System and method for efficiently treating inter-cooling water by using electrochemical method
By using a three-stage series design of gradient filtration unit and electrolytic cell, combined with modified biochar electrode, the corrosion control problem of the inter-power plant cooling water system was solved, achieving efficient and low-cost pollutant removal and solid waste resource utilization.
Patent Information
- Application Number
- CN202511061153.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-30
- Publication Date
- 2025-11-07
AI Technical Summary
In existing technologies, corrosion control in power plant cooling water systems is difficult to solve effectively. Traditional mixed-bed ion exchange processes have high operation and maintenance costs and complex regeneration processes, and lack the ability to respond quickly to sudden water quality deterioration.
The system employs a three-stage series design consisting of a gradient filtration unit, a low-pressure electrolytic cell, and a high-pressure electrolytic cell. Combined with a coal gangue-modified straw biochar anode and a microencapsulated calcium alginate-distillers' grains biochar cathode, the system achieves efficient graded removal of pollutants and optimized energy consumption through gradient voltage and a baffle-like flow channel design.
It significantly reduces operation and maintenance costs, improves treatment efficiency, achieves efficient removal of pollutants, and enables resource utilization of solid waste through the material properties of biochar electrodes, providing a stable corrosion control solution.
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Figure CN120903643A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application belongs to the technical field of intercooling water treatment, and relates to a system and method for efficiently treating intercooling water by using an electrochemical method. BACKGROUND
[0002] Corrosion prevention and control of the intercooling water system of a power plant is a key challenge to ensure its safe and economic operation. The corrosion process of the system is driven by multiple factors: SO4 2- , Fe 3+ and iron oxide suspended particles produced by the electrochemical corrosion of carbon steel pipelines and heat exchangers. These factors interact with each other to form a complex corrosion mechanism: excessive SO4 2- and Cl - synergistically damage the metal passivation film, causing stainless steel pitting corrosion and carbon steel uniform corrosion; Fe 3+ acts as a strong oxidizing agent to accelerate the corrosion of copper alloy components; and iron oxide suspensions deposit on the surface of pipelines and equipment to form a porous scale layer, which not only hinders heat conduction but also induces serious under-deposit corrosion. The coupling effect of this multiple corrosion mechanism continuously weakens the system life and may even cause unplanned shutdown accidents.
[0003] For a long time, the traditional mixed bed ion exchange process for controlling corrosion has inherent defects and cannot meet the demand. The core problem of this process is the high operation and maintenance cost and the complex regeneration process: in the face of complex corrosion media such as SO4 2- and Fe 3+ , the resin needs to be regenerated frequently using acid and alkali agents to restore activity. A single regeneration not only consumes 30% to 50% of the industrial water capacity of the system, but also produces a large amount of high-salinity wastewater. Frequent shutdown for regeneration causes the annual agent cost to rise to the level of hundreds of thousands of yuan, and the regeneration cycle cannot match the dynamically changing water quality, accelerating the irreversible decay of resin performance and highlighting the passivity of this technology.
[0004] The complexity of the regeneration of the mixed bed process also brings about systematic risks. Simultaneous regeneration of anion and cation resins requires accurate control of the acid-alkali ratio to maintain balance, and in actual operation, parameter deviation can easily cause cross-contamination of the resins, causing a sharp drop in ion exchange capacity. This technology route is essentially a passive repair and lacks the ability to respond quickly to sudden deterioration of water quality, and the lag in regeneration operation often causes the concentration of corrosion media to get out of control. SUMMARY
[0005] To solve the problems in the prior art, the present application provides a system and method for efficiently treating intercooling water by using an electrochemical method, which not only significantly improves the treatment efficiency, but also greatly reduces the operation and maintenance cost, and realizes the high-value utilization of agricultural and industrial solid waste.
