A method and apparatus for target-selective electrodialysis driven by electrically coupled range-extended solar energy.

Abstract

This invention discloses an electrically coupled, range-extended, solar-driven, target-selective electrodialysis method and apparatus, relating to the field of clean energy-driven technology for drinking water treatment. The specific preparation method includes: configuring the electrodialysis device at the front end of a solar controller; in the trough region, the electrodialysis device functions as an energy storage battery, while in the peak region, it functions as a peak-shaving resistor to optimize system energy management. Through the selective action of the ion exchange membrane in the electrodialysis device, wastewater can be effectively desalinated without damaging the aqueous phase, reducing the load on subsequent treatment systems, while simultaneously recovering valuable salt resources for resource utilization. It is particularly suitable for areas with high solar radiation intensity, enabling the development and utilization of new energy sources and solving the problem of energy scarcity.

Description

Technical Field

[0001] This invention relates to the field of clean energy-driven technology for drinking water treatment, specifically to an electrically coupled range-extended solar-driven method and apparatus for target-selective electrodialysis. Background Technology

[0002] Drinking water quality issues vary from region to region. These issues require different methods for advanced treatment, including ozone-activated carbon methods, membrane separation methods, biological activated carbon methods, and stripping methods. Excessive pollutants include mineralization, total hardness, nitrates, nitrites, ammonia nitrogen, iron, manganese, chlorides, sulfates, pH, fluorides, and phenols. For low-concentration target ions such as fluorides, electrodialysis, as a membrane separation technology, is widely used. The electrodialysis process combines electrochemical and dialysis diffusion processes. Driven by an applied DC electric field, it utilizes the selective permeability of ion exchange membranes (i.e., cations can pass through cation exchange membranes, and anions can pass through anion exchange membranes), causing cations and anions to move towards the anode and cathode, respectively. During ion migration, if the fixed charge of the membrane is opposite to the charge of the ions, the ions can pass through; if their charges are the same, the ions are repelled, thus achieving the purpose of desalination, concentration, purification, or refining of the solution. In this invention, electrodialysis is coupled to a solar power system as an electrical component, and a clean, low-energy-consumption, and low-cost processing technology is developed to separate and recover target ions such as fluoride. This device realizes both energy utilization and desalination of drinking water. Summary of the Invention

[0003] The purpose of this invention is to provide an electrically coupled extended-range solar-driven target selective electrodialysis method and apparatus, which couples the electrodialysis device as an electrical component to a solar power supply system, thereby developing a clean, low-energy-consumption, and low-cost wastewater treatment process to solve water pollution problems.

[0004] To solve the above-mentioned technical problems, the present invention specifically provides the following technical solution:

[0005] This invention discloses an electrically coupled range-extended solar-driven target-selective electrodialysis device, comprising: a solar panel, an electrodialysis device, a solar controller, a storage battery, and a pump; the electrodialysis device is connected in series before the solar controller, and in the trough region, the electrodialysis device functions as an energy storage battery, while in the peak region, the electrodialysis device functions as a peak-suppression resistor.

[0006] Preferably, the electrodialysis device includes a cation exchange membrane and an anion exchange membrane. The anion exchange membrane is a homogeneous ion exchange membrane or a modified anion exchange membrane. The modified anion exchange membrane is prepared from polysulfone derivatives and chitosan derivatives. Introducing chitosan derivatives into the preparation of modified anion exchange membranes from polysulfone derivatives can effectively improve the performance of the anion exchange membrane, promote the formation of microphase separation structures within the membrane, thereby increasing the elongation at break and improving electrodialysis performance, namely desalination rate and current efficiency.

[0007] Preferably, the power supply voltage of the electrocoupled range-extended solar-driven target selectivity device is 6-24V, and the water production capacity is 20-200L / day.

[0008] Preferably, the peak voltage of the solar panel is the sum of the voltages of the battery and the electrodialysis device, and the peak power is the sum of the power of the battery and the electrodialysis device.

[0009] Preferably, in case of system emergency, the solar panels are replaced by a 220V transformer with a rated voltage of 6-24V.

[0010] Preferably, in the trough region, the solar controller with a voltage lower than the rated voltage is in the off state, supplying power only to the electrodialysis unit, while the pump requires a stable rated voltage supplied by the battery; in the peak region, the solar controller with a voltage higher than the rated voltage is in the connected state.

[0011] Preferably, the electrodialysis device has a rated voltage of 6-24V and a power of 1-6W.

[0012] Preferably, the battery has a rated voltage of 6-24V and an energy storage capacity of 1000-8000mAh, and the battery only supplies power to the pump at its rated power.

[0013] Preferably, the pump has a DC rated power and is used as a single pump or two pumps, a freshwater pump and a concentrated water pump, connected in parallel.

[0014] This invention discloses the application of the above-mentioned electrically coupled range-extended solar-driven target-selective electrodialysis device in a wastewater treatment device.

[0015] This invention discloses an electrically coupled range-extended solar-driven target-selective electrodialysis device, comprising: a solar panel, an electrodialysis unit, a solar controller, a battery, and a pump. The electrodialysis unit is connected in series before the solar controller to achieve intelligent energy distribution within the system. In the trough region, the electrodialysis unit functions as an energy storage battery; in the peak region, it functions as a peak-shaving resistor, achieving grid load balancing through efficient energy consumption. This enables intelligent energy distribution within the system.

[0016] Preferably, the electrically coupled range-extended solar-driven target selective electrodialysis device is a compact device suitable for small household applications, featuring both high efficiency and portability.

