A device and method for in-situ remediation of saline soil based on electro-osmosis-elysion synergy
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- SOUTHWEST PETROLEUM UNIV
- Filing Date
- 2026-04-13
- Publication Date
- 2026-06-09
Smart Images
Figure CN122164741A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the interdisciplinary field of geotechnical engineering and environmental engineering, and specifically relates to a device and method for in-situ remediation of saline soil based on electroosmosis-leaching synergistic remediation. Background Technology
[0002] Saline soil (alkaline soil) is a widely distributed low-yield soil type globally, especially in arid, semi-arid, and coastal areas, covering vast areas and posing a major obstacle to agricultural production and ecological restoration. Traditional saline soil remediation methods mainly include engineering measures (such as drainage and salt leaching, and soil replacement) and chemical amendments (such as the application of gypsum, ferrous sulfate, and organic materials). However, these methods generally suffer from problems such as high water consumption, long remediation cycles, difficulty in removing deep salts, and a tendency to cause secondary salinization or salt rebound in groundwater.
[0003] The simple leaching method dissolves and washes salts downwards by irrigating with fresh water. It is easy to operate and has a low cost. However, it is not very effective for low-permeability clay saline soils, requires a large amount of fresh water, and the salt migration is not directional, making it difficult to completely remove deep salts. Long-term use may aggravate groundwater salt pollution.
[0004] Electroosmotic remediation technology utilizes an external DC electric field to drive ion migration and electroosmotic flow, exhibiting good deep desalination capabilities in low-permeability soils. However, it suffers from the following major drawbacks: ① The pH in the cathode zone rises sharply, leading to the formation of carbonates and hydroxides from Ca²⁺, Mg²⁺, etc., which clog soil pores and passivate the electrodes; ② The electroosmotic process is accompanied by the migration of a large amount of pore water to the cathode, resulting in severe soil dehydration and compaction, decreased conductivity, and rapid decline in treatment efficiency; ③ Electrode polarization is prone to occur during long-term operation.
[0005] While some existing technologies have attempted to combine electroosmosis and leaching, most are simply superpositions and fail to effectively address issues such as cathodic precipitation blockage, difficulty in completely removing salts accumulated after electroosmotic desalination, low efficiency of single leaching desalination, and salt recovery. Consequently, they struggle to achieve stable, efficient, and low-consumption in-situ remediation results. Therefore, there is an urgent need to develop an in-situ remediation device and method that deeply couples directional electroosmotic migration with leaching scouring, achieving high efficiency, low consumption, and intelligent control. Summary of the Invention
[0006] To address the problems of low efficiency and easy secondary salt deposition near electrodes in existing saline soil desalination technologies, such as electroosmosis, and high water consumption and incomplete removal of deep salts by leaching, this invention discloses an in-situ saline soil desalination device and method based on electroosmosis-leaching synergy. It constructs an integrated system with an intelligent control module as the central control core, an electroosmosis desalination module providing electroosmosis driving force, a leaching synergy module implementing targeted leaching, and a salt discharge and recovery module realizing salt solution collection. Each module works synergistically in the in-situ soil treatment area, achieving efficient, water-saving, and environmentally friendly desalination of saline soil through a collaborative operation process of "directional salt enrichment through electroosmosis → precise removal through leaching → salt solution recovery and discharge." This system is suitable for in-situ saline soil improvement needs in various scenarios such as farmland and roadbeds.
[0007] According to the first aspect, an in-situ saline soil desalination device based on electroosmosis-leaching synergy includes an intelligent control module (1), an electroosmosis desalination module (2), a leaching synergy module (3), a salt discharge and recovery module (4), an in-situ soil treatment zone (5), and a soil sensing module (6). The intelligent control module (1) is electrically / communicationally connected to the electroosmotic desalination module (2), the leaching coordination module (3), and the soil sensing module (6), respectively. The intelligent control module (1) is used to receive real-time detection data from the soil sensing module (6), dynamically adjust the electroosmotic voltage, leaching action sequence, and working mode of each module, realize the coordinated automated operation of electroosmosis and leaching, and simultaneously complete the desalination efficiency calculation, desalination standard determination, and low power consumption maintenance control. The electroosmotic desalination module (2) is electrically connected to the intelligent control module (1). The electroosmotic desalination module (2) constructs a DC electric field through symmetrically arranged anodes and cathodes, driving salt ions in the in-situ soil treatment area (5) to migrate directionally to the vicinity of the cathode for enrichment, providing a targeted enrichment basis for subsequent leaching. The electroosmotic desalination module (2) includes an electroosmotic electrode and an anti-corrosion conductive coating. The anodes and cathodes of the electroosmotic electrode are symmetrically arranged on both sides of the in-situ soil treatment area (5), and the surface is coated with an anti-corrosion conductive coating. They are arranged in an equally spaced multi-electrode array pattern to cover the target desalination area and avoid incomplete local desalination. The leaching synergy module (3) is electrically connected to the intelligent control module (1). The leaching synergy module (3) is used to receive the trigger command from the intelligent control module (1) and precisely spray the leaching liquid onto the cathode salt enrichment area to achieve efficient salt leaching. At the same time, the precise targeted spraying design avoids ineffective leaching and saves water resources. The leaching synergy module (3) only includes a targeted spraying system. The targeted spraying system is equipped with a leaching flow rate control component. The nozzle is nested and fixed on the outside of the leaching support. The spraying depth can be adjusted according to the soil layer thickness to accurately cover the salt enrichment core area. The leaching flow rate control component is electrically connected to the intelligent control module (1) to achieve automated and precise control of the leaching flow rate. The salt discharge and recovery module (4) is used to collect the salt solution formed by the salt carried by the leaching