An ultrasonic coupling electrochemical pretreatment device and method for high-concentration antibiotic production wastewater

Abstract

This invention belongs to the field of pharmaceutical wastewater treatment technology, and particularly relates to an ultrasonic-coupled electrochemical pretreatment device and method for high-concentration antibiotic production wastewater. The device consists of an ultrasonic treatment first reactor, an electrochemical second reactor, and a flocculation sedimentation third reactor connected in series via pipelines. The first reactor is equipped with a wall-mounted ultrasonic transducer; the second reactor contains a stabilizing electrode and a sacrificial electrode, and multiple disc aerators are installed at the bottom; the third reactor contains an overflow trough, inclined tube packing, and an electromagnet. This invention can achieve efficient desorption and mineralization degradation of adsorbed antibiotics in suspended solids in production wastewater, reduce antibiotic and degradation product residues in flocs, and eliminate toxic effects on subsequent biological treatment processes.

Description

Technical Field

[0001] This invention belongs to the field of pharmaceutical wastewater treatment technology, and particularly relates to an ultrasonic-coupled electrochemical pretreatment device and method for high-concentration antibiotic production wastewater. Background Technology

[0002] Wastewater from fermentation-based antibiotic production is characterized by complex composition, high suspended solids, high salinity, high COD, and strong biotoxicity. Pretreatment technologies for fermentation-based pharmaceutical wastewater in my country mainly include multi-effect evaporation and steam mechanical recompression for high-salinity wastewater, stripping and vapor stripping for wastewater with high NH3-N (>1000 mg / L), and coagulation sedimentation and flotation for wastewater with high suspended solids (>500 mg / L). The main treatment technologies are anaerobic and aerobic biological treatment. Advanced treatment technologies include coagulation sedimentation, flotation, Fenton oxidation, and ozone oxidation + aerated biological filter, ozone oxidation + membrane bioreactor, etc. Pretreatment of chemically synthesized pharmaceutical wastewater, in addition to the above-mentioned technologies for high-salinity and high-NH3-N wastewater, also includes technologies for wastewater with poor biodegradability (BOD5 / COD ratio). Cr <0.3) Wastewater treatment technologies such as iron-carbon micro-electrolysis and Fenton oxidation, COD Cr Removal rates can reach 20%–50%, BOD5 / COD Cr >0.3; The main treatment and advanced treatment technologies are not significantly different from those for fermentation-based pharmaceutical wastewater. Because pretreatment technologies struggle to achieve efficient mineralization and removal of residual antibiotics in wastewater, subsequent biological treatment is highly unstable and can induce antibiotic-resistant bacteria (ARBs) and resistance genes (ARGs). Electrocoagulation is a method that uses alternating current or direct current to treat wastewater. It utilizes metal cations generated by sacrificial anodes (made of stainless steel, iron, aluminum, etc.) to flocculate and precipitate pollutants into sludge. Pollutant removal can also be achieved through the oxidation / reduction of the electrodes. It is currently applied to the treatment of antibiotic-containing wastewater.

[0003] Patent CN114212862A discloses an integrated electrocoagulation and oxidation method for treating antibiotic-containing wastewater. It uses an inert material (one of BDD, RuO2, TiO2, SnO2, and titanium-coated ruthenium electrodes) as the anode and an aluminum, magnesium, and zinc cathode as the cathode. The method utilizes anodic oxidation and indirect electrocoagulation at the cathode to simultaneously remove turbidity, chloramphenicol, and sulfamethoxazole from the wastewater. However, the high cost of removing the inert anode and the sacrifice of the cathode's weak flocculant (metal ion) precipitation ability make the applicability of this technology unclear. Patent CN114835205A discloses a heterogeneous electro-Fenton-electrocoagulation method for treating copper-ciprofloxacin complexes (Cu-CIP). It uses N-doped cobalt-iron bimetallic porous carbon as the cathode and an aluminum sheet as the anode. The method utilizes reactive oxygen free radicals generated at the cathode to break down the Cu-CIP complex and degrade CIP into smaller molecules, then removes Cu through electrocoagulation. This method has a narrow pH range (weakly acidic to neutral), and the cathode preparation method is complex and costly, making it unsuitable for large-scale treatment of high-concentration antibiotic production wastewater. Patent CN115959745A discloses a method using an iron plate or iron-containing metal plate as the anode and graphene-based Fe... n+ (GO@Fe n+ ) as a particulate electrode to synergistically activate persulfate and utilize Fe 3+ This method involves flocculation and sedimentation to completely degrade antibiotics (tetracycline hydrochloride, TCH). However, this technology is significantly affected by organic load (COD) and wastewater pH. n+ The catalytic activity was weak, and it did not significantly improve the TCH degradation rate, and it was difficult to recycle.

