Resource treatment method for antibiotic pharmaceutical waste liquid

Abstract

The present invention discloses a method for resource-based treatment of antibiotic pharmaceutical wastewater, belonging to the technical field of pharmaceutical wastewater treatment. The method comprises: S10: sequentially acidifying and pre-oxidizing the antibiotic fermentation wastewater; S20: adding a composite precipitant to the wastewater, stirring the reaction, and then allowing the mixture to settle, separating the supernatant and the precipitate; S30: adjusting the pH of the supernatant and performing an adsorption treatment; S35: performing solid-liquid separation on the wastewater; S40: adding a copper-iron composite oxide to the wastewater for reaction and separating the flocculated sludge; S50: removing calcium ions from the wastewater through chelation, and performing a pulsed electric field crystallization suppression treatment and vacuum evaporation concentration to obtain a concentrated solution; S55: desalting the concentrated solution through nanofiltration; and S60: using the concentrated solution to prepare organic fertilizer or chemical raw materials. The present invention solves the problems of low COD removal rate, antibiotic inhibition of microbial activity, and resource waste in traditional methods, providing a reliable technical path for efficient resource-based treatment of antibiotic pharmaceutical wastewater.

Description

Technical Field

[0001] The present invention relates to the technical field of pharmaceutical waste liquid treatment, and in particular to a resource treatment method for antibiotic pharmaceutical waste liquid. Background Art

[0002] Antibiotic pharmaceutical wastewater, a high-concentration organic wastewater generated during the production process, often has a chemical oxygen demand (COD) as high as 50,000 mg / L, indicating that it contains a large amount of undecomposed organic matter. According to relevant research, COD concentrations in antibiotic wastewater generally range from 10,000 to 80,000 mg / L, and TDS (total dissolved solids) fluctuate from 10,000 to 80,000 mg / L (cephalosporin wastewater can exceed 100,000 mg / L). The presence of biotoxic substances such as residual antibiotics, high concentrations of sulfate, high concentrations of acids and bases, and organic solvents makes treatment complex and costly. Furthermore, the presence of high concentrations of residual antibiotics in the wastewater—for example, penicillin concentrations are typically 200 to 500 mg / L—can inhibit wastewater treatment systems. The wastewater may also contain other potential pollutants such as heavy metals and organic solvents. If such waste liquid is discharged directly into water bodies or soil without proper treatment, it will not only induce eutrophication of water bodies, destroy the ecosystem and cause serious environmental pollution, but may also trigger an antibiotic resistance crisis through the spread of microbial resistance genes, posing a serious threat to human and animal health.

[0003] Traditional physicochemical and biochemical treatment methods have significant limitations in treating antibiotic pharmaceutical wastewater:

[0004] 1. Biochemical process (such as activated sludge process):

[0005] The COD removal rate is usually less than 80%, mainly because residual antibiotics have a strong inhibitory effect on microbial activity, which greatly reduces the biodegradation efficiency. In addition, long-term operation is prone to cause sludge swelling or the risk of total system collapse.

[0006] 2. Conventional physicochemical process (such as Fenton oxidation):

[0007] Although it can partially degrade antibiotics, it has problems such as large iron sludge production (accounting for 15% to 20% of the waste liquid volume), difficulty in recovering the catalyst, and high operating costs;

[0008] 3. Resource recovery technology:

[0009] Conventional evaporation and concentration processes cause a loss of ≥35% of heat-sensitive nutrients such as organic acids and amino acids due to high temperatures, and are unable to simultaneously resolve the contradiction between excessive antibiotic residues and salt levels (TDS>60,000 mg / L) in the concentrate. Chemical scale inhibitors have low inhibition efficiency on CaSO4 (crystal nucleus size>200 nm) and introduce new pollutants.

[0010] Therefore, existing technologies for treating antibiotic pharmaceutical wastewater have the following deficiencies: First, they have a significant weakness in their ability to deeply degrade high-concentration organic matter and residual antibiotics, making biochemical treatments susceptible to limitations and physicochemical treatments inefficient. Second, the lack of an efficient resource recovery mechanism makes it difficult to effectively recycle high-value-added components in the wastewater. Furthermore, there is a significant risk of secondary pollution, manifested in the difficulty of disposing of iron sludge and the problem of salt and antibiotic residues in the concentrate. Summary of the Invention

[0011] The present invention provides a method for resource-based treatment of antibiotic pharmaceutical wastewater, aiming to solve the degradation problem of high-concentration organic matter and residual antibiotics in antibiotic fermentation wastewater through the chain parameter coupling design of multi-stage chemical and physicochemical treatment processes, and simultaneously achieve a closed loop of wastewater purification and resource recovery.

[0012] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0013] The method for resource-based treatment of antibiotic pharmaceutical waste liquid comprises the following steps:

[0014] S10: acidifying and pre-oxidizing the antibiotic fermentation wastewater in sequence;

[0015] S20: adding a composite precipitant to the waste liquid treated in S10, stirring the mixture, and then allowing the mixture to settle, and separating the supernatant and the precipitate;

[0016] S30: adjusting the pH of the supernatant obtained in S20 to 8-9 and performing adsorption treatment;

[0017] S35: performing solid-liquid separation on the waste liquid treated in S30;

[0018] S40: Add 0.5% to 1.0% of the mass of the original waste liquid to the waste liquid treated in S35, control the oxygen partial pressure to 0.8 to 1.2 MPa, and react at 160 to 180°C for 45 to 75 minutes; after the reaction, cool to 60 to 70°C, add 0.1% to 0.3% of the mass of the original waste liquid, stir at 50 to 60°C for 20 to 30 minutes, adjust the pH to 7.5 to 8.5 to generate Fe(OH)3 colloid, and let it stand to separate the flocculated sludge;

[0019] S50: The waste liquid treated in S40 is subjected to chelation to remove calcium ions, and is subjected to pulse electric field suppression crystallization treatment and vacuum evaporation concentration to reduce the volume of the waste liquid to 1 / 5 to 1 / 3 of the original waste liquid to obtain a concentrated solution;

[0020] S55: The concentrate is desalted by nanofiltration at an operating pressure of 1.5-2.5 MPa;

[0021] S60: Detect antibiotic residues, heavy metal content and salt concentration of nanofiltration permeate in the concentrate, add synergists according to the type of antibiotics, and then use the concentrate to prepare organic fertilizers or chemical raw materials.

[0022] Specifically, in S10, the antibiotic fermentation waste liquid is acidified and the pH is adjusted to 3.0-3.8, and then hydrogen peroxide is added for pre-oxidation reaction. The amount of hydrogen peroxide added is 0.7%-0.9% of the mass of the original waste liquid, the reaction temperature is 45-55°C, and the reaction time is 40-50 minutes.

