Phthalate Removal Throughout Wastewater Treatment Plant Case Study Of Marne Aval Station (france)

摘要

The fate of six phthalates: dimethyl phthalate (DMP), diethyl phthalate (DEP), di-n-butylrnphthalate (DnBP), butyl benzyl phthalate (BBP), bis (2-ethylhexyl) phthalate (DEHP) and di-noctyl phthalate (DnOP) was investigated throughout wastewater treatment processes in thernwastewater treatment plant (WWTP) of Marne Aval (France). That plant treats wastewaterrnfrom a highly populated area and was used as a pilot station for development of nitrification processes.rnIn wastewater, at each step of treatment, DEHP was always the major compound (9 to 44 μg L~(-1)), followed by DEP (1.6 to 25 μg L~(-1)). Other phthalates averaged 1 μg L~(-1) and DnOP remained close to the detection limit in nearly all cases.rnIn sludge, the prevailing compound was also DEHP (72 μg L~(-1)) which is consistent with its tendency to get sorbed upon suspended matter (SM). DnOP came in third, in relation with itsrnresistance to biodegradation.rnFor the studied period, the removal efficiency of DEHP from wastewater was about 78%. Thatrnremoval seemed to proceed rather from particle settling than from biodegradation. A highlyrnsignificant correlation (p< 0.001) was found between DEHP and SM concentrations throughoutrntreatment processes. The other compounds: DMP, DEP, DnBP and BBP, displayed satisfactoryrnefficiencies ranging from 68 to over 96% for the lighter ones obviously more easily degraded.rnUnder rainy periods, the plant discharge impact upon Marne River quality in terms ofrnphthalate fluxes, appeared to be minor as compared to the amount brought by the stormrnoverflows in the same area. Downstream of the WWTP discharge, DEHP concentrationrnremained under the European norm for surface water (NQE: 1.3 μg L~(-1)).rnOur study documents the behaviour of phthalate esters throughout a WWTP whichrntreatment device is used by 55% of the WWTP in the river Seine basin.