[0004] While existing electrocoagulation and its coupling technologies can achieve efficient pretreatment of antibiotic-containing wastewater under specific conditions, they still suffer from drawbacks such as high electrode manufacturing costs, stringent reaction condition requirements, and high residual antibiotic concentrations in the flocculated sediment. The high surface area of ​​plate electrodes easily leads to concentration polarization and electrochemical polarization, resulting in a significant amount of electrical energy being consumed on the electrode surface. Furthermore, the small electrode spacing (1–5 cm) presents challenges for cleaning and maintenance. In addition, suspended solids adsorb a large amount of antibiotics, and higher temperatures, neutral to weakly alkaline environments, and high ionic strength all promote antibiotic transfer to suspended solids, thus posing a high risk of secondary pollution during sludge resource utilization. Summary of the Invention

[0005] The purpose of this invention is to solve the problems of strong adsorption of antibiotics by high-content suspended solids in production wastewater, poor subsequent biological treatment effect of antibiotics due to difficulty in mineralization and degradation of antibiotics, high antibiotic content in sludge and the resulting high ecological risks. The invention proposes an ultrasonic-coupled electrochemical pretreatment device and method for high-concentration antibiotic production wastewater.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] An ultrasonic-coupled electrochemical pretreatment device for high-concentration antibiotic production wastewater comprises an ultrasonic treatment first reactor, an electrochemical second reactor, and a flocculation sedimentation third reactor connected in series via pipelines. The first reactor is equipped with a wall-mounted ultrasonic transducer, the second reactor has a stabilizing electrode and a sacrificial electrode, and multiple disc aerators are installed at the bottom. The third reactor is equipped with an overflow trough, inclined tube packing, and an electromagnet.

[0008] The three reactors are connected in series via pipelines, which are equipped with pipeline pumps.

[0009] The second reactor is equipped with stabilizing electrodes and sacrificial electrodes arranged in an alternating symmetrical pattern, with a spacing of 6 to 30 cm between adjacent electrodes; and a liquid injection pipe is provided along one side wall of the reactor.

[0010] The third reactor is divided into an overflow trough and a sedimentation tank by a baffle plate. The overflow trough is located on one side of the third reactor adjacent to the second reactor, and the pipeline connected to the second reactor is connected through the bottom of the overflow trough. The bottom of the sedimentation tank is provided with a sludge discharge port and is connected to a sludge pump through a pipeline. The sedimentation tank is provided with a wall-mounted electromagnet and inclined tube packing that is supported and fixed by a bracket. At the same time, a toothed drainage trough is provided above the inclined tube packing, which is fixed to the side wall of the reactor by bolts and connected to the outlet located at the top of the third reactor.

[0011] There are three reactors in total, made of PVC or fiberglass, with a volume of 0.1–10 m³. 3 The pipeline pumps are connected in series, with a flow rate of 1-10 m³ / h. 3 / h; The first reactor performs ultrasonic treatment, the second reactor simultaneously performs electrochemically enhanced heterogeneous catalytic reaction and electrocoagulation + electrocatalytic reaction, and the third reactor performs particulate electrode recovery and floc precipitation.

[0012] The wall-mounted ultrasonic transducer is made of acid and alkali resistant stainless steel or titanium, and is installed in the first reactor and connected to an ultrasonic power supply. The output frequency of the ultrasonic power supply can be adjusted from 0.1 to 200 kHz.

[0013] The stabilizing electrode and sacrificial electrode are powered by DC power supplies with an output voltage adjustment range of 0–60V; the disc aerator is made of acid and alkali resistant materials such as rubber, PP, or ABS nylon, with a working airflow of 0.05–0.2 m³ / s. 3 / h·unit, serving area 0.2~0.5m² 2 / each; the injection tube is made of PVC or PBDE material, with a diameter of 25-50mm.

