Behaviour of Alkylphenol Polyethoxylate Surfactants and of Nitrilotriacetate in Sewage Treatment

摘要: Effluents and sludges from several municipal sewage treatment plants in Switzerland were analyzed for nonylphenol polyethoxylates (NPnEO, n=3-20), mono- diethoxylate (NPlEO, NP2EO), corresponding nonylphenoxy carboxylic acids (NP1EC, NP2EC) (NP). These chemicals derive nonionic surfactants of the NPnEO-type, specific analitical techniques used to study their behaviour during mechanical-biological subsequent sludge treatment. The parent NPnEO-surfactants, with concentrations raw mechanically treated 400-2200 mg/m 3 , relatively efficiently removed by activated abundances different metabolites varied depending on conditions. refractory nature NPl/2EO, NP NPl/2EC was recognized. Both biotransformations physico-chemical processes determine fate nonylphenolic substances Nitrilotriacetate (NTA) found primary effluents at between 430 1390 . various showed removal efficiencies NTA operating Activated low loading rates nitrifying conditions 95 99%. High caused a decrease 70% 39%.