[0006] To achieve the above object, the present application adopts the following technical solutions to achieve the above object: In a first aspect, the present application provides a system for efficiently treating intercooling water by electrochemical method, comprising a gradient filtration unit, a low-voltage electrolytic cell and a high-voltage electrolytic cell; the bottom outlet of the gradient filtration unit is connected to the bottom inlet of the low-voltage electrolytic cell; the top outlet of the low-voltage electrolytic cell is connected to the top inlet of the high-voltage electrolytic cell; The gradient filtration unit comprises a manganese sand layer and a quartz sand layer from top to bottom. The anode of the low-voltage electrolytic cell and the high-voltage electrolytic cell is filled with coal gangue modified straw biochar material, and the cathode is filled with microencapsulated calcium alginate-distiller's grain biochar composite material; the working voltage of the low-voltage electrolytic cell is lower than that of the high-voltage electrolytic cell.
[0007] Preferably, the volume ratio of the manganese sand layer to the quartz sand layer is 1: (1.5-2.0).
[0008] Preferably, the particle size of the manganese sand layer is 1-2 mm, and the particle size of the quartz sand layer is 0.5 mm.
[0009] Preferably, the working voltage of the low-voltage electrolytic cell is 3-5 V, and the working voltage of the high-voltage electrolytic cell is 6-8 V.
[0010] Preferably, the preparation method of the coal gangue modified straw biochar material is as follows: The straw is crushed and pyrolyzed under anaerobic conditions to obtain straw biochar; The coal gangue is crushed and ball milled to obtain coal gangue powder; The coal gangue powder and the straw biochar are mixed and pyrolyzed under anaerobic conditions, and then the mixture is cooled, washed with acid, washed, and dried to obtain the coal gangue modified straw biochar material.
[0011] Preferably, the mass ratio of the coal gangue powder to the straw biochar is 2:5.
[0012] Preferably, the preparation method of the microencapsulated calcium alginate-distiller's grain biochar composite material is as follows: The distiller's grain is dried and crushed, and then pyrolyzed under anaerobic conditions to obtain distiller's grain biochar; The sodium alginate suspension and the distiller's grain biochar are mixed to obtain a mixed solution; the mixed solution is dropped into a CaCl2 solution for solidification reaction, and then washed, frozen, and dried to obtain the microencapsulated calcium alginate-distiller's grain biochar composite material.
[0013] Preferably, the mass concentration of the sodium alginate suspension is 0.5%-1.5%, and the mass ratio of the sodium alginate suspension to the distiller's grain biochar is (3-5):1.
[0014] In a second aspect, the present application provides a method for efficiently treating intercooling water by electrochemical method, comprising the following steps: The intercooling water to be treated is introduced into a gradient filtration unit, and sequentially filtered through manganese sand layer and quartz sand layer to remove iron suspended matter; The filtered water is introduced into a low-voltage electrolytic cell for primary electrolysis treatment to remove part of SO4 2- and Fe 3+ pollutants in the water; The water treated by the low-voltage electrolytic cell is introduced into a high-voltage electrolytic cell for deep electrolysis treatment to remove the remaining SO4 2- , Fe 3+ pollutants and residual pollutants.
[0015] Preferably, the method further comprises: When the anode adsorption capacity decreases to 70-75% of the initial value, backwashing regeneration is adopted, and the backwashing parameters are: water flow rate 5-8 m / h, and duration 15-30 minutes; When the cathode adsorption capacity decreases to 70-75% of the initial value, citric acid solution soaking regeneration is adopted, and the soaking parameters are: citric acid solution concentration 0.5-1.0 mol / L, temperature 40-50 DEG C, and time 2-4 hours.
[0016] Compared with the prior art, the present application has the following beneficial effects: The present application realizes efficient purification of intercooling water by three-stage series treatment device: iron suspended matter is physically intercepted by the gradient filtration unit, main pollutants are primarily removed by the low-voltage electrolytic cell, and residual pollutants are deeply treated by the high-voltage electrolytic cell. Meanwhile, the electrode combination of coal gangue modified straw biochar anode and microencapsulated calcium alginate-distiller's grains biochar cathode is adopted to realize selective adsorption of SO4 2- and Fe 3+ ; energy consumption is optimized by setting gradient working voltage, main body pollutants are removed by the low-voltage electrolytic cell, and the final effluent quality is ensured by the high-voltage electrolytic cell. In addition, the water flow direction is alternately changed by the design of the baffling type flow channel, thereby enhancing the mass transfer efficiency. BRIEF DESCRIPTION OF DRAWINGS
[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments. It should be understood that the following drawings only show some of the embodiments of the present application, and therefore should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can also be obtained without creative labor on the basis of these drawings.