[0023] Specifically, the composite precipitant in S20 is a mixture of ferrous sulfate and calcium hydroxide in a mass ratio of 1:2.5, and the addition amount is 2% to 5% of the mass of the original waste liquid. The stirring reaction is carried out for 30 to 60 minutes, and the stirring speed is 120 to 180 revolutions per minute.

[0024] Specifically, activated carbon is used for adsorption treatment in S30; the mesh size of the activated carbon powder is 50-100 meshes, the dosage is 2%-3% of the mass of the original waste liquid, and the adsorption time is 90-120 minutes.

[0025] Preferably, in S35, the activated carbon is recovered and regenerated by a thermal regeneration method and then reused in S30.

[0026] Preferably, the dosage of copper-iron composite oxide in S40 is 0.7% to 0.9% of the mass of the original waste liquid, the reaction temperature is 170 to 175° C., and the oxygen partial pressure is 1.0 to 1.1 MPa.

[0027] Preferably, the amount of hydrogen peroxide added in S40 is 0.15% to 0.25% of the mass of the original waste liquid, and the pH is adjusted to 8.0 to 8.2.

[0028] Specifically, S50 includes the following steps:

[0029] S501: The wastewater treated in S40 is passed through a two-stage chelating resin bed to remove more than 95% of calcium ions, and then introduced into a conductivity adjustment tank and diluted with pure water to a conductivity of ≤500μS / cm;

[0030] S502: The diluted liquid is pumped into a pulse electric field reactor and treated under nitrogen protection for 10 to 15 minutes, and 0.5 to 1.0 ppm ATMP scale inhibitor is simultaneously added. The parameters of the pulse electric field reactor are: electrode spacing 8.0 to 12.0 cm, field strength 1.5 to 2.5 kV / cm, frequency 1 to 3 kHz, and pulse width 10 to 20 μs.

[0031] S503: The treated waste liquid is immediately pumped into a falling film evaporator and concentrated to 1 / 5 to 1 / 3 of the original waste liquid volume at an operating temperature of 55 to 58°C and a pressure of -0.085 to -0.095 MPa; the flow rate of the falling film evaporator is 1.8 to 2.5 m / s.

[0032] Furthermore, the present invention also includes S55a: removing volatile organic matter from the evaporated condensate produced in S50 by adsorbing activated carbon; the adsorption-saturated activated carbon is introduced into S35 to regenerate the activated carbon and then reused in S50.

[0033] Preferably, in S60, when the antibiotic residue is less than 0.15 mg / L, the heavy metal content satisfies Cu≤50 mg / kg, Zn≤200 mg / kg, and the permeate TDS≤10000 mg / L, a synergist is added according to the type of antibiotic; the synergist is papain or Bacillus subtilis.

[0034] Compared with the prior art, the present invention has the following beneficial effects:

[0035] (1) In step S10, by acidification and introduction of hydrogen peroxide (as an oxidant), in an acidic environment with a pH of 3.0 to 3.8, the + Protonation promotes the β－ lactams) by hydrolysis (e.g. β－ Lactams), relieving their inhibitory effects on microbial activity; simultaneously, hydrogen peroxide decomposes under acidic conditions to produce hydroxyl radicals (•OH), which further oxidize and decompose residual antibiotics and macromolecular organic matter (mass molecular weight distribution >500 Da) into small molecular fragments (mass molecular weight distribution <500 Da), thereby reducing the wastewater's potential inhibitory properties. In the present invention, the hydrogen peroxide dosage is 0.7% to 0.9% of the original wastewater mass, the temperature is 45-55°C, and the reaction time is 40-50 minutes. This parameter combination significantly improves the subsequent catalytic oxidation efficiency (for example, in Table 1 below, the antibiotic residue in Example 1 is undetectable, while in Comparative Example 1, the unoxidized residue is 0.25 mg / L; the data in Table 6 shows that pre-oxidation shortens the catalytic oxidation reaction time by 40%), creating efficient reaction conditions for subsequent catalytic wet oxidation.

[0036] (2) In step S20, a composite precipitant is added to the waste liquid treated in step S10. The introduction of the composite precipitant solves the problem of removing suspended particles and some refractory organic matter in the waste liquid, and achieves efficient solid-liquid separation. The composite precipitant is made of ferrous sulfate and calcium hydroxide in a mass ratio of 1:2.5, which forms nano-flocculation with a porosity of 65±5%. The mechanism is as follows: ferrous sulfate (FeSO4) provides Fe 2+ , and heavy metal ions (such as Cu 2+ 、Zn 2+) forms a stable complex; calcium hydroxide (Ca(OH)2) adjusts the pH to alkaline (pH 8-9) to promote the formation of CaSO4 crystal nuclei. The two work together to form dense flocs, thereby accelerating the precipitation of suspended matter and heavy metals. Experimental data show that when the mass ratio is 1:2.5, the heavy metal removal rate is significantly increased to 98.5% (Cu 2+ ) and 99.0% (Zn 2+ ), while the volume fraction of sediment dropped to 6.5%. The parameter combination of a composite precipitant dosage of 2% to 5% and a stirring speed of 120 to 180 rpm reduces sludge production while ensuring sedimentation efficiency. Therefore, steps S10 and S20 form a synergistic treatment chain: acidification pre-oxidation hydrolyzes macromolecular organic matter into small molecular fragments, creating favorable conditions for subsequent precipitation reactions; the composite precipitant forms high-porosity flocs under optimized ratios, efficiently removing heavy metals, reducing sediment, and achieving deep purification. At the same time, the present invention converts heavy metals into a stable residual state (effective state proportion <15%) through chemical complexation-coprecipitation, eliminating the need for a biological conversion process.

[0037] (3) In step S30, the activated carbon powder with a mesh size of 50 to 100 can provide a high adsorption surface area. Combined with the design of a dosage of 2% to 3% and an adsorption time of 90 to 120 minutes, it can fully remove trace residual antibiotics.

[0038] (4) Based on steps S10–S30, in step S40, organic matter is directly mineralized by catalytic wet oxidation under high temperature and high pressure, and CuO activates O2 to produce ·OH radicals to completely degrade residual antibiotics (such as β－ Lactam ring cleavage rate>99.9%); in this stage, antibiotics and their inhibitory intermediates (mass molecular weight distribution>500Da, component removal rate>95%) are preferentially degraded to eliminate biological toxicity; the remaining small molecular organic matter (mass molecular weight distribution<500Da) is gradually mineralized through free radical chain reaction. Subsequent iron flocculation utilizes the in situ generated Fe 3+ The colloid captures trace heavy metals (Cu / Zn removal rates >97%) and immobilizes them through co-precipitation, reducing their effective content to less than 15%, meeting the requirements of NY / T 525-2021. The resulting heavy metal-containing flocculent sludge can be smelted to recover metals, realizing the resource utilization of hazardous waste.