liquid, and after filtration, it is discharged to the designated area in compliance with the standards to avoid the salt solution polluting the surrounding environment. The salt discharge and recovery module (4) includes a porous liquid collection pipe, a filter geotextile, a salt solution temporary storage tank and a salt solution flow detection component. The salt solution flow detection component is used to detect the amount of salt solution recovered per unit time in real time, and to provide data support for the desalination compliance judgment. The in-situ soil treatment zone (5) is the core area for in-situ desalination of saline soil. The electroosmotic electrodes of the electroosmotic desalination module (2), the nozzles of the leaching synergy module (3), the porous liquid collection pipes of the salt discharge and recovery module (4), and the sensors of the soil sensing module (6) are all arranged in this area, in layers of surface (0-20cm), middle layer (20-60cm), and deep layer (60-150cm), to meet the desalination needs of saline soil at different depths. The soil sensing module (6) is communicatively connected to the intelligent control module (1). The soil sensing module (6) includes a layered salinity sensor, which is deployed in the in-situ soil treatment area (5) and near the cathode in a "layered + fixed-point" mode. The sensor surface is coated with an anti-corrosion coating to adapt to the high-salt and humid corrosive conditions of saline soil. It is used to detect the initial salinity concentration C0 and the salinity concentration C during the desalination process of each soil layer in the in-situ soil treatment area (5) in real time. t and the salt concentration C near the cathode t The detection data is transmitted to the intelligent control module (1) in real time, replacing manual sampling and detection, and improving detection accuracy and control efficiency. Furthermore, the intelligent control module (1) includes an intelligent regulation device and a regulation terminal, wherein the regulation terminal can automatically calculate a preset threshold C of salt concentration near the cathode. f Desalination efficiency ε and salt solution recovery threshold V f The intelligent control device automatically switches between the working modes of electroosmosis and leaching based on sensor data to achieve time-series coordination without the need for manual input of soil parameters. The targeted spraying system of the leaching coordination module (3) adopts a retractable multi-stage nozzle design. The nozzle and leaching support are quick-release snap-fit nested structures, which can accurately adjust the spraying depth and coverage. The nozzle adopts a fan-shaped atomizing spraying structure to increase the contact area between the leaching liquid and soil particles and improve the salt dissolution efficiency. Furthermore, the porous liquid collection pipe of the salt recovery module (4) is made of corrosion-resistant material, with uniform pores inside, and is horizontally arranged at the bottom of the in-situ soil treatment area (5) and corresponding to the cathode area. The filter geotextile is wrapped around the outer surface of the porous liquid collection pipe to intercept soil particles and allow the salt solution to pass through, thus avoiding pipe blockage. The salt solution flow detection component is a rotor flow meter or a volumetric metering tank, which is made of corrosion-resistant material and is suitable for salt solution corrosion conditions. Furthermore, the soil sensing module (6) uses a corrosion-resistant electrochemical salt sensor with a detection accuracy of ≤±10mg / kg and a response time of ≤30s. The connection line with the intelligent control module (1) uses a corrosion-resistant shielded wire to avoid signal interference. The detection data transmission frequency is once every 10~30 minutes and can be adjusted as needed by the control terminal.
[0008] According to the second aspect, an in-situ saline soil desalination method based on electroosmosis-leaching synergy, relying on the in-situ saline soil desalination device based on electroosmosis-leaching synergy described in any one of the first aspects, includes the following steps: S1. Start the desalination device and power the intelligent control module (1), electroosmotic desalination module (2), leaching synergy module (3), and soil sensing module (6) through the power supply inside the chassis. The soil sensing module (6) starts automatically and detects the initial salt concentration C0 of the surface, middle and deep layers of the in-situ soil treatment area (5) in real time. The detected data is transmitted to the control terminal of the intelligent control module (1). The control terminal automatically calculates the salt concentration threshold C near the cathode for each soil layer. f Simultaneously, adjust the salt solution flow detection component to normal operating condition; S2. The intelligent control module (1) sends a start command to the electroosmotic desalination module (2) based on the C0 data transmitted by the soil sensing module (6). The electroosmotic electrode constructs a DC electric field with the electric field strength E controlled at 0.5~2.5V / m, driving the salt ions in the in-situ soil treatment area (5) to be directionally enriched towards the cathode. S3. Soil sensing module (6) detects salt concentration C near the cathode in real time. t The data is transmitted to the intelligent control module (1) in real time. When the control terminal determines C t ≥C f At that time, the leaching synergy module (3) is automatically triggered to start targeted spraying, spraying the leaching solution onto the salt-rich area. The leaching flow rate Q is matched with the electroosmotic voltage U to ensure efficient elution of salt; among which, k f The value is the electroosmotic salt enrichment coefficient (ranging from 1.5 to 3.0). The control terminal can automatically fine-tune k based on the soil clay content. f ; S4. The leachate carries the enriched salts to form a salt solution, which is collected through a porous collection pipe and a filter geotextile. The amount of salt solution recovered per unit time, V, is detected by a salt solution flow detection device. t After simple filtration, the subsequent salt solution is directly discharged into the designated area in compliance with standards to avoid environmental pollution. S5. The soil sensing module (6) detects the salt concentration of each soil layer in the in-situ soil treatment area (5) in real time. The intelligent control module (1) automatically calculates the desalination efficiency ε based on the detection data. During the rinsing process, an "intermittent spraying" mode is adopted to avoid excessive rinsing that could damage the soil structure. When V t ≤V for 2 consecutive hours f When ε≥80%, the desalination standard is met by double judgment. The intelligent control module (1) reduces the electroosmotic voltage and the rinsing flow rate. The control device enters the low power consumption maintenance mode to maintain the soil salinity and complete the desalination operation. Furthermore, in step S3, after the electroosmotic enrichment stage is initiated, the