Treatment Of High Concentration Pharmaceutical Wastewater By Process Of Fe/C Electrolysis-anaerobic Hydrolyze-microalgae

The characteristics of pharmaceutical wastewater are difficult to biodegrade,with high organic matter,high toxicity,using s single water treatment technology can not meet the emission standards.To solve the problem,in this paper,Fe/C electrolysis–anaerobic hydrolyze-microalgae was adopted as the treatment of high concentration pharmaceutical wastewater,and the effluent quality can meet the emission standards of the pharmaceutical industry water pollution discharge standard.It provides some theoretical basis for economical and efficient treatment of high concentration pharmaceutical wastewater.Accordingto the source,hazard and characteristics of pharmaceutical wastewater,the pretreatment of high concentration pharmaceutical wastewater by Fe/C electrolysis technology is adopted to improve the biodegradability of wastewater.The optimal experimental conditions of Fe/C electrolysis deduced from single factor experiments and orthogonal test:the dosage of Fe/C was 600 mg/L,initial pH was 4,coagulation pH was 9,reaction time was 2.5 h,the dosage of PAM was 1 mg/L,aeration intensity was 1.5 ml/min.Under these conditions,COD?colority?NH₃-N and TP removal rate were 55%,80%,36%,63%,respectively.And BOD₅/COD was increased from 0.12 to 0.35,the biodegradability of pharmaceutical wastewater was increased dramatically.By GPC and GC-MS analysis,it was founded that the organic components in the pharmaceutical water including 4 main categories:ethers compounds,esters compounds,nitrogen-containing heterocyclic compounds and other organic compounds,the nitrogen-containing heterocyclic compounds were 64.592%,the wastewater including many molecular structures and functional groups,and the biodegradability of wastewater was low.By Fe/C electrolysis,the types of total organic compounds in wastewater were significantly reduced,and the complex macromolecules in the nitrogen-containing heterocyclic compounds were completely degraded.Fe/C electrolysis degraded complex macromolecular organic compounds and toxic and harmful substances through the reaction of primary cell and oxidation reduction,some complex functional groups,such as aromatic hydrocarbon and azo,have been destroyed to improve the biodegradability of wastewater.The influent pH,hydraulic retention time and reflux ratio have great influence on the pollutant removal efficiency of external circulation anaerobic reactor.The optimal conditions of anaerobic reactor were:pH value was 7.0,HRT was 2h,and reflux ratio was 3,the COD removal efficiency reached 85%,it concluded that most organic pollutants in wastewater could effectively removed by biological treatment.The microalgae cultivated by heterotrophy using anaerobic effluent,a certain of biological accumulation could be achieved during the 10 d incubation period without addition of other nutrients.The pretreatment of high temperature sterilization can significantly improve the wastewater treatment effect.COD?NH₃-N and TP removal rate were 55%,80%,36%.Under the total technology system,the effluent with the characteristics of COD<200 mg/L,TP<2 mg/L and NH₃-N<40 mg/L and can meet the standard of the"Chemical Synthetic Pharmaceutical Wastewater Discharge Standard"?GB 21904-2008?.