Research Progress on Occurrence, Removal and Fate of Microplastics in WWTPs

Abstract

WWTPs are considered to be a major indirect source of MPs discharged into the environment. Characteristics of MPs in the influent and effluent water and sludge of WWTPs were analysed, including abundance, type, shape and size. Detailed comparisons were made to summarise the removal efficiency of each treatment process on MPs and the analysis of the factors affecting them, and to analyse the trend of MPs attribution in WWTPs. It is also concluded that the main shapes of MPs in the influent and effluent water of sewage plants are fibres and fragments, in which fibres account for an increased proportion in the outlet water, and the main polymer types are PP, PE, PA and PET; the shapes of MPs in sludge are mainly fibres, and the main polymer types are PP, PE and PET; and the removal of MPs mainly relies on the physical effects of adsorption, interception, flocculation, filtration, precipitation, and so on.