Rapid treatment device and method for neonicotinoid pesticide polluted water in river network area

Abstract

The invention discloses a rapid treatment device and method for neonicotinoid pesticide polluted water in a river network area, and belongs to the technical field of water treatment. The device comprises a mixing unit, a settling separation unit and an adsorption medium circulating unit, the mixing unit is provided with a tangential water inlet and an adsorption medium feeding port; the settling separation unit is used for realizing rapid gravity separation of the adsorbed medium and water; and the adsorption medium circulation unit is used for medium recovery and regeneration. The invention also discloses a special core-shell structure composite particle adsorption medium and a preparation method thereof, and a rapid adsorption treatment method based on the device. Through the physical process of eddy enhanced mixing-rapid settling separation, the problems that a traditional adsorption technology is low in treatment speed, prone to blockage and low in flux are solved, and the device and the method are particularly suitable for emergency treatment of sudden and large-flow trace neonicotinoid pesticide polluted water in river network areas and have the advantages of being rapid in response, large in treatment flux, reliable in operation and low in cost.

Description

Technical Field

[0001] This invention belongs to the field of water treatment technology, specifically relating to a rapid treatment device and method for neonicotinoid pesticide-contaminated water in river network areas, and particularly to a mobile rapid purification device that utilizes the principles of eddy current rapid adsorption and gravity sedimentation to treat neonicotinoid pesticide-contaminated water in river network areas. Background Technology

[0002] Neonicotinic pesticide pollution in river networks is characterized by low concentrations, sudden onset, and rapid spread, requiring emergency response technologies that combine rapid response, high-throughput treatment, and high reliability. However, current mainstream technologies all have significant shortcomings and are unable to meet this comprehensive requirement.

[0003] First, while direct addition of powdered activated carbon is simple to operate, the material is difficult to recover, easily causing secondary pollution, and its removal depth and efficiency for trace pollutants are limited. Second, although granular activated carbon fixed-bed adsorption devices can avoid material loss, their adsorption rate is limited by the slow diffusion of pollutants into the pores inside the carbon particles, resulting in excessively long reaction times. More importantly, as a deep filter, this method is easily clogged by suspended solids in the high-turbidity water of river networks, causing a sharp drop in treatment throughput or even operational interruption, making it unsuitable for high-flow-rate treatment. Finally, although advanced oxidation technologies such as ozone oxidation have rapid reactions, the oxidant is ineffectively consumed by a large amount of background substances in the water, resulting in high costs for treating trace dispersed pollutants and the risk of generating unknown byproducts.

[0004] Existing improvement schemes mostly focus on enhancing the adsorption or catalytic performance of the materials themselves, but have failed to overcome the fundamental engineering bottleneck of balancing "treatment speed, throughput, and anti-clogging" from the perspective of process principles, thus restricting their practical application in river network emergency scenarios. Therefore, there is an urgent need to develop a new method and device that can simultaneously achieve rapid contact, efficient solid-liquid separation, and adapt to large-flow, high-turbidity water bodies. Summary of the Invention

[0005] To address the aforementioned problems, this invention provides a rapid treatment device and method for neonicotinoid pesticide-contaminated water in river network areas. This device utilizes the principles of eddy current rapid adsorption and gravity sedimentation to treat neonicotinoid pesticide-contaminated water in river network areas.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A rapid treatment device for neonicotinoid pesticide-contaminated water in river network areas includes a mixing unit, a sedimentation separation unit, and an adsorption medium circulation unit connected in sequence by pipelines. The adsorption medium circulation unit includes a collection tank and a regeneration tank, which are connected to the mixing unit. Wastewater is pumped in through a tangential inlet on the mixing unit, and clean water is discharged from the sedimentation separation unit.

[0007] As described above, the mixing unit is provided with an adsorption medium inlet, the ratio of its height to diameter being 1.5:1 to 3:1, and the sedimentation separation unit is connected to the bottom of the mixing unit, the cross-sectional area of ​​which is 2 to 4 times that of the mixing unit.