[0018] Figure 1A schematic diagram of a system for efficiently treating intercooling water by using an electrochemical method according to the present application; Figure 2 A schematic diagram of treatment effects of the device on SO4 2- at different potentials in Example 1 of the present application; Figure 3 A schematic diagram of treatment effects of the device on Fe 3+ at different potentials in Example 1 of the present application.
[0019] 1, gradient filtration unit; 11, manganese sand layer; 12, quartz sand layer; 2, low-voltage electrolytic cell; 3, high-voltage electrolytic cell. DETAILED DESCRIPTION
[0020] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme of the embodiments of the present application will be described clearly and completely below in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are some embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings can be arranged and designed in various different configurations.
[0021] Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed present application, but only represents selected embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative labor are within the scope of protection of the present application.
[0022] It should be noted that: similar reference numerals and letters represent similar items in the following drawings, therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.
[0023] In the description of the embodiments of the present application, it should be noted that, if the orientation or position relationship indicated by the terms "upper", "lower", "horizontal", "inner" and the like is based on the orientation or position relationship shown in the drawings, or is the orientation or position relationship when the product of the present application is usually placed, which is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the indicated device or element must have a particular orientation, be constructed and operated in a particular orientation, therefore, it cannot be understood as a limitation on the present application. In addition, the terms "first", "second" and the like are only used for differentiation in description, and cannot be understood as indicating or implying relative importance.
[0024] In addition, if the term "horizontal" appears, it does not mean that the component must be absolutely horizontal, but can be slightly inclined. For example, "horizontal" only means that its direction is relatively more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly inclined.
[0025] In the description of the embodiments of the present application, it should also be noted that unless otherwise explicitly specified and limited, if the terms "arrange", "mount", "connect", "connect" appear, they should be understood in a broad sense, for example, they can be fixedly connected, or can be detachably connected, or integrally connected, can be mechanically connected, or can be electrically connected, can be directly connected, or indirectly connected through an intermediate medium, or the internal communication of two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.
[0026] The present application will be described in further detail below with reference to the accompanying drawings: The first object of the present application is to provide a system for efficiently treating intercooling water by electrochemical method, as shown in Figure 1 The gradient filtration unit 1, the low-voltage electrolytic cell 2 and the high-voltage electrolytic cell 3 are connected; the low-voltage electrolytic cell 2 top outlet and the high-voltage electrolytic cell 3 top inlet are connected; The gradient filtration unit 1 comprises a manganese sand layer 11 and a quartz sand layer 12 from top to bottom. The anode of the low-voltage electrolytic cell 2 and the high-voltage electrolytic cell 3 is filled with coal gangue modified straw biochar material, and the cathode is filled with microencapsulated calcium alginate-distiller's grain biochar composite material; the working voltage of the low-voltage electrolytic cell 2 is lower than that of the high-voltage electrolytic cell 3.
[0027] The electrochemical method intercooling water treatment system provided by the present application realizes efficient graded removal of pollutants through the three-stage series design of the gradient filtration unit 1, the low-voltage electrolytic cell 2 and the high-voltage electrolytic cell 3. The gradient filtration unit 1 adopts a double-layer filter bed structure of manganese sand layer 11 and quartz sand layer 12, effectively traps large-particle impurities such as iron suspended solids, and provides pretreatment guarantee for subsequent electrochemical treatment; the low-voltage electrolytic cell 2 drives the selective adsorption of coal gangue modified straw biochar anode and microencapsulated calcium alginate-distiller's grain biochar cathode at a lower voltage, efficiently removes most of SO4 2- and Fe 3+ pollutants in water; the high-voltage electrolytic cell 3 purifies the residual ions at a higher voltage, and realizes energy consumption optimization through voltage gradient control. Secondly, the system realizes the alternating change of water flow direction (intercooling water enters from the top of the gradient filtration unit 1 and exits from the bottom; the low-voltage electrolytic cell 2 enters from the bottom and exits from the top; the high-voltage electrolytic cell 3 enters from the top and exits from the bottom) through the design of the baffling type flow channel, thereby strengthening the mass transfer efficiency. At the same time, the material properties of the biochar electrode are used to realize targeted adsorption of pollutants, so that SO4 2- is adsorbed on the anode, and Fe 3+ is adsorbed on the cathode, realizing effective removal of iron suspended solids and ions, and having the advantages of resource utilization of solid waste and green treatment.
