A nuclear crystallization-advanced oxidation coupling process for synergistically removing high-concentration fluoride ions and refractory organic matter in wastewater

Abstract

A nucleus crystal granulation-advanced oxidation coupling process for the synergistic removal of high-concentration fluoride ions and refractory organic matter in wastewater. Based on the occurrence form and ion crystallization characteristics of fluoride ions in water, combined with the catalytic activation characteristics of oxidants, the crystal-inducing carrier, precipitant and oxidant are selected and added. By regulating the water chemical conditions and hydraulic parameters, the crystal-inducing carrier is suspended in the inner cylinder of the nucleus crystal granulation device, thereby inducing the fluoride ions in the water to crystallize and precipitate on its surface; at the same time, the active sites on the surface of the hydroxylated crystal-inducing carrier catalyze and activate the oxidant to efficiently produce active free radicals, thereby completing the synergistic degradation / mineralization of refractory organic matter in the water. This process utilizes the synergistic effect between nucleus crystal granulation and catalytic oxidation to achieve the removal of refractory organic matter in wastewater and the resource recovery of fluoride ions, greatly improving the wastewater treatment efficiency while reducing the wastewater treatment cost.

Description

Technical Field

[0001] The present invention belongs to the technical field of water purification, and in particular relates to a nucleation granulation-advanced oxidation coupling process for collaboratively removing high-concentration fluoride ions and refractory organic matter in wastewater. Background Art

[0002] Various industries, such as the coking, phosphate fertilizer, and pharmaceutical industries, release waste containing various hazardous substances into the environment. For example, calcium magnesium phosphate fertilizer undergoes defluorination when temperatures reach above 1000°C, releasing fluorine as silicon tetrafluoride. Some of this fluoride is also released during water quenching. Levofloxacin, a fluoroquinolone antibacterial drug, has various synthesis methods and can be produced directly by chemical synthesis using tetrafluorobenzoic acid as a starting material. These industries generate large amounts of wastewater high in fluoride and organic matter during industrial production. The indiscriminate discharge of this wastewater can lead to endemic fluorosis, cause significant damage to the ecological environment, and affect crop yield and quality.

[0003] Currently, the commonly used methods for treating fluoride-containing and organic wastewater include coagulation and sedimentation, chemical precipitation, adsorption, ion exchange, electrocoagulation, and reverse osmosis. As for reverse osmosis, ion exchange, and electrodialysis, although they have high removal rates for fluoride ions and organic matter in water bodies, the treatment costs are high, and therefore they cannot be widely used. Adsorption is widely used due to its low operating and management requirements and simple and easy operation, but it also has problems such as long adsorption time, high operating costs, and safety. As for chemical precipitation, this method is simple and easy to use, but its fluoride removal efficiency is limited by the solubility of calcium fluoride and it cannot synergistically remove organic matter coexisting in the water body. At the same time, the high water content sludge it produces also greatly increases the subsequent treatment costs.

[0004] Therefore, in view of the coexistence of high-concentration fluoride ions and organic matter in wastewater, and considering the need for resource recovery and utilization of fluoride ions, it is urgent to develop a new process that is efficient, low-consumption, and short-process to synergistically remove organic matter and recover fluoride ions. Summary of the Invention

[0005] The purpose of the present invention is to overcome the shortcomings of the existing technology and provide a nuclear crystallization granulation-advanced oxidation coupling process for the synergistic removal of high-concentration fluoride ions and refractory organic matter in wastewater, so as to achieve resource recovery and utilization of fluoride ions in the wastewater while efficiently degrading the refractory organic matter in the wastewater, thereby improving the wastewater treatment efficiency and reducing its treatment cost.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is:

[0007] A coupled process of nucleation granulation and advanced oxidation for synergistically removing high-concentration fluoride ions and refractory organic matter in wastewater, characterized by comprising:

[0008] Adding a crystal-inducing carrier, a precipitant and an oxidant to the wastewater; the precipitant is calcium chloride;

[0009] Regulating water chemical conditions and hydraulic parameters so that the crystal-inducing carrier is suspended in the inner cylinder of the nucleus crystal granulation device, thereby inducing fluoride ions in the water to crystallize and precipitate on its surface;

[0010] The nuclear crystal granulation device comprises an outer cylinder and an inner cylinder. The inner cylinder is suspended in the outer cylinder and is connected from top to bottom. The outlets of the water inlet pipe and the dosing pipe are both located below the inner cylinder. A toothed overflow weir and a water outlet pipe are provided on the top of the outer cylinder, and a crystal inducing carrier discharge pipe is provided at the bottom.

