A treatment method of high-concentration ammonium fluoride wastewater in electronic industry

Abstract

This invention discloses a method for treating high-concentration ammonium fluoride wastewater from the electronics industry. Specifically, the method involves: first, induced crystallization for fluoride resource recovery to remove fluoride from the wastewater; then, enzymatic decomposition of hydrogen peroxide to remove hydrogen peroxide; and finally, integrated anaerobic ammonia oxidation to remove ammonia nitrogen. This invention employs a combined process of "induced crystallization for fluoride resource recovery + enzymatic decomposition of hydrogen peroxide + integrated anaerobic ammonia oxidation." By simultaneously achieving fluoride removal and fluoride resource recovery through induced crystallization, and efficiently removing hydrogen peroxide through enzymatic reaction, the invention achieves high-efficiency treatment of high-ammonia nitrogen wastewater under low-energy conditions through a short-cut nitrification-anaerobic ammonia oxidation process. This solves the problems of high reagent consumption, high sludge production, high operating costs, and low ammonia nitrogen removal rate inherent in traditional ammonium fluoride wastewater treatment processes (stripping + chemical coagulation).

Description

Technical Field

[0001] This invention relates to a method for treating high-concentration ammonium fluoride wastewater from the electronics industry. Background Technology

[0002] The electronics industry generates substantial volumes of high-concentration ammonium fluoride wastewater during production. The main pollutants are fluoride, ammonia nitrogen, and hydrogen peroxide, with fluoride and ammonia nitrogen concentrations ranging from 1 to 10 g / L. Currently, the treatment process for this high-concentration ammonium fluoride wastewater in the electronics industry involves stripping followed by chemical coagulation. This process first removes ammonia nitrogen through stripping, then removes fluoride through chemical coagulation. However, due to limitations in wastewater properties, this process suffers from low ammonia nitrogen removal rates (70-85%), secondary pollution (ammonium sulfate, fluoride-containing sludge), high reagent consumption, and high operating costs. Summary of the Invention

[0003] Purpose of the invention: The purpose of this invention is to provide a method for treating high-concentration ammonium fluoride wastewater in the electronics industry. This method can simultaneously remove fluoride, ammonia nitrogen, and hydrogen peroxide from the wastewater, and significantly improves the ammonia nitrogen removal efficiency by using a Bio-Manam reactor, achieving a removal rate of over 95%.

[0004] Technical solution: The method for treating high-concentration ammonium fluoride wastewater in the electronics industry according to the present invention specifically comprises: firstly, inducing crystallization fluoride resource recovery treatment to remove fluoride from the wastewater while realizing fluoride resource recovery; then, enzymatic catalytic decomposition of hydrogen peroxide treatment to remove hydrogen peroxide from the wastewater; and finally, integrated anaerobic ammonia oxidation treatment to remove ammonia nitrogen from the wastewater.

[0005] The integrated anaerobic ammonia oxidation process utilizes a Bio-Manam reactor, which is equipped with a Manam membrane module. The Manam membrane fibers used in the Manam membrane module are prepared using the following method:

[0006] (1) Place the PVDF hollow fiber membrane (nominal pore size 0.1μm) in a NaOH solution with pH 9.0 and soak for 2 hours (to clean the coating or impurities on the surface of the PVDF membrane); after soaking, rinse the outside of the PVDF hollow fiber membrane with deionized water for 30 minutes and then air dry at room temperature;

[0007] (2) Dissolve polydimethylsiloxane (PDMS) in n-hexane to prepare a PDMS solution with a mass fraction of 5-9%; immerse the PVDF hollow fiber membrane in the PDMS solution and circulate it for 6-10 hours; after circulation, drain the PDMS solution and rinse with deionized water for 60 minutes; after rinsing, place it in an environment of 70-85℃ for curing for 10-16 hours; PDMS is loaded as an oxygen-permeable coating on the outside of the PVDF membrane (outside the PVDF membrane tube wall). When the PDMS layer is ventilated inside the PVDF membrane, it transfers oxygen to the water and prevents water from entering the PVDF membrane fibers;

[0008] (3) First, prepare a triaminomethane-hydrochloric acid buffer solution with a concentration of 10-20 mmol / L; dissolve dopamine hydrochloride (DOPA) and persulfate in the triaminomethane-hydrochloric acid buffer solution to prepare a DOPA solution with a concentration of 1-10 mg / L. In the DOPA solution, n(persulfate):n(DOPA) = 1.0-1.1; persulfate is a strong oxidizing agent that can oxidize DOPA to dopamine.

