Investigation of municipal wastewater treatment by agricultural waste materials in locally designed trickling filter for peri-urban agriculture

Abstract

A pilot scale trickling filter system was designed, developed, and operated using a constant recirculation method for treatment of municipal wastewater. Maize cob (TF1) and date palm fibre (TF2) were used as biofilm support media in a trickling filter system. Both the TF1 and TF2 were compared based on the removal efficiency of pollution indicators such as biological oxygen demand (BOD), chemical