[0017] Preferably, the power supply voltage of the electrically coupled range-extended solar-driven target selectivity device is 6-24V. This low-voltage range design ensures the safety and applicability of the device, while also enabling it to be compatible with various residential solar power systems.

[0018] Preferably, the water production capacity of the electrically coupled range-extended solar-driven target-selective device is 20-200L / day, meeting the daily water purification needs of ordinary households.

[0019] Preferably, the electrodialysis unit is positioned before the solar controller to achieve intelligent energy distribution within the system. During periods of low grid load, when the solar output voltage is below the rated starting voltage of the solar controller, the solar controller is disconnected to avoid ineffective power loss, supplying power only to the electrodialysis unit. This fully utilizes intermittent solar output to achieve selective ion separation. The pump within the unit, a key operating component of the system, is supplied with a stable rated voltage via a battery to ensure continuous and reliable operation.

[0020] Preferably, the electrodialysis unit is positioned before the solar controller to achieve efficient utilization of solar energy resources and dynamic control of system energy flow. During peak periods of high grid load, when the solar output voltage exceeds the rated voltage of the solar controller, the solar controller enters a connected state, allowing solar power to preferentially charge the battery to store energy for subsequent use. Simultaneously, the portion of the solar output above the rated voltage is directly used to drive the target ion selective electrodialysis unit, achieving stratified utilization of electrical energy. The drive pump in the unit is powered by a stable voltage supplied by the battery to ensure pump operational reliability and overall system stability.

[0021] Preferably, a high-efficiency solar panel design is adopted, where the peak voltage is determined by the sum of the battery charging voltage and the electrodialysis device operating voltage, and the peak power is correspondingly the product of the battery charging voltage and the electrodialysis device operating voltage. By optimizing the electrical characteristics and load matching of the solar panels, the system significantly reduces the area requirement of the solar panels while achieving high-efficiency energy utilization, making its total area only 50% of that of traditional designs.

[0022] Preferably, the electrodialysis device has a rated voltage of 6-24V to accommodate fluctuations in solar voltage output. The power consumption is 1-6W, with the specific power consumption depending on the workload and actual solar input conditions.

[0023] Preferably, the solar controller is designed as a simple and efficient resistance peak-shaving controller, whose working principle is based on voltage switching control. When the solar input voltage exceeds the set rated voltage, the controller is in the "on" state, allowing electrical energy to pass through and supply the battery and electrodialysis unit, so as to make full use of excess solar power for storage and consumption. When the solar input voltage is lower than the rated voltage, the controller enters the "off" state, automatically disconnecting from the system to avoid energy waste or equipment instability caused by low voltage.

[0024] Preferably, the battery has a rated voltage of 6-24V and an energy storage capacity of 1000-8000mAh. The main function of the battery is to provide a stable power supply to the water pumps in the system, ensuring its output power remains within the rated power range to guarantee the normal operation of the pumps and the stability of the system. Compared to traditional batteries, this battery has a capacity that is only 1 / 10 to 1 / 5 that of traditional batteries.

[0025] Preferably, the pump is a DC-driven pump with a fixed rated power to ensure stable and efficient water delivery and circulation. Depending on system requirements, the pump can be configured as a single pump, suitable for smaller-scale applications, meeting daily water treatment and delivery needs. Alternatively, a parallel configuration of the freshwater pump and the concentrate pump can be used to handle larger-scale or more demanding water treatment tasks. This parallel configuration enables separate treatment and delivery of freshwater and concentrate, optimizes the system's energy efficiency ratio, and provides flexible load management, ensuring balanced output and meeting different water quality requirements under varying operating conditions.

[0026] Preferably, when the solar panel cannot supply power normally due to abnormal conditions, a 220V AC power supply is used as a backup energy input, and the voltage is converted to a rated 6-24V DC voltage through a transformer device.

[0027] Preferably, the pump power is 4-8W and the voltage is 10-15V.

[0028] Preferably, the solar panel specifications are 6-24V, 18-24W.

[0029] Preferably, the voltage of the solar controller is 10-15V.

[0030] Preferably, the electrodialysis device comprises a solar photovoltaic panel, an electrodialysis membrane stack, a membrane stack inlet, a membrane stack outlet, electrode plates, an ion exchange membrane, a power cord, conduits, an outlet tank, a feed tank, an electrode liquid tank, a positive electrode, and a negative electrode. By combining optimized parameters such as high current density and flow rate, it can achieve efficient separation and recovery of specific target ions, fluoride ions, and nitrate ions. The working principle is based on the electrodialysis process, utilizing an electric field to drive ions to migrate on the ion exchange membrane, thereby achieving effective separation between different ions. By adjusting the current density, fluid flow rate, and electric field strength, the migration rate and distribution of ions can be precisely controlled, thereby improving the recovery efficiency of target ions.

[0031] This invention discloses an electrodialysis device, specifically:

[0032] An electrodialysis system includes a power supply, a flow meter, an electrodialysis membrane stack, a circulation pump, and a water tank. The electrodialysis membrane stack includes an anode plate, a separator, an anion plate, and membrane units.

[0033] Preferably, the separator is a separator commonly used in the field of electrodialysis.

[0034] Preferably, the anode plate and the cathode plate are respectively disposed at both ends of the membrane stack, with the anode plate connected to the positive terminal of the power supply and the cathode plate connected to the negative terminal of the power supply.