[0008] As described above, the mixing unit is a vertical cylindrical structure or a frustum structure; the sedimentation separation unit is an inverted conical structure with a cone angle of 55°-65°.

[0009] The device as described above further includes an inlet unit and an outlet unit. The inlet unit includes a water pump and a pipeline for conveying polluted water to the tangential inlet of the mixing unit at a flow rate of 0.5-2.0 m / s. The outlet unit is located on the upper part of the side wall of the sedimentation separation unit.

[0010] As described above, the collection tank is connected to the sedimentation separation unit to receive saturated adsorption medium from the sedimentation separation unit; the regeneration tank contains a regenerant for eluting and regenerating the saturated adsorption medium; the regeneration tank is equipped with a stirring device; and the regenerated adsorption medium is sent back to the mixing unit by a transfer pump.

[0011] In the device described above, the adsorption medium used for the rapid processing device is a composite particulate adsorption medium with an apparent density greater than 1.2 g / cm³ and less than 2.5 g / cm³.

[0012] In the device described above, the composite particle adsorption medium has a core-shell structure, with its core being quartz sand, ceramsite, or activated alumina particles with a particle size of 0.2-1.0 mm, and its outer shell being an adsorption active layer loaded with a zirconium-based porphyrin coordination polymer, wherein the loading amount of the zirconium-based porphyrin coordination polymer is 1%-10% of the mass of the core particles.

[0013] Another object of the present invention is to provide a method for preparing the composite particle adsorption medium of the device, comprising the following steps: S1. The core of porous inert heavy particles with a particle size of 0.2-1.0 mm is subjected to acid washing, water washing and high-temperature calcination activation treatment at 500-600℃. S2. Prepare an active loading solution containing zirconium salt at a concentration of 0.05-0.2 mol / L and porphyrin derivative at a concentration of 0.01-0.05 mol / L, using a mixture of water and ethanol in a volume ratio of 1:1 to 1:3. S3. Immerse the core particles treated in step S1 into the solution prepared in step S2 at a solid-liquid ratio of 1:5~1:10 g / mL, and stir the reaction at 60-80℃ so that the active substances are loaded onto the particle surface through coordination to form an adsorption active layer. S4. Dry the loaded particles to obtain the composite particle adsorption medium.

[0014] In the preparation method of the composite particle adsorption medium as described above, the reaction is stirred for 4-8 hours in step S3.

[0015] The method for preparing the composite particle adsorption medium as described above involves drying the loaded particles at 80-105°C for 4-12 hours.

[0016] Another object of the present invention is to provide a method for treating neonicotinoid pesticide-contaminated water using the aforementioned apparatus, comprising the following steps: R1. Add composite particle adsorption medium into the mixing unit and control its volume concentration in the mixing unit to be 1%-3%; R2. The neonicotinoid pesticide contaminated water to be treated is pumped into the mixing unit through the tangential inlet at a flow rate of 0.8-1.5 m / s, so that it mixes and contacts with the adsorption medium. R3. The mixed mud-water mixture enters the sedimentation and separation unit, where the adsorption medium settles rapidly under gravity, and the supernatant after separation is discharged as treated effluent. R4. Periodically discharge saturated adsorption medium, accounting for about 5%-20% of the total medium volume, from the bottom of the sedimentation separation unit and transport it to the adsorption medium circulation unit for regeneration. The regenerated medium is then reused in step R1.

[0017] In the method for treating neonicotinoid pesticide-contaminated water as described above, in step R2, the cross-sectional flow velocity of the contaminated water in the mixing unit is controlled to be 0.01-0.05 m / s.

[0018] The regeneration method in step R4 of the above-described method for treating neonicotinoid pesticide-contaminated water is as follows: using an ethanol solution with a volume concentration of 60%-65%, the saturated adsorption medium is shaken or stirred and soaked at 40-50°C for elution, or soaked and eluted at room temperature using a sodium hydroxide-sodium carbonate buffer solution with a pH of 9-10.