[0014] The baffle plate is made of PVC or fiberglass (consistent with the reactor material); the inclined tube packing is made of PP, PVC, fiberglass, or ethylene-propylene copolymer, with a pipe diameter of 30–80 mm; the electromagnet is an insulated structure, waterproof and acid / alkali resistant, with an initial suction force of 1000–8000 N; the mud pump is self-priming, with a flow rate of 1–5 m³ / h. 3 / h.

[0015] An ultrasonic-coupled electrochemical pretreatment method for high-concentration antibiotic production wastewater using the aforementioned device is disclosed. The device utilizes ultrasonic water oxidation and mechanical shearing to desorb adsorbed antibiotics from suspended solids in the wastewater. Subsequently, the wastewater undergoes electro-enhanced heterogeneous catalytic oxidation, electrocoagulation, and electrocatalytic reactions through electrode switching, achieving deep mineralization and degradation of high-concentration antibiotics in the wastewater. This reduces the residual antibiotics and their degradation products in the flocs while eliminating the toxicity of the wastewater.

[0016] The stabilizing electrode can be made of graphite, titanium, titanium alloy, or boron-doped diamond; the sacrificial electrode can be made of iron, aluminum, or their alloys; the working airflow of the disc aerator is 0.05–0.2 m³ / s. 3 / h·unit, serving area 0.2~0.5m² 2 / indivual.

[0017] Wastewater enters the first reactor for ultrasonic treatment; then it enters the second reactor, where granular electrodes and oxidants are added. First, an electro-enhanced heterogeneous catalytic oxidation reaction is carried out with a stable electrode as the anode and a sacrificial electrode as the cathode. Then, the electrode polarity is switched to use a stable electrode as the cathode and a sacrificial electrode as the anode for electrocoagulation and electrocatalytic reactions. After electrochemical treatment, the wastewater enters the bottom of the overflow tank of the third reactor. The granular electrodes are recovered by magnetic adsorption. The suspended solids are discharged by a mud pump after sedimentation in an inclined tube for further treatment. The clarified wastewater is collected by a toothed drainage channel and discharged into a sedimentation tank for subsequent biological treatment.

[0018] The ultrasonic treatment time for the first reactor is 10–120 min;

[0019] The particulate electrode in the second reactor can be selected from one or more of cobalt tetroxide (Co3O4), cobalt ferrite (CoFe2O4), manganese ferrite (MnFe2O4), nickel cobalt ferrite (CoNiFe2O4), and zinc cobalt ferrite (CoZnFe2O4); the dosage of the particulate electrode is 0.1-10 g / L; the oxidant can be selected from one or more of persulfate (PMS), perdisulfate (PDS), hydrogen peroxide (H2O2), and peracetic acid (PAA); the dosage of the oxidant is 0.5-50 g / L.

[0020] In the second reactor, an electro-enhanced heterogeneous catalytic oxidation reaction is carried out for 15–180 min with a stable electrode as the anode and a sacrificial electrode as the cathode; then, the electrode polarity is switched to carry out electrocoagulation and electrocatalytic reactions for 15–180 min.

[0021] The wastewater takes 60–240 minutes to settle in the inclined tube of the third reactor.

[0022] There are three reactors in total, made of PVC or fiberglass, with a volume of 0.1–10 m³. 3 The pipeline pumps are connected in series, with a flow rate of 1-10 m³ / h. 3 / h; The first reactor performs ultrasonic treatment, the second reactor simultaneously performs electrochemically enhanced heterogeneous catalytic reaction and electrocoagulation + electrocatalytic reaction, and the third reactor performs particulate electrode recovery and floc precipitation.

[0023] The wall-mounted ultrasonic transducer is made of acid and alkali resistant stainless steel or titanium, and is installed in the first reactor and connected to an ultrasonic power supply. The output frequency of the ultrasonic power supply can be adjusted from 0.1 to 200 kHz.

[0024] The stabilizing electrode and sacrificial electrode are powered by DC power supplies with an output voltage adjustment range of 0–60V; the disc aerator is made of acid and alkali resistant materials such as rubber, PP, or ABS nylon, with a working airflow of 0.05–0.2 m³ / s. 3 / h·unit, serving area 0.2~0.5m² 2 / each; the injection tube is made of PVC or PBDE material, with a diameter of 25-50mm.