[0035] Preferably, the membrane unit is located between the anode plate and the cathode plate, and sequentially includes an anion exchange membrane and a repeating unit membrane from the anode plate to the cathode plate.

[0036] More preferably, in the repeating unit membrane, the unit membranes formed by cation exchange membranes and anion exchange membranes are repeatedly arranged, and the number of repeating unit membranes is 2-20.

[0037] Preferably, the anode plate, membrane stack, and cathode plate are arranged in a series of alternating anode chambers, repeating unit chambers, and cathode chambers. The repeating unit chambers are repeating unit chambers formed by dilute and concentrated chambers, and the number of repeating unit chambers corresponds to the number of repeating unit membranes.

[0038] Preferably, the electrode chamber water tank is connected to the electrode chamber via a conduit, allowing the electrode solution to flow sequentially from the electrode chamber water tank into the cathode chamber, then into the anode chamber, and finally back into the electrode chamber water tank. The concentrate chamber water tank is connected to the inlet and outlet of the concentrate chamber via a conduit, allowing the concentrate to flow sequentially from the concentrate chamber water tank into the electrodialysis membrane stack and then back into the concentrate chamber water tank. The dilute chamber water tank is connected to the inlet and outlet of the dilute chamber via a conduit, allowing the dilute chamber water to flow sequentially into the electrodialysis membrane stack and then back into the dilute chamber water tank. Preferably, the ion exchange membrane includes a cation exchange membrane and an anion exchange membrane.

[0039] More preferably, the cation exchange membrane is a homogeneous ion exchange membrane, and the anion exchange membrane is a homogeneous ion exchange membrane or a modified anion exchange membrane.

[0040] This invention discloses a method for preparing epoxy-based ammonium chloride, specifically:

[0041] 2-(2-(chloromethyl)phenyl)ethylene oxide was mixed with a trimethylamine acetone solution and reacted at 8-15℃ for 5-10 h. After the reaction was completed, the mixture was washed and dried to obtain epoxy ammonium chloride.

[0042] Preferably, the trimethylamine acetone solution is composed of trimethylamine and acetone, and the ratio of trimethylamine to acetone is 1 mol: 480-550 ml.

[0043] Preferably, the ratio of 2-(2-(chloromethyl)phenyl)ethylene oxide to trimethylamine acetone solution is 1 mol: 500-600 ml.

[0044] Preferably, the washing reagent is acetone.

[0045] This invention discloses a method for preparing a polysulfone derivative, specifically:

[0046] N,N,N,N-Tetramethyl-1,6-hexanediamine was mixed with ethyl acetate, and then an iodomethane solution was added. The mixture was reacted at 30°C for 6 h. After the reaction, ethyl acetate was added to wash the product to obtain an intermediate. Polysulfone, chloromethyl octyl ether, and tin tetrachloride were added to dichloromethane and reacted at 30-40°C for 25-40 min. After the reaction, ethanol was added to separate the precipitate, which was then dried to obtain chloromethyl polysulfone. Chloromethyl polysulfone and the intermediate were added to N-methyl-2-pyrrolidone and reacted at 70-80°C for 40-55 h. After the reaction, ethyl acetate was added to precipitate the precipitate, which was then washed and dried to obtain the polysulfone derivative.

[0047] Preferably, the volume ratio of N,N,N,N-tetramethyl-1,6-hexanediamine to ethyl acetate is 1:0.8-1.2.

[0048] Preferably, the iodomethane solution is composed of iodomethane and ethyl acetate, and the volume ratio of iodomethane to ethyl acetate used is 1:15-19.

[0049] Preferably, the volume ratio of N,N,N,N-tetramethyl-1,6-hexanediamine to iodomethane solution is 1:0.8-1.2.

[0050] Preferably, the ratio of polysulfone to chloromethyl octyl ether is 1g: 5-10ml.

[0051] Preferably, the ratio of polysulfone to tin tetrachloride is 1g:0.1-0.5ml.

[0052] Preferably, the ratio of polysulfone to dichloromethane is 1g:40-60ml.

[0053] Preferably, the ratio of chloromethyl polysulfone to N-methyl-2-pyrrolidone is 1g:5-15ml.

[0054] Preferably, the mass ratio of chloromethyl polysulfone to the intermediate is 1:1-2.

[0055] This invention discloses a method for preparing chitosan derivatives, specifically:

[0056] Water and acetic acid were added to chitosan, and epoxy ammonium chloride was added under nitrogen conditions. The mixture was reacted at 60-70℃ for 20-30 h. After the reaction was completed, the precipitate was separated by adding the precipitate solution, and the precipitate was washed and dried to obtain the chitosan derivative.

[0057] Preferably, the ratio of chitosan to water is 1g:50-70ml.

[0058] Preferably, the ratio of chitosan to acetic acid is 1g:0.3-0.8ml.

[0059] Preferably, the mass ratio of chitosan to epoxy ammonium chloride is 1:4-5.

[0060] Preferably, the precipitate is composed of acetone and ethanol, and the volume ratio of acetone to ethanol is 1:0.8-1.2.

[0061] This invention discloses a method for preparing a modified anion exchange membrane, specifically as follows:

[0062] A chitosan derivative solution was obtained by adding water and acetic acid to a chitosan derivative, and a polysulfone derivative solution was obtained by adding N-methyl-2-pyrrolidone to a polysulfone derivative. The chitosan derivative solution and the polysulfone derivative solution were mixed, poured into a glass plate, heated at 55-65℃ for 20-30 hours, and then peeled off to obtain a modified anion exchange membrane.

