution containing hexavalent uranium, and the module provided in embodiment 1, in which an anode and a cathode are used to be inserted into the aqueous solution.

[0061] Embodiment 7: This embodiment provides a method for treating uranium-containing wastewater, which is implemented based on the system provided in Embodiment 6 and includes:

[0062] Collect the steps to start processing instructions;

[0063] The step of generating a driving signal;

[0064] Steps to generate a stirring signal.

[0065] Embodiment 8: This embodiment provides a computer storage medium for storing a computer program. When the computer program is read by a computer, the computer executes the method provided in embodiment 7.

[0066] Embodiment 9: This embodiment provides a computer, including a processor and a storage medium. When the processor reads a computer program stored in the storage medium, the computer executes the method provided in embodiment 7.

[0067] Embodiment 10: This embodiment provides a computer program product, which is a computer program. When the computer program is read by a computer, the method provided in embodiment 7 is implemented.

[0068] Implementation Method XI: Combination Figure 1-3 This embodiment is described in detail by using specific examples to further describe the technical solution provided above. Specifically:

[0069] The purpose of this embodiment is to provide a system and method for treating uranium-containing wastewater, which is achieved through the following technical scheme: in an aqueous solution containing hexavalent uranium, a metal material with good conductivity is used as an anode and a carbon-based material is used as a cathode to form an electrochemical treatment system, a regulated DC power supply is used to provide a constant voltage, and the metal ions generated by the corrosion of the metal anode and the specific reaction of the cathode in the solution are utilized to achieve the coupling of electrosorption, electroreduction, electrocoagulation and other technologies, thereby promoting the removal of uranium in the solution.

[0070] This embodiment provides a treatment system for uranium-containing wastewater, including a reaction cell, a cathode and an anode. The reaction cell contains an aqueous solution of hexavalent uranium, the anode is a metal material, the cathode is a carbon material, and a regulated DC power supply is connected between the cathode and the anode through a wire.

[0071] The anode material includes, but is not limited to, one or more of zinc, iron, aluminum, copper, galvanized iron, iron-zinc alloy, nickel, and nickel foam.

[0072] The cathode material includes, but is not limited to, one or more of activated carbon fiber, activated carbon, graphite felt, carbon felt, and carbon cloth.

[0073] The minimum applied voltage of the regulated DC power supply is 0.1V.

[0074] The method is also applicable to the treatment of alkaline uranium-containing wastewater, and the applicable pH range is 0 to 14.

[0075] The method does not need to control the temperature during operation and is carried out at room temperature and in an air atmosphere.

[0076] When additional supporting electrolytes are added to the uranium-containing waste liquid, the uranium removal efficiency will be enhanced; the supporting electrolytes include but are not limited to one or more of sodium chloride, sodium nitrate, sodium sulfate, potassium chloride, potassium nitrate, and potassium sulfate.

[0077] The concentration of the additional supporting electrolyte is 0.01-0.5 mol / L.

[0078] The uranium removal efficiency is enhanced when additional stirring is added to the system.

[0079] Compared with the prior art, this embodiment has the following beneficial effects:

[0080] The electrode material used in this embodiment is a commercial product with low price and wide source. It solves the problem that the functional electrode materials that are highly relied on in the current electrochemical treatment of uranium-containing wastewater are complicated to prepare, costly and difficult to mass produce, and is more suitable for industrial applications.

[0081] The method provided in this embodiment utilizes the characteristics of different metal anodes and metal ions generated by their corrosion in different environments to couple two or more technologies of electroadsorption, electroreduction, electrocoagulation, and electrocatalysis, thereby further enhancing the treatment effect of uranium-containing wastewater.

[0082] The method provided in this embodiment is applicable to uranium-containing wastewater in a wide range of pH environments, and in particular, the treatment effect of uranium-containing wastewater with strong acidity (pH≤3) is better than most electrochemical technologies currently reported.

[0083] Calculation method of uranium removal efficiency (RE):

[0084]

[0085] C0(mg / L) and C e (mg / L) represent the uranium concentration in the solution before and after electrochemical treatment, respectively.

[0086] Embodiment 1:

[0087] 30 mL of uranium (VⅠ) aqueous solution was added into the reaction vessel, wherein the uranium concentration was 50 mg / L and the pH was 2.0. High-purity zinc metal was used as the anode and activated carbon fiber felt was used as the cathode. The uranium removal experiment was carried out at a DC voltage of 0.1 V. After reacting for 24 hours at room temperature in an air atmosphere, the uranium removal efficiency can reach 89.5% through the measurement and calculation of the residual uranium concentration.