[0025] The inclined tube packing is made of materials such as PP, PVC, fiberglass, or ethylene-propylene copolymer, with a tube diameter of 30–80 mm; the electromagnet is an insulated structure, waterproof and acid / alkali resistant, with an initial suction force of 1000–8000 N; the mud pump is self-priming, with a flow rate of 1–5 m³ / h. 3 / h.

[0026] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0027] (1) This application can be used for the pretreatment of antibiotic production wastewater with high suspended solids content. It can realize the desorption of antibiotics in suspended solids and their deep mineralization degradation, reduce antibiotic residues in flocs and achieve detoxification of wastewater, significantly improve the biodegradability of wastewater, improve the overall treatment efficiency of wastewater and avoid the induction of ARBs and ARGs.

[0028] (2) The device of this application has low manufacturing cost, and all supporting equipment, components and materials can be obtained through market procurement or simple customization. The device has low operating energy consumption, the method has low usage cost, and the effective detoxification and improved biodegradability of wastewater can significantly reduce the overall wastewater treatment time and cost.

[0029] (3) The electrochemical system of this application can realize the staged occurrence of electro-enhanced heterogeneous catalytic oxidation and electrocoagulation + electrocatalytic reaction based on a set of electrode reaction system, which significantly improves the space utilization of the device and saves construction costs. The columnar electrode avoids concentration polarization and electrochemical polarization and the resulting power loss. The electrode installation spacing is large, which is convenient for cleaning and maintenance.

[0030] (4) The method provided in this application is not affected by the pH, COD content and conductivity of wastewater, and is applicable to a wider range of water quality. Furthermore, the particulate electrode can be recovered by magnetic adsorption and can be reused after calcination and reactivation. Attached Figure Description

[0031] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. In the drawings:

[0032] Figure 1 This is a schematic diagram of the ultrasonic-coupled electrochemical pretreatment device for high-concentration antibiotic production wastewater provided in an embodiment of the present invention; in the figure: 1-first reactor, 2-wall hanging, 3-ultrasonic vibrating plate, 4-pipeline pump, 5-sacrificial electrode, 6-stabilizing electrode, 7-disc aerator, 8-injection pipe, 9-overflow trough, 10-inclined tube packing, 11-electromagnet, 12-toothed drainage trough, 13-outlet, 14-sludge discharge outlet, 15-sludge pump;

[0033] Figure 2 This is a schematic diagram illustrating the principle of the ultrasonic-coupled electrochemical pretreatment method for high-concentration antibiotic production wastewater provided in an embodiment of the present invention.

[0034] Figure 3 The ultrasonic-coupled electrochemical pretreatment device provided in this embodiment of the invention is effective in treating actual penicillin production wastewater.

[0035] Figure 4 The ultrasonic-coupled electrochemical pretreatment device provided in this embodiment of the invention is effective in treating erythromycin production wastewater in practice.

[0036] Figure 5 The ultrasonic-coupled electrochemical pretreatment device provided in this embodiment of the invention is shown to be effective in treating actual streptomycin production wastewater.

[0037] Figure 6 The ultrasonic-coupled electrochemical pretreatment device provided in this embodiment of the invention is shown to be effective in treating norfloxacin production wastewater. Detailed Implementation

[0038] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0039] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, with respect to numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Every smaller range between any stated value or intermediate value within a stated range, and any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0040] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.

[0041] Various modifications and variations can be made to the specific embodiments described in this specification without departing from the scope or spirit of the invention, as will be apparent to those skilled in the art. Other embodiments derived from this specification will also be obvious to those skilled in the art. This application specification and embodiments are merely exemplary.

[0042] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.

[0043] The treatment method of this invention effectively breaks the adsorption of antibiotics by suspended solids, and simultaneously achieves efficient mineralization and degradation of desorbed antibiotics and efficient flocculation of suspended solids through a low-cost electrochemical reaction system. This not only reduces antibiotic residues in flocs and detoxifies wastewater during pretreatment, but also significantly improves the biodegradability of wastewater, increases the overall treatment efficiency of wastewater, and avoids the induction of ARBs and ARGs.

[0044] The equipment, materials and reagents used in the following embodiments of the present invention are all commercially available.