[0063] Preferably, the ratio of chitosan derivative to added water is 1g:50-65ml, and the ratio of chitosan to added acetic acid is 1g:0.3-0.8ml.

[0064] Preferably, the ratio of polysulfone derivative to added N-methyl-2-pyrrolidone is 1g:10-20ml.

[0065] Preferably, the mass ratio of the polysulfone derivative to the chitosan derivative is 1:0.1-0.7.

[0066] More preferably, in the preparation of the modified anion exchange membrane, in addition to using epoxy-ammonium chloride to prepare chitosan derivatives and further preparing the modified anion exchange membrane, sodium 2,3-epoxypropane-1-sulfonate can also be used. Using sodium 2,3-epoxypropane-1-sulfonate to synergistically prepare chitosan derivatives and then using them to prepare the modified anion exchange membrane can further modify and improve the micromorphology and electrodialysis performance of the modified anion exchange membrane, thereby further improving the desalination rate, current efficiency, and elongation at break.

[0067] Preferably, the mass ratio of the amount of epoxy ammonium chloride to sodium 2,3-epoxypropane-1-sulfonate is 1:0.1-0.9.

[0068] Compared with the prior art, the present invention has the following advantages:

[0069] This invention proposes an electrically coupled, range-extended, solar-driven, target-selective electrodialysis method and apparatus. By configuring the electrodialysis device at the front end of the solar controller, it functions as an "energy storage battery" in the trough region and as a "peak-suppression resistor" in the peak region to optimize system energy management. Through the selective action of the ion exchange membrane in the electrodialysis device, wastewater can be effectively desalinated without damaging the aqueous phase, reducing the load on subsequent treatment systems. Simultaneously, valuable salt resources are recovered, achieving resource utilization. The separation and recovery rate of target ions can reach 80%–90%, effectively solving the problems of excessive ion content in groundwater and water scarcity. It is particularly suitable for areas with high solar radiation intensity, developing and utilizing new energy sources, and solving the problem of energy shortage. Attached Figure Description

[0070] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0071] Figure 1 System diagram and daily photovoltaic power generation diagram of target-selective electrodialysis technology and device driven by electric-coupled range-extended solar energy;

[0072] Figure 2 The diagram shows the system operation in the trough area and the daily power generation in the photovoltaic trough area.

[0073] Figure 3 The system operation diagram and the daily power generation diagram of the photovoltaic peak zone are shown.

[0074] Figure 4This is a structural diagram of an electrodialysis device. Detailed Implementation

[0075] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0076] The concepts involved in this application will first be described with reference to the accompanying drawings. It should be noted that the following descriptions of various concepts are only for the purpose of making the content of this application easier to understand and do not constitute a limitation on the scope of protection of this application; furthermore, the embodiments and features in the embodiments of this application can be combined with each other unless otherwise specified. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0077] An electrically coupled range-extended solar-driven target-selective electrodialysis device, such as Figure 4 As shown, it includes: 1. Solar photovoltaic panel, 2. Electrodialysis membrane stack, 3. Membrane stack inlet, 4. Membrane stack outlet, 5. Electrode plate, 6. Ion exchange membrane, 7. Power line, 8. Conduit, 9. Discharge tank, 10. Feed tank, 11. Electrolyte tank, 12. Positive electrode, 13. Negative electrode.

[0078] Example 1:

[0079] Electrodialysis apparatus: An electrodialysis system, comprising a power supply, a flow meter, an electrodialysis membrane stack, a circulating pump, and a water tank. The electrodialysis membrane stack includes an anode plate, a separator, an anion plate, and membrane units. The separator is the type commonly used in the field of electrodialysis. The anode and anion plates are respectively located at both ends of the membrane stack; the anode plate is connected to the positive terminal of the power supply, and the anion plate is connected to the negative terminal. The membrane units are located between the anode and anion plates, and from the anode plate to the anion plate, they sequentially include anion exchange membranes and repeating unit membranes; in the repeating unit membranes, unit membranes formed by cation exchange membranes and anion exchange membranes are arranged repeatedly, with a repeating unit membrane number of 2. The anode plate, membrane stack, and anion plate alternately form an anode chamber, a repeating unit chamber, and a cathode chamber. The repeating unit chamber is a repeating unit chamber formed by a dilute chamber and a concentrated chamber, and the number of repeating unit chambers corresponds to the number of repeating unit membranes. The electrode chamber water tank is connected to the electrode chambers via conduits, allowing the electrode solution to flow sequentially from the electrode chamber water tank into the cathode chamber, then into the anode chamber, and finally back into the electrode chamber water tank. The concentrate chamber water tank is connected to the inlet and outlet of the concentrate chamber via conduits, allowing the concentrate to flow sequentially from the concentrate chamber water tank into the electrodialysis membrane stack and then back into the concentrate chamber water tank. The dilute chamber water tank is connected to the inlet and outlet of the dilute chamber via conduits, allowing the dilute chamber water to flow sequentially into the electrodialysis membrane stack and then back into the dilute chamber water tank. Both the cation exchange membrane and the anion exchange membrane are homogeneous ion exchange membranes.