[0028] The volume ratio of the manganese sand layer 11 and the quartz sand layer 12 is 1: (1.5-2.0), and the particle size of the manganese sand layer 11 is 1-2 mm, and the particle size of the quartz sand layer 12 is 0.5 mm. Through the synergistic effect of coarse filtration of the upper layer of manganese sand with large particle size and fine filtration of the lower layer of fine quartz sand, both high iron suspended substance interception efficiency and prevention of premature clogging of the filter layer are ensured.
[0029] Illustratively, the working voltage of the low-voltage electrolytic cell 2 is 3-5 V, and the working voltage of the high-voltage electrolytic cell 3 is 6-8 V. By forming a gradient voltage system with the low-voltage electrolytic cell 2 and the high-voltage electrolytic cell 3, both efficient removal of pollutants in stages and optimization of energy consumption are achieved. The low-voltage electrolytic cell 2 preferentially removes most of SO4 2- and Fe 3+ plasma at a lower energy consumption, and the high-voltage electrolytic cell 3 performs deep purification on residual pollutants. This gradient voltage design avoids both energy waste caused by a single high voltage and the problem of incomplete treatment at a low voltage.
[0030] The preparation method of the coal gangue modified straw biochar material is as follows: The straw is crushed to 80-100 meshes, and then pyrolysis is carried out at 600-800 DEG C under anaerobic conditions for 2-4 hours to obtain straw biochar; The coal gangue is crushed and ball milled to obtain coal gangue powder; The coal gangue powder and the straw biochar are mixed in a mass ratio of 2:5, and then pyrolysis is carried out at 600-800 DEG C under anaerobic conditions for 2-4 hours. After cooling, acid washing (such as soaking in 1 mol / L dilute hydrochloric acid for 24-48 hours), washing and drying are carried out to obtain the coal gangue modified straw biochar material.
[0031] The present application adopts the synergistic pyrolysis treatment of straw and coal gangue, so that the coal gangue modified straw biochar material has both the porous properties of biochar and the mineral activity of coal gangue. The conductivity and specific surface area of the electrode are improved, and the specific adsorption capacity of SO4 2- is also enhanced. The stage-by-stage anaerobic pyrolysis process ensures the stability of the carbon skeleton structure, and the subsequent acid washing treatment not only effectively activates the surface of the material, but also significantly improves the conductivity and ion exchange capacity of the electrode.
[0032] The preparation method of the microencapsulated calcium alginate-distiller's grains biochar composite material is as follows: The distiller's grains are dried at 60-80 DEG C, crushed to 1-5 mm, and then pyrolysis is carried out at 300-600 DEG C under anaerobic conditions for 2-4 hours to obtain distiller's grains biochar; The mixed solution is obtained by mixing a sodium alginate suspension with a mass concentration of 0.5% to 1.5% and vinasse biochar at a mass ratio (3 to 5):1; the mixed solution is dropped into a calcium chloride (CaCl2) solution at a rate of 10 mL / min for solidification for 10 to 20 h, and the microencapsulated calcium alginate-vinasse biochar composite material is obtained after washing with desalted water, freezing and drying.