soil sensing module (6) continuously monitors C. t Changes occur without human intervention; in step S5, the desalination efficiency ε is calculated using the following formula: Salt solution recovery threshold V f The calculation formula is: Total daily spraying duration T for intermittent spraying 总 The calculation formula is: Compared with the prior art, the present invention has the following advantages: 1. The electroosmosis-leaching synergistic desalination mode is adopted. The salt ions are targeted to the cathode through electroosmosis and then washed away by targeted spraying. This solves the problems of difficult removal of salt after salt accumulation, soil compaction, low efficiency of single leaching desalination, and serious waste of water resources. It significantly improves the desalination efficiency and desalination effect of saline soil. 2. Add a soil sensing module to realize real-time automated detection of salt concentration, replace manual sampling and detection, avoid human operation errors, and at the same time, work with the intelligent control module to realize fully automated regulation and control without frequent manual intervention, reduce labor costs, and improve regulation accuracy and stability. 3. The leaching synergy module adopts a precise targeted spraying design, which can dynamically adjust the spraying depth and flow rate according to the soil salinity distribution, accurately act on the cathode salt-rich area, avoid ineffective leaching, and effectively save water resources; the salt discharge and recovery module adopts a layered liquid collection and filtration anti-clogging design, which improves the salt solution collection efficiency, avoids pipeline blockage, and performs simple filtration treatment on the salt solution to ensure that it meets the discharge standards, taking into account both environmental protection and practicality. 4. Each module adopts a layered layout to adapt to the desalination needs of saline soil at different depths. The nozzles are retractable and quick-release designed. The sensors and flow detection components are all designed to be corrosion resistant to adapt to outdoor corrosion conditions of saline soil, thus improving the adaptability, durability and practicality of the device. 5. By using multiple formulas to quantify and control parameters (electric field strength, rinsing flow rate, threshold, desalination efficiency, etc.), combined with dual compliance judgment logic, the desalination effect is ensured to be stable, with a desalination efficiency of ≥80%, which can be widely applied to various in-situ saline soil desalination treatment scenarios. Attached Figure Description
[0009] To more clearly illustrate the technical solutions and advantages in the embodiments of the present invention or 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 only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0010] Figure 1 This is a schematic diagram illustrating the system framework and working principle of the in-situ saline soil desalination device based on electroosmosis-leaching synergy of the present invention. Figure 2 This is a schematic diagram of the on-site installation of the electroosmosis-leaching synergistic desalination device provided in an embodiment of the present invention; Figure 3 This is a schematic diagram of the intelligent control module structure; Figure 4 This is a schematic diagram of the electroosmotic desalination and leaching synergistic module structure; Figure 5 This is a schematic diagram of the salt discharge and recovery module. Figure 6 This is a schematic diagram of the structure of the in-situ soil treatment area; Figure 7 This is a schematic diagram of the soil sensing module.
[0011] In the diagram: 1-Intelligent control module, 101-Intelligent regulation device, 102-Intelligent regulation terminal, 103-Power management unit, 2-Electroosmosis desalination and leaching synergistic module, 201-Electroosmosis electrode, 2011-Electroosmosis anode, 2012-Electroosmosis cathode, 202-Anti-corrosion conductive coating, 203-Leaching support, 204-Targeted spraying system, 2041-Retractable multi-stage nozzle, 2042-Flexible pressure-resistant delivery pipe, 205-Leaching... 3-Salt discharge and recovery module; 301-Porous liquid collection pipe; 302-Filter geotextile; 303-Salt solution temporary storage tank; 304-Salt solution flow detection component; 4-In-situ soil treatment zone; 401-Surface layer (0-20cm), 402-Middle layer (20-60cm), 403-Deep layer (60-150cm); 5-Soil sensing module; 501-Layered salt sensor; 502-Corrosion-resistant shielded wire. Detailed Implementation
[0012] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.
[0013] like Figure 1 As shown in the figure, this invention provides a system framework diagram of an in-situ saline soil desalination device based on electroosmosis-leaching synergy, including an intelligent control module 1, an electroosmosis desalination module 2, a leaching synergy module 3, a salt discharge and recovery module 4, an in-situ soil treatment zone 5, and a soil sensing module 6. The intelligent control module (1) is electrically connected to the electroosmotic desalination module (2) and the leaching coordination module (3), and is communicatively connected to the salt solution flow detection component (304) of the soil sensing module (6) and the salt discharge recovery module (4). It is the central control core of the device, receiving various detection data and completing parameter calculation, mode switching, command output and desalination standard determination. The electroosmotic desalination module (2) constructs a layered and adapted DC electric field in the in-situ soil treatment zone (5) to drive salt ions to migrate directionally to the vicinity of the cathode for enrichment; The leaching coordination module (3) receives the trigger command from the intelligent control module (1) and performs layered targeted atomization leaching on the cathode salt enrichment area to dissolve and enrich the salt. The salt recovery module (4) is installed at the bottom of the in-situ soil treatment area (5) to collect the salt solution formed by leaching and to achieve filtration, temporary storage and discharge in compliance with standards. The soil sensing module (6) is deployed in the in-situ soil treatment area (5) in a “layered + fixed point” mode to detect salt concentration data in real time and transmit it to the intelligent control module (1); The in-situ soil treatment area (5) is the core area for in-situ desalination of saline soil. It is divided into surface layer (0-20cm), middle layer (20-60cm), and deep layer (60-150cm) according to depth. Each functional module is arranged in layers to meet the desalination needs of saline soil at different depths.
[0014] In this embodiment, as Figure 2 The diagram shows a three-dimensional schematic of an in-situ saline soil desalination device based on electroosmosis-leaching synergy. The electroosmosis-leaching synergy desalination device consists of an intelligent control module 1, an electroosmosis desalination module 2, a leaching synergy module 3, a salt discharge and recovery module 4, an in-situ soil treatment zone 5, and a soil sensing module 6.