[0039] (5) In step S50, in order to solve the problem that the conventional evaporation concentration process causes the loss of organic nutrients to be greater than 35% due to high temperature and cannot simultaneously solve the contradiction between the residual antibiotics in the concentrate and the excessive salt content, the present invention designs a four-stage coupling process of "chelation decalcification-conductivity dilution-pulse electric field crystal suppression-low temperature vacuum evaporation", which is specifically as follows: 1) Chelation decalcification pretreatment: the wastewater flows through a two-stage chelating resin bed, and the resin functional groups react with Ca 2+Specific complexation removes >95% of calcium ions, avoiding CaSO4 scaling at the source; 2) Conductivity optimization: dilute the wastewater conductivity to ≤500μS / cm with pure water to ensure safe pulsed electric field operation; 3) Pulsed electric field crystallization inhibition: apply a 1-3kHz alternating electric field (field strength 1.5-2.5kV / cm, pulse width 10-20μs, and treat under nitrogen protection for 10-15 minutes), and simultaneously add 0.5-1.0ppm ATMP scale inhibitor to enhance the scale inhibition effect. Use wide pulse disturbance to make the Zeta potential of the CaSO4 crystal nucleus surface oscillate by more than ±10mV, destroy the orderly arrangement of ions, and suppress the crystal nucleus size to <50nm; 4) Low-temperature vacuum evaporation: use a falling film evaporator (flow rate 1.8-2.5 m / s) at 55-58°C and -0.085-0.095 MPa, achieving efficient retention of heat-sensitive organic components (organic acid retention rate >97%, amino acid retention rate >95.8%, an absolute increase of more than 36% compared to conventional evaporation at 80°C); 5) reducing the volume of wastewater to 1 / 3-1 / 5 of the original solution (concentration factor 3-5 times), controlling the TDS of the concentrate to 35,000-42,000 mg / L (only 60% of the TDS of conventional evaporation), and reducing energy consumption by 40%.

[0040] In addition, in step S55, the concentrate is desalted by a nanofiltration membrane, and the permeate is collected as a salt detection benchmark. The membrane pore size (0.5-1 nm) is used to selectively retain organic matter and small molecular salts: the desalination rate is >70%, and the permeate TDS is ≤10000 mg / L.

[0041] In this way, through the combination of pulsed electric field crystal suppression technology and composite precipitants, not only the defects of traditional scale inhibitors are avoided from the source, but also the problem of high salinity limiting resource utilization is effectively solved, ensuring that the concentrated liquid can be directly used for the preparation of organic fertilizers or chemical raw materials.

[0042] (6) In step S60, the antibiotic residue and heavy metal content in the concentrated liquid are tested to ensure that the final product meets the relevant standard requirements. Specifically, when the antibiotic residue is less than 0.15 mg / L, the heavy metal content meets the requirements of Cu ≤ 50 mg / kg, Zn ≤ 200 mg / kg, and the permeate TDS ≤ 10,000 mg / L, a targeted synergist is added according to the type of antibiotic (e.g., 0.1% papain is added for penicillins, and Bacillus subtilis is loaded for macrolides). The concentrated liquid is used to prepare organic fertilizers or chemical raw materials, thereby achieving the goal of waste liquid resource utilization and avoiding environmental pollution.

[0043] (7) The present invention improves the COD removal rate through "pre-oxidation-catalytic oxidation", combines the resource closed-loop design (activated carbon regeneration, concentrated liquid fertilizer) and the iron valence state migration cycle, solves the contradiction between deep purification of highly toxic waste liquid and resource recovery, and provides an efficient physical and chemical technology path for the treatment of antibiotic pharmaceutical waste liquid. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 It is a schematic flow diagram of the present invention. DETAILED DESCRIPTION

[0045] The present invention provides a method for resource-based treatment of antibiotic pharmaceutical wastewater, which effectively removes harmful substances in the wastewater and recycles resources through multi-stage treatment. Specifically, the present invention solves the contradiction between purification and resource recovery, mainly including: 1) adding hydrogen peroxide in an acidified environment to make β－ The lactam ring breaks, and at the same time, OH radicals oxidize and decompose macromolecular organic matter; 2) Catalytic oxidation-evaporation cycle: During catalytic wet oxidation, Fe 3+ , in iron flocculation, Fe 3+ The evaporation and concentration stage uses low-temperature vacuum combined with pulsed electric field and ATMP scale inhibitor to inhibit salt crystallization and protect heat-sensitive nutrients, forming "iron migration － Vacuum evaporation and concentration" cycle; 3) Resource-based design: 31) After activated carbon is regenerated, it is circulated to the main adsorption section to achieve regeneration adsorption and form a closed loop; 32) Based on the type of antibiotic, the synergist is matched (such as β－ lactams and 0.1% papain were added to convert the desalted concentrate into functional fertilizer / chemical raw materials, forming a "waste liquid － Purification － Resources" system.

[0046] The steps of the present invention are described below. Figure 1 shown.

[0047] Step S10: The antibiotic fermentation wastewater is introduced into an acidification treatment unit, and an acidic reagent is added to adjust the wastewater pH to an acidic environment of 3.0 to 3.8. Hydrochloric acid or sulfuric acid can be used as the acidic reagent, with hydrochloric acid being preferred due to its strong acidity, low cost, and ability to effectively dissolve some impurities in the wastewater. After acidification, hydrogen peroxide is added to the wastewater for a pre-oxidation reaction, thereby destroying the molecular structure of the residual antibiotics. The amount of hydrogen peroxide added is 0.7% to 0.9% of the original wastewater mass. The reaction temperature is controlled between 40°C and 60°C, and the reaction time is 30 to 60 minutes. Under these conditions, the molecular structure of the residual antibiotics in the wastewater is partially destroyed, and some organic matter is converted into a more easily degradable form, laying the foundation for subsequent treatment.

[0048] Step S20: The waste liquid treated in Step S10 is introduced into a composite precipitant dosing and stirring device, where a composite precipitant is added to the waste liquid. The composite precipitant is composed of ferrous sulfate and calcium hydroxide mixed in a mass ratio of 1:2 to 1:3, and the dosage is 2% to 5% of the original waste liquid mass. The stirring speed is controlled at 120 to 180 rpm to uniformly mix the waste liquid; the stirring time is 30 to 60 minutes. After stirring, the mixture is allowed to settle for 30 to 60 minutes to allow the precipitate to fully settle. The supernatant and precipitate are then separated, and the precipitate can be subsequently treated or safely disposed of.

