Characteristics Of Indole And Naphthalene In Pharmaceutical Wastewater Treatment By Bio-enhancement Activated Sludge Process

As a difficult problem in the field of industrial wastewater treatment,pharmaceutical wastewater is characterized by complicated composition,large variation of water quality and amount,containing a large number of refractory organic pollutants,most of these organic compounds is biological inhibitory substances.Researches of pharmaceutical wastewater mostly focused on the overall wastewater treatment or physical mechanism research,less in the research of typical pollutants reduction technology advanced treatment.This topic mainly focused on naphthalene and indole in pharmaceutical wastewater,combining biological strengthening technology with good effect,low cost sewage treatment technology,in order to achieve the effective removal of pollutants.The study used co-metabolism in bio-enhance technology domesticated activated sludge,mixed efficient degradation bacteria and cultivated,dropped it in continuous operation reactor,moving bed biofilm reactor(MBBR)and total reflux sludge reactor process(STR)system.The test mainly performed the optimization of the operation parameters of the reactor,removal efficiency of pollutants under the condition of stable operation,the effects on pollutants removal efficiency and the change of microbial system in the test of organic pollutants impact load,that was suitable for advantage bacterium group grow,strong ability to resist impact load of process system.For keeping higher activity and degradation ability in practical environment,the pollutant concentration higher than the actual concentration of the environment was setted in the process of microbial screening or training.According to the subject project report analysis,Choose two kind of refractory organic matter indoles and naphthalene as target pollutants,which was high contents in wastewater.Domesticated the advantage bacterium group with specific degradation efficiency.The result was that activated sludge can only survive with indole or naphthalene as the sole carbon source,could deal with high concentration of 200 mg/L and 60 mg/L,the degradation efficiency was 99% and 95% respectively.The optimal operation parameters of reactor: HRT was 8 h,aeration was 0.12 m3/h,The effect was better in 25±1? than that in 20± 2?.In the stable operation period,the average removal rate of COD and ammonia nitrogen MBBR system were 93.47% and 73.34% respectively,significantly higher than the STR system of 88.85% and 69%,the two kinds of target pollutants concentration in water was lower than the detection limit.In the organic pollutants joint impact load test,using gas chromatography to detect the content of target pollutants in water.With the improving of the indoles,naphthalene concentration in water,peak number in meteorological chromatograms gradually increased.In the fourth stage of the impact load test,STR system residual concentrations of naphthalene in produced water was exceed the target value of 0.1 mg/L.MBBR system average removal efficiency of COD and ammonia nitrogen is better than that in STR systems.Advantage bacterium group in the reactor have high degradation capacity of indole and naphthalene,activated sludge concentration was not fall under the condition of the improvement of toxic refractory organic matter concentration,but the system sludge activity showed a trend of decline.under microscope found that MBBR system kept high microbial activity.The existence of Clock bug,projecting fiber and rotifers marked the good effect of wastewater treatment,stable and mature sludge,richness of microbial species.Organic matter was degraded after adsorped by microorganism.Under the impact of the refractory organic matter,EPS on microorganism surface increased.The addition of EPS in microbial membrane of MBBR system was small relatively.Through highthroughput sequencing technologies,the existence of microorganisms under the condition of the complex water quality was analyzed.The results showed that dominant bacteria still occupied an important proportion in two reactors,and created some new species with adaption to the reactor environment and resistant to pollutants.