[0015] In this embodiment, as Figure 3The diagram shows the structure of the intelligent control module 1. The intelligent control module (1) includes an intelligent control device (101), an intelligent control terminal (102), and a power management unit (103). The whole is an integrated chassis made of anti-corrosion and flame-retardant material. It is located in the operating area next to the in-situ soil treatment area (5) and is suitable for the outdoor high-salt and humid corrosion conditions of saline soil. Its core functions are receiving detection data, automatically calculating control parameters, coordinating control of electroosmosis / leaching timing, switching of working modes, and dual judgment of desalination compliance. The intelligent control device (101) is equipped with an industrial-grade PLC programmable logic controller, a multi-channel signal acquisition card, a DC voltage regulation module, a flow control module, and a power management unit. The multi-channel signal acquisition card is connected to the soil sensing module (6) and the salt solution flow detection component (304) through a corrosion-resistant shielded wire to achieve accurate reception and filtering amplification of salt concentration signal and salt solution flow signal. The signal acquisition accuracy is ≤ ±0.1mV and the operation response time is ≤1s. The DC voltage regulation module can output an adjustable DC voltage of 0~100V to provide an appropriate electroosmotic voltage for the electroosmotic desalination module (2). The flow control module can accurately adjust the leaching flow rate with a control accuracy of ≤ ±0.1L / h. The power management unit converts the external 220V mains power to 12V / 24V DC power to power the intelligent control module (1) itself and components such as the soil sensing module (6) and the leaching synergy module (3). It also integrates overcurrent, overvoltage, and short circuit protection functions to prevent circuit abnormalities from damaging the equipment. The control terminal (102) is equipped with a touch LCD screen and physical function buttons. The LCD screen can display in real time the initial salt concentration C0 of each soil layer in the in-situ soil treatment area (5) and the salt concentration C near the cathode. t Actual recovery volume of salt solution V t Key parameters include desalination efficiency ε, electroosmotic voltage U, and leaching flow rate Q, as well as operating modes such as electroosmotic enrichment, targeted leaching, and low-power maintenance; physical function buttons allow manual setting of the electroosmotic salt enrichment coefficient k. f Soil stratification adaptation coefficient K, desalination efficiency threshold ε f The control terminal (102) has a built-in dedicated control algorithm that can automatically calculate the preset threshold C of salt concentration near the cathode based on the C0 data transmitted by the soil sensor module (6). This allows for the control of parameters such as device start-up and shutdown, manual / automatic mode switching, and data export. f Salt solution recovery threshold V f It automatically matches the layer adaptation coefficient K based on the soil layer location and calculates the optimal DC electric field strength E, realizing fully automated control without frequent manual intervention.
[0016] In this embodiment, as Figure 4The diagram shows the structure of the electroosmotic desalination and leaching synergistic module. The electroosmotic desalination module (2) is the power unit for electroosmotic desalination, including an electroosmotic electrode (201), an anti-corrosion conductive coating (202), and a leaching support (203). A DC electric field is constructed in the in-situ soil treatment area (5) by symmetrically arranged anodes (2011) and cathodes (2012), driving salt ions to migrate directionally to the vicinity of the cathode (2012) to form a salt enrichment area, providing a basis for subsequent targeted leaching. The electroosmotic electrode (201) is a metal alloy electrode, which is symmetrically arranged on the left and right sides of the in-situ soil treatment area (5) in a multi-electrode array pattern with equal spacing. The horizontal distance L between the anode (2011) and the cathode (2012) is set to 1~5m according to the scale of the desalination area. The depth of the electrode inserted into the soil is flush with the deep layer (60-150cm) of the in-situ soil treatment area (5) to ensure that the electric field covers the entire soil layer. The surfaces of the anode (2011) and the cathode (2012) are coated with a polytetrafluoroethylene anti-corrosion conductive coating (202), which significantly improves the corrosion resistance of the electrode in saline soil and extends the service life of the equipment. The leaching support (203) is an L-shaped metal support, fixed on the outside of the anode (2012), serving as the mounting base for the leaching synergy module (3) targeted spraying system (204). Its placement corresponds to the salt enrichment core area 5-10cm outside the cathode (2012), ensuring that the spraying range of the nozzle accurately covers the salt enrichment area. The DC electric field strength E constructed by the electroosmotic desalination module (2) is calculated according to the formula. The calculation is as follows: U is the electroosmotic voltage controlled by the intelligent control module (1), L is the horizontal distance between the anode (2011) and the cathode (2012), and K is the soil stratification adaptation coefficient. The coefficient is automatically adjusted according to the soil depth of the in-situ soil treatment area (5): surface layer (0-20cm), K=0.8~1.0, middle layer (20-60cm), K=1.0~1.2, deep layer (60-150cm), K=1.2~1.4. The electric field strength E is controlled at 0.5~2.5V / m, which ensures the efficiency of salt ion directional migration and avoids the damage to the soil structure caused by excessive electric field. At the same time, it adapts to the resistivity difference and electric field attenuation characteristics of different soil depths to achieve precise desalination in layers. The leaching synergy module (3) is the core unit of salt elution, including a targeted spraying system (204) and a leaching flow control component (205), which is electrically connected to the intelligent control module (1) to realize layered targeted atomized leaching of the cathode salt enrichment area. The leaching flow is precisely controlled by the leaching flow control component (205) to avoid ineffective leaching, save water resources, and prevent soil compaction caused by excessive leaching. The targeted spraying system (204) includes a telescopic multi-stage nozzle (2041) and a flexible pressure-resistant delivery pipe (2042). The telescopic multi-stage nozzle (2041) is fixed on the leaching support (203) by a quick-release buckle. Each cathode (2012) corresponds to one nozzle. The nozzle can extend and retract along the axial direction, with an extension and retraction adjustment range of 0~1.5m. The spraying depth can be precisely adjusted according to the layer thickness of the surface, middle and deep layers of the in-situ soil treatment area (5) to ensure that the leaching liquid directly acts on the cathode salt enrichment area of the corresponding soil layer. The nozzle has a fan-shaped atomization structure with a water outlet diameter of 0.5~1mm, an atomized droplet diameter of 50~200μm, and a spraying radius of 0.05~0.1m, which can increase the contact area between the leaching liquid and soil particles and improve the salt dissolution efficiency. The flexible pressure-resistant conveying pipe (2042) is connected to the telescopic multi-stage nozzle (2041). The pipe body has a built-in sealing ring and can extend and retract synchronously with the nozzle, without leakage of the washing liquid. Its material is a flexible polymer material that is resistant to salt corrosion and is suitable for outdoor saline soil conditions. The rinsing flow control component (205) adopts a small cylindrical anti-corrosion and sealing structure with a diameter of 3-5cm and a length of 8-12cm. The outer shell is made of an integrated smooth anti-corrosion material, which is suitable for outdoor corrosion conditions of saline soil. It is integrated and installed on the flexible pressure-resistant conveying pipe (2042) near the connection node between the telescopic multi-stage nozzle (2041) and the external rinsing liquid supply device. Each nozzle corresponds to one rinsing flow control component (205), which can extend and retract synchronously with the nozzle to ensure the stability of flow control. This component is electrically connected to the flow control module of the intelligent control module (1) and can receive the instructions of the intelligent control module (1) to realize the automatic and precise control of rinsing flow. The rinsing flow adjustment range is 0.5~5L / h, which can be dynamically adapted according to the electroosmotic voltage and soil salinity concentration. The leaching synergy module (3) adopts an intermittent spraying mode, which is triggered by the intelligent control module (1) to start and stop. Each spraying lasts for 30 minutes with an interval of 1 hour, avoiding excessive leaching that could damage the soil structure. At the same time, it achieves time-series synergy with electroosmotic enrichment, ensuring salt leaching efficiency. The leaching flow rate is precisely executed by the leaching flow rate control component (205) according to the instructions of the intelligent control module (1).