[0049] Step S30: The pH of the supernatant after treatment in step S20 is adjusted to 8-9 using a NaOH solution. Activated carbon powder is then added to utilize its powerful adsorption capacity to effectively remove residual organic matter and trace amounts of antibiotics from the wastewater. The activated carbon powder has a mesh size of 50-100 to ensure a high adsorption surface area. The dosage is 2%-3% of the original wastewater mass, and the adsorption time is 90-120 minutes.

[0050] Step S35: The waste liquid treated in step S30 is subjected to solid-liquid separation to recover activated carbon powder. The recovered activated carbon is regenerated through a thermal regeneration process (specifically, the drying stage involves heating to 100-150°C to remove moisture and low-boiling volatile components; the high-temperature carbonization stage involves raising the temperature to 700-750°C to form "fixed carbon"; and the activation stage involves introducing water vapor (at a flow rate of 1.5 L / min for 45 minutes) to react with the "fixed carbon," cleaning the micropores, increasing the activated carbon's specific surface area and adsorption properties, and restoring its adsorption capacity). The regenerated activated carbon is then recycled back to step S30, reducing processing costs and waste.

[0051] Step S40: Pump the waste liquid treated in step S35 into the autoclave, add 0.5% to 1.0% of the original waste liquid mass of copper-iron composite oxide (CuO / Fe2O3 complex, the preparation process is as follows: a, dissolve ferrous chloride and cupric chloride in water at a molar ratio of Cu:Fe=0.1, add a specific surface area ≥300m 2 / g, a diatomaceous earth ceramsite carrier with a particle size of 2-5mm and a pore size distribution of 5-10nm, was shaken at 180rpm for 4h in a 5L shaker to allow the metal ions to be fully adsorbed into the carrier pores; b. 0.5 mol / L sodium carbonate solution was slowly added to the carrier system loaded with metal ions, the pH was controlled at 9.0-10.0, and the reaction was stirred at 25-35℃ for 2-4h to generate a Cu-Fe carbonate / basic carbonate composite precipitate; c. The precipitate was filtered and vacuum dried at 40-60℃ for 24-48h; the dried product was placed in a muffle furnace and calcined in stages under air atmosphere: the first stage: the temperature was raised to 300℃ at 5℃ / min and kept warm for 1h; the second stage: the temperature was continued at 3℃ / min Heat to 500-650°C, keep warm for 2-4 hours to form a stable CuO / Fe2O3 crystal structure), introduce compressed air to control the oxygen partial pressure to 0.8-1.2 MPa, and react at 160-180°C for 45-75 minutes (this high temperature stage is for the mineralization of refractory organic matter);

[0052] After the reaction, the molecular weight distribution of organic matter was detected: the removal rate of components with a molecular weight distribution of >500 Da was more than 95% (initial proportion 45% → final value less than 5%), and the proportion of components with a molecular weight distribution of <500 Da increased from 55% to 92%; after the reaction, the effluent was cooled to 60-70°C through a heat exchanger, and 0.1%-0.3% of the original waste liquid mass of hydrogen peroxide was added. The mixture was stirred at 50-60°C for 20-30 minutes, and the pH was adjusted to 7.5-8.5 to generate Fe(OH)3 colloid (main mechanism: in the catalytic wet oxidation stage, the organic acid generated by the oxidation of organic matter promotes the partial dissolution of Fe2O3 in the copper-iron composite oxide to release Fe 3+ After the reaction, the temperature was lowered to 60-70°C, hydrogen peroxide was added to further oxidize the residual reduced substances and the pH was adjusted to 7.5-8.5 to make Fe 3+ Converted into Fe(OH)3 colloid to achieve flocculation), and the flocculated sludge is allowed to stand and separate.

[0053] Step S50: The waste liquid treated in step S40 is passed through a two-stage chelating resin bed (Ca 2+ Removal rate >95%), then introduced into a conductivity adjustment tank and diluted with pure water to a conductivity of ≤500 μS / cm. The diluted solution was pumped into a pulsed electric field reactor (electrode spacing 8.0-12.0 cm, field strength 1.5-2.5 kV / cm, frequency 1-3 kHz, pulse width 10-20 μs) for treatment under nitrogen for 10-15 minutes. 0.5-1.0 ppm ATMP scale inhibitor was simultaneously added. The treated wastewater was immediately pumped into a falling film evaporator at a flow rate of 1.8-2.5 m / s, a temperature of 55-58°C, and an operating pressure of -0.08 MPa to -0.095 MPa (gauge pressure). The volume was reduced to 1 / 5-1 / 3 of the original solution.

[0054] Step S55: The concentrate is desalted by nanofiltration at an operating pressure of 1.5-2.5 MPa. The permeate is collected as a salt content test standard. The desalination rate is greater than 70% (desalination rate = (1-permeate TDS / concentrate TDS) × 100%), and the permeate TDS is reduced to ≤10,000 mg / L.

[0055] Step S55a: The evaporation condensate produced in step S50 is adsorbed with activated carbon to remove volatile organic compounds, so that the TOC of the condensate is ≤15 mg / L; the adsorption-saturated activated carbon is collected in step S35 to achieve activated carbon regeneration and then reused in step S50.

[0056] Step S60: Perform TDS testing on the nanofiltration permeate, and simultaneously test the concentrated solution for antibiotic residues (using high-performance liquid chromatography to detect antibiotic residues) and heavy metal content (heavy metals include Cu and Zn, with limits of Cu≤50mg / kg and Zn≤200mg / kg, respectively) to determine the feasibility of resource recovery. When the antibiotic residue is less than 0.15mg / L, the heavy metal content satisfies Cu≤50mg / kg and Zn≤200mg / kg, and the permeate TDS is ≤10000mg / L, a targeted synergist is added based on the type of antibiotic: if penicillin residue is detected, 0.1% papain is added for hydrolysis; if macrolides are detected, 10% is added. 8 CFU / g Bacillus subtilis, and the concentrated liquid is used to prepare organic fertilizer or chemical raw materials.

[0057] The following examples are illustrative and are only used to illustrate the present invention. All reagents and instruments used without manufacturer's indication are commercially available conventional products.

[0058] Example 1

[0059] Step S10: 1000 kg of antibiotic fermentation waste liquid (initial penicillin 220 mg / L) was taken, hydrochloric acid was added to adjust the pH to 3.5, and hydrogen peroxide was added for pre-oxidation reaction. The amount of hydrogen peroxide added was 0.8% of the mass of the original waste liquid. The reaction temperature was 50°C and the reaction time was 50 minutes.