[0009] (4) The PVDF hollow fiber membrane obtained in step (2) was soaked in DOPA solutions with concentrations of 1, 2, 5, and 10 mg / L in sequence (the purpose of soaking in sequence is to obtain DOPA layers of different thicknesses and contents on the outside of the PVDF hollow fiber membrane, so as to improve its biocompatibility and at the same time, the DOPA layer can serve as a carbon source during the biofilm attachment process, greatly enhancing the attachment and growth ability of microorganisms on the outside of the membrane) for 1 to 3 hours respectively; after drying, the membrane fibers were rinsed with deionized water for 30 minutes to obtain Manam membrane fibers.

[0010] This invention modifies PVDF membranes using the aforementioned methods, effectively improving biofilm attachment rates. This is because the highly biocompatible environment created by the DOPA layer is conducive to microbial attachment and growth, while PDMS increases the oxygen transfer concentration on the membrane's outer surface, thus effectively accelerating the enrichment of functional bacteria such as AOB and AnAOB. ​​Therefore, the PDMS-modified membrane fibers possess an asymmetric wetting structure with one hydrophilic side and the other hydrophobic side, significantly enhancing the hydrophilicity of the outer surface. This allows the biofilm to attach more quickly to the membrane surface while improving the oxygen transfer efficiency of the membrane fibers and effectively extending their lifespan (preventing water from seeping into the inner surface of the membrane fibers, reducing the possibility of water penetration, and thus improving membrane lifespan). The Bio-Manam reactor using Manam membrane modules has advantages such as short start-up cycles, good treatment effects, and strong shock resistance, thereby rapidly achieving low-consumption and high-efficiency removal of high-concentration ammonia nitrogen.

[0011] The Bio-Manam reactor contains at least one layer of Manam membrane modules. Each layer of Manam membrane modules contains multiple sets of Manam membrane modules arranged in parallel. Each set of membrane modules includes an air inlet, an air distributor, Manam membrane fibers, a waste gas collection chamber, and an air outlet. Gas enters the air distributor through the air inlet, which delivers the gas to the multiple hollow Manam membrane fibers arranged in parallel. The waste gas after the reaction enters the waste gas collection chamber and is discharged from the membrane module through the air outlet. The Bio-Manam reactor also includes a water inlet at the bottom of the reactor, a water outlet at the top of the reactor, an air inlet main pipe connected to an external aeration device, and an exhaust main pipe for discharging waste gas from the reactor. The air inlet of each set of membrane modules is connected to the air inlet main pipe of the reactor, and the air outlet of each set of membrane modules is connected to the exhaust main pipe of the reactor.

[0012] The Manam membrane modules are placed at a density of 270–320 m³ / g in the reactor. 2 / m 3 The reactor can be freely combined according to its size, and multiple Manam membrane modules can be placed according to the reactor height. The wastewater inlet is located at the bottom of the reactor, and wastewater flows through the reactor from bottom to top. The reactor is also equipped with acid and alkali dosing pipelines. The acidic agent is 10% sulfuric acid, and the alkali agent is a mixed solution of NaOH and Na2CO3, both with a mass concentration of 10%. An online pH meter is also installed inside the reactor to control the acid and alkali dosing, maintaining the pH inside the reactor at 7.0–7.7. An online DO meter is also installed inside the reactor to control the aeration rate, maintaining the DO inside the reactor at 0.10–0.18 mg / L. The online pH and DO meters are located in the upper part of the reactor's sludge zone.