[0011] Raw water enters the inner cylinder through the water inlet pipe, and the precipitant and oxidant enter the inner cylinder through the dosing pipe. During the reaction, high-concentration fluoride ions and calcium ions generate calcium fluoride crystals attached to the surface of the seed crystals under the action of chemical bonding. At the same time, the adsorption sites on the surface of the crystal-inducing carrier adsorb the difficult-to-degrade organic matter, and under the action of the catalytic sites on its surface, the oxidant is catalytically activated to generate highly active free radicals, which catalytically degrade the adsorbed organic matter. As the reaction proceeds, the crystals grow to form large particles that settle at the bottom of the nucleus crystal granulation device and are discharged through the crystal-inducing carrier discharge pipe. The treated water is discharged from the water outlet pipe through the toothed overflow weir.

[0012] In one embodiment, the dosage of the crystal-inducing carrier is 0.6-2.2 g / L, the dosage of the precipitant is 90-160 mg / L, and the dosage of the oxidant is controlled at 1-6 mmol / L.

[0013] In one embodiment, the crystal-inducing carrier is garnet, calcite or fluorite, and the oxidant is one or more of hydrogen peroxide, persulfate or peroxydisulfate.

[0014] In one embodiment, the particle size of the garnet, calcite and fluorite is 180-250 μm; the garnet, calcite and fluorite need to be washed with ultrapure water and dried in an oven before use, and their surfaces are activated after drying.

[0015] In one embodiment, the regulating water chemical conditions and hydraulic parameters includes:

[0016] Control the water flow rate in the reaction system to 15-22 L / h and the pH to 6-8;

[0017] The dosing flow rate is 2-2.5L / h, and the reagents are precipitants and oxidants;

[0018] By regulating the water inlet and dosing flow rates between the fluidization velocity and the carry-out velocity, it is ensured that the velocity of the fluid passing through the crystal-inducing carrier bed is not lower than the minimum velocity causing the bed to expand, that is, the difference between the actual flow velocity of the fluid in the bed and the sedimentation velocity of the crystal-inducing carrier in the vertical direction caused by gravity is greater than 0, thereby allowing the crystal-inducing carrier to be suspended in the inner cylinder of the nuclear crystal granulation device.

[0019] In one embodiment, a water distributor is arranged directly below the inner cylinder.

[0020] In one embodiment, the precipitant and the oxidant are prepared in a dosing cartridge, and the preparation concentration is comprehensively considered based on the dosing concentration and the flow rate of the peristaltic pump: when the dosing concentration increases and the flow rate of the peristaltic pump remains unchanged, the preparation concentration of the agent should be appropriately increased; when the dosing concentration decreases and the flow rate of the peristaltic pump remains unchanged, the preparation concentration of the agent should be appropriately decreased; when the dosing concentration remains unchanged and the flow rate of the peristaltic pump increases, the preparation concentration of the agent should be appropriately decreased; when the dosing concentration remains unchanged and the flow rate of the peristaltic pump decreases, the preparation concentration of the agent should be appropriately increased; when the dosing concentration remains unchanged and the flow rate of the peristaltic pump decreases, the preparation concentration of the agent should be appropriately increased; When the concentration remains unchanged and the flow rate of the peristaltic pump increases, the concentration of the drug configuration should be appropriately lowered; when the drug concentration remains unchanged and the flow rate of the peristaltic pump decreases, the concentration of the drug configuration should be appropriately increased; when the drug concentration increases and the flow rate of the peristaltic pump increases, the concentration of the drug configuration should be maintained unchanged; when the drug concentration increases and the flow rate of the peristaltic pump decreases, the concentration of the drug configuration should be appropriately increased; when the drug concentration decreases and the flow rate of the peristaltic pump increases, the concentration of the drug configuration should be appropriately lowered; when the drug concentration decreases and the flow rate of the peristaltic pump decreases, the concentration of the drug configuration should be maintained unchanged.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] 1. The present invention integrates nucleation granulation with an advanced oxidation process, solving the problem of the existing process being unable to efficiently and synergistically remove high-concentration fluoride ions and organic matter in complex water bodies. It has important practical application value in the field of wastewater treatment, especially in the treatment of complex polluted water bodies.