[0033] The present application adopts vinasse biochar as a core substrate, and forms a stable three-dimensional network structure through uniform coating of a sodium alginate solution and cross-linking solidification of calcium ions. 3+ The present application not only retains the high adsorption property of vinasse biochar, but also enhances the selective capture capacity of the material for Fe
[0034] The second object of the present application is to provide a method for efficiently treating intercooling water by using an electrochemical method, comprising the following steps: The intercooling water to be treated is introduced into a gradient filtration unit 1, and sequentially filtered through a manganese sand layer 11 and a quartz sand layer 12 to remove iron suspended matter; The filtered water is introduced into a low-voltage electrolytic cell 2 for primary electrolytic treatment to remove part of SO4 2- and Fe 3+ pollutants in the water; The water treated by the low-voltage electrolytic cell 2 is introduced into a high-voltage electrolytic cell 3 for deep electrolytic treatment to remove residual SO4 2- , Fe 3+ pollutants and residual pollutants.
[0035] The electrochemical method for treating intercooling water provided by the present application realizes efficient graded removal of pollutants through a three-stage synergistic process. Specifically, the gradient filtration unit 1 first removes large-particle impurities such as iron suspended matter through physical interception; the low-voltage electrolytic cell 2 selectively removes main ionic pollutants under a mild electric field, significantly reducing the load of subsequent treatment; and the high-voltage electrolytic cell 3 performs deep purification on residual pollutants to ensure that the effluent water quality meets the standard. The method forms a complete treatment chain from physical filtration to electrochemical adsorption, not only improves the overall treatment efficiency, but also realizes reasonable allocation of energy consumption, and provides a stable and reliable treatment scheme for the intercooling water system.
[0036] For example, when the anode adsorption capacity decreases to 70% to 75% of the initial value, backwashing regeneration is adopted; the backwashing parameters are: water flow rate 5 to 8 m / h, and duration 15 to 30 minutes; according to the characteristics of the coal gangue modified straw biochar anode, the backwashing method can effectively remove the intercepted pollutants and avoid mechanical damage to the porous structure.
[0037] When the cathode adsorption capacity decreases to 70%~75% of the initial value, citric acid solution is used for soaking regeneration; the soaking parameters are: citric acid solution concentration 0.5~1.0 mol / L, temperature 40~50℃, time 2~4 hours; for the calcium alginate-distiller's grains biochar cathode, the chelating property of citric acid solution is used to selectively desorb iron ions under mild conditions.
[0038] Example 1 Straw is crushed to 100 mesh, pyrolyzed under 600℃ and anaerobic condition for 4 hours to obtain straw biochar. Coal gangue is crushed, ball milled for 3 hours to powder, then mixed with straw biochar at a mass ratio of 2:5, pyrolyzed under 600℃ and anaerobic condition for 4 hours. After cooling, soaked in 1 mol / L dilute hydrochloric acid solution for 24 hours, washed to neutral and dried to obtain coal gangue modified straw biochar material.
[0039] Distiller's grains are dried at 80°C, ground into 3mm fragments, pyrolyzed under 600℃ and anaerobic condition for 4 hours to obtain distiller's grains biochar. A sodium alginate suspension with a mass concentration of 1.0% is mixed with distiller's grains biochar at a mass ratio of 4:1, and dropped into a 0.1 mol / L calcium chloride solution at a rate of 10 mL / min, and solidified for 10 hours. After salt water washing, the microencapsulated calcium alginate-distiller's grains biochar composite material is obtained after freezing and drying.
[0040] The upper layer of the gradient filtration unit 1 is filled with 1mm manganese sand filter material, and the lower layer is filled with 0.5mm quartz sand; the anodes of the low-voltage electrolytic cell 2 and the high-voltage electrolytic cell 3 are both filled with coal gangue modified straw biochar material, and the cathodes are both filled with microencapsulated calcium alginate-distiller's grains biochar composite material.
[0041] During operation, the following strategies are used to apply potential respectively: Strategy 1: 3V potential is applied to the low-voltage electrolytic cell 2, and 6V potential is applied to the high-voltage electrolytic cell 3; Strategy 2: 4V potential is applied to the low-voltage electrolytic cell 2, and 7V potential is applied to the high-voltage electrolytic cell 3; Strategy 3: 5V potential is applied to the low-voltage electrolytic cell 2, and 8V potential is applied to the high-voltage electrolytic cell 3.