[0060] Step S20: adding a composite precipitant to the waste liquid, wherein the composite precipitant is composed of ferrous sulfate and calcium hydroxide mixed in a mass ratio of 1:2.5, and the addition amount is 3.5% of the original waste liquid mass, the stirring speed is 150 revolutions per minute, the stirring time is 45 minutes, and the supernatant and the precipitate are separated after standing and settling for 50 minutes.

[0061] Step S30: The pH of the supernatant is adjusted to 8.5, and activated carbon powder is added for adsorption treatment. The particle size of the activated carbon powder is 80 mesh, the addition amount is 2.5% of the original waste liquid mass, and the adsorption time is 95 minutes.

[0062] Step S35: Separate the waste liquid into solid and liquid, recover the activated carbon, and reuse it in step S30 after regeneration.

[0063] Step S40: The effluent from step S35 (COD of 10500 mg / L, penicillin 0.02 mg / L) was placed in a high-pressure reactor, and then 0.8% of the original wastewater mass of copper-iron composite oxide was added. Air was vented to an oxygen partial pressure of 1.0 MPa, and the reaction was carried out at 175°C for 60 minutes. The COD dropped to 980 mg / L; the molecular weight distribution changed: the component >500 Da dropped from 45% to 3.2%, and the component <500 Da increased from 55% to 96.8%. The temperature was then lowered to 65°C, and 0.2% of the original wastewater mass of hydrogen peroxide was added. The mixture was stirred at 60°C for 25 minutes, the pH was adjusted to 8.0, and the sludge was allowed to stand for separation to flocculate. The COD of the effluent was 850 mg / L, penicillin was not detected, and Cu was not detected. 2+ / Zn 2+ <1mg / L.

[0064] Step S50: The waste liquid treated in step S40 is passed through a two-stage chelating resin bed (Ca 2+ Removal efficiency >95%), the treated wastewater was introduced into a conductivity adjustment tank and diluted with pure water to a conductivity of ≤500 μS / cm. The diluted solution was pumped into a pulsed electric field reactor (electrode spacing 10.0 cm, field strength 2.0 kV / cm, pulse width 15 μs, frequency 2 kHz) for 12 minutes under nitrogen protection. 0.8 ppm ATMP scale inhibitor was simultaneously added. The treated wastewater was immediately pumped into a falling film evaporator (flow rate 2.2 m / s) and concentrated to 1 / 4 of the original volume at an operating temperature of 58°C and a pressure of -0.09 MPa.

[0065] Step S55: The concentrated liquid is pumped into the nanofiltration system with an operating pressure of 2.0 MPa, a TDS of the permeate of 3850 mg / L, and a desalination rate of >70%.

[0066] Step S55a: The evaporation condensate produced in step S50 is adsorbed with activated carbon to remove volatile organic compounds, so that the TOC of the condensate is 12 mg / L; the adsorption-saturated activated carbon is collected in step S35 to achieve activated carbon regeneration and then reused in step S50.

[0067] Step S60: The concentrated solution was tested for antibiotic residues (HPLC detection limit 0.01 mg / L), heavy metal content, and TDS of the permeate. The results showed that no antibiotic residues were detected (<0.01 mg / L), the heavy metal content was qualified, and the TDS of the permeate was 3850 mg / L, meeting the resource utilization requirements. 0.1% papain was added, and the concentrated solution was used to prepare organic fertilizer.

[0068] Results: The COD removal rate was 95%, and the proportion of effective heavy metals in the concentrate was less than 15% (detected by BCR continuous extraction method), which met the requirements of "NY / T 525-2021 Organic Fertilizer".

[0069] Example 2

[0070] Steps S10 to S20: Same as in Example 1.

[0071] Step S30: The pH of the supernatant was adjusted to 8.5, and activated carbon powder (100 mesh, 3% dosage) was added for an adsorption time of 100 minutes.

[0072] Step S35: Same as Example 1.

[0073] Step S40: The effluent from step S35 (COD: 9800 mg / L) was placed in an autoclave. Copper-iron composite oxide (0.7% by mass of the original wastewater) was added, and air was introduced to an oxygen partial pressure of 0.9 MPa. The reaction was carried out at 170°C for 50 minutes, reducing the COD to 920 mg / L. The reaction was then cooled to 62°C, and hydrogen peroxide (0.15% by mass of the original wastewater) was added. The reaction was stirred at 55°C for 20 minutes, and the pH was adjusted to 8.2. The reaction was allowed to stand for separation and flocculation of the sludge. The COD of the effluent was 800 mg / L, and no antibiotics were detected.

[0074] Step S50: The waste liquid treated in step S40 is passed through a two-stage chelating resin bed (Ca 2+ The solution was diluted to a conductivity of ≤500 μS / cm (removal efficiency >95%) and then pumped into a pulsed electric field reactor (electrode spacing 9.0 cm, field strength 1.8 kV / cm, pulse width 18 μs, frequency 1.5 kHz) for 13 minutes under nitrogen protection. 0.7 ppm ATMP was simultaneously added. The wastewater was then pumped into a falling-film evaporator (flow rate 2.0 m / s) and concentrated to 1 / 3.5 of the original volume at 57°C and -0.085 MPa.

[0075] Step S55: nanofiltration desalination (operating pressure 1.8 MPa), the permeate TDS is 3500 mg / L, and the desalination rate is >70%.

[0076] Step S55a: The evaporation condensate produced in step S50 is adsorbed with activated carbon to remove volatile organic compounds, so that the TOC of the condensate is 14 mg / L; the adsorption-saturated activated carbon is collected in step S35 to achieve activated carbon regeneration and then reused in step S50.

[0077] Step S60: The concentrated liquid is used to prepare organic fertilizer.

[0078] Results: The total COD removal rate was 94.5%, and the flocculated sludge contained 38 mg / kg of Cu (which can be smelted and recovered).

[0079] Example 3

[0080] Step S10: 1000 kg of waste liquid was taken, hydrochloric acid was added to adjust the pH to 3.2, and 0.7% of the mass of the original waste liquid of hydrogen peroxide was added to react at a reaction temperature of 45° C. and a reaction time of 40 minutes.

[0081] Step S20: Add 2% composite precipitant (FeSO4:Ca(OH)2=1:2.5), stir at a speed of 150 rpm, stir for 30 minutes, let stand for 30 minutes and separate the supernatant.

[0082] Step S30: The pH of the supernatant was adjusted to 8.0, and activated carbon powder (100 mesh, 2% dosage) was added, and the adsorption time was 90 minutes.

