| The characteristics of Semi-synthetic antibiotics waste water are high pollutants concentration, complex composition, and chemical stability. Semi-synthetic antibiotics wastewater treatment technology mainly consist physical treatment, chemical treatment, biological treatments and its combination. However, the residual antibiotics in the wastewater have a strong inhibitory effect on biological species, so it is difficult to play the advantages of biological treatment. The main issues include low COD removal efficient, high operating costs and the difficulty to reach the emissions standards. In view of the fact that Semi-synthetic antibiotics waste water is difficult to be biodegraded,the author, on the basis of systematic study, puts forward a pretreatment using advanced oxidation processes, and the Fenton, electro-catalytic oxidation and bio-oxidation test pilot was conducted. The feasibility of the pretreatment using Advanced Oxidation Processes for semi-synthetic waste water was discussed, and then the impact effect and mechanism of the treatment of semi-synthetic antibiotics using Fenton reagent and electricity Oxidation were studied.Fenton experiment showed: influencing factors of COD removal effect were: [FeSO4]> [H2O2]> pH> [flocculent]. At pH=3, [FeSO4]=240 mg/L, [H2O2]=1 mL/L, [flocculants]=1 mg/L, stirring time=30 min, COD removal efficiency was best and the removal of COD was 29.4%.Electro-catalytic oxidation experiment showed: The best process parameters was: slot spacing 60 cm, voltage 50 V, air flow 50 L/h. Ultrasonic could improve COD removal efficiency. On the initial response phase, the wastewater COD removal rate increased soon, but after 20min the COD removal rate growth slowed down. When the reaction time was 30min, COD removal rate of ampicillin waste water, amoxicillin waste water, amoxicillin waste water removing condensation mother liquor and ceftriaxone waste water reached 55%, 25%, 39% and 35%. There were flocculation-generated in the process of dealing with different waste water, two-stage treatment may slowed the effect of coagulation. COD removal efficiency of ceftriaxone integrated waste water and ampicillin/amoxicillin waste water treated by two-stage electro-catalyzed oxygen could reach 62.1% and 74.6%, better than the single-stage effect.Biological treatment tests showed that: without a pretreatment of wastewater, when the system operated for some time, the COD removal rate dropped significantly. Even the influent COD concentration was decreased; it was still difficult to restore the system. When the waste water pretreated by electro-catalytic oxidation was treated by acid hydrolysis, anaerobic digestion and aerobic biological treatment, COD removal rates reached respectively 20 to 40%, 60%, 76 to 80%, indicating that the Biodegradability of wastewater had been improved remarkably. In the acid hydrolysis-anaerobic-aerobic biological treatment plant, a similar result can be obtained. When the influent COD concentration was about 6000 mg/L, the final effluent COD concentration could be stabilized at 250 mg/L, the total COD removal rate reached 95.7 %.On-site engineering operation showed that semi-synthetic antibiotics waste water was processed by electro-catalytic oxidation, COD removal rate could be stabilized at around 54.1%, and the COD removal efficient did not decreased after the system run a month. With voltage 40 V, average current 300 A, 5 t/h influent water, the power consumption was 24 kW, that is, 4.8 degrees percent tons of waste water.More than the pilot test and engineering show that advanced oxidation processes can be used for the pretreatment of semi-synthetic antibiotics wastewater. The waste water dealing with Electro-catalytic oxidation technology, COD removal rate can reach 60%, and also can significantly improve the biodegradability of waste water, creating the conditions for the follow-up biological processing .so it is a viable technology.
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