[0019] As described above, the method for treating neonicotinoid pesticide-contaminated water involves elution in an ethanol solution for 1-2 hours or soaking and elution in a sodium hydroxide-sodium carbonate buffer solution for 2-4 hours during regeneration.

[0020] In the method for treating neonicotinoid pesticide-contaminated water as described above, the stirring speed in the regeneration tank is 50-200 rpm.

[0021] Due to the adoption of the above technical solution, the beneficial effects of the present invention are as follows: This application resolves the contradiction between adsorption and sedimentation, and between capacity and recovery through the synergistic design of a heavy core and a specific adsorption shell; The device in this application adopts a unique eddy current-sedimentation integrated structure, which breaks through the bottleneck of slow adsorption speed and easy clogging of traditional fixed bed, and realizes rapid and high-throughput processing. This invention provides a complete emergency purification solution, from specialized materials and core devices to optimized processes. The method is simple, the medium is recyclable, and the operating cost is low. It is particularly suitable for the rapid and high-throughput treatment of sudden neonicotinoid pesticide contamination in river network areas. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the rapid treatment device for neonicotinoid pesticide-contaminated water in river network areas in Embodiment 3 of this application; Figure 2 This is a schematic diagram of the treatment principle of the rapid treatment device for neonicotinoid pesticide-contaminated water in river network areas, as described in this application. The system consists of: 1. Mixing unit; 2. Sedimentation and separation unit; 3. Collection tank; and 4. Regeneration tank. Detailed Implementation

[0023] To enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below. The specific embodiments listed below are merely descriptions of the principles and features of the present invention, and the examples are only for explaining the present invention and are not intended to limit the scope of the present invention. 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.

[0024] Example 1: Preparation of composite particle adsorption medium Take 200 grams of quartz sand with a particle size of 0.4-0.6 mm and place it in a 1-liter beaker. Add 500 ml of 1 mol / L dilute hydrochloric acid and stir at room temperature for 2 hours to remove surface impurities. Wash the quartz sand repeatedly with deionized water until neutral, then transfer it to a muffle furnace and calcine at 550°C for 3 hours for high-temperature activation. After cooling, it is ready for use.

[0025] Preparation of active loading solution: Weigh 6.44 g of zirconium nitrate hexahydrate and 0.72 g of tetracarboxyphenylporphyrin, dissolve them in 800 mL of solvent made by mixing deionized water and anhydrous ethanol in a volume ratio of 1:2, and stir until completely dissolved.

[0026] All activated quartz sand was immersed in the above-mentioned loading solution and placed in a constant temperature water bath at 75°C for continuous stirring and reaction for 6 hours. After the reaction was completed, the solid particles were separated by filtration, washed successively with deionized water and ethanol, and finally dried in an oven at 100°C for 8 hours to obtain the composite particle adsorption medium loaded with zirconium-based porphyrin coordination polymer, labeled Zr-TCPP@QS. The active component loading was calculated to be approximately 4.5% of the quartz sand mass, and the apparent density of the composite particles was approximately 1.8 g / cm³.

[0027] Example 2 Preparation of composite particle adsorption medium Take 200 grams of ceramsite with a particle size of 0.4-0.6 mm and place it in a 1-liter beaker. Add 500 ml of 1 mol / L dilute hydrochloric acid and stir at room temperature for 2 hours to remove surface impurities. Wash the ceramsite repeatedly with deionized water until neutral, then transfer it to a muffle furnace and calcine at 550℃ for 3 hours for high-temperature activation. After cooling, it is ready for use.

[0028] Preparation of active loading solution: Weigh 6.44 g of zirconium nitrate hexahydrate and 0.72 g of tetracarboxyphenylporphyrin, dissolve them in 800 mL of solvent made by mixing deionized water and anhydrous ethanol in a volume ratio of 1:2, and stir until completely dissolved.