[0013] Due to the bubble-free aeration and anisotropic mass transfer of Manam membrane fibers, coupled with the presence of mass transfer resistance, a gradient distribution of oxygen and pollutant concentrations occurs within the biofilm, resulting in a stratified structure. In the inner layer of the biofilm, high oxygen content favors the accumulation of autotrophic nitrifying bacteria, and ammonia nitrogen infiltrating into the membrane from the water is converted into nitrite nitrogen. In the outermost layer of the biofilm, dissolved oxygen concentration is lowest, while ammonia nitrogen is abundant, suitable for anaerobic ammonia oxidation. The nitrogen gas produced in the reaction is transferred to the water, completing the removal of nitrogen pollutants. Air enters the reactor through the Manam membrane fibers, forming an aerobic biofilm near the fibers and an anaerobic biofilm further away.

[0014] During the operation of the Bio-Manam reactor, an anaerobic ammonia oxidation enhancement agent (EnAnam) was continuously added at a dosage of 1 L / m³. 3(One liter of reagent is added per cubic meter of wastewater); the formulation of the anaerobic ammonia oxidation enhancement reagent is: 0.6 mol / L fulvic acid, 0.3 mol / L boric acid, 0.05 mol / L magnesium chloride, and 0.05 mol / L ferric chloride. The fulvic acid and boric acid in EnAnam can increase the EPS production of AnAOB bacteria, increase the rate of signal factor generation, enhance the "quorum sensing" effect, and improve denitrification efficiency.

[0015] In this process, trace element reagents were continuously added to the influent conditioning tank of the Bio-Manam reactor at a dosage of 0.5 L / m³. 3 The formula for the trace element reagent is: CuSO4 200mg / L, Na2MO4 100mg / L and MnSO4 150mg / L.

[0016] The inlet water regulating tank is equipped with a heating pipe, and the Bio-Manam reactor is equipped with an insulation layer to control the internal temperature of the Bio-Manam reactor to be 31-34°C during operation.

[0017] Specifically, the induced crystallization fluorine resource recovery process involves using an induced crystallization fluidized bed reactor for fluorine resource recovery; fluorite seed crystals are added to the reactor at a rate of 30–40 kg / m³. 2 (Add 30-40 kg of seed crystals per square meter of reactor cross-section), with a seed crystal particle size of 100-120 mesh; reactor influent load is 3.6-4.5 kgF / m². 2 The flow rate is 7–14 m / h. An online pH meter is installed inside the reactor. During operation, composite calcium salt is added to control the internal pH at 5.5–6.7, the Ca / F ratio at 0.50–0.56, and the seed crystal residence time in the reactor at 5–8 days. Adjusting the reaction pH induces crystallization to form fluorite. Compared to existing induced crystallization defluorination technologies, directly adding composite calcium salt to the reactor eliminates the need for pre-addition of liquid alkali to adjust the pH, reducing the number of upstream reactors, simplifying the process, and preventing the volatilization of high-concentration ammonia into the air after pH adjustment.

[0018] The enzyme-catalyzed decomposition of hydrogen peroxide specifically involves: the effluent from the induced crystallization fluidized bed reactor entering the reaction tank, adding an enzyme (hydrogen peroxide catalytic decomposition enzyme) to the reaction tank, with an addition amount of m(enzyme):m(H2O2) = 0.2–0.3, and stirring the reaction for 45–60 minutes.

[0019] In this process, after H2O2 is removed in the reaction tank, the wastewater enters the activated carbon filter for further removal of H2O2. The residual H2O2 concentration in the effluent from the activated carbon filter is less than 0.1 mg / L.