[0017] In this embodiment, as Figure 5 The diagram shows the structure of the salt collection and discharge system 4. The salt discharge and recovery module (4) is located at the right end of the in-situ soil treatment area (5) and is arranged perpendicular (horizontally) to the direction of the electroosmotic electrode array. It is used to efficiently collect the salt solution formed by leaching within the entire treatment area and to achieve filtration, temporary storage and discharge in compliance with standards. The salt discharge and recovery module (4) includes a porous liquid collection pipe (301), a filter geotextile (302), a salt solution temporary storage tank (303) and a salt solution flow detection component (304). The porous liquid collection pipe (301) is made of PVC anti-corrosion material and is laid horizontally in a long strip at the bottom right edge of the in-situ soil treatment area (5). Its direction is perpendicular to the arrangement direction of the electroosmotic electrodes (201) (i.e., it runs horizontally through the width of the treatment area). The pipe has uniform pores with a porosity of 15% to 25%. The pores face the center of the in-situ soil treatment area (5) to avoid backflow of soil particles from the outside and blockage of the pores. At the same time, the bottom of the in-situ soil treatment area (5) is set with a horizontal slope of 0.3% to 0.5% from left to right, sloping towards the porous liquid collection pipe (301) to ensure that the salt solution from each cathode salt enrichment area on the left side can efficiently infiltrate into the pipe under the action of gravity, and avoid the salt solution from stagnating in the soil. The filter geotextile (302) is made of polyester synthetic fiber and is tightly wrapped around the outer surface of the porous liquid collection pipe (301). It intercepts soil particles, silt and other impurities through physical interception and only allows the salt solution to pass through, further preventing the pores of the porous liquid collection pipe (301) from becoming blocked and ensuring the salt solution collection efficiency. The salt solution temporary storage tank (303) is a corrosion-resistant plastic storage tank, which is connected to the porous liquid collection pipe (301) through a pipe to realize the temporary storage and standard discharge of the salt solution: the collected salt solution is discharged to the designated area through the pipe after simple filtration treatment to avoid secondary pollution. The salt solution flow detection component (304) is a corrosion-resistant rotor flow meter, installed on the porous liquid collection pipe (301), which can detect the amount of salt solution recovered V per unit time in real time. t The flow data is transmitted to the intelligent control module (1), whose detection accuracy is adapted to the requirements of the device for desalination compliance determination, for V t With V f The comparison and judgment provide accurate data.
[0018] In this embodiment, as Figure 6 The diagram shows the structure of the in-situ soil treatment area 4. The in-situ soil treatment area (5) is the core area for in-situ desalination of saline soil. No additional excavation is required, which minimizes the damage to the original soil structure. According to the depth of the saline soil, it is divided into the surface layer (401, 0-20cm), the middle layer (402, 20-60cm), and the deep layer (403, 60-150cm). The electroosmotic electrode (201) of the electroosmotic desalination module (2), the retractable multi-stage nozzle (2041) of the leaching synergy module (3), the porous liquid collection pipe (301) of the salt discharge and recovery module (4), and the salt sensor of the soil sensing module (6) are all arranged according to the soil layer to adapt to the desalination needs of saline soil at different depths, ensuring that each soil layer can achieve the synergistic operation of electroosmotic directional enrichment and targeted leaching and elution. Under the driving force of the DC electric field of the electroosmotic desalination module (2), the salt ions in the in-situ soil treatment zone (5) migrate directionally to the salt enrichment zone near the cathode (2012) along the direction of the electric field. After the atomized leaching liquid of the leaching synergy module (3) is accurately sprayed to the salt enrichment zone, the enriched salt is dissolved to form a salt solution. Under the action of gravity, the salt solution is collected along the bottom of the treatment zone to the porous liquid collection pipe (301) at the right end, and finally enters the porous liquid collection pipe (301) of the salt discharge and recovery module (4) to complete the collection, realizing the in-situ desalination process of "salt ion enrichment-dissolution-collection-discharge".