[0023] 2. Experiments have shown that the process of the present invention has a good effect in treating high-concentration fluoride ions and organic matter in wastewater. The method of the present invention realizes the resource recovery and utilization of fluoride ions in wastewater. In addition, it can also be applied to water bodies containing high-valent ions and organic matter, and has a wide range of applications.

[0024] 3. The present invention is simple to operate, low in cost, high in processing efficiency, has no secondary pollution and is easy to implement on a large scale. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a schematic diagram of the structure of the core crystal granulation device.

[0026] Figure 2It is the synergistic removal effect of fluoride ions and organic matter in wastewater.

[0027] In the figure, 1-water inlet pipe; 2-water distributor; 3-dosing pipe; 4-inner cylinder; 5-outer cylinder; 6-water outlet pipe; 7-toothed overflow weir; 8-crystal-inducing carrier discharge pipe. DETAILED DESCRIPTION

[0028] The embodiments of the present invention are described in detail below with reference to the accompanying drawings and examples.

[0029] The present invention provides a coupled process of nucleation granulation and advanced oxidation for the synergistic removal of high-concentration fluoride ions and refractory organic matter in wastewater. The process is based on a nucleation granulation device. The structure of the device is as follows: Figure 1 As shown, the outer cylinder 5 and inner cylinder 4 are arranged in the outer cylinder 5, and the two are preferably coaxially arranged. In a specific configuration, the inner cylinder 4 is suspended, with both the bottom and top being open structures, extending vertically. The outer wall of the inner cylinder 4 is connected to the inner wall of the outer cylinder 5 by a bracket or other structure to achieve the installation of the inner cylinder 4. The water inlet pipe 1 and the dosing pipe 3 are connected to the outer cylinder 5, and the outlets of the water inlet pipe 1 and the dosing pipe 3 are preferably located below the inner cylinder 4. A toothed overflow weir 7 and a water outlet pipe 6 are provided at the top of the outer cylinder 5, and a crystal-inducing carrier discharge pipe 8 is provided at the bottom.

[0030] According to this structure, the optimal crystallization-inducing carrier, precipitant, and oxidant are selected and added based on the occurrence form and crystallization characteristics of fluoride ions in the water, combined with the catalytic activation properties of the oxidant. By controlling the water chemistry and hydraulic parameters, the crystallization-inducing carrier is suspended in the inner cylinder 4 of the nucleation granulation device, thereby inducing the crystallization and precipitation of fluoride ions in the water on its surface. The precipitate and supernatant are then discharged, and the supernatant is the treated water.

[0031] In the present invention, the crystallization support also acts as a catalyst. It should have a high specific surface area, high specific gravity, high impact load resistance, and a particle size that is not too large. Therefore, garnet, calcite, and fluorite are preferred. More preferably, their particle size is 180-250μm. Garnet, calcite, and fluorite must be cleaned with ultrapure water before use and then dried in an oven. After drying, they should be soaked in ultrapure water for 12-24 hours to activate their surface. This activation improves the surface reactivity of the crystallization support and promotes the adsorption and precipitation of target pollutant ions in the water.

[0032] In the present invention, based on the crystal structure of the crystal-inducing carrier, a precipitant is selected that can form a crystal structure with the target pollutant ions that is the same as or similar to that of the crystal-inducing carrier, and thus calcium chloride is preferred.

