The Removal of PAHs and PAEs in the Process of Orbal Oxidation Ditch

Method for simultaneous analyzing the residual of PAEs & PAHs in municipal wastewater by solid phase extraction coupled with gas chromatography was established. The proposed methods were used for the analysis of 16 PAHs & 6 PAEs of the municipal wastewater in Xi´an. NAPT, ACNY, ACEN, FLUR, PHEN, DMP, ANTH, PYR, DEP, DEHP, DBP, and BBP were quite frequently observed in influent. The analytes of greatest concentration were NAPT, FLUR, PYR, PHEN and DEHP. However, B (b) F, D (a,h) A, B (a)P, B (k)F, DOP rarely detected. The elimination of these chemicals through municipal wastewater treatment with methods of the Aeration Settling Tank, the Orbal Oxidation Ditch and the Final Settling Tank were investigated. Apparent reduction of PAEs concentrations was found along the municipal treatment process. The secondary treatment could remove the total PAHs and PAEs by 78.41% and 69.52% of which 62.19% and 52.65% were removed by the biological treatment unit, respectively.