[0019] In this embodiment, as Figure 7 The diagram shows the structure of the soil sensing module 6. The soil sensing module (6) includes a layered salt sensor (501) and a corrosion-resistant shielded wire (502). It is a real-time salt concentration detection unit. It is deployed in the in-situ soil treatment area (5) in a layered + fixed-point mode to replace the traditional manual sampling and detection, avoid operational errors, and provide accurate and real-time salt data for the regulation and desalination standard determination of the intelligent control module (1). The layered salt sensor (501) is a corrosion-resistant electrochemical salt sensor with an anti-corrosion coating on its surface. Its detection accuracy is ≤±10mg / kg, and its response time is ≤30s. It is suitable for the high-salt, moist corrosive conditions of saline soil. It consists of a surface sensor, a middle sensor, a deep sensor, and a cathode fixed-point sensor. The surface, middle, and deep sensors are respectively deployed in the middle of the corresponding soil layers in the in-situ soil treatment area (5) to detect the initial salt concentration C0 and the salt concentration C during the desalination process of each soil layer in real time. t The cathode fixed-point sensors are deployed in the salt enrichment core area 5-10 cm outside each cathode (2012), with at least one sensor deployed in each of the surface, middle, and deep layers, to monitor the salt concentration C near the cathode in real time. t It accurately reflects the salt enrichment status; The anti-corrosion shielding line (502) is the connection line between the soil sensing module (6) and the intelligent control module (1), which can effectively avoid corrosion of saline soil and interference from external signals, and ensure the stability of detection data transmission. The detection data transmission frequency of the soil sensing module (6) is 10~30 minutes / time, which can be adjusted as needed by the control terminal (102) of the intelligent control module (1), and the change in salt concentration is fed back to the intelligent control module (1) in real time, providing data support for the flow regulation of the rinsing flow control component (205).
[0020] This invention also provides an in-situ desalination method for saline soil based on electroosmosis-leaching synergy, which is implemented using the aforementioned in-situ saline soil desalination device based on electroosmosis-leaching synergy, and includes the following steps: S1 device startup and initial salt content detection: Start the desalination device, power the intelligent control module (1), electroosmotic desalination module (2), leaching synergy module (3), and soil sensing module (6) through the power supply in the chassis, debug the salt solution flow detection component (304) to normal working state, and confirm that each module is connected normally and without faults. The soil sensing module (6) automatically starts and uses surface, middle and deep sensors to detect the initial salt concentration C0 of each soil layer in the in-situ soil treatment area (5) in real time. The detected data is transmitted to the control terminal (102) of the intelligent control module (1) through the anti-corrosion shielding line (502). The control terminal (102) then uses the formula... Automatically calculates the preset threshold C of salt concentration near the cathode for each soil layer. f , where k f The value of k is the electroosmotic salt enrichment coefficient, ranging from 1.5 to 3.0, and the control terminal (102) can automatically fine-tune k according to the soil clay content. f When the clay content is ≥20%, k f =1.5~2.0, k when clay content <20% f =2.0~3.0; S2 electroosmosis initiation and salt-oriented enrichment: The control terminal (102) of the intelligent control module (1) automatically matches the corresponding soil stratification adaptation coefficient K based on the C0 data and soil layer location transmitted by the soil sensing module (6), and uses the formula... Calculate the optimal DC electric field strength E, control E within 0.5~2.5V / m, and send a start command to the electroosmotic desalination module (2); The electroosmotic electrode (201) of the electroosmotic desalination module (2) constructs a DC electric field. Under the driving force of the electric field, salt ions in the in-situ soil treatment zone (5) migrate directionally along the direction of the electric field and are eventually enriched in the salt enrichment core area 5-10 cm outside the cathode (2012). The electroosmotic enrichment stage lasts for 24-48 hours. No human intervention is required during this stage. The cathode fixed-point sensor of the soil sensing module (6) continuously monitors the salt concentration C near the cathode. t And transmit the data to the intelligent control module (1) in real time; S3 leaching triggering and targeted salt elution, the intelligent control module (1) and its control terminal (102) compare the C transmitted by the cathode fixed-point sensor in real time. t With the preset C f The value, when determining C t ≥C f When the time comes, the system automatically sends a leaching trigger command to the leaching coordination module (3) to start the targeted spraying system (204) and the leaching flow control component (205); The external rinsing solution supply device outputs rinsing solution, which is then transported to the rinsing flow rate control component (205) via a flexible pressure-resistant conveying pipe (2042). The rinsing flow rate control component (205), according to the instructions of the intelligent control module (1), adjusts the rinsing flow rate Q to a value that matches the electroosmotic voltage U. The matching formula is as follows: k is the flow rate adjustment coefficient, with a value of 0.8~1.2L / (h·V), to ensure the efficiency of salt dissolution and elution; the leaching liquid after flow rate adjustment is delivered to the retractable multi-stage nozzle (2041), and the nozzle automatically adjusts the retraction amount according to the corresponding soil layer thickness, and atomizes the leaching liquid and sprays it precisely onto the cathode salt enrichment area to dissolve the enriched salt. The rinsing process adopts an intermittent spraying mode, which is precisely controlled by the intelligent control module (1). Each spraying lasts for 30 minutes with an interval of 1 hour to avoid excessive rinsing that could damage the soil structure. The rinsing liquid carries dissolved salts to form a salt solution, which gathers at the bottom of the in-situ soil treatment area (5) under the action of gravity. S4 Salt solution collection and recycling: The salt solution collected at the bottom of the in-situ soil treatment area (5) is filtered by geotextile (302) to trap soil particles, silt and other impurities, and then seeps into the porous liquid collection pipe (301) and is collected by the salt discharge and recovery module (4). The salt solution flow detection component (304) detects the amount of salt solution recovered V per unit time in real time. t The flow data is transmitted to the intelligent control module (1); the collected salt solution enters the salt solution storage tank (303) through the pipeline, and after simple filtration, it is discharged to the designated area to avoid environmental pollution after ensuring that the salt concentration is ≤3g / L. S5 desalination compliance determination and low power consumption maintenance: The surface, middle and deep sensors of the soil sensing module (6) continuously and in real time detect the salt concentration C of each soil layer in the in-situ soil treatment area (5). t The intelligent control module (1) is based on the formula Automatically calculate the desalination efficiency ε of each soil layer; The intelligent control module (1) transmits the V signal from the salt solution flow detection component (304). t With respect to the preset salt solution recovery threshold V f Continuous comparison, among which V f According to the formula Calculations are performed, where S is the horizontal area of the in-situ soil treatment zone (5), h is the effective leaching depth, ρ is the soil bulk density (taken as 1.1~1.5 g / cm³), and ε is the soil density. f The minimum desalination efficiency threshold is set at 80%. When V t ≤V for 2 consecutive hours fWhen ε≥80%, the intelligent control module (1) makes a dual judgment that the desalination meets the standard, automatically reduces the electroosmotic voltage output to the electroosmotic desalination module (2), and reduces the leaching flow rate of the leaching synergy module (3). The control device enters the low power consumption maintenance mode, continuously monitors and maintains the stability of soil salinity, and completes the in-situ desalination operation of saline soil.