[0083] Step S35: Same as Example 1.

[0084] Step S40: The effluent from step S35 (COD: 12,500 mg / L, macrolides: 0.04 mg / L) was placed in an autoclave. A copper-iron composite oxide (0.6% by mass of the original wastewater) was added, and air was introduced to an oxygen partial pressure of 1.1 MPa. The reaction was carried out at 160°C for 75 minutes, reducing the COD to 1,050 mg / L. The reaction was then cooled to 60°C, and hydrogen peroxide (0.25% by mass of the original wastewater) was added. The reaction was stirred at 50°C for 30 minutes, and the pH was adjusted to 7.8. The reaction was allowed to stand for separation and flocculation of the sludge. The COD of the effluent was 900 mg / L, and no macrolides were detected.

[0085] Step S50: The waste liquid treated in step S40 is passed through a two-stage chelating resin bed (Ca 2+ The effluent was diluted to a conductivity of ≤500 μS / cm (removal efficiency >95%) and then pumped into a pulsed electric field reactor (electrode spacing 8.5 cm, field strength 2.2 kV / cm, pulse width 12 μs, frequency 2.5 kHz) for 14 minutes under nitrogen protection. 1.0 ppm ATMP was simultaneously added. The wastewater was then pumped into a falling-film evaporator (flow rate 1.8 m / s) and concentrated to 1 / 4.5 of the original volume at 56°C and -0.088 MPa.

[0086] Step S55: nanofiltration desalination (operating pressure 2.2 MPa), the permeate TDS is 3950 mg / L, and the desalination rate is >70%.

[0087] Step S55a: The evaporation condensate produced in step S50 is adsorbed with activated carbon to remove volatile organic compounds, so that the TOC of the condensate is 11 mg / L; the adsorption-saturated activated carbon is collected in step S35 to achieve activated carbon regeneration and then reused in step S50.

[0088] Step S60: Concentrate loading 10 8 CFU / g Bacillus subtilis was used to make soil remediation agent.

[0089] Results: The total COD removal rate was 92.8%, and the proportion of effective heavy metals was less than 10%.

[0090] Example 4

[0091] Step S10: Same as Example 1 (0.8% H2O2, 50°C / 50 minutes).

[0092] Step S20: Add 5% composite precipitant (FeSO4:Ca(OH)2=1:2.5), stir at a speed of 180 rpm, and stir for 60 minutes.

[0093] Step S30: The pH of the supernatant was adjusted to 8.5, and activated carbon powder (50 mesh, 3% dosage) was added, and the adsorption time was 120 minutes.

[0094] Step S35: Same as Example 1.

[0095] Step S40: The effluent from step S35 (COD: 8200 mg / L) was placed in an autoclave. A copper-iron composite oxide (1.0% by mass of the original wastewater) was added, and air was introduced to an oxygen partial pressure of 1.2 MPa. The reaction was conducted at 180°C for 45 minutes, reducing the COD to 780 mg / L. The reaction was then cooled to 70°C, and hydrogen peroxide (0.3% by mass of the original wastewater) was added. The reaction was stirred at 60°C for 25 minutes, and the pH was adjusted to 8.5. The reaction was allowed to stand for separation and flocculation of the sludge. The COD of the effluent was 700 mg / L, and no antibiotics were detected.

[0096] Step S50: The waste liquid treated in step S40 is passed through a two-stage chelating resin bed (Ca 2+ The effluent was diluted to a conductivity of ≤500 μS / cm (removal efficiency >95%) and then pumped into a pulsed electric field reactor (electrode spacing 11.0 cm, field strength 1.6 kV / cm, pulse width 18 μs, frequency 1.2 kHz) for 11 minutes under nitrogen protection. 0.6 ppm ATMP was simultaneously added. The wastewater was then pumped into a falling-film evaporator (flow rate 2.3 m / s) and concentrated to one-third of the original volume at 55°C and -0.092 MPa.

[0097] Step S55: nanofiltration desalination (operating pressure 1.6 MPa), the permeate TDS is 3200 mg / L, and the desalination rate is >70%.

[0098] Step S55a: The evaporation condensate produced in step S50 is adsorbed with activated carbon to remove volatile organic compounds, so that the TOC of the condensate is 9 mg / L; the adsorption-saturated activated carbon is collected in step S35 to achieve activated carbon regeneration and then reused in step S50.

[0099] Step S60: The concentrated liquid meets the standards and is used for the preparation of chemical raw materials.

[0100] Results: The total COD removal rate was 95.1%, the Cu recovery rate in the flocculated sludge was 91.2%, and Zn was not detected.

[0101] Example 5

[0102] Step S10: 1000 kg of cephalosporin waste liquid (initial TDS=65000 mg / L) was taken and subjected to acidification pre-oxidation treatment as in Example 1.

[0103] Steps S20 to S40: Parameters are the same as those in Example 1.

[0104] Step S50: The waste liquid treated in step S40 is passed through a two-stage chelating resin bed (Ca 2+ The effluent was diluted with pure water to a conductivity of ≤500 μS / cm. The diluted solution was then pumped into a pulsed electric field reactor (electrode spacing 12.0 cm, field strength 2.4 kV / cm, pulse width 16 μs, frequency 1.0 kHz) for 15 minutes under nitrogen protection. 1.0 ppm ATMP was then added. The wastewater was then pumped into a falling-film evaporator (flow rate 2.5 m / s) and concentrated at 58°C and -0.095 MPa to 1 / 4 the original volume. The concentrated solution had a TDS of 162,000 mg / L.

[0105] Step S55: The nanofiltration operating pressure is 2.4 MPa, and the permeate TDS is 18200 mg / L (salt rejection rate is 72.3%).

[0106] Step S55a: The evaporation condensate produced in step S50 is adsorbed with activated carbon to remove volatile organic compounds, so that the TOC of the condensate is 18 mg / L; the adsorption-saturated activated carbon is collected in step S35 to achieve activated carbon regeneration and then reused in step S50.

[0107] Note: Under high TDS conditions, it is necessary to increase the nanofiltration operating pressure (>2.0 MPa) and extend the pulse electric field time to 8 minutes to ensure a desalination rate of >70%.

[0108] Comparative Example 1

[0109] Compared with Example 1, hydrogen peroxide was not added in step S10, and the remaining steps were the same. The test results showed that the antibiotic residue was 0.25 mg / L, which was higher than the standard limit of 0.1 mg / L and could not be used to prepare organic fertilizers or chemical raw materials, proving the necessity of the pre-oxidation step.