[0020] Beneficial Effects: Compared with existing technologies, this invention has the following significant advantages: This invention adopts a combined process of "induced crystallization fluoride resource recovery + enzyme-catalyzed hydrogen peroxide decomposition + integrated anaerobic ammonia oxidation." It efficiently removes hydrogen peroxide through enzymatic reactions, simultaneously achieves fluoride removal and fluoride resource recovery and reuse through induced crystallization, and achieves efficient treatment of high ammonia nitrogen wastewater under low energy consumption conditions through a short-cut nitrification-anaerobic ammonia oxidation process. This solves the problems of high reagent consumption, high sludge production, high operating costs, and low ammonia nitrogen removal rate inherent in traditional ammonium fluoride wastewater treatment processes (stripping + chemical coagulation). Specifically, it addresses the same influent conditions (influent ammonia nitrogen concentration 700–1000 mg NH₄⁻). 4+ Using the process of this invention, the biofilm thickness on the membrane filaments is significantly increased, the biomass per unit volume increases from 1.0–1.3 g / L to 3.5–4.5 g / L, and the nitrogen removal load increases from 0.3 kg N / (m³). 3 ·d) Increase to 1.0~1.6kgN / (m 3 ·d), the ammonia nitrogen in the effluent decreased from 200-320 mg / L to below 80 mg / L. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the Bio-Manm reactor and membrane module of the present invention;

[0022] Figure 2 This is a schematic diagram illustrating the principle of anaerobic ammonia oxidation in the Bio-Manm reactor of the present invention.

[0023] Figure 3 This is a process flow diagram of the processing method of the present invention. Detailed Implementation

[0024] like Figures 1-2 As shown, the Bio-Manam reactor 3 of the present invention is provided with at least one layer of Manam membrane module 2; each layer of Manam membrane module contains multiple sets of Manam membrane modules 2 arranged in parallel, each set of membrane module 2 includes an inlet 2-2, an inlet distributor 2-3, Manam membrane fibers 2-1, a waste gas collection chamber 2-5, and an outlet 2-4. Gas enters the inlet distributor 2-3 through the inlet 2-2, and the inlet distributor 2-3 delivers the gas to multiple hollow Manam membrane fibers 2-1 arranged in parallel. After the reaction... The waste gas enters the waste gas collection chamber 2-5 and is discharged from the membrane module through the outlet 2-4; the Bio-Manam reactor 3 also includes an inlet 3-2 at the bottom of the reactor, an outlet 3-3 at the top of the reactor, an air inlet main pipe 3-4 connected to an external aeration device, and an exhaust main pipe 3-5 for discharging waste gas from the reactor; the air inlet 2-2 of each Manam membrane module 2 is connected to the air inlet main pipe 3-4 of the reactor, and the air outlet 2-4 of each Manam membrane module 2 is connected to the exhaust main pipe 3-5 of the reactor.

[0025] Manam membrane module 2 is placed in Bio-Manam reactor 3 at a density of 270–320 m³ / g. 2 / m 3 The reactor can be freely combined according to its size, and multiple Manam membrane modules can be placed according to the reactor height. The wastewater inlet is located at the bottom of the reactor, and wastewater flows through the reactor from bottom to top. The reactor is also equipped with acid and alkali dosing pipelines. The acidic agent is 10% sulfuric acid, and the alkali agent is a mixed solution of NaOH and Na2CO3, both with a mass concentration of 10%. An online pH meter is also installed inside the reactor to control the acid and alkali dosing, maintaining the pH inside the reactor at 7.0–7.7. An online DO meter is also installed inside the reactor to control the aeration rate, maintaining the DO inside the reactor at 0.10–0.18 mg / L. The online pH and DO meters are located in the upper part of the reactor's sludge zone.

[0026] The Manam membrane fibers used in the Manam membrane module of this invention are prepared by the following method:

[0027] (1) Place the PVDF hollow fiber membrane (nominal pore size 0.1μm) in a NaOH solution with pH 9.0 and soak for 2 hours (to clean the coating or impurities on the surface of the PVDF membrane); after soaking, rinse the outside of the PVDF hollow fiber membrane with deionized water for 30 minutes and then air dry at room temperature;

[0028] (2) Dissolve polydimethylsiloxane (PDMS) in n-hexane to prepare a 5% PDMS solution; immerse the PVDF hollow fiber membrane in the PDMS solution and circulate it for 8 hours; after circulation, drain the PDMS solution and rinse with deionized water for 60 minutes; after rinsing, place it in an 80°C environment for curing for 10 hours; PDMS is loaded as an oxygen-permeable coating on the outside of the PVDF membrane (outside the PVDF membrane tube wall). When the PDMS layer is ventilated inside the PVDF membrane, it transfers oxygen to the water and prevents water from penetrating into the PVDF membrane fibers; thus, a PVDF hollow fiber membrane with a PDMS layer loaded on the outside of the tube wall is obtained.