[0021] This invention solves the technical problems of existing saline soil desalination technologies, such as low deep desalination efficiency and easy secondary salt deposition near the electrodes in electroosmosis, and high water consumption and incomplete removal of deep salts in leaching, by combining deep synergistic control of electroosmosis and leaching. It has the advantages of high desalination efficiency, low water consumption, high degree of automation, good soil structure protection, and strong adaptability to working conditions. It can be widely used in desalination and remediation projects of various in-situ saline soils such as farmland, roadbed, green space and industrial sites.
[0022] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.
Claims
1. A device for the synergistic remediation of in-situ saline soil based on electroosmosis and leaching, characterized in that, It includes an intelligent control module (1), an electroosmotic desalination module (2), a leaching synergy module (3), a salt discharge and recovery module (4), an in-situ soil treatment zone (5), and a soil sensing module (6). The intelligent control module (1) is electrically connected to the electroosmotic desalination module (2) and the leaching coordination module (3) respectively, and is used to dynamically adjust the electroosmotic voltage and the leaching action sequence to realize the coordinated operation of electroosmosis and leaching. The electroosmotic desalination module (2) is an electroosmotic driving unit. It constructs a DC electric field through symmetrically arranged anodes and cathodes to drive salt ions in the in-situ soil treatment area (5) to migrate directionally to the vicinity of the cathode for enrichment. The electroosmotic desalination module (2) includes electroosmotic electrodes and anti-corrosion conductive coating. The anodes and cathodes of the electroosmotic electrodes are symmetrically arranged on both sides of the in-situ soil treatment area (5), and the surface is coated with an anti-corrosion conductive coating. They are arranged in an equally spaced multi-electrode array pattern to cover the target area. The DC electric field intensity E constructed by the electroosmotic electrode satisfies the following formula: Where E is the DC electric field strength (V / m), U is the electroosmotic voltage (V) controlled by the intelligent control module (1), K is the layer adaptation coefficient (surface 0-20cm, K=0.8~1.0, middle layer 20-60cm, K=1.0~1.2, deep layer 60-150cm, K=1.2~1.4), which is automatically matched by the intelligent control module (1) according to the differences in soil layers; C0 is the average value of the initial salt concentration of each soil layer (mg / kg), which is obtained by taking the arithmetic mean of the detection data of n salt sensors deployed in the corresponding soil layer by the soil sensing module (6); n is the number of salt sensors deployed in a single soil layer (n≥3) to ensure the representativeness of the detection data; L is the distance between the anode and the cathode (m). The leaching synergistic module (3) includes a spraying system; the nozzle of the targeted spraying system is nested and fixed on the outside of the leaching support to accurately cover the salt enrichment area; it is used to spray leaching solution onto the cathode salt enrichment area; The salt recovery module (4) collects the salt solution in the in-situ soil treatment area (5) through a porous liquid collection pipe and a filter geotextile. After simple filtration, it is directly discharged to the designated compliant treatment area. The soil sensing module (6) includes a layered salinity sensor, arranged in layers of "surface (0-20cm) + middle layer (20-60cm) + deep layer (60-150cm)". Each soil layer has at least 3 sensors (n≥3), and an additional salinity sensor is placed near each cathode. All sensor surfaces are coated with an anti-corrosion coating to adapt to saline soil corrosion conditions. It is used to detect the initial salinity concentration C0 of each soil layer (the detection value of n sensors in a single soil layer) and the salinity concentration C near the cathode in real time. t The detection data is transmitted to the intelligent control module (1) in real time, and the intelligent control module (1) automatically calculates the data. .
2. The in-situ saline soil desalination device based on electroosmosis-leaching synergy according to claim 1, characterized in that, The intelligent control module (1) includes an intelligent control device and a control terminal. The intelligent control logic is as follows: The control terminal automatically calculates based on the detection data of n sensors in each soil layer transmitted by the soil sensing module (6). and the preset threshold C of salt concentration near the cathode f Real-time comparison of C t With C f The numerical relationship between the electroosmotic voltage output value and the rinsing flow rate is used to dynamically adjust the electroosmotic voltage output value and the rinsing flow rate. The intelligent control device automatically switches between electroosmotic enrichment mode, leaching and elution mode, and low power consumption maintenance mode based on the salt concentration data of the soil sensing module (6) and the salt solution flow data of the salt discharge and recovery module (4).
3. The in-situ saline soil desalination device based on electroosmosis-leaching synergy according to claim 1, characterized in that, The targeted spraying system of the leaching synergy module (3) adopts a retractable multi-stage nozzle design, and the nozzle and leaching support are quick-release snap-fit nested structures. The nozzle body adopts an axial telescopic structure, which can be adjusted according to the layer thickness of the in-situ soil treatment zone (5) and... The spray depth is automatically adjusted to ensure that the rinsing solution directly acts on the cathodic salt enrichment zone of the corresponding soil layer; The nozzle and the leaching support are nested and fixed by quick-release buckles. Each cathode corresponds to 1-2 nozzles. The spray range of the nozzle accurately covers the salt enrichment core area around the cathode. The nozzle adopts a fan-shaped atomizing spray structure to atomize the rinsing liquid into droplets, increasing the contact area with soil particles; The nozzle and the leaching support of the leaching co-working module (3) are connected by a flexible pressure-resistant delivery pipe. The flexible pressure-resistant delivery pipe extends and retracts synchronously with the nozzle, and has a built-in sealing ring to ensure that there is no leakage of leaching liquid during the extension and retraction of the nozzle.