[0080] Electrocoupled Range Extender Solar-Driven Target-Selective Electrodialysis Unit: A 18V, 20W solar panel converts solar energy into electrical energy and transmits it to the system via connecting lines. The panel is connected to the electrodialysis unit for analyzing and distributing solar power output; it acts as a storage battery in the trough area and a peak-shaving resistor in the peak area. A 12V solar controller is responsible for delivering the power from the solar panel to the battery. Current flows through the solar controller, which regulates and manages the current to ensure stability and protect the entire system. In the trough area, the solar controller is disconnected when the voltage is below the rated value; in the peak area, it is connected when the voltage is above the rated value. A 12V battery stores the electrical energy generated by the solar panel for use at night or on cloudy days when the photovoltaic panel's power generation is insufficient. It is connected to the system via the controller and includes a fuse for additional safety protection. Two water pumps, Pump I and Pump II, each with a power of 6W and a voltage of 12V, are powered by the battery and can be used for pumping water or other applications.

[0081] Example 2:

[0082] The electrodialysis device is the same as in Example 1.

[0083] Electrocoupled Range Extender Solar-Driven Target-Selective Electrodialysis Unit: A 18V, 20W solar panel converts solar energy into electrical energy and transmits it to the system via connecting lines. The panel is connected to the electrodialysis unit for analyzing and distributing solar power output; it acts as a storage battery in the trough area and a peak-shaving resistor in the peak area. A 12V solar controller is responsible for delivering power from the solar panel to the battery. Current flows through the solar controller, which regulates and manages the current to ensure stability and protect the entire system. In the trough area, the solar controller is disconnected when the voltage is below the rated value; in the peak area, it is connected when the voltage is above the rated value. A 6V battery stores the electrical energy generated by the solar panel for use at night or on cloudy days when the photovoltaic panel output is insufficient. It is connected to the system via the controller and includes a fuse for additional safety protection. Two water pumps, designated "Pump I" and "Pump II," each with a power of 6W and a voltage of 12V, are powered by the battery and can be used for pumping water or other applications.

[0084] Example 3:

[0085] The electrodialysis device is the same as in Example 1.

[0086] Electrocoupled Range Extender Solar-Driven Target-Selective Electrodialysis Unit: A 18V, 20W solar panel converts solar energy into electrical energy and transmits it to the system via connecting wires. The panel is connected to the electrodialysis unit for analyzing and distributing solar power output; it acts as a storage battery in the trough area and a peak-shaving resistor in the peak area. A 12V solar controller is responsible for delivering the power from the solar panel to the battery. Current flows through the solar controller, which regulates and manages the current to ensure stability and protect the entire system. In the trough area, the solar controller is disconnected when the voltage is below the rated value; in the peak area, it is connected when the voltage is above the rated value. A 12V battery stores the electrical energy generated by the solar panel for use at night or on cloudy days when the photovoltaic panel output is insufficient. It is connected to the system via the controller and includes a fuse for additional safety protection. A 6W, 12V water pump is powered by the battery and can be used for pumping water or other applications.

[0087] Example 4:

[0088] The electrodialysis device is the same as in Example 1.

[0089] The electrically coupled range-extended solar-driven target-selective electrodialysis unit utilizes a 220V transformer to provide power. An inverter on the connecting line converts AC to DC power for transmission to the system. Solar panels are connected to the electrodialysis unit to analyze and distribute solar power output. In the trough areas, the panels act as energy storage batteries, while in the peak areas, they function as peak-shaving resistors. A 12V solar controller is responsible for transmitting power from the solar panels to the batteries. Current flows through the solar controller, which regulates and manages the current to ensure stability and protect the entire system. In trough areas, the solar controller is disconnected when the voltage is below the rated value; in peak areas, it is connected when the voltage is above the rated value. A 12V battery stores the power generated by the solar panels for use at night or on cloudy days when photovoltaic power generation is insufficient. It is connected to the system via the controller and includes a fuse for additional safety protection. Two water pumps, designated "Pump I" and "Pump II," each have a power of 6W and operate at 12V. The water pump draws power from a battery, and two pumps can be used for pumping water or other applications when in operation.

[0090] Example 5:

[0091] Preparation of epoxy-based ammonium chloride: 2-(2-(chloromethyl)phenyl)epoxide was mixed with a trimethylamine acetone solution and reacted at 10°C for 6 h. After the reaction, the mixture was washed with acetone and dried to obtain epoxy-based ammonium chloride. The trimethylamine acetone solution consisted of trimethylamine and acetone in a ratio of 1 mol:500 ml, and the ratio of 2-(2-(chloromethyl)phenyl)epoxide to the trimethylamine acetone solution was 1 mol:550 ml.

[0092] Preparation of polysulfone derivatives: N,N,N,N-tetramethyl-1,6-hexanediamine was mixed with ethyl acetate, and then iodomethane solution was added and reacted at 30°C for 6 h. After the reaction, ethyl acetate was added to wash the mixture to obtain an intermediate. Polysulfone, chloromethyl octyl ether, and tin tetrachloride were added to dichloromethane and reacted at 35°C for 30 min. After the reaction, ethanol was added to separate the precipitate, which was then washed and dried to obtain chloromethyl polysulfone. Chloromethyl polysulfone and the intermediate were added to N-methyl-2-pyrrolidone and reacted at 75°C for 48 h. After the reaction, ethyl acetate was added to precipitate the precipitate, which was then washed and dried to obtain the polysulfone derivative. The volume ratio of N,N,N,N-tetramethyl-1,6-hexanediamine to ethyl acetate is 1:1; the iodomethane solution consists of iodomethane and ethyl acetate, with a volume ratio of iodomethane to ethyl acetate of 1:16.67; the volume ratio of N,N,N,N-tetramethyl-1,6-hexanediamine to iodomethane solution is 1:1.06; the ratio of polysulfone to chloromethyl octyl ether is 1 g:6 ml; the ratio of polysulfone to tin tetrachloride is 1 g:0.3 ml; the ratio of polysulfone to dichloromethane is 1 g:50 ml; the ratio of chloromethyl polysulfone to N-methyl-2-pyrrolidone is 1 g:10 ml; and the mass ratio of chloromethyl polysulfone to the intermediate is 1:1.72.

