Two-stage A/O Process For Antibiotic Of Piggery Wastewater Treatment

With the rapid development of intensive livestock and poultry farming,the quantity of the scale of the large-scale pig farm is increasing gradually,it is not allowed to be ignored with the ecological security problems caused by the pollution of veterinary antibiotics.The present research of pigs wastewater treatment at home and abroad mostly focus on improving the existing process system and developing efficient reactor,but the antibiotics in pig wastewater pollution and removing is relatively rare to be further researched.Therefore,the study of the removal of veterinary antibiotics from large-scale pig wastewater treatment technology has been imperative.Combining with the actual engineering situation,antibiotic-sulfanilamide,tylosin and ciprofloxacin-wastewater treatment efficiency of multistage A/O system and the influence of the distribution of antibiotics in sewage treatment system has been reasearched as the object.The specific contents are as follows.In this paper,multistage A/O process model is established based on a pig farm wastewater treatment engineering in Chongqing,the Residence time distribution density function of the unit pool and the whole pool has been studied.The residence time distribution density function of the unit pool:E?t?= 0.0434exp?-0.0434t + 0.174?t>4h E?t?= 0 0<t<4h The residence time distribution density function of t the whole pool:E?t?= 7383300.7?t/120?¹⁹exp?-t/6?Multistage A/O process system started with the natural hanging membrane.When the system stable running,the system of chemical oxygen demand?COD?,total nitrogen?TN?,total phosphorus?TP?removal efficiency are 87.97%,91.43%and 73.47%respectively.1 mg/L sulfanilamide,tylosin,ciprofloxacin and the blend of three antibiotics drugs are added in the inlet water,the results showed that the system for the average removal efficiency of COD,TN and TP were dropped to 76.87%,84.88%and 57.80%with 1 mg/L of sulfanilamide added into the water.But it has little impact on biology removal efficiency of the system with 1 mg/L of tylosin,the average removal efficiency of COD,TN and TP had fellen to 82.82%,82.82%and 82.82%respectively.For the 1 mg/L of ciprofloxacin,the system's average removal efficiency of COD,TN and TP had fallen to 52.26%,80.82%and 54.13%respectively.With 1 mg/L mixed antibiotics added into the water,the average removal efficiency of COD,TN and TP were dropped to 66.46%,82.37%and 56.89%.The target antibiotics have been different degrees of removal from the multistage A/O system,the removal efficiency of tylosin is most significant,which is up to 93.92%.But it is only 65.29%for sulfanilamide,and the removal rate of ciprofloxacin was 91.52%,it was 87.40%for mixed antibiotics.This paper focuses on studying the hydrolysis of three kinds of antibiotics?sulfamethazine,tylosin,ciprofloxacin?in the environment by the method of high performance liquid chromatography.It turns out that there is no hydrolysis reaction in sulfamethazine,tylosin.Different pH value,water environment,temperature,dissolve of oxygen have little influence on the hydrolysis of these antibiotics.However,the light,to some extent,has impact on the hydrolysis.Compared with the samples in the dark,in the same period,as for the ones in the light,the residues of the antibiotics all decrease to some extent,the amount of the decrease almost equals the amount of photolysis.In a week,photolysis rate of the sulfamethazine is 3.2%,with the tylosin 28%and ciprofloxacin 2.7%.Concerning the antibiotic hydrolysis,photolysis and multi A/O system of each unit for the removal of antibiotics,the results showed that the level of anaerobic pool removal effect of antibiotics is considerable,the removal of the unit of sulfamethazine,tylosin,ciprofloxacin,mixed antibiotic rate were 43.76%,45.19%60.51%and 54.98%.