[0045] In the following embodiments of the present invention, the nanocatalysts (Co3O4, CoFe2O4, MnFe2O4, CoNiFe2O4, CoZnFe2O4) and oxidants (PMS, PDS, H2O2, PAA) are all commercially available products.

[0046] The following embodiments are further illustrations of the technical solution of the present invention.

[0047] Example 1

[0048] An ultrasonic-coupled electrochemical pretreatment device for high-concentration antibiotic production wastewater consists of an ultrasonic treatment reactor, an electrochemical reactor, and a flocculation sedimentation reactor connected in series via pipelines. The first reactor is equipped with a wall-mounted ultrasonic transducer, the second reactor has a stabilizing electrode and a sacrificial electrode, and multiple disc aerators are installed at the bottom. The third reactor is equipped with an overflow trough, inclined tube packing, and an electromagnet.

[0049] The three reactors are connected in series via pipelines, which are equipped with pipeline pumps.

[0050] The second reactor is equipped with stabilizing electrodes and sacrificial electrodes arranged in an alternating symmetrical pattern, with a spacing of 6 to 30 cm between adjacent electrodes; and a liquid injection pipe is provided along one side wall of the reactor.

[0051] The third reactor is divided into an overflow trough and a sedimentation tank by a baffle plate. The overflow trough is located on one side of the third reactor adjacent to the second reactor, and the pipeline connected to the second reactor is connected through the bottom of the overflow trough. The bottom of the sedimentation tank is provided with a sludge discharge port and is connected to a sludge pump through a pipeline. The sedimentation tank is provided with a wall-mounted electromagnet and inclined tube packing that is supported and fixed by a bracket. At the same time, a toothed drainage trough is provided above the inclined tube packing, which is fixed to the side wall of the reactor by bolts and connected to the outlet located at the top of the third reactor.

[0052] Treatment method: Wastewater enters the first reactor for ultrasonic treatment; then it enters the second reactor, where granular electrodes and oxidants are added. First, an electro-enhanced heterogeneous catalytic oxidation reaction is carried out using a stable electrode as the anode and a sacrificial electrode as the cathode. Then, the electrode polarity is switched to perform electrocoagulation and electrocatalytic reactions. Finally, the wastewater enters the third reactor, where the granular electrodes are recovered by magnetic adsorption. Suspended solids are settled by inclined tube sedimentation and then pumped out by a mud pump for further treatment. The effluent enters the subsequent biological treatment stage. This invention can achieve efficient desorption and mineralization degradation of adsorbed antibiotics in suspended solids in production wastewater, reduce the residue of antibiotics and their degradation products in flocs, and eliminate the toxic effects on subsequent biological treatment stages.

[0053] Furthermore, the wastewater enters the first reactor for ultrasonic treatment; then it enters the second reactor, where granular electrodes and oxidants are added. First, an electro-enhanced heterogeneous catalytic oxidation reaction is carried out with a stable electrode as the anode and a sacrificial electrode as the cathode. Then, the electrode polarity is switched to carry out electrocoagulation and electrocatalytic reactions with a stable electrode as the cathode and a sacrificial electrode as the anode. After electrochemical treatment, the wastewater enters the bottom of the overflow tank of the third reactor. The granular electrodes are recovered by magnetic adsorption. The suspended solids are discharged by a mud pump after sedimentation in an inclined tube for further treatment. The clarified wastewater is collected by a toothed drainage trough and discharged into a sedimentation tank for further treatment.

[0054] Example 2

[0055] The ultrasonic-coupled electrochemical pretreatment device for high-concentration antibiotic production wastewater should be constructed as described above. See details below. Figure 1 The device has three reactors, all made of fiberglass. The first reactor performs ultrasonic treatment, while the second reactor simultaneously performs electrochemically enhanced heterogeneous catalytic reaction and electrocoagulation + electrocatalytic reaction. The first and second reactors are the same size (1.5 m³ / s). 3 (Length 1.5m * Width 1m * Height 1m), Third reactor (volume 2.5m³) 3 Perform particulate electrode recovery and floc precipitation.

