Treatment Of Amoxicillin Wastewater By Bio-film Method And Three-dimensional Electrode-Fenton Method

Antibiotic production and consumption in China are larger every year.Antibiotics are widely used in the fields of disease control,animal husbandry and aquaculture,agricultural production and so on.However,because of the low utilization of antibiotics in living organisms,a large number of antibiotics and residues are entered into the environment through various ways.It is becoming a new pollutant in the environment,which seriously threatens the safety of human health and ecological environment.Many of the existing sewage treatment equipment is not specifically targeted at antibiotics,it can not remove the antibiotics completely,this exacerbates the ecological risk of antibiotic contamination.This article takes amoxicillin wastwater as the research object.The activated carbon fiber bio-film method was used to treat the low concentration of amoxicillin wastewater.This paper explore the effects of different amoxicillin concentrations on the structure and diversity of microbial communities in biofilm by high throughput sequencing technique.For high concentrations of amoxicillin wastewater,bio-film method is no longer applicable,so three-dimensional electrode-fenton method is used to improve COD removal rate and biodegradability of wastewater.The conclusions are as follows.?1?Bio-film method take activated carbon fiber as the carrier,using activated sludge for inoculation,the bio-film reached a stable state after 20 days.In the presence of the substrate,the microorganism transforms amoxicillin into the main metabolic pathway through the Co-Metabolism effect,thus the amoxicillin concentration was decreased.At the same time,the microorganism on the biofilm and it's extracellular polymer also have adsorption to amoxicillin.When amoxicillin concentration was 30 mg/L,the removal rate of amoxicillin was the highest in the bio-film method,which reached 85.7%after 24 hour's reaction,and the removal efficiency was better than that of ordinary activated sludge method.?2?Different concentrations of amoxicillin have different effects on the structure and diversity of bacterial and fungal communities in biofilm.When there is a small amount of amoxicillin in water?0.25 mg/L,8 mg/L?,the bacteria and fungal communities have a certain stimulating effect,so that the richness and uniformity of the community increased slightly.When amoxicillin concentration exceeded 30 mg/L,the influence on bacteria and fungi community was greater,the richness and evenness of community decreased,and the dominant strains which could resist amoxicillin appeared.The Rudaeicoccus,Chryseobacterium and uncultured bacterium of Xanthomonadaceae are dominant bacteriain under high concentrations of amoxicillin?100 mg/L?.The Microcera,Myxocephala and Trichosporon are dominant species in fungi under high concentrations of amoxicillin?100 mg/L?.?3?The removal efficiency of COD in wastewater by three-dimensional electric-Fenton method is higher than electric-Fenton method and Fenton method.When the initial amoxicillin concentration was 100 mg/L,the effect of various factors on COD removal rate was analyzed,and the best operating conditions were obtained.Under the best operational condition:pH=3,the voltage is 12V,[H₂O₂]=12 mmol/L,[Fe²⁺]:[H₂O₂]=1:36,activated carbon dosing is 15 g/L,after 60 min,COD removal efficiency reached to 74.1%,BOD₅/COD is 0.44.