Novel two-stage vertical flow biofilter system for efficient treatment of decentralized domestic wastewater.

Highlights: [•] Thin iron scraps layer paved in the trickling filter enhanced the TP removal. [•] Zeolite trickling filter under intermittent water feeding benefits nitrification. [•] Coarse media in the first stage inhibits clogging of the latter infiltration stage. [•] Better influent dispersion for MSL was achieved owing to the two-stage design. [•] Two-stage filter system appeals to decentralized treatment of sewage well. [ABSTRACT FROM AUTHOR]