Journal of Advanced Chemical Engineering

Abstract

Application of Dual Media Biofilm Reactors for Removing Organic Matter and Ammonia from Pesticide Wastewaters

Khim Hoong Chu, Xiao Feng, and Gang Yuan

This study investigated the aerobic treatment of two different types of wastewaters emanating from manufacture of pyrethroid and organophosphorus pesticides in dual media biofilm reactors packed with polyurethane foam and Pall ring. Two dual media reactors were employed: one reactor treating a pyrethroid pesticide wastewater containing 4000–4400 mg/L of chemical oxygen demand (COD) and 135–200 mg/L of ammonia and the other an organophosphorus pesticide wastewater containing 6400– 7200 mg/L of COD and 50–160 mg/L of ammonia. Over 84% of COD and 97% of ammonia were removed in the reactor receiving the pyrethroid pesticide wastewater with 48 h of hydraulic retention time (HRT). Conversely, with 72 h of HRT the reactor treating the organophosphorus pesticide wastewater demonstrated a limited treatment capability, achieving a lower COD removal efficiency of 77% and exhibiting no ammonia removal.