[0029] All activated ceramsite particles were immersed in the above-mentioned loading solution and placed in a constant temperature water bath at 75℃ for continuous stirring and reaction for 6 hours. After the reaction was completed, the solid particles were separated by filtration, washed successively with deionized water and ethanol, and finally dried in an oven at 100℃ for 8 hours to obtain the composite particle adsorption medium loaded with zirconium-based porphyrin coordination polymer, labeled Zr-TCPP@CA. The active component loading was calculated to be approximately 3.5%-4.5% of the ceramsite mass, and the apparent density of the composite particles was approximately 1.7 g / cm³.

[0030] Example 3: Rapid processing device and its usage method A rapid treatment device for neonicotinoid pesticide-contaminated water in river network areas, such as... Figure 1 , 2 As shown, it includes a mixing unit 1, a sedimentation separation unit 2 and an adsorption medium circulation unit connected in sequence by pipelines. The adsorption medium circulation unit includes a collection tank 3 and a regeneration tank 4. The regeneration tank 4 is connected to the mixing unit 1. Wastewater is pumped in through a tangential inlet on the mixing unit, and clean water is discharged through the sedimentation separation unit 2.

[0031] The device also includes an inlet unit and an outlet unit. The inlet unit includes a water pump and a pipeline for conveying polluted water to the tangential inlet of the mixing unit 1 at a flow rate of 0.5-2.0 m / s. The outlet unit is located on the upper part of the side wall of the sedimentation separation unit 2.

[0032] The mixing unit is cylindrical or a frustum structure with a smaller top and larger bottom, with a height-to-diameter ratio of 1.5:1 to 3:1. It is used to create a vortex inside the water to be treated and to force mixing and contact between the water and the adsorption medium. The upper part of the mixing unit 1 is provided with an adsorption medium inlet. The sedimentation separation unit 2 is connected to the bottom of the mixing unit 1 and its cross-sectional area is 2-4 times that of the mixing unit 1. The sedimentation separation unit 2 is used to realize the gravity sedimentation separation of the adsorption medium that has adsorbed pollutants from the water, and the hydraulic residence time is 1-3 minutes.

[0033] The adsorption medium circulation unit is used to collect, regenerate saturated adsorption medium and return it to the mixing unit.

[0034] In a preferred embodiment, the mixing unit 1 is a vertical cylindrical structure; the sedimentation separation unit 2 is an inverted conical structure with a cone angle of 55°-65°. Wastewater enters the mixing unit 1 through a tangential swirling flow in the middle. An overflow weir or outlet is provided at the top of the sedimentation separation unit, and the outlet is connected to the mixing unit 1 via a pipe. When overflow occurs in the sedimentation separation unit, the wastewater is pumped back to the mixing unit 1.

[0035] The collection tank 3 is connected to the sedimentation separation unit 2 and is used to receive the saturated adsorption medium from the sedimentation separation unit; the regeneration tank 4 is equipped with a regenerator for eluting and regenerating the saturated adsorption medium; the regeneration tank 4 is equipped with a stirring device; and the regenerated adsorption medium is sent back to the mixing unit 1 by a transfer pump.

[0036] A method for treating neonicotinoid pesticide-contaminated water using the aforementioned device includes the following steps: R1. Add composite particle adsorption medium into mixing unit 1, and control its volume concentration in the mixing unit to be 1%-3%; R2. The neonicotinoid pesticide contaminated water to be treated is pumped into the mixing unit through the tangential inlet at a flow rate of 0.8-1.5 m / s, so that it mixes and contacts with the adsorption medium; the cross-sectional flow velocity of the contaminated water in the mixing unit is 0.01-0.05 m / s; R3. The mixed mud-water mixture enters the sedimentation separation unit 2. The adsorption medium settles rapidly under the action of gravity, and the supernatant after separation is discharged as treated effluent. R4. Periodically discharge saturated adsorption medium, accounting for about 5%-20% of the total medium volume, from the bottom of sedimentation separation unit 2 and transport it to the adsorption medium circulation unit for regeneration. The regenerated medium is reused in step R1.