[0029] (3) First, prepare a 10 mmol / L triaminomethane-hydrochloric acid buffer solution; dissolve dopamine hydrochloride (DOPA) and persulfate in the triaminomethane-hydrochloric acid buffer solution to prepare DOPA solutions with concentrations of 1, 2, 5, and 10 mg / L, respectively. In each concentration of DOPA solution, n(persulfate):n(DOPA) = 1.0 to 1.1.

[0030] (4) The PVDF hollow fiber membrane obtained in step (2) was soaked in DOPA solutions with concentrations of 1, 2, 5, and 10 mg / L in sequence (the purpose of soaking in sequence is to obtain DOPA layers of different thicknesses and contents on the outside of the PVDF hollow fiber membrane, so as to improve its biocompatibility and at the same time, the DOPA layer can serve as a carbon source during the biofilm attachment process, greatly enhancing the attachment and growth ability of microorganisms on the outside of the membrane) for 2 hours respectively; after drying, the membrane fibers were rinsed with deionized water for 30 minutes to obtain Manam membrane fibers.

[0031] Each Manam membrane filament in Manam membrane module 2 includes a support layer 1-1 with a hollow mesh structure, a PVDF membrane layer 1-2 fixed on the support layer 1-1, and a PDMS modified layer 1-3 loaded on the PVDF membrane layer 1-2 (the DOPA layer outside the PDMS modified layer 1-3 has been consumed as a carbon source during biofilm attachment).

[0032] Example 1

[0033] A chip factory has 12m³ of high-concentration ammonium fluoride wastewater. 3 The water quality is shown in the table below for / d:

[0034] Table 1 shows the water quality of high-concentration ammonium fluoride wastewater from a chip factory.

[0035] pH <![CDATA[NH3-N(mg / L)]]> F (mg / L) <![CDATA[H2O2(mg / L)]]> TOC (mg / L) ＜0.5 2000～3000 2000～3000 1500～4000 ＜10

[0036] The above-mentioned ammonium fluoride wastewater is treated using the method of the present invention, such as... Figure 3 As shown, the specific steps include the following:

[0037] (1) Water quality and quantity adjustment: High-concentration ammonium fluoride wastewater first enters the wastewater adjustment tank and is mixed with other wastewater (low-concentration fluoride wastewater) at a flow ratio of 1:2.

[0038] (2) Fluorine resource recovery treatment by induced crystallization: Ammonium fluoride wastewater enters the fluidized bed influent equalization tank from the wastewater equalization tank, and then enters the induced crystallization fluidized bed reactor for fluorine resource recovery treatment; fluorite seed crystals are added to the reactor at a rate of 30 kg / m³. 2 The seed crystal size is 100–120 mesh; the reactor influent load is 4.0–4.4 kgF / m³. 2The flow rate is 9–13 m / h. The reactor is equipped with an online pH meter. During operation, liquid alkali and a composite calcium salt are added. The composite calcium salt is a mixed solution of Ca(OH)₂ and CaCl₂, with n(Ca(OH)₂):n(CaCl₂) = 1–1.14. The internal pH of the reactor is controlled at 5.5–6.5, and the Ca / F ratio is 0.54. The seed crystals remain in the reactor for 7 days. The induced crystallization fluidized bed reactor is equipped with a waste gas collection system. The ammonia-containing waste gas generated during reactor operation is treated in the plant's waste gas treatment system.