4. The in-situ saline soil desalination device based on electroosmosis-leaching synergy according to claim 1, characterized in that, The salt drainage and recovery module (4) includes a porous liquid collection pipe, a filter geotextile, a salt solution temporary storage tank, and a salt solution flow detection component; The porous liquid collection pipe is horizontally arranged at the bottom right end of the in-situ soil treatment area (5), and its direction is perpendicular to the electroosmotic electrode array. The pipe is made of corrosion-resistant material and has uniform pores inside, which is used to collect salt solution. The filter geotextile, made of polyester synthetic fiber, is wrapped around the outer surface of the porous liquid collection pipe and is used to trap soil particles while allowing salt solutions to pass through. The brine storage tank is connected to a porous collection pipe for temporarily storing the collected brine solution, which is then discharged after simple filtration. The salt solution flow detection component is arranged in a porous collection pipe, which collects salt solution recovery data in real time and transmits it to the intelligent control module (1). The parameters such as E work together to provide data support for intelligent control and the determination of desalination compliance.
5. The in-situ saline soil desalination device based on electroosmosis-leaching synergy according to claim 1, characterized in that, The salinity sensors of the soil sensing module (6) are deployed in a "layered + fixed-point" pattern: The salinity sensor is divided into surface, middle and deep sensors, which are respectively deployed in the middle of the corresponding soil layer in the in-situ soil treatment area (5). The sensor near the cathode is deployed 5-10cm outside the cathode (the core area of salinity enrichment). At least one sensor is deployed in each soil layer and near each cathode to ensure the comprehensiveness and accuracy of the detection data. The sensor transmits the detection data to the intelligent control module (1) in real time. The transmission frequency is once every 10-30 minutes and can be adjusted as needed by the control terminal.
6. The in-situ saline soil desalination device based on electroosmosis-leaching synergy according to claim 1, characterized in that, The electroosmotic desalination module (2) uses titanium-plated ruthenium alloy or stainless steel alloy as its electroosmotic electrode. The anti-corrosion conductive coating is a polytetrafluoroethylene coating with a thickness of 0.1-0.3 mm. The length of the electroosmotic electrode is 150-200 cm, the diameter is 2-5 cm, and the spacing of the electrode array is 0.5-1.5 m. The intelligent control module (1) can adjust the output value of the electroosmotic voltage U according to the difference in salt concentration of each soil layer transmitted by the soil sensing module (6).
7. The in-situ saline soil desalination device based on electroosmosis-leaching synergy according to claim 1, characterized in that, The targeted spraying system of the leaching synergy module (3) is equipped with a leaching flow rate control component. This component is electrically connected to the intelligent control module (1) and can realize precise automatic control of the leaching flow rate. Its leaching flow rate adjustment range is set to 0.5-5L / h, which can adapt to the needs of different soil salt enrichment levels and electroosmosis operation intensity. The rinsing flow rate is automatically matched by the intelligent control module (1) according to the electroosmotic voltage value according to a preset ratio.
8. An in-situ desalination method for saline soil based on electroosmosis-leaching synergy, characterized in that, The synergistic control logic of the method includes: after the electroosmotic enrichment stage lasts for 24-48 hours, the leaching function is triggered; during leaching, an "intermittent spraying" mode is adopted, with each spraying lasting 30 minutes and an interval of 1 hour, in order to avoid excessive leaching that could damage the soil structure; when the amount of salt solution recovered is below the threshold for 2 consecutive hours, it is determined that the desalination standard has been met and the method enters a low-power maintenance mode.
9. A method for in-situ desalination of saline soil based on electroosmosis-leaching synergy, characterized in that, In the method, a preset threshold is set for the salt concentration near the cathode. , where k f The value of k is the electroosmotic salt enrichment coefficient, ranging from 1.5 to 3.0, and the control terminal can automatically fine-tune k based on the soil clay content. f When the clay content is ≥20%, k f =1.5-2.0, k when clay content <20% f =2.0-3.0; the recycling rate of the rinsing solution is ≥60%, and the salt concentration must meet the standard requirement of ≤3g / L before the salt solution is discharged.
10. A method for in-situ desalination of saline soil based on electroosmosis-leaching synergy, according to the apparatus of any one of claims 1-7 and the method of any one of claims 8-9, characterized in that, Includes the following steps: S1. Start the desalination device and supply power to the intelligent control module (1), electroosmotic desalination module (2), leaching synergy module (3), and soil sensing module (6) through an external power supply; S2. The intelligent control module (1) sends a start command to the electroosmotic desalination module (2) based on the C0 data transmitted by the soil sensing module (6). The electroosmotic electrode constructs a DC electric field to drive the salt ions in the in-situ soil treatment area (5) to be directionally enriched towards the cathode. S3. Soil sensing module (6) detects salt concentration C near the cathode in real time. t The data on salt concentration in each soil layer are transmitted to the intelligent control module (1), which automatically calculates the salt concentration data. When the control terminal determines C t ≥C f When the target spraying is activated, the leaching synergy module (3) is automatically triggered to spray the leaching solution onto the salt-rich area; S4. The leachate carries the enriched salts to form a salt solution, which is collected through a porous collection pipe and a filter geotextile. The amount of salt solution recovered per unit time, V, is detected by a salt solution flow detection device. f The salt solution is then filtered briefly before being discharged into a designated area in compliance with standards. S5. Intelligent Control Module (1) According to , According to the formula Automatically calculate the desalination efficiency ε. When ε≥80% and the salt solution recovery amount is below the threshold for 2 consecutive hours, the desalination is deemed to be up to standard. The intelligent control module (1) automatically reduces the electroosmotic voltage U and reduces the rinsing flow rate, switches to the low power consumption maintenance mode, continuously monitors and maintains the stability of soil salinity, and completes the desalination operation.