[0110] Comparative Example 2

[0111] In step S50, vacuum evaporation (58°C) was used without adding a pulsed electric field and ATMP, reducing the volume of the waste liquid to 1 / 4 of the original liquid. In step S55, nanofiltration desalination (operating pressure 2.0 MPa) was performed, with a desalination rate of >70% and a permeate TDS of 15,500 mg / L. The remaining steps were the same as in Example 1.

[0112] The comparative experimental results are shown in Table 1:

[0113] Table 1

[0114]

[0115] The comparison of TDS and permeate data (unit: mg / L) is shown in Table 2:

[0116] Table 2

[0117]

[0118] The resource-based treatment method for antibiotic pharmaceutical wastewater provided by the present invention performs excellently across key performance indicators. In Examples 1-4, no antibiotic residues were detected, COD removal rates reached 94.5% to 95.1%, heavy metal content was consistently acceptable, and permeate TDS values ​​(3200 to 3950 mg / L) met the standard of ≤10,000 mg / L. Example 5 (initial TDS = 65,000 mg / L) still achieved a >70% salt rejection rate (permeate TDS = 18,200 mg / L) after adjusting nanofiltration parameters, demonstrating the process's adaptability to high-salinity wastewater. It should be noted that when the concentrate TDS is ≤50,000 mg / L, the permeate TDS must be ≤10,000 mg / L; when the concentrate TDS is >50,000 mg / L (e.g., Example 5), the permeate TDS is permitted to be ≤20,000 mg / L. Therefore, the scheme of the present invention can effectively degrade high-concentration organic matter and residual antibiotics, while achieving efficient recovery of activated carbon and resource utilization of soluble organic matter.

[0119] The comparative experiment verified the necessity of the key steps:

[0120] Comparative Example 1 did not undergo pre-oxidation, resulting in antibiotic residues as high as 0.25 mg / L (exceeding the standard), a COD removal rate of only 75% (significantly lower than Examples 1 to 4), unqualified heavy metals, and an excessive TDS value in the permeate (12600 mg / L). This indicates that the pre-oxidation step destroys the molecular structure of the antibiotic (e.g. β－ The lactam ring is broken), reducing its competitive consumption of •OH radicals in subsequent catalytic oxidation; and hydrolyzing macromolecular organic matter into small molecular fragments improves the reaction kinetics efficiency of catalytic wet oxidation (CWO), which is a key pre-step to ensure the overall process efficiency.

[0121] Comparative Example 2 used vacuum evaporation without the addition of a pulsed electric field and ATMP. Although the antibiotic residue and heavy metal levels met the standards, the COD removal rate (85%) and the activated carbon adsorption capacity retention rate (60.1%) were lower than those of the Example, and the TDS value of the permeate (15,500 mg / L) exceeded the standard. This verifies the advantages of vacuum evaporation with the addition of a pulsed electric field and ATMP in reducing energy consumption, improving the purity of the concentrate, and facilitating resource recovery efficiency.

[0122] Furthermore, the effects of vacuum evaporation temperature on the retention rate of active ingredients in the concentrate and the average size of crystal nuclei are shown in Table 3 (in step S50, the retention rates of active ingredients such as organic acids and amino acids in the concentrate were compared between atmospheric pressure evaporation at 80°C and vacuum evaporation at 58°C, and HPLC was used for detection):

[0123] Table 3

[0124]

[0125] The results in Table 3 show that the pulsed electric field crystal suppression technology combined with low-temperature vacuum evaporation increases the organic acid retention rate from 62.3% (using conventional evaporation) to 98.5%, and the amino acid retention rate from 58.7% to 97.2%. It also reduces the CaSO4 crystal nucleus size from 220nm to 38nm. This indicates that the retention rate of heat-sensitive nutrients has increased by over 36% (absolute value of organic acid retention +36.2%, amino acid +38.5%), and the crystal nucleus size has been reduced to 17% of the conventional value (38nm / 220nm), completely eliminating the evaporation scaling problem. Clearly, the pulsed electric field is the core factor in achieving the ultra-high retention rate of >97% in the present invention.

[0126] Furthermore, the influence of pulse electric field parameters on the crystal suppression effect is shown in Table 4:

[0127] Table 4

[0128]

[0129] The results in Table 4 show that when a 2kHz high-frequency pulsed electric field is combined with a field strength of 2.0kV / cm, the oscillation amplitude of the Zeta potential on the surface of the CaSO4 crystal nucleus reaches ±15mV (significantly improved compared to no electric field). By violently disturbing the double electric layer, the crystal nucleus growth is completely suppressed, and the TDS of the concentrated solution is reduced to 39500mg / L. At the same time, the energy consumption is reduced to 65kWh / t.

[0130] Furthermore, the experimental results of the effect of the composite precipitant ratio on heavy metal removal are shown in Table 5 (the total dosage of the precipitant in step S20 is fixed at 3.5%, the mass ratio of ferrous sulfate to calcium hydroxide is adjusted to 1:1, 1:2.5, and 1:3, respectively, and the heavy metal removal rate and precipitate volume are compared):

[0131] Table 5

[0132]

[0133] According to the results in Table 5, when the mass ratio is 1:3, the excess of Ca(OH)2 causes CaSO4 crystal expansion, and the sludge volume is close to that of the traditional Fenton process; when the mass ratio is 1:2.5, the sediment volume is the smallest (6.5%), and the heavy metal removal rate is greater than 98%. 2+ Calcium hydroxide absorbs heavy metal ions while simultaneously adjusting the pH to alkaline and generating CaSO4 crystal nuclei. The two work together to form dense flocs, reducing sludge volume and subsequent disposal costs. This ratio overcomes the efficiency bottleneck of traditional single precipitants.

[0134] Furthermore, the contribution of the pre-oxidation-catalytic oxidation synergistic effect to COD removal is shown in Table 6 (fixing other steps, comparing the treatment efficiency of "step S10 + step S40" and "step S40 catalytic oxidation", and testing key indicators at initial COD concentrations of 50,000 and 80,000 mg / L):

[0135] Table 6

[0136]

[0137] According to the results in Table 6, pre-oxidation hydrolyzes macromolecular organic matter (>500 Da) into small molecular fragments (<500 Da), which increases the mass transfer efficiency of ·OH radicals in catalytic oxidation by more than 50%; while the deconstruction of antibiotic molecules (such as β－ Lactam ring rupture) reduces its ineffective consumption of OH radicals, and the free radical utilization rate is increased by 35%. And under the ultra-high COD load of 80000mg / L, pre-oxidation makes catalytic wet oxidation － The iron flocculation removal rate increased from 79.6% to 94.8%, and the reaction time was shortened by 38% to 42%.