[0033] In the present invention, the oxidant is not particularly limited, but is preferably one or more of hydrogen peroxide, persulfate, or peroxydisulfate.

[0034] According to the above structure, the detailed process of the present invention is:

[0035] Raw water enters the inner drum 4 through the water inlet pipe 1, while the precipitant and oxidant enter the inner drum 4 through the dosing pipe 3. During the reaction, highly concentrated fluoride ions and calcium ions (from the precipitant) chemically bond to form calcium fluoride crystals that adhere to the surface of the seed crystals. Simultaneously, adsorption sites on the surface of the crystallization carrier adsorb refractory organic matter. The catalytic sites on its surface catalyze and activate the oxidant to produce highly active free radicals, which catalytically degrade the adsorbed organic matter, thereby achieving the synergistic degradation / mineralization of refractory organic matter in the water. As the reaction proceeds, the crystals gradually grow, and the resulting large particles settle to the bottom of the nucleation granulation device and are discharged through the crystallization carrier discharge pipe 8. The treated water is discharged from the outlet pipe 6 through the toothed overflow weir 7.

[0036] In one embodiment of the present invention, the dosage of the crystal-inducing carrier is 0.6-2.2 g / L, the dosage of the precipitant is 90-160 mg / L, and the dosage of the oxidant is controlled at 1-6 mmol / L.

[0037] In one embodiment of the present invention, regulating water chemical conditions and hydraulic parameters includes:

[0038] Control the water flow rate in the reaction system to 15-22 L / h and the pH to 6-8;

[0039] The dosing flow rate is 2-2.5L / h, and the reagents are precipitants and oxidants;

[0040] By regulating the water inlet and dosing flow rates between the fluidization velocity and the carry-out velocity, it is ensured that the velocity of the fluid passing through the crystal-inducing carrier bed is not lower than the minimum velocity causing the bed to expand, that is, the difference between the actual flow velocity of the fluid in the bed and the sedimentation velocity of the crystal-inducing carrier in the vertical direction caused by gravity is greater than 0, thereby allowing the crystal-inducing carrier to be suspended in the inner cylinder of the nuclear crystal granulation device.

[0041] In this embodiment, under the synchronous regulation of hydraulic parameters and hydrochemical conditions, the charge form of the surface of the crystallization carrier and the thickness of the compressed double layer are optimized, which effectively improves the crystallization precipitation rate of fluoride ions on its surface and the catalytic activation efficiency for oxidants, reduces the self-annihilation caused by long-distance migration of free radicals, and improves the utilization rate of active free radicals generated by the catalytic activation of the crystallization carrier.

[0042] In one embodiment of the present invention, a water distributor 2 is arranged directly below the inner cylinder 4 so that the incoming water and reagents can evenly enter the inner cylinder and pass through the crystal inducing carrier.

[0043] In one embodiment of the present invention, the precipitant and the oxidant are prepared in a dosing cartridge, and the preparation concentration is comprehensively considered based on the dosing concentration and the flow rate of the peristaltic pump: when the dosing concentration increases and the flow rate of the peristaltic pump remains unchanged, the preparation concentration of the agent should be appropriately increased; when the dosing concentration decreases and the flow rate of the peristaltic pump remains unchanged, the preparation concentration of the agent should be appropriately decreased; when the dosing concentration remains unchanged and the flow rate of the peristaltic pump increases, the preparation concentration of the agent should be appropriately decreased; when the dosing concentration remains unchanged and the flow rate of the peristaltic pump decreases, the preparation concentration of the agent should be appropriately increased; when the dosing concentration remains unchanged and the flow rate of the peristaltic pump decreases, the preparation concentration of the agent should be appropriately increased; When the drug concentration remains unchanged and the flow rate of the peristaltic pump increases, the drug configuration concentration should be appropriately lowered; when the drug concentration remains unchanged and the flow rate of the peristaltic pump decreases, the drug configuration concentration should be appropriately increased; when the drug concentration increases and the flow rate of the peristaltic pump increases, the drug configuration concentration should be maintained unchanged; when the drug concentration increases and the flow rate of the peristaltic pump decreases, the drug configuration concentration should be appropriately increased; when the drug concentration decreases and the flow rate of the peristaltic pump increases, the drug configuration concentration should be appropriately lowered; when the drug concentration decreases and the flow rate of the peristaltic pump decreases, the drug configuration concentration should be maintained unchanged.