[0042] As shown in Figures 2-3 , the system of the present application is used to treat intercooling water, and under strategy 1, strategy 2 and strategy 3, the removal rates of SO4 2- by the electrochemical equipment are 81.60%, 93.60% and 94.40% respectively, and the removal rates of Fe 3+ are 88.67%, 97.50% and 99.83% respectively. It can be seen that the system of the present application has good treatment effect on intercooling water. Among them, strategy 3, i.e. 5V potential is applied to the low-voltage electrolytic cell 2, and 8V potential is applied to the high-voltage electrolytic cell 3, has the best treatment effect.
[0043] Example 2 Straw was crushed to 80 mesh, pyrolyzed at 800°C under anaerobic conditions for 2 hours to obtain straw biochar. Coal gangue was crushed and ball-milled to powder for 2 hours, then mixed with straw biochar at a mass ratio of 2:5, pyrolyzed at 800°C under anaerobic conditions for 2 hours. After cooling, it was soaked in 1 mol / L dilute hydrochloric acid solution for 48 hours, washed to neutral, and dried to obtain coal gangue modified straw biochar material.
[0044] Distiller's grains were dried at 60°C, ground into 1 mm fragments, and pyrolyzed at 300°C under anaerobic conditions for 2 hours to obtain distiller's grains biochar. A sodium alginate suspension with a mass concentration of 1.5% was mixed with distiller's grains biochar at a mass ratio of 3:1, and was dropped into a 0.1 mol / L calcium chloride solution at a rate of 10 mL / min, and solidified for 20 hours. After salt water washing, freezing and drying, a calcium alginate-distiller's grains biochar composite material was obtained.
[0045] The upper layer of the gradient filtration unit 1 was filled with 1 mm manganese sand filter material, and the lower layer was filled with 0.5 mm quartz sand; the anodes of the low-pressure electrolytic cell 2 and the high-pressure electrolytic cell 3 were both filled with coal gangue modified straw biochar material, and the cathodes were both filled with microencapsulated calcium alginate-distiller's grains biochar composite material.
[0046] Example 3 Straw was crushed to 90 mesh, pyrolyzed at 700°C under anaerobic conditions for 3 hours to obtain straw biochar. Coal gangue was crushed and ball-milled to powder for 4 hours, then mixed with straw biochar at a mass ratio of 2:5, pyrolyzed at 700°C under anaerobic conditions for 3 hours. After cooling, it was soaked in 1 mol / L dilute hydrochloric acid solution for 36 hours, washed to neutral, and dried to obtain coal gangue modified straw biochar material.
[0047] Distiller's grains were dried at 70°C, ground into 5 mm fragments, and pyrolyzed at 300°C under anaerobic conditions for 2 hours to obtain distiller's grains biochar. A sodium alginate suspension with a mass concentration of 0.5% was mixed with distiller's grains biochar at a mass ratio of 5:1, and was dropped into a 0.1 mol / L calcium chloride solution at a rate of 10 mL / min, and solidified for 20 hours. After salt water washing, freezing and drying, a calcium alginate-distiller's grains biochar composite material was obtained.
[0048] The upper layer of the gradient filtration unit 1 was filled with 1 mm manganese sand filter material, and the lower layer was filled with 0.5 mm quartz sand; the anodes of the low-pressure electrolytic cell 2 and the high-pressure electrolytic cell 3 were both filled with coal gangue modified straw biochar material, and the cathodes were both filled with microencapsulated calcium alginate-distiller's grains biochar composite material.
[0049] The above merely describes the preferred embodiments of the present application, and is not used to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.