[0138] The performance comparison results of resource-based products are shown in Table 7:

[0139] Table 7

[0140]

[0141] According to the results in Table 7, the present invention ensures a high organic matter content (45%) while the effective state of heavy metals accounts for only 12% (35% for conventional technology), indicating that through the synergistic effect of chemical precipitation and iron flocculation, heavy metals such as Cu / Zn are converted into a stable residual state, significantly reducing environmental risks. 50 >1000 mg / kg (exceeding the national standard of 500 mg / kg), proving that the resource-based product poses extremely low risks to the soil ecosystem.

[0142] In summary, the various links of the present invention are closely linked, complementary, and interrelated. By optimizing multi-stage chemical and physicochemical processes and combining the physicochemical stabilization mechanism of heavy metals, it provides a reliable technical path with low environmental risks for the efficient resource recovery treatment of antibiotic pharmaceutical wastewater.

[0143] The above embodiments are only preferred implementation modes of the present invention and should not be used to limit the scope of protection of the present invention. Any changes or modifications that are made to the main design concept and spirit of the present invention and have no substantive significance, as long as the technical problems they solve are still consistent with the present invention, should be included in the scope of protection of the present invention.

Claims

1. A method for resource-based treatment of antibiotic pharmaceutical wastewater, characterized in that: The following steps are involved: S10: acidifying and pre-oxidizing the antibiotic fermentation wastewater in sequence; S20: adding a composite precipitant to the waste liquid treated in S10, stirring the mixture, and then allowing the mixture to settle, and separating the supernatant and the precipitate; S30: adjusting the pH of the supernatant obtained in S20 to 8-9 and performing adsorption treatment; S35: performing solid-liquid separation on the waste liquid treated in S30; S40: Add 0.5% to 1.0% of the mass of the original waste liquid to the waste liquid treated in S35, control the oxygen partial pressure to 0.8 to 1.2 MPa, and react at 160 to 180°C for 45 to 75 minutes; after the reaction, cool to 60 to 70°C, add 0.1% to 0.3% of the mass of the original waste liquid, stir at 50 to 60°C for 20 to 30 minutes, adjust the pH to 7.5 to 8.5 to generate Fe(OH)3 colloid, and let it stand to separate the flocculated sludge; S50: The waste liquid treated in S40 is subjected to chelation to remove calcium ions, and is subjected to pulse electric field suppression crystallization treatment and vacuum evaporation concentration to reduce the volume of the waste liquid to 1 / 5 to 1 / 3 of the original waste liquid to obtain a concentrated solution; S55: The concentrate is desalted by nanofiltration at an operating pressure of 1.5-2.5 MPa; S60: Detect antibiotic residues, heavy metal content and salt concentration of nanofiltration permeate in the concentrate, add synergists according to the type of antibiotics, and then use the concentrate to prepare organic fertilizers or chemical raw materials.

2. The method for recycling antibiotic pharmaceutical waste liquid according to claim 1, characterized in that: In S10, the antibiotic fermentation waste liquid is acidified and the pH is adjusted to 3.0-3.8, and then hydrogen peroxide is added for pre-oxidation reaction. The amount of hydrogen peroxide added is 0.7%-0.9% of the mass of the original waste liquid, the reaction temperature is 45-55° C., and the reaction time is 40-50 minutes.

3. The method for resource recovery of antibiotic pharmaceutical waste liquid according to claim 2, characterized in that: The composite precipitant in S20 is a mixture of ferrous sulfate and calcium hydroxide in a mass ratio of 1:2.

5. The dosage is 2% to 5% of the mass of the original waste liquid. The reaction is stirred for 30 to 60 minutes at a stirring speed of 120 to 180 revolutions per minute.

4. The method for recycling antibiotic pharmaceutical waste liquid according to claim 3, characterized in that: In S30, activated carbon is used for adsorption treatment; the mesh size of the activated carbon powder is 50 to 100 meshes, the addition amount is 2% to 3% of the original waste liquid mass, and the adsorption time is 90 to 120 minutes.

5. The method for resource recovery of antibiotic pharmaceutical waste liquid according to claim 4, characterized in that: In S35, the activated carbon is recovered and regenerated by a thermal regeneration method and then reused in S30.

6. The method for resource recovery of antibiotic pharmaceutical waste liquid according to any one of claims 1 to 5, characterized in that: The dosage of copper-iron composite oxide in S40 is 0.7% to 0.9% of the mass of the original waste liquid, the reaction temperature is 170 to 175°C, and the oxygen partial pressure is 1.0 to 1.1 MPa.

7. The method for resource recovery of antibiotic pharmaceutical waste liquid according to claim 6, characterized in that: The amount of hydrogen peroxide added to S40 is 0.15% to 0.25% of the original waste liquid mass, and the pH is adjusted to 8.0 to 8.

2.

8. The method for recycling antibiotic pharmaceutical waste liquid according to claim 7, characterized in that: S50 includes the following steps: S501: The wastewater treated in S40 is passed through a two-stage chelating resin bed to remove more than 95% of calcium ions, and then introduced into a conductivity adjustment tank and diluted with pure water to a conductivity of ≤500 μS / cm; S502: The diluted liquid is pumped into a pulsed electric field reactor and treated under nitrogen protection for 10 to 15 minutes, and 0.5 to 1.0 ppm ATMP scale inhibitor is simultaneously added. The parameters of the pulsed electric field reactor are: electrode spacing 8.0 to 12.0 cm, field strength 1.5 to 2.5 kV / cm, frequency 1 to 3 kHz, and pulse width 10 to 20 μs. S503: The treated waste liquid is immediately pumped into a falling film evaporator and concentrated to 1 / 5 to 1 / 3 of the original waste liquid volume at an operating temperature of 55 to 58°C and a pressure of -0.085 to -0.095 MPa; the flow rate of the falling film evaporator is 1.8 to 2.5 m / s.

9. The method for resource recovery of antibiotic pharmaceutical waste liquid according to claim 8, characterized in that: The process also includes S55a: removing volatile organic compounds from the evaporated condensate produced in S50 by adsorbing the activated carbon; and the adsorbed saturated activated carbon is fed into S35 to regenerate the activated carbon and then reused in S50.

10. The method for resource recovery of antibiotic pharmaceutical waste liquid according to claim 1 or 2 or 3 or 4 or 5 or 7 or 8 or 9, characterized in that: In S60, when the antibiotic residue is less than 0.15 mg / L, the heavy metal content satisfies Cu≤50 mg / kg, Zn≤200 mg / kg, and the permeate TDS≤10000 mg / L, a synergist is added according to the type of antibiotic; the synergist is papain or Bacillus subtilis.

Images