[0044] The following are several specific embodiments of the present invention and corresponding experimental data. Based on these experimental data, the treatment effect of the present invention on high-concentration fluoride ions and refractory organic matter is confirmed.

[0045] Example 1

[0046] The water sample was wastewater from a fertilizer and feed factory. The nuclear crystallization-advanced oxidation coupling process was used to synergistically remove high-concentration fluoride ions and organic matter in the wastewater. The concentration of fluoride ions in the wastewater was 100 mg / L, and the organic matter was tetracycline with a concentration of 20 mg / L.

[0047] The treatment of the above-mentioned wastewater includes the following steps: filling garnet into the inner cylinder 4 of the nuclear crystal granulation device, the filling amount of garnet is 0.6 g / L, adjusting the water inlet pump flow to 15 L / h, the dosing pump flow to 2 L / h, and adjusting the pH of the inlet water to 6; using a peristaltic pump to introduce water through the water inlet pipe 1 and the dosing pipe 3 and adding chemicals, so that the garnet is in a fluidized state in the inner cylinder 4, wherein the amount of precipitant added to the reaction system is 120 mg / L, and the amount of oxidant added is 3 mmol / L; finally, the wastewater after the reaction overflows through the toothed overflow weir 7 and flows out of the reaction system from the outlet 6.

[0048] refer to Figure 2 After the above process treatment, the concentration of fluoride ions in the effluent was 11.3 mg / L, and the removal rate was 88.7%; the concentration of tetracycline was 3.6 mg / L, and the removal rate was 82%.

[0049] Example 2

[0050] The water sample was wastewater from a fertilizer and feed factory. The nuclear crystallization-advanced oxidation coupling process was used to synergistically remove high-concentration fluoride ions and organic matter in the wastewater. The concentration of fluoride ions in the wastewater was 100 mg / L, and the organic matter was tetracycline with a concentration of 20 mg / L.

[0051] The treatment of the above-mentioned wastewater includes the following steps: filling fluorite into the inner cylinder 4 of the nuclear crystal granulation device, the filling amount of fluorite is 1.2 g / L, adjusting the water inlet pump flow to 18 L / h, the dosing pump flow to 2.2 L / h, and adjusting the pH of the inlet water to 7; using a peristaltic pump to introduce water through the water inlet pipe 1 and the dosing pipe 3 and adding chemicals, so that the garnet is in a fluidized state in the inner cylinder 4, wherein the amount of precipitant added to the reaction system is 90 mg / L, and the amount of oxidant added is 1 mmol / L; finally, the wastewater after the reaction overflows through the toothed overflow weir 7 and flows out of the reaction system from the outlet 6.

[0052] refer to Figure 2 After the above process treatment, the concentration of fluoride ions in the effluent was 10.4 mg / L, and the removal rate was 89.6%; the concentration of tetracycline was 3.2 mg / L, and the removal rate was 84%.

[0053] Example 3

[0054] The water sample was wastewater from a fertilizer and feed factory. The nuclear crystallization-advanced oxidation coupling process was used to synergistically remove high-concentration fluoride ions and organic matter in the wastewater. The concentration of fluoride ions in the wastewater was 100 mg / L, and the organic matter was tetracycline with a concentration of 20 mg / L.

