Research On The Effect And Fate Of Oxytetracycline During The Anaerobic Digestion Of Sludeg

China produces 10,000 tons of oxytetracycline every year, accounting for 65% of world production, and the production process produces high concentrations of oxytetracycline wastewater. In addition, it is widely used in veterinary medicine as a cheap livestock and aquaculture. More than 80% of the original drug oxytetracycline will be discharged to the body with excrement and eventually into aquaculture wastewater.So there is a lot of production wastewater and aquaculture wastewater containing oxytetracycline need be treatmented by WWTP annually. In the process, the sludge adsorption of oxytetracycline is the most important way to remove oxytetracycline. The vast majority of oxytetracycline transfer from wastewater to sludge by adsorption. So there is a large amount of sludge containing oxytetracycline. At present, the majority of the final disposition of the sludge is landfill. If sludge containing oxytetracycline isn’t treatmented appropriately, the soil will cause serious harm to the environment. Anaerobic digestion is the current primary sludge treatment process, so the research anaerobic digestion process of sewage treatment plant sludge containing oxytetracycline has important significance.This paper studied the mesophilic anaerobic digestion and thermophilic anaerobic pretreatment of oxytetracycline degradation and suppression of oxytetracycline through using static batch experiments and dynamic semi-continuous flow completely mixed reactor. And this paper also studied the OTC degradation pathway in anaerobic digestion, and microbial community structure evolution at different concentrations of oxytetracycline oppression.Static batch experiments showed that biogas production was reduced by 17.24% at OTC concentrations of 5mg / L. And when up to 100 mg / L, biogas production was reduced by 58.43%. In addition, through sterilization group and the group of non-sterilized batch experiment results, run for 15 days, 23.92% oxytetracycline degrated by hydrolysis, and degradation through biological degradation pathways of oxytetracycline reached 37.82%. The overall degradation rate reached 61.74%. Therefore biodegradation is oxytetracycline main degradation pathway of sludge digestion.By semi-continuous flow of single phase mesophilic anaerobic reactor operation and analysis concluded that oxytetracycline into the sludge content 5mg / L, 30 mg / L, 100 mg / L when, for biogas production cuts were 17.24%, 21.00%, 26.36%, while OTC degradation rates were 56.06% ~ 63.46%, 48.05%, 63.26%. After the front-end thermophilic anaerobic pre-treatment, the above oxytetracycline concentration of biogas production cuts were 5.29%, 5.84%, 9.22%, of oxytetracycline overall degradation rate reached 81.67% ~ 87.04%, 83.96 %, 86.19%. It shows thermophilic anaerobic pre-treatment can effectively enhance the removal of oxytetracycline and mitigate its inhibition of biogas production.The results of T_RFLP showed that with the increases of oxytetracycline concentration, the dominant populations of bacteria and archaea continue to occur in succession, community structure is constantly changing. It indicated that the community of microorganisms adjusted its structure in order to better adapt to higher concentration of oxytetracycline and environmental changes.In summary, the conventional mesophilic anaerobic digestion process for the removal of oxytetracycline has a certain role, with thermophilic anaerobic pretreatment of oxytetracycline removal can be increased to about 85%, effectively reduce emissions of oxytetracycline. The technology is mature and reliable and it has some practical engineering.