[0088] Example 2: Please refer to Figure 1-3 ;

[0089] 30 mL of uranium (VⅠ) aqueous solution was added into the reaction vessel, wherein the uranium concentration was 500 mg / L and the pH was 2.0. The uranium removal experiment was carried out at a DC voltage of 0.1 V using galvanized iron as the anode and activated carbon fiber felt as the cathode. After reacting for 8 hours at room temperature in an air atmosphere, the uranium removal efficiency can reach 52.4% through the measurement and calculation of the residual uranium concentration.

[0090] Embodiment 3:

[0091] When other conditions in Example 1 remain unchanged, the anode material is changed to high-purity metallic iron. After reacting for 24 hours at room temperature in an air atmosphere, it can be seen from the measurement and calculation of the remaining uranium concentration that the uranium removal efficiency can reach 89.41%.

[0092] Embodiment 4:

[0093] In Example 1, with other conditions unchanged, the anode material was changed to galvanized iron, and supporting electrolyte NaCl was added to the solution to a concentration of 0.2 mol / L. After reacting in an air atmosphere for 3 hours, the uranium removal efficiency could reach 99.36% through measurement and calculation of the remaining uranium concentration.

[0094] Embodiment 5:

[0095] When other conditions in Example 1 remain unchanged, the pH of the uranium-containing aqueous solution is changed to 1.0, the DC voltage is changed to 2V, and after reacting for 9 hours at room temperature in an air atmosphere, the uranium removal efficiency can reach 99.96% through measurement and calculation of the remaining uranium concentration.

[0096] Embodiment 6:

[0097] In Example 5, when other conditions remain unchanged, the volume of the uranium-containing aqueous solution is changed to 40 mL, the DC voltage is changed to 1 V, and a magnetic stirrer is used to stir at a stirring rate of 750 rpm. After reacting for 1 hour at room temperature in an air atmosphere, it can be seen from the measurement and calculation of the residual uranium concentration that the uranium removal efficiency can reach 99.5%.

[0098] Embodiment 7:

[0099] With other conditions in Example 1 unchanged, the anode material was changed to high-purity copper, the DC voltage was changed to 3V, and after reacting for 4 hours at room temperature and in an air atmosphere, it was found through measurement and calculation of the residual uranium concentration that the uranium removal efficiency could reach 69.71%.

[0100] Embodiment 8:

[0101] When other conditions in Example 7 remain unchanged, the solution pH is adjusted to 10.0, and the uranium removal efficiency can reach 99.9% through the measurement and calculation of the residual uranium concentration.

[0102] The technical solution provided by the present invention is further described in detail above through several specific implementation modes in order to highlight the advantages and benefits of the technical solution provided by the present invention. However, the several specific implementation modes described above are not intended to be used as limitations on the present invention. Any reasonable modification and improvement of the present invention, combination of implementation modes and equivalent substitution within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A treatment module for uranium-containing wastewater, characterized in that: include: Anode and cathode; The anode is made of metal material, and the cathode is made of carbon-based material; A power supply of a constant voltage is provided to the anode and cathode.

2. A uranium-containing wastewater treatment module according to claim 1, characterized in that: The anode is made of one or more of zinc, iron, aluminum, copper, galvanized iron, iron-zinc alloy, nickel and foamed nickel.

3. A uranium-containing wastewater treatment module according to claim 1, characterized in that: The cathode is realized by one or more of activated carbon fiber, activated carbon, graphite felt, carbon felt and carbon cloth.

4. A treatment module for uranium-containing wastewater according to claim 1, characterized in that: The voltage is a direct current power supply.

5. A uranium-containing wastewater treatment module according to claim 4, characterized in that: The voltage of the DC power supply is at least 0.1V.

6. A system for treating uranium-containing wastewater, characterized in that: The invention comprises a reaction cell for containing an aqueous solution containing hexavalent uranium, and the module according to claim 1, wherein an anode and a cathode in the module are used to be inserted into the aqueous solution.

7. A method for treating uranium-containing wastewater, characterized in that: The method is implemented based on the system of claim 6, comprising: Collect the steps to start processing instructions; The step of generating a driving signal; Steps to generate a stirring signal.

8. A computer storage medium for storing a computer program, characterized in that: When the computer program is read by a computer, the computer executes the method of claim 7.

9. A computer, comprising a processor and a storage medium, characterized in that: When the processor reads the computer program stored in the storage medium, the computer executes the method of claim 7 .

10. A computer program product, being a computer program, characterized in that When the computer program is read by a computer, the method according to claim 7 is implemented.

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