[0093] Preparation of chitosan derivatives: Water and acetic acid were added to chitosan to obtain a solution. Epoxy ammonium chloride was added to the solution under nitrogen atmosphere and reacted at 65°C for 24 hours. After the reaction, a precipitate was added to separate the precipitate, which was then washed with ethanol and dried to obtain the chitosan derivative. The ratio of chitosan to water was 1 g:60 ml, the ratio of chitosan to acetic acid was 1 g:0.5 ml, and the mass ratio of chitosan to epoxy ammonium chloride was 1:4.5. The precipitate consisted of acetone and ethanol, with a volume ratio of acetone to ethanol of 1:1.

[0094] Preparation of modified anion exchange membrane: A chitosan derivative solution was obtained by adding water and acetic acid to a chitosan derivative solution, and a polysulfone derivative solution was obtained by adding N-methyl-2-pyrrolidone to a polysulfone derivative solution. The chitosan derivative solution and the polysulfone derivative solution were mixed, poured into a glass plate, heated at 60℃ for 24 h, and then peeled off to obtain the modified anion exchange membrane. The ratio of chitosan derivative to water was 1 g:60 ml, the ratio of chitosan to acetic acid was 1 g:0.5 ml, the ratio of polysulfone derivative to N-methyl-2-pyrrolidone was 1 g:15 ml, and the mass ratio of polysulfone derivative to chitosan derivative was 1:0.35.

[0095] Electrodialysis device: The electrodialysis device in this embodiment differs from that in Example 1 in that the anion exchange membrane is a modified anion exchange membrane prepared in this embodiment, while other conditions and parameters are the same as in Example 1.

[0096] Electrocoupled range-extended solar-driven target selective electrodialysis device: The difference between the electrodialysis device in this embodiment and that in embodiment 1 is that the electrodialysis device is the same as that in embodiment 1, while the other conditions and parameters are the same as in embodiment 1.

[0097] Example 6:

[0098] The preparation of epoxy-based ammonium chloride is the same as in Example 5.

[0099] The preparation of polysulfone derivatives is the same as in Example 5.

[0100] Example 5: Preparation of chitosan derivatives.

[0101] Preparation of modified anion exchange membrane: The preparation of modified anion exchange membrane in this embodiment differs from that in Example 5 in that the mass ratio of polysulfone derivative to chitosan derivative is 1:0.6, while other conditions and parameters are the same as in Example 5.

[0102] Electrodialysis device: The electrodialysis device in this embodiment differs from that in Example 5 in that the anion exchange membrane is a modified anion exchange membrane prepared in this embodiment, while other conditions and parameters are the same as in Example 5.

[0103] Electrocoupled range-extended solar-driven target selective electrodialysis device: The difference between the electrodialysis device in this embodiment and that in embodiment 5 is that the electrodialysis device is the same as that in this embodiment, while the other conditions and parameters are the same as in embodiment 5.

[0104] Example 7:

[0105] The preparation of epoxy-based ammonium chloride is the same as in Example 5.

[0106] The preparation of polysulfone derivatives is the same as in Example 5.

[0107] Example 5: Preparation of chitosan derivatives.

[0108] Preparation of modified anion exchange membrane: The preparation of modified anion exchange membrane in this embodiment differs from that in Example 5 in that the mass ratio of polysulfone derivative to chitosan derivative is 1:0.2, while other conditions and parameters are the same as in Example 5.

[0109] Electrodialysis device: The electrodialysis device in this embodiment differs from that in Example 5 in that the anion exchange membrane is a modified anion exchange membrane prepared in this embodiment, while other conditions and parameters are the same as in Example 5.

[0110] Electrocoupled range-extended solar-driven target selective electrodialysis device: The difference between the electrodialysis device in this embodiment and that in embodiment 5 is that the electrodialysis device is the same as that in this embodiment, while the other conditions and parameters are the same as in embodiment 5.

[0111] Example 8:

[0112] The preparation of epoxy-based ammonium chloride is the same as in Example 5.

[0113] The preparation of polysulfone derivatives is the same as in Example 5.

[0114] Preparation of chitosan derivatives: Water and acetic acid were added to chitosan to obtain a solution. Epoxy ammonium chloride and sodium 2,3-epoxypropane-1-sulfonate were added to the solution under nitrogen atmosphere. The reaction was carried out at 65°C for 24 hours. After the reaction, a precipitate was added to separate the precipitate, which was then washed with ethanol and dried to obtain the chitosan derivative. The ratio of chitosan to water was 1 g:60 ml, the ratio of chitosan to acetic acid was 1 g:0.5 ml, the mass ratio of chitosan to epoxy ammonium chloride was 1:4.5, and the mass ratio of chitosan to sodium 2,3-epoxypropane-1-sulfonate was 1:1. The precipitate consisted of acetone and ethanol, with a volume ratio of acetone to ethanol of 1:1.

[0115] Preparation of modified anion exchange membrane: The preparation of modified anion exchange membrane in this embodiment differs from that in Example 5 in that the chitosan derivative is the chitosan derivative prepared in this embodiment, while other conditions and parameters are the same as in Example 5.