[0055] The treatment of the above-mentioned wastewater includes the following steps: filling fluorite into the inner cylinder 4 of the nuclear crystal granulation device, the filling amount of fluorite is 2.2 g / L, adjusting the water inlet pump flow to 20 L / h, the dosing pump flow to 2.4 L / h, and adjusting the pH of the inlet water to 8; using a peristaltic pump to introduce water through the water inlet pipe 1 and the dosing pipe 3 and adding chemicals, so that the garnet is in a fluidized state in the inner cylinder 4, wherein the amount of precipitant added to the reaction system is 140 mg / L, and the amount of oxidant added is 5 mmol / L; finally, the wastewater after the reaction overflows through the toothed overflow weir 7 and flows out of the reaction system from the outlet 6.

[0056] refer to Figure 2 After the above process treatment, the concentration of fluoride ions in the effluent was 9.3 mg / L, and the removal rate was 90.7%; the concentration of tetracycline was 3 mg / L, and the removal rate was 85%.

[0057] Example 4

[0058] The water sample was wastewater from a fertilizer and feed factory. The nuclear crystallization-advanced oxidation coupling process was used to synergistically remove high-concentration fluoride ions and organic matter in the wastewater. The concentration of fluoride ions in the wastewater was 100 mg / L, and the organic matter was tetracycline with a concentration of 20 mg / L.

[0059] The treatment of the above-mentioned wastewater includes the following steps: filling calcite into the inner cylinder 4 of the nuclear crystal granulation device, the filling amount of calcite is 1.8 g / L, adjusting the water inlet pump flow to 22 L / h, the dosing pump flow to 2.5 L / h, and adjusting the pH of the inlet water to 7.5; using a peristaltic pump to introduce water through the water inlet pipe 1 and the dosing pipe 3 and adding chemicals, so that the garnet is in a fluidized state in the inner cylinder 4, wherein the amount of precipitant added to the reaction system is 160 mg / L, and the amount of oxidant added is 6 mmol / L; finally, the wastewater after the reaction overflows through the toothed overflow weir 7 and flows out of the reaction system from the outlet 6.

[0060] refer to Figure 2 After the above process treatment, the concentration of fluoride ions in the effluent was 6.3 mg / L, and the removal rate was 93.7%; the concentration of tetracycline was 2.6 mg / L, and the removal rate was 87%.

[0061] In summary, the present invention utilizes the synergistic effect between nucleation granulation and catalytic oxidation to achieve the removal of difficult-to-degrade organic matter in wastewater and the resource recovery and utilization of fluoride ions, thereby greatly improving the wastewater treatment efficiency while reducing the wastewater treatment cost.

[0062] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A nuclear crystal granulation-advanced oxidation coupling process for synergistically removing high-concentration fluoride ions and refractory organic matter in wastewater, characterized in that: include: Adding a crystal-inducing carrier, a precipitant and an oxidant into the wastewater; the precipitant is calcium chloride; Adjust the water chemical conditions and hydraulic parameters so that the crystal-inducing carrier is suspended in the inner cylinder of the nuclear crystal granulation device, thereby inducing the fluoride ions in the water to crystallize and precipitate on its surface; The nucleus crystal granulation device comprises an outer cylinder and an inner cylinder, wherein the inner cylinder is suspended in the outer cylinder and connected from top to bottom, the outlets of the water inlet pipe and the dosing pipe are both located below the inner cylinder, a toothed overflow weir and a water outlet pipe are arranged on the top of the outer cylinder, and a crystal inducing carrier discharge pipe is arranged at the bottom; Raw water enters the inner cylinder through the water inlet pipe, and the precipitant and oxidant enter the inner cylinder through the dosing pipe. During the reaction, high-concentration fluoride ions and calcium ions generate calcium fluoride crystals attached to the surface of the seed crystals under the action of chemical bonding. At the same time, the adsorption sites on the surface of the crystal-inducing carrier adsorb the difficult-to-degrade organic matter, and under the action of the catalytic sites on its surface, the oxidant is catalytically activated to generate highly active free radicals, which catalytically degrade the adsorbed organic matter. As the reaction proceeds, the crystals grow to form large particles that settle at the bottom of the nuclear crystal granulation device and are discharged through the crystal-inducing carrier discharge pipe. The treated water is discharged from the water outlet pipe through the toothed overflow weir.