[0056] Other components include pipeline pumps (flow rate 1-10 m³ / h). 3 / h), ultrasonic power supply (output frequency adjustment range 0.1~200kHz), wall-mounted ultrasonic transducer (titanium material, 1m long * 0.5m wide), DC power supply (constant voltage output, 0~60V adjustable), columnar titanium electrode (diameter 30mm, length 0.8m), columnar iron electrode (diameter 30mm, length 0.8m), ABS nylon disc aerator (0.1m 3 / h·piece), PVC injection pipe (diameter 32mm), PVC inclined tube packing (diameter 50mm), electromagnet (initial suction force 4000N), self-priming mud pump (flow rate 1m³ / ...). 3 ( / h) etc.

[0057] An ultrasonic-coupled electrochemical pretreatment method for high-concentration antibiotic production wastewater includes the following steps: The wastewater enters a first reactor for ultrasonic treatment for 60 minutes; the ultrasonically treated wastewater then enters a second reactor, where 5 g / L cobalt ferrite (CoFe2O4) granular electrodes and 25 g / L persulfate (PMS) oxidant are added; an electro-enhanced heterogeneous catalytic oxidation reaction is carried out using a titanium electrode as the anode and an iron electrode as the cathode for 120 minutes; the electrode polarity is switched, and an electrocoagulation + electrocatalytic reaction is carried out using a titanium electrode as the cathode and an iron electrode as the anode for 90 minutes; the electrochemically treated wastewater enters the overflow tank of a third reactor, where the granular electrodes are recovered by magnetic adsorption, and the wastewater settles for 120 minutes. The principle of the ultrasonic-coupled electrochemical pretreatment method is described in [link to relevant documentation]. Figure 2 .

[0058] High performance liquid chromatography (Shimadzu LC-20AT) was used to determine penicillin, erythromycin, streptomycin and norfloxacin. An Agilent ZORBAX SB Aq (4.6×250mm, 5μm) column was used and the column temperature was 35℃. For penicillin testing, the mobile phase was 0.1% formic acid and acetonitrile (35:65, v:v), the flow rate was 0.8 mL / min, the injection volume was 20 μL, and the detection wavelength was 210 nm. For erythromycin testing, the mobile phase was dipotassium hydrogen phosphate (0.03 mol / L, pH=10) and acetonitrile (45:55, v:v), the flow rate was 1 mL / min, the injection volume was 20 μL, and the detection wavelength was 215 nm. For streptomycin testing, the mobile phase was 0.05% phosphoric acid and acetonitrile (72:28, v:v), the flow rate was 1 mL / min, the injection volume was 20 μL, and the detection wavelength was 278 nm. For norfloxacin testing, the mobile phase was 0.1% formic acid and methanol (40:60, v:v), the flow rate was 1 mL / min, the injection volume was 20 μL, and the detection wavelength was 286 nm.

[0059] Wastewater from penicillin production at a pharmaceutical company was used as a representative of wastewater from the production process of β-lactam antibiotics for treatment. The physicochemical properties of the wastewater are detailed in Table 1.

[0060] Table 1 Physicochemical properties of actual penicillin production wastewater

[0061]

[0062] The results show that ( Figure 3 With prolonged ultrasonic treatment, the adsorbed penicillin in the suspended solids gradually desorbed, and the concentration of penicillin in the wastewater increased from the initial 11.3 mg / L to 14.2 mg / L. Electro-enhanced heterogeneous catalytic oxidation and electrocoagulation + electrocatalytic reaction can effectively remove COD. Cr(Residual concentration 1411 mg / L, removal rate 91.3%), BOD5 (residual concentration 757 mg / L, removal rate 85.4%), NH3-N (residual concentration 57 mg / L, removal rate 71.6%), SS (residual concentration 320 mg / L, removal rate 96.3%), penicillin removal efficiency reached 100%, wastewater biodegradability was significantly improved, BOD5 / COD ratio Cr The value increased from the initial 0.32 to 0.54.

[0063] Example 3

[0064] The ultrasonic-coupled electrochemical pretreatment device is the same as in Example 1. The wastewater from the production of erythromycin in a real pharmaceutical company is used as a representative of the wastewater from the production process of macrolide antibiotics for treatment. The physicochemical properties of the wastewater are detailed in Table 2.

