Most of the microplastic pollutants in urban wastewater are migrated to the remaining sludge during the wastewater treatment process.Elucidating their distribution characteristics is of great significance for clarifying the emission and environmental impact of microplastics from urban wastewater sources.Herein,three wastewater treatment plants(WWTPs)located in different administrative districts of Guangzhou were selected,and their wastewater and sludge samples were tracked and collected.The three WWTPs contributed a removal rate of over 95％for microplastics in wastewater.These microplastics were migrated to the remaining sludge.In the dry sludge,microplastic concentrations were(19.6±8.4),(39.5±15.6)g-1 and(15.9±4.8)g-1.The shapes of microplastics in sludge included spherical,irregular block,fibrous and film shapes.The spherical and fibrous shapes originated from domestic wastewater,while part of the irregular blocks originated from industrial sources.Among the detected microplastics,80％～90％had sizes in the range of 1μm to 100 μm.Moreover,there was a certain correlation between fibrous microplastics and larger size(50～100 µm)microplastics.Among the detected microplastics,transparent and white materials accounted for the main parts,with their quantity proportion ranging from 60％to 90％.In terms of materials,polyethylene and polypropylene microplastics accounted from 60％to 80％,while microplastics of more than a dozen other materials account for relatively small amounts.In summary,microplastics in WWTPs are closely related to their wastewater sources.
关键词
微塑料/污水处理/拉曼光谱/迁移转化/新污染物
Key words
microplastics(MP)/wastewater treatment/Raman spectrum/migration and transformation/novel pollutant
维普
万方数据