Claims
1. A system for efficiently treating inter-cooling water by electrochemical method, characterized in that, It comprises a gradient filtration unit (1), a low-voltage electrolytic cell (2) and a high-voltage electrolytic cell (3); the bottom outlet of the gradient filtration unit (1) is connected with the bottom inlet of the low-voltage electrolytic cell (2); the top outlet of the low-voltage electrolytic cell (2) is connected with the top inlet of the high-voltage electrolytic cell (3); The gradient filtration unit (1) comprises a manganese sand layer (11) and a quartz sand layer (12) from top to bottom in sequence; The inside of the anode of the low-voltage electrolytic cell (2) and the high-voltage electrolytic cell (3) is filled with coal gangue modified straw biochar material, and the inside of the cathode is filled with microencapsulated calcium alginate-distiller's grains biochar composite material; the working voltage of the low-voltage electrolytic cell (2) is lower than that of the high-voltage electrolytic cell (3).
2. The system for efficiently treating intercooling water by electrochemical method according to claim 1, characterized in that, The volume ratio of the manganese sand layer (11) to the quartz sand layer (12) is 1: (1.5-2.0).
3. The system for efficiently treating intercooling water by electrochemical method according to claim 1, characterized in that, The particle size of the manganese sand layer (11) is 1-2 mm, and the particle size of the quartz sand layer (12) is 0.5 mm.
4. The system for efficiently treating intercooling water by electrochemical method according to claim 1, characterized in that, The working voltage of the low-voltage electrolytic cell (2) is 3-5 V, and the working voltage of the high-voltage electrolytic cell (3) is 6-8 V.
5. The system for efficiently treating intermediate cooling water using an electrochemical method according to claim 1, characterized in that, The preparation method of the coal gangue modified straw biochar material is as follows: The straw is crushed and pyrolyzed under anaerobic conditions to obtain straw biochar; The coal gangue is crushed and ball milled to obtain coal gangue powder; The coal gangue powder and the straw biochar are mixed and pyrolyzed under anaerobic conditions, and then the mixture is cooled, washed with acid, washed, and dried to obtain the coal gangue modified straw biochar material.
6. The system for efficiently treating intercooling water by electrochemical method according to claim 5, characterized in that, The mass ratio of the coal gangue powder to the straw biochar is 2:
5.
7. The system for efficiently treating intermediate cooling water using an electrochemical method according to claim 1, characterized in that, The preparation method of the microencapsulated calcium alginate-distiller's grains biochar composite material is as follows: The distiller's grains are dried, crushed, and pyrolyzed under anaerobic conditions to obtain distiller's grains biochar; The sodium alginate suspension and the distiller's grains biochar are mixed to obtain a mixed solution; the mixed solution is dropped into a CaCl2 solution for solidification reaction, and then washed, frozen, and dried to obtain the microencapsulated calcium alginate-distiller's grains biochar composite material.
8. The system for efficiently treating intercooling water by electrochemical method according to claim 7, characterized in that, The mass concentration of the sodium alginate suspension is 0.5%-1.5%, and the mass ratio of the sodium alginate suspension to the distiller's grains biochar is (3-5):
1.
9. A method for efficiently treating inter-cooling water by electrochemical method, characterized in that, The system according to any one of claims 1-8, comprising the following steps: The cold water in the treatment interval is introduced into the gradient filtration unit (1) and filtered through the manganese sand layer (11) and the quartz sand layer (12) in sequence to remove iron suspended solids; The filtered water is introduced into a low-voltage electrolytic cell (2) for primary electrolytic treatment to remove a portion of SO4 2- and Fe 3+ pollutants; The water treated by the low-voltage electrolytic cell (2) is introduced into the high-voltage electrolytic cell (3) for deep electrolytic treatment to remove residual SO4 2- , Fe 3+ pollutants and residual pollutants.
10. The method for efficiently treating intercooling water by electrochemical method according to claim 9, characterized in that, Further comprising: When the anode adsorption capacity decreases to 70%-75% of the initial value, backwashing regeneration is adopted; The backwashing parameters are: water flow rate 5-8 m / h, and duration 15-30 minutes; When the cathode adsorption capacity decreases to 70%-75% of the initial value, citric acid solution immersion regeneration is adopted; the immersion parameters are: citric acid solution concentration 0.5-1.0 mol / L, temperature 40-50℃, and time 2-4 hours.