[0116] Electrodialysis device: The electrodialysis device in this embodiment differs from that in Example 5 in that the anion exchange membrane is a modified anion exchange membrane prepared in this embodiment, while other conditions and parameters are the same as in Example 5.

[0117] Electrocoupled range-extended solar-driven target selective electrodialysis device: The difference between the electrodialysis device in this embodiment and that in embodiment 5 is that the electrodialysis device is the same as that in this embodiment, while the other conditions and parameters are the same as in embodiment 5.

[0118] Comparative Example 1:

[0119] The preparation of epoxy-based ammonium chloride is the same as in Example 5.

[0120] The preparation of polysulfone derivatives is the same as in Example 5.

[0121] Example 5: Preparation of chitosan derivatives.

[0122] Preparation of modified anion exchange membrane: The preparation of modified anion exchange membrane in this embodiment differs from that in Example 5 in that the mass ratio of polysulfone derivative to chitosan derivative is 1:0.03, while other conditions and parameters are the same as in Example 5.

[0123] Electrodialysis device: The electrodialysis device in this embodiment differs from that in Example 5 in that the anion exchange membrane is a modified anion exchange membrane prepared in this embodiment, while other conditions and parameters are the same as in Example 5.

[0124] Electrocoupled range-extended solar-driven target selective electrodialysis device: The difference between the electrodialysis device in this embodiment and that in embodiment 5 is that the electrodialysis device is the same as that in this embodiment, while the other conditions and parameters are the same as in embodiment 5.

[0125] Experimental Example 1:

[0126] The desalination rate of the electrodialysis device was measured. Sodium chloride solution was used as the feed water to the dilute chamber in the dilute chamber water tank, ultrapure water was used as the feed water to the concentrate chamber in the concentrate chamber water tank, and sodium sulfate solution was used as the feed water to the electrode chamber in the electrode chamber water tank. The solutions were injected into the membrane stack, desalinated via electrodialysis, and then recycled back to the water tanks. The amount of mineralization removed from the sodium chloride solution in the dilute chamber by the electrodialysis device was expressed as the desalination rate: Desalination rate = (Initial conductivity of sodium chloride solution - Conductivity of sodium chloride solution after electrodialysis running time t) / Initial conductivity of sodium chloride solution × 100%. The sodium chloride solution consisted of sodium chloride and water, with a mass ratio of 1g:275ml. The sodium sulfate solution consisted of sodium sulfate and water, with a mass ratio of 1g:70.42ml. The operating voltage was 6V, the running time was 3h, and the sodium chloride solution flow rate was 30L / h. The electrodialysis device used was the same as those in Examples 1-8 and Comparative Example 1.

[0127] Table 1. Results of desalination rate determination

[0128]

[0129] The results are shown in Table 1. The desalination rate of the electrodialysis device in Example 5 was higher than that in Example 1, indicating that the modified anion exchange membrane prepared in Example 5 resulted in a higher desalination rate and better performance. Compared with Example 6, Example 5 showed that increasing the amount of chitosan derivative used within a certain range could effectively improve the performance of the prepared modified anion exchange membrane, thereby increasing the desalination rate of the electrodialysis device. Compared with Example 7, Example 5 showed that decreasing the amount of chitosan derivative used within a certain range would reduce the performance of the prepared modified anion exchange membrane, thereby reducing the desalination rate of the electrodialysis device. Compared with Example 8, Example 5 showed that further modification of the prepared chitosan derivative with sodium 2,3-epoxypropane-1-sulfonate based on the use of epoxy ammonium chloride, and its use in preparing the modified anion exchange membrane, could effectively improve the final desalination rate of the electrodialysis device. Compared with Comparative Example 1, Example 5 showed that the amount of chitosan derivative used needs to be within a suitable range; too low an amount would reduce the efficiency of the prepared modified anion exchange membrane, thus having no significant effect on improving the desalination rate of the electrodialysis device.

[0130] Experimental Example 2:

[0131] The current efficiency of the electrodialysis device was measured. Since ion exchange membranes are not ideally selectively permeable membranes (i.e., cation exchange membranes can permeate a small amount of anions, and anion exchange membranes can permeate a small amount of cations), and factors such as excessive operating voltage or current leading to water electrolysis, and leakage in the device, the actual number of moles of electrolyte precipitated during the desalination process deviates from the Faraday charge. Current efficiency is used to represent the magnitude of this deviation. Current efficiency = Faraday constant × solution flow rate (initial sodium chloride solution concentration - sodium chloride solution concentration after electrodialysis) / (number of membrane pairs in the electrodialysis membrane stack × electrodialysis operating current) × 100%. The operating voltage was 6V, the operating time was 3h, the sodium chloride solution flow rate was 30L / h, and the electrodialysis device used was the same as those in Examples 1-8 and Comparative Example 1.

