Distribution characteristics of microplastics in storm-drain inlet sediments affected by the types of urban functional areas, economic and demographic conditions in southern Beijing.

A storm-drain inlet is an important link in the transport of microplastic pollutants in urban rainwater runoff. In three functional districts (agricultural, commercial, and residential) from Beijing South 2nd Ring Road to South 6th Ring Road, microplastics in storm-drain inlet sediments were analyzed for abundance and characteristics. The abundance of microplastics in the collected samples ranged from 1121 ± 247 items kg to 7393 ± 491 items kg.

Improving sludge dewaterability via Fe chelated citrate activated peroxydisulfate oxidation.

Citrate (Ct) was chosen as a typical chelator used in the Fe-peroxydisulfate (PDS) process to improve sludge dewaterability. The PDS-Fe-Ct process exhibited better performance in sludge dewatering than PDS-Fe. Specifically, with a PDS dosage of 1.