[0039] (3) Hydrogen peroxide catalytic decomposition treatment: The effluent from the induced crystallization fluidized bed reactor enters the reaction tank, and an enzyme (hydrogen peroxide catalytic decomposition enzyme) is added to the reaction tank. The dosage is m(enzyme):m(H2O2) = 0.2~0.3. The reaction is stirred for 45 min. After the reaction, the residual concentration of H2O2 is less than 2 mg / L.

[0040] (4) Activated carbon filtration: The wastewater after H2O2 removal in the reaction tank enters the activated carbon filter. The activated carbon filter removes H2O2 in depth. No H2O2 was detected in the effluent from the activated carbon filter.

[0041] (5) Integrated anaerobic ammonia oxidation treatment: The effluent from the activated carbon filter enters the influent conditioning tank of the integrated anaerobic ammonia oxidation reactor (Bio-Manam), and then enters the Bio-Manam reactor; trace element reagents (the formula of the trace element reagents is: CuSO4 200mg / L, Na2MO4 100mg / L and MnSO4 150mg / L) are continuously added to the influent conditioning tank of the Bio-Manam reactor at a dosage of 0.5L / m³. 3 The equalization tank is equipped with heating pipes, and the Bio-Manam reactor is equipped with an insulation layer to control the internal temperature of the Bio-Manam reactor to be 31-34℃ during operation.

[0042] Bio-Manam reactor volumetric loading: 1.22 kgN / (m³) 3 •d); The Bio-Manam reactor is equipped with Manam membrane modules at the bottom, with a height of 2.4m and a placement density of 290m³ / s. 2 / m 3The reactor is equipped with an online pH meter to control acid and alkali dosing, maintaining the pH within the reactor at 7.0–7.7. It also has an online DO meter to control aeration, maintaining DO levels at 0.10–0.18 mg / L. The online pH and DO meters are located at the top of the reactor. A circulating pump controls the upward flow velocity of the liquid within the reactor, maintaining it at 3.0–4.5 m / h. During operation, the Bio-Manam reactor continuously adds an anaerobic ammonia oxidation enhancer (EnAnam) at a dosage of 1 L / m³. 3 The formulation of the anaerobic ammonia oxidation enhancer is as follows: fulvic acid 0.6 mol / L, boric acid 0.3 mol / L, magnesium chloride 0.05 mol / L and ferric chloride 0.05 mol / L.

[0043] Table 2 shows the effluent water quality of each unit in the treatment process of Example 1.

[0044]

Claims

1. A method for treating high-concentration ammonium fluoride wastewater from the electronics industry, characterized in that, Specifically, the method first performs induced crystallization fluorine resource recovery treatment to remove fluoride from the wastewater; then performs enzyme-catalyzed decomposition of hydrogen peroxide treatment to remove hydrogen peroxide from the wastewater; and finally performs integrated anaerobic ammonia oxidation treatment to remove ammonia nitrogen from the wastewater. The integrated anaerobic ammonia oxidation process utilizes a Bio-Manam reactor, which contains at least one layer of Manam membrane modules. Each layer contains multiple sets of parallel-arranged Manam membrane modules. Each set includes an inlet, an inlet distributor, Manam membrane fibers, a waste gas collection chamber, and an outlet. Gas enters the inlet distributor through the inlet, which then distributes the gas to the multiple parallel-arranged hollow Manam membrane fibers. The reacted waste gas enters the waste gas collection chamber and exits from the outlet. The Bio-Manam reactor also features acid and alkali dosing lines, an online pH meter, and an online DO meter, maintaining the pH at 7.0–7.7 and the DO at 0.10–0.20 mg / L during operation. Anaerobic ammonia oxidation enhancement agents are continuously added to the Bio-Manam reactor at a dosage of 1 L / m³. 3 The formulation of the anaerobic ammonia oxidation enhancement agent is as follows: fulvic acid 0.6 mol / L, boric acid 0.3 mol / L, magnesium chloride 0.05 mol / L, and ferric chloride 0.05 mol / L; the Manam membrane fiber used in the Manam membrane module is prepared by the following method: (1) Soak the PVDF hollow fiber membrane in NaOH solution; after soaking, rinse the PVDF hollow fiber membrane with deionized water and then air dry at room temperature; (2) Dissolve polydimethylsiloxane in n-hexane to prepare a PDMS solution with a mass fraction of 5-9%; immerse the PVDF hollow fiber membrane in the PDMS solution and circulate it for 6-10 hours; after circulation, drain the PDMS solution, dry it and rinse it with deionized water; after rinsing, cure it at high temperature; and obtain a PVDF hollow fiber membrane with a PDMS layer loaded on the outside of the tube wall. (3) First, prepare a triaminomethane-hydrochloric acid buffer solution; dissolve dopamine hydrochloride and persulfate in the above triaminomethane-hydrochloric acid buffer solution to prepare a DOPA solution with a concentration of 1~10 mg / L. In the DOPA solution, n(persulfate):n(DOPA) = 1.0~1.1; (4) The PVDF hollow fiber membrane obtained in step (2) is successively immersed in DOPA solutions with concentrations of 1, 2, 5 and 10 mg / L for 1 to 3 hours respectively; after drying, deionized water is passed through to rinse the membrane fibers to obtain Manam membrane fibers.