[0132] Table 2 Results of current efficiency measurement

[0133]

[0134] The results are shown in Table 2. The current efficiency of the electrodialysis device in Example 5 is higher than that in Example 1, indicating that the modified anion exchange membrane prepared in Example 5 results in a higher current efficiency and better performance of the electrodialysis device. Compared with Example 6, Example 5 shows that increasing the amount of chitosan derivative within a certain range can effectively improve the performance of the prepared modified anion exchange membrane, thereby improving the current efficiency of the electrodialysis device. Compared with Example 7, Example 5 shows that decreasing the amount of chitosan derivative within a certain range will reduce the performance of the prepared modified anion exchange membrane, thereby reducing the current efficiency of the electrodialysis device. Compared with Example 8, Example 5 shows that further modification of the prepared chitosan derivative with sodium 2,3-epoxypropane-1-sulfonate based on the use of epoxy ammonium chloride, and its use in preparing the modified anion exchange membrane, can effectively improve the current efficiency of the final electrodialysis device. Compared with Comparative Example 1, Example 5 shows that the amount of chitosan derivative used needs to be within a suitable range; too low an amount will reduce the efficiency of the prepared modified anion exchange membrane, thus having no significant effect on improving the current efficiency of the electrodialysis device.

[0135] Experimental Example 3:

[0136] Mechanical properties and elongation at break were measured at 25°C and a tensile speed of 5 mm / min. The ion exchange membranes were the anion exchange membranes of Examples 1-4 and the modified anion exchange membranes of Examples 5-8 and Comparative Example 1.

[0137] Table 3 Results of Elongation at Break

[0138]

[0139] The results are shown in Table 3. The elongation at break of the modified anion exchange membrane in Example 5 is higher than that in Example 1, indicating that the modified anion exchange membrane prepared in Example 5 has better flexibility and meets the requirements of electrodialysis. Compared with Example 6, Example 5 shows that increasing the amount of chitosan derivative used within a certain range can effectively improve the flexibility of the modified anion exchange membrane. Compared with Example 7, Example 5 shows that decreasing the amount of chitosan derivative used within a certain range will reduce the flexibility of the modified anion exchange membrane. Compared with Example 8, Example 5 shows that using sodium 2,3-epoxypropane-1-sulfonate to further modify and prepare chitosan derivatives based on epoxy ammonium chloride, and using them to prepare modified anion exchange membranes, can effectively improve the flexibility of the modified anion exchange membranes. Compared with Comparative Example 1, Example 5 shows that the amount of chitosan derivative used needs to be within a suitable range; too low a amount will cause a decrease in the flexibility of the prepared modified anion exchange membrane.

[0140] The embodiments and / or implementation methods described above are merely preferred embodiments and / or implementation methods for implementing the technology of the present invention, and are not intended to limit the implementation methods of the technology of the present invention in any way. Any person skilled in the art can make some modifications or alterations to other equivalent embodiments without departing from the scope of the technical means disclosed in the content of the present invention, but they should still be regarded as the technology or embodiments that are substantially the same as the present invention.

[0141] This document uses specific examples to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this application. The above descriptions are only preferred embodiments of this application. It should be noted that due to the limitations of written expression, while there are objectively infinite specific structures, those skilled in the art can make several improvements, modifications, or changes without departing from the principles of this application, and can also combine the above technical features in an appropriate manner. These improvements, modifications, changes, or combinations, or the direct application of the inventive concept and technical solution to other situations without modification, should all be considered within the scope of protection of this application.

Claims

1. An electrically coupled range-extended solar-driven target-selective electrodialysis device, comprising: Solar panels, an electrodialysis device, a solar controller, a storage battery, and a pump; the electrodialysis device is connected in series before the solar controller, and in the trough region, the electrodialysis device functions as an energy storage battery, while in the peak region, the electrodialysis device functions as a peak-suppressing resistor; In the trough region, the solar controller with a voltage lower than the rated voltage is in the off state, supplying power only to the electrodialysis unit, while the pump requires a stable rated voltage supplied by the battery; in the peak region, the solar controller with a voltage higher than the rated voltage is in the connected state, and the solar power prioritizes charging the battery, while the battery supplies power to the pump only at its rated power.

2. The electrically coupled range-extended solar-driven target-selective electrodialysis device according to claim 1, characterized in that, The electrodialysis device includes a cation exchange membrane and an anion exchange membrane. The anion exchange membrane is a homogeneous ion exchange membrane or a modified anion exchange membrane. The modified anion exchange membrane is prepared from polysulfone derivatives and chitosan derivatives.

3. The electrically coupled range-extended solar-driven target-selective electrodialysis device according to claim 1, characterized in that, The electrically coupled range-extended solar-driven target selective electrodialysis device has a power supply voltage of 6-24V and a water production capacity of 20-200L / day.

4. The electrically coupled range-extended solar-driven target-selective electrodialysis device according to claim 1, characterized in that, The peak voltage of the solar panel is the sum of the voltages of the battery and the electrodialysis device, and the peak power is the sum of the power of the battery and the electrodialysis device.

5. The electrically coupled range-extended solar-driven target-selective electrodialysis device according to claim 1, characterized in that, In case of emergency, the solar panels can be replaced by a 220V transformer with a rated voltage of 6-24V.

6. The electrically coupled range-extended solar-driven target-selective electrodialysis device according to claim 1, characterized in that, The electrodialysis device has a rated voltage of 6-24V and a power of 1-6W.

7. The electrically coupled range-extended solar-driven target-selective electrodialysis device according to claim 1, characterized in that, The battery has a rated voltage of 6-24V and an energy storage capacity of 1000-8000mAh.

8. The electrically coupled range-extended solar-driven target-selective electrodialysis device according to claim 1, characterized in that, The pump is a DC rated power pump, and can be used as a single pump or two pumps, a freshwater pump and a concentrated water pump, connected in parallel.

9. The application of the electrically coupled range-extended solar-driven target selective electrodialysis device according to any one of claims 1-8 in a wastewater treatment device.

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