2. The nuclear crystal granulation-advanced oxidation coupling process for synergistically removing high-concentration fluoride ions and refractory organic matter in wastewater according to claim 1, characterized in that: The dosage of the crystal-inducing carrier is 0.6-2.2 g / L, the dosage of the precipitant is 90-160 mg / L, and the dosage of the oxidant is controlled at 1-6 mmol / L.

3. The nuclear crystal granulation-advanced oxidation coupling process for synergistically removing high-concentration fluoride ions and refractory organic matter in wastewater according to claim 1, characterized in that: The crystal-inducing carrier is garnet, calcite or fluorite, and the oxidant is one or more of hydrogen peroxide, persulfate or peroxydisulfate.

4. The nuclear crystal granulation-advanced oxidation coupling process for synergistically removing high-concentration fluoride ions and refractory organic matter in wastewater according to claim 3, characterized in that: The particle sizes of the garnet, calcite and fluorite are 180-250 μm; the garnet, calcite and fluorite need to be washed with ultrapure water and dried in an oven before use, and their surfaces are activated after drying.

5. The nuclear crystal granulation-advanced oxidation coupling process for synergistically removing high-concentration fluoride ions and refractory organic matter in wastewater according to claim 1, characterized in that: The control of water chemical conditions and hydraulic parameters includes: Control the water flow rate in the reaction system to 15-22 L / h and the pH to 6-8; The dosing flow rate is 2-2.5L / h, and the reagents are precipitants and oxidants; By regulating the water inlet and drug addition flow rates between the fluidization velocity and the carry-out velocity, it is ensured that the velocity of the fluid passing through the crystal-inducing carrier bed is not lower than the minimum velocity causing the bed to expand, that is, the difference between the actual flow velocity of the fluid in the bed and the sedimentation velocity of the crystal-inducing carrier in the vertical direction caused by gravity is greater than 0, thereby allowing the crystal-inducing carrier to be suspended in the inner cylinder of the nuclear crystal granulation device.

6. The nuclear crystal granulation-advanced oxidation coupling process for synergistically removing high-concentration fluoride ions and refractory organic matter in wastewater according to claim 1, characterized in that: A water distributor is arranged directly below the inner cylinder.

7. The nuclear crystal granulation-advanced oxidation coupling process for synergistically removing high-concentration fluoride ions and refractory organic matter in wastewater according to claim 1, characterized in that: The precipitant and the oxidant are prepared in a dosing cartridge, and the preparation concentration is comprehensively considered based on the dosing concentration and the flow rate of the peristaltic pump: when the dosing concentration increases and the flow rate of the peristaltic pump remains unchanged, the preparation concentration of the agent is increased; when the dosing concentration decreases and the flow rate of the peristaltic pump remains unchanged, the preparation concentration of the agent is decreased; when the dosing concentration remains unchanged and the flow rate of the peristaltic pump increases, the preparation concentration of the agent is decreased; when the dosing concentration remains unchanged and the flow rate of the peristaltic pump decreases, the preparation concentration of the agent is increased; when the dosing concentration remains unchanged and the flow rate of the peristaltic pump decreases, the preparation concentration of the agent is increased; when the dosing concentration is not changed, the preparation concentration of the agent is increased. When the concentration of the drug changes and the flow rate of the peristaltic pump increases, the concentration of the drug preparation is lowered; when the concentration of the drug remains unchanged and the flow rate of the peristaltic pump decreases, the concentration of the drug preparation is increased; when the concentration of the drug increases and the flow rate of the peristaltic pump increases, the concentration of the drug preparation is maintained unchanged; when the concentration of the drug increases and the flow rate of the peristaltic pump decreases, the concentration of the drug preparation is increased; when the concentration of the drug decreases and the flow rate of the peristaltic pump increases, the concentration of the drug preparation is lowered; when the concentration of the drug decreases and the flow rate of the peristaltic pump decreases, the concentration of the drug preparation is maintained unchanged.

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