2. The method for treating high-concentration ammonium fluoride wastewater from the electronics industry according to claim 1, characterized in that: In step (2), after rinsing, the product is placed in an environment of 70~85℃ for curing for 10~16h.

3. The method for treating high-concentration ammonium fluoride wastewater from the electronics industry according to claim 1, characterized in that: The Bio-Manam reactor also includes an inlet located at the bottom of the reactor, an outlet located at the top of the reactor, an air intake pipe connected to an external aeration device, and an exhaust pipe for discharging waste gas from the reactor; the air inlet of each membrane module is connected to the air intake pipe of the reactor, and the air outlet of each membrane module is connected to the exhaust pipe of the reactor.

4. The method for treating high-concentration ammonium fluoride wastewater from the electronics industry according to claim 1, characterized in that: Trace element reagents were continuously added to the influent equalization tank of the Bio-Manam reactor at a dosage of 0.5 L / m³. 3 The formula for the trace element reagent is: CuSO4 200mg / L, NaCl 100mg / L, Na2MO4 100mg / L and MnSO4 150mg / L.

5. The method for treating high-concentration ammonium fluoride wastewater from the electronics industry according to claim 4, characterized in that: The inlet regulating tank is equipped with heating pipes, and the Bio-Manam reactor is equipped with an insulation layer to control the internal temperature of the Bio-Manam reactor to be 31~34℃ during operation.

6. The method for treating high-concentration ammonium fluoride wastewater from the electronics industry according to claim 1, characterized in that: The induced crystallization fluorine resource recovery process specifically involves: using an induced crystallization fluidized bed reactor for fluorine resource recovery; adding fluorite seed crystals to the reactor at a rate of 30-40 kg / m³. 2 The seed crystal size is 100~120 mesh; the reactor influent load is 3.6~4.5 kgF / (m³). 2 The flow rate is 12-14 m / h. The reactor is equipped with an online pH monitoring instrument. During reactor operation, liquid alkali and compound calcium salt are added to control the internal pH of the reactor to 5.5-6.7, the Ca / F ratio to 0.50-0.56, and the seed crystals to remain in the reactor for 5-8 days. The pH of the reaction is adjusted to induce crystallization and generate fluorite.

7. The method for treating high-concentration ammonium fluoride wastewater from the electronics industry according to claim 1, characterized in that: The enzyme-catalyzed decomposition of hydrogen peroxide treatment is specifically as follows: the effluent from the induced crystallization fluidized bed reactor enters the reaction tank, an enzyme is added to the reaction tank, the dosage is m(enzyme):m(H2O2) = 0.2~0.3, and the reaction is stirred for 45~60 min.

8. The method for treating high-concentration ammonium fluoride wastewater from the electronics industry according to claim 7, characterized in that: After H2O2 is removed in the reaction tank, the wastewater enters the activated carbon filter for further removal of H2O2.

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