[0037] The specific method for regenerating the adsorption medium is as follows: use an ethanol solution with a volume concentration of 60%-65% to shake or stir and soak the saturated adsorption medium at 40-50℃, or soak and elute it at room temperature with a sodium hydroxide-sodium carbonate buffer solution with a pH of 9-10.

[0038] Example 4: Verification of the rapid adsorption treatment performance of the device A small experimental apparatus was constructed according to the structure described in Example 3. The mixing unit was a cylindrical acrylic glass tube with a diameter of 10 cm and a height of 20 cm, with a height-to-diameter ratio of 2:1. The sedimentation and separation unit was an inverted conical acrylic glass tube with a cone angle of 60 degrees.

[0039] The Zr-TCPP@QS adsorbent obtained in the preparation example and Zr-TCPP@CA were respectively added to the mixing unit, and their volume concentration in the mixing zone was controlled to be 2%. Imidacloprid was prepared with an initial concentration of 5 mg / L to simulate wastewater. The peristaltic pump was started to pump the wastewater into the tangential inlet of the mixing unit at a flow rate of 1.2 m / s. Stable vortex flow was observed to form in the mixing unit, in which the adsorbent was uniformly suspended.

[0040] After the system was started, continuous sampling and testing were performed at the upper outlet of the sedimentation unit. High-performance liquid chromatography (HPLC) analysis showed that the concentration of imidacloprid in the effluent stabilized below 0.08 mg / L only 2 minutes after the device was started, with a removal rate exceeding 98%. After the water inlet was stopped, the adsorption medium was observed to settle rapidly within the sedimentation separation unit, completing solid-liquid separation within approximately 80 seconds. This embodiment verifies that the device and method of the present invention can achieve deep purification in a very short time. Both Zr-TCPP@QS and Zr-TCPP@CA media achieved a stable removal rate of over 98% for imidacloprid, demonstrating comparable adsorption performance. The main differences between the two are: Zr-TCPP@CA, due to the porous structure of the ceramic particle core, has a more uniform loading of active components, and the effluent concentration remains stable between 0.075-0.085 mg / L within 2 hours of continuous operation, exhibiting superior adsorption stability; Zr-TCPP@QS, due to the smooth surface of the quartz sand, has a slightly faster settling speed (completing solid-liquid separation in approximately 75 seconds), resulting in slightly higher solid-liquid separation efficiency. Both media are suitable for this device, and the appropriate medium can be selected based on water quality characteristics and cost requirements in practical applications.

[0041] Example 5: Exploration of Optimization of Key Process Parameters Using the above-mentioned device and medium, with a fixed influent pollutant concentration of 5 mg / L imidacloprid and a medium volume concentration of 2%, the effects of mixing contact time and influent tangential flow velocity on the treatment effect were systematically investigated.

[0042] Tests showed that when the influent tangential flow velocity was controlled within the range of 0.8 to 1.5 m / s, and the mixing contact time was maintained at 1 to 3 minutes, the concentration of the treated effluent could be consistently below the target value of 0.1 mg / L with a removal rate of >98%. If the flow velocity was too low, such as 0.5 m / s, or the contact time was too short, such as less than 1 minute, the removal efficiency would drop to 87% or lower.

[0043] If the influent tangential velocity is too high (e.g., greater than 1.5 m / s), although the mixing intensity is further enhanced, it will have two negative effects: First, the strong shear force may cause some of the active layer on the surface of the adsorption medium to detach, affecting the service life of the medium; second, the excessively high upward flow velocity will disrupt the stable flow state within the sedimentation separation unit, causing some fine adsorption medium particles to be carried out of the system by the water flow (i.e., the "material run-out" phenomenon), resulting in medium loss and increased turbidity of the effluent. Experiments show that when the flow velocity reaches 2.0 m / s, a small amount of suspended medium particles can be detected in the effluent, and the removal rate actually decreases to about 92%. Therefore, controlling the tangential flow velocity within the range of 0.8-1.5 m / s can ensure both efficient adsorption and stable system operation and effective media retention.

[0044] Example 6: Regeneration and Recycling Performance of the Adsorption Medium The Zr-TCPP@QS medium saturated with adsorption from Example 4 was removed, and a 65% (v / v) ethanol solution was used as the regenerator. The medium was eluted by shaking at 50°C for 2 hours. The eluted medium was then washed with deionized water and dried to obtain the regenerated medium.

[0045] Comparative tests revealed that after one regeneration, the saturated adsorption capacity of the medium for imidacloprid could be restored to over 95% of that of the fresh medium. When the regenerated medium was reintroduced into a small-scale test apparatus for dynamic adsorption experiments, the time required to reach the same effluent standard was only about 8% longer than that of the fresh medium. Further experiments involving five consecutive "adsorption-elution-regeneration" cycles showed that even after the fifth cycle, the dynamic adsorption performance of the medium, measured by the time to reach standard effluent, still maintained over 70% of its initial performance. This demonstrates that the regeneration method employed in this invention is highly efficient and feasible, and that the medium possesses good reusability.

[0046] Comparative Example: A Comprehensive Comparison with Traditional Fixed-Bed Adsorption Technology A control experiment was set up: conventional granular activated carbon (GAC) with the same treatment scale and a 20-40 mesh fixed bed adsorption column were used. The simulated wastewater treated in parallel with the device of this invention was supplemented with 200 mg / L of kaolin to simulate high turbidity river network water.

[0047] The comparison results are as follows: Processing speed: The device of this invention achieves effluent quality within 2 minutes; while the GAC fixed bed requires about 30 minutes of empty bed contact time, that is, 30 minutes of operation, to make the effluent approach the same standard.

[0048] Anti-clogging and flux maintenance capabilities: During a 2-hour continuous test, the influent and effluent flow rates of the device of this invention remained stable. In contrast, the GAC fixed bed, after about 40 minutes of operation, experienced a flow rate decrease of more than 35% under constant influent pressure due to kaolin particles clogging the bed, demonstrating significant clogging problems.

[0049] The adsorption medium in this application is suitable for treating wastewater with a pH value of 5.0-9.0. For water bodies with extreme pH values ​​outside this range (such as strongly acidic industrial wastewater or strongly alkaline agricultural drainage), the pH should be adjusted to the neutral range before treatment to ensure the best adsorption effect and long-term stability of the medium.

[0050] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A rapid treatment device for neonicotinoid pesticide-contaminated water in river network areas, characterized in that: It includes a mixing unit (1), a sedimentation separation unit (2) and an adsorption medium circulation unit connected in sequence by pipelines. The adsorption medium circulation unit includes a collection tank (3) and a regeneration tank (4). The regeneration tank (4) is connected to the mixing unit (1). Wastewater is pumped in through a tangential inlet on the mixing unit, and clean water is discharged from the sedimentation separation unit (2).

2. The rapid treatment device for neonicotinoid pesticide-contaminated water in river network areas according to claim 1, characterized in that: The mixing unit (1) is provided with an adsorption medium inlet, the ratio of its height to its diameter is 1.5:1 to 3:1, the sedimentation separation unit (2) is connected to the bottom of the mixing unit (1), and its cross-sectional area is 2 to 4 times that of the mixing unit (1).

3. A rapid treatment device for neonicotinoid pesticide-contaminated water in river network areas according to claim 2, characterized in that: The mixing unit (1) is a vertical cylindrical structure or a frustum structure; the sedimentation separation unit (2) is an inverted conical structure with a cone angle of 55°-65°.

4. A rapid treatment device for neonicotinoid pesticide-contaminated water in river network areas according to claim 1, characterized in that: The device also includes an inlet unit and an outlet unit. The inlet unit includes a water pump and a pipeline for conveying polluted water to the tangential inlet of the mixing unit (1) at a flow rate of 0.5-2.0 m / s. The outlet unit is located on the upper side wall of the sedimentation separation unit (2).

5. A rapid treatment device for neonicotinoid pesticide-contaminated water in river network areas according to claim 1, characterized in that: The collection tank (3) is connected to the sedimentation separation unit (2) and is used to receive the saturated adsorption medium from the sedimentation separation unit; the regeneration tank (4) is provided with a regenerating agent for eluting and regenerating the saturated adsorption medium, and the regeneration tank (4) is provided with a stirring device. The regenerated adsorption medium is sent back to the mixing unit (1) by a transfer pump.

6. A rapid treatment device for neonicotinoid pesticide-contaminated water in river network areas according to claim 1, characterized in that: The adsorption medium used in the rapid processing device is a composite particulate adsorption medium with an apparent density greater than 1.2 g / cm³ and less than 2.5 g / cm³.

7. A method for preparing a composite particulate adsorption medium for use in the apparatus according to any one of claims 1-6, characterized in that, Includes the following steps: S1. The core of porous inert heavy particles with a particle size of 0.2-1.0 mm is subjected to acid washing, water washing and high-temperature calcination activation treatment at 500-600℃. S2. Prepare an active loading solution containing zirconium salt at a concentration of 0.05-0.2 mol / L and porphyrin derivative at a concentration of 0.01-0.05 mol / L, using a mixture of water and ethanol in a volume ratio of 1:1 to 1:

3. S3. Immerse the core particles treated in step S1 into the solution prepared in step S2 at a solid-liquid ratio of 1:5~1:10 g / mL, and stir the reaction at 60-80℃ so that the active substances are loaded onto the particle surface through coordination to form an adsorption active layer. S4. Dry the loaded particles to obtain the composite particle adsorption medium.

8. The method for preparing a composite particle adsorption medium according to claim 7, characterized in that: The porous inert heavy particle core includes quartz sand, ceramsite, or activated alumina particles with a particle size of 0.2-1.0 mm. The outer shell is an adsorption active layer loaded with a zirconium-based porphyrin coordination polymer, wherein the loading amount of the zirconium-based porphyrin coordination polymer is 1%-10% of the mass of the core particles. The composite particle adsorption medium has a core-shell structure.

9. A method for treating neonicotinoid pesticide-contaminated water using the apparatus according to any one of claims 1-7, characterized in that, Includes the following steps: R1. Add composite particle adsorption medium into the mixing unit (1) and control its volume concentration in the mixing unit to be 1%-3%; R2. The neonicotinoid pesticide contaminated water to be treated is pumped into the mixing unit through the tangential inlet at a flow rate of 0.8-1.5 m / s, so that it mixes and contacts with the adsorption medium. R3. The mixed mud-water mixture enters the sedimentation separation unit (2). The adsorption medium settles rapidly under gravity, and the supernatant after separation is discharged as treated effluent. R4. Periodically discharge saturated adsorption medium accounting for about 5%-20% of the total medium volume from the bottom of the sedimentation separation unit (2) and transport it to the adsorption medium circulation unit for regeneration. The regenerated medium is then reused in step R1.

10. The method according to claim 9, characterized in that: In step R2, the cross-sectional flow velocity of the polluted water in the mixing unit is 0.01-0.05 m / s. The specific regeneration method in step R4 is as follows: using an ethanol solution with a volume concentration of 60%-65%, the saturated adsorption medium is shaken or stirred and soaked and eluted at 40-50℃, or soaked and eluted at room temperature using a sodium hydroxide-sodium carbonate buffer solution with a pH of 9-10.

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