[0065] Table 2 Physicochemical properties of actual erythromycin production wastewater

[0066]

[0067] The results show that ( Figure 4 As the ultrasonic treatment time increased, the adsorbed erythromycin in the suspended solids gradually desorbed and entered the wastewater, with the concentration increasing from the initial 1.3 mg / L to 2.2 mg / L. Electro-enhanced heterogeneous catalytic oxidation and electrocoagulation + electrocatalytic reaction can effectively remove COD. Cr (Residual concentration 372 mg / L, removal rate 95.7%), BOD5 (residual concentration 213 mg / L, removal rate 91.5%), NH3-N (residual concentration 14 mg / L, removal rate 82.3%), SS (residual concentration 21 mg / L, removal rate 98.7%), and erythromycin removal efficiency reached 100%, significantly improving the biodegradability of wastewater, and the BOD5 / COD ratio... Cr The value increased from the initial 0.29 to 0.57.

[0068] Example 4

[0069] The ultrasonic-coupled electrochemical pretreatment device is the same as in Example 1. The wastewater from streptomycin production in a real pharmaceutical company is used as a representative of the wastewater from the production process of aminoglycoside antibiotics for treatment. The physicochemical properties of the wastewater are detailed in Table 3.

[0070] Table 3 Physicochemical properties of actual streptomycin production wastewater

[0071]

[0072] The results show that ( Figure 5With prolonged ultrasonic treatment, the adsorbed streptomycin in the suspended solids gradually desorbed and entered the wastewater, increasing the concentration from the initial 17.6 mg / L to 19.4 mg / L. Electro-enhanced heterogeneous catalytic oxidation and electrocoagulation + electrocatalytic reaction can effectively remove COD. Cr (Residual concentration 641 mg / L, removal rate 94.5%), BOD5 (residual concentration 324 mg / L, removal rate 90.9%), NH3-N (residual concentration 26 mg / L, removal rate 79.2%), SS (residual concentration 51 mg / L, removal rate 98.0%), and erythromycin removal efficiency reached 100%, significantly improving the biodegradability of wastewater and the BOD5 / COD ratio. Cr The value increased from the initial 0.31 to 0.51.

[0073] Example 5

[0074] The ultrasonic-coupled electrochemical pretreatment device is the same as in Example 1. The wastewater from the production of norfloxacin in a real pharmaceutical company is used as a representative of the wastewater from the production process of quinolone antibiotics for treatment. The physicochemical properties of the wastewater are detailed in Table 4.

[0075] Table 4 Physicochemical Properties of Actual Norfloxacin Production Wastewater

[0076]

[0077] The results show that ( Figure 6 With prolonged ultrasonic treatment time, the adsorbed norfloxacin in the suspended solids gradually desorbed and entered the wastewater, increasing the concentration from the initial 5.7 mg / L to 8.4 mg / L. Electro-enhanced heterogeneous catalytic oxidation and electrocoagulation + electrocatalytic reaction can effectively remove COD. Cr (Residual concentration 721 mg / L, removal rate 94.9%), BOD5 (residual concentration 417 mg / L, removal rate 84.6%), NH3-N (residual concentration 16 mg / L, removal rate 76.8%), SS (residual concentration 37 mg / L, removal rate 97.2%), and erythromycin removal efficiency reached 100%, significantly improving the biodegradability of wastewater, and the BOD5 / COD ratio... Cr The value increased from the initial 0.19 to 0.58.

[0078] Example 6

[0079] The ultrasonic-coupled electrochemical pretreatment device is the same as in Example 1, except that the wastewater does not enter the first reactor for ultrasonic treatment. Instead, electrochemically enhanced heterogeneous catalytic reaction and electrocoagulation + electrocatalytic reaction are performed only in the second reactor, and particulate electrode recovery and floc sedimentation are performed in the third reactor. The residual levels of penicillin, erythromycin, streptomycin, and norfloxacin in the wastewater and precipitated sludge are detailed in Table 5. Compared with wastewater without ultrasonic treatment, ultrasonic treatment can avoid antibiotic residues in the sludge and promote the electrocatalytic degradation of antibiotics.

[0080] Table 5. Antibiotic residues in sludge and treated effluent under different treatment conditions.

[0081]

Claims

1. A method for ultrasonic-coupled electrochemical pretreatment of high-concentration antibiotic production wastewater, comprising an ultrasonic-coupled electrochemical pretreatment device for high-concentration antibiotic production wastewater, characterized in that: The device consists of an ultrasonic treatment reactor, an electrochemical reactor, and a flocculation sedimentation reactor connected in series via pipelines. The first reactor is equipped with a wall-mounted ultrasonic transducer, the second reactor has a stabilizing electrode and a sacrificial electrode and multiple disc aerators at the bottom, and the third reactor has an overflow trough, inclined tube packing and an electromagnet. The second reactor is equipped with stabilizing electrodes and sacrificial electrodes arranged in an alternating symmetrical pattern, with a spacing of 6-30 cm between adjacent electrodes; and a liquid injection pipe is provided along one side wall of the reactor. The device utilizes ultrasonic water oxidation and mechanical shearing to desorb antibiotics adsorbed in wastewater suspension. Then, the wastewater passes through electrodes, and the switching of electrodes achieves stages of electro-enhanced heterogeneous catalytic oxidation, electrocoagulation, and electrocatalytic reactions, thereby achieving deep mineralization and degradation of high-concentration antibiotics in wastewater, reducing the residue of antibiotics and their degradation products in the flocs, and eliminating the toxicity of the wastewater. Wastewater enters the first reactor for ultrasonic treatment; then it enters the second reactor, where granular electrodes and oxidants are added. Initially, an electro-enhanced heterogeneous catalytic oxidation reaction is carried out with a stable electrode as the anode and a sacrificial electrode as the cathode. Then, the electrode polarity is switched to use a stable electrode as the cathode and a sacrificial electrode as the anode for electrocoagulation and electrocatalytic reactions. After electrochemical treatment, the wastewater enters the bottom of the overflow tank of the third reactor. The granular electrodes are recovered by magnetic adsorption. Suspended solids are discharged by a mud pump after sedimentation in inclined tubes for further treatment. The clarified wastewater is collected in a toothed drainage trough and discharged into a sedimentation tank for further treatment. The stabilizing electrode is selected from graphite, titanium, titanium alloy, or boron-doped diamond; the sacrificial electrode is selected from iron, aluminum, or their alloys; the working airflow of the disc aerator is 0.05-0.2 m³ / s. 3 / h·unit, serving area 0.2-0.5m² 2 / indivual; The ultrasonic treatment time for the first reactor is 10-120 min; The particulate electrode in the second reactor is selected from one or more of cobalt tetroxide (Co3O4), cobalt ferrite (CoFe2O4), manganese ferrite (MnFe2O4), nickel cobalt ferrite (CoNiFe2O4), and zinc cobalt ferrite (CoZnFe2O4); the dosage of the particulate electrode is 0.1-10 g / L; the oxidant is selected from one or more of persulfate (PMS), perdisulfate (PDS), hydrogen peroxide (H2O2), and peracetic acid (PAA); the dosage of the oxidant is 0.5-50 g / L.

2. The ultrasonic-coupled electrochemical pretreatment method for high-concentration antibiotic production wastewater according to claim 1, characterized in that, The three reactors are connected in series via pipelines, which are equipped with pipeline pumps.

3. The ultrasonic-coupled electrochemical pretreatment method for high-concentration antibiotic production wastewater according to claim 1, characterized in that, The third reactor is divided into an overflow trough and a sedimentation tank by a baffle plate. The overflow trough is located on one side of the third reactor adjacent to the second reactor, and the pipeline connected to the second reactor is connected through the bottom of the overflow trough. The bottom of the sedimentation tank is provided with a sludge discharge port and is connected to a sludge pump through a pipeline. The sedimentation tank is provided with a wall-mounted electromagnet and inclined tube packing that is supported and fixed by a bracket. At the same time, a toothed drainage trough is provided above the inclined tube packing, which is fixed to the side wall of the reactor by bolts and connected to the outlet located at the top of the third reactor.

4. The ultrasonic-coupled electrochemical pretreatment method for high-concentration antibiotic production wastewater according to claim 1, characterized in that: In the second reactor, an electro-enhanced heterogeneous catalytic oxidation reaction is carried out for 15-180 min with a stable electrode as the anode and a sacrificial electrode as the cathode; then, the electrode polarity is switched to carry out electrocoagulation and electrocatalytic reactions for 15-180 min.

5. The ultrasonic-coupled electrochemical pretreatment method for high-concentration antibiotic production wastewater according to claim 1, characterized in that: The wastewater takes 60-240 minutes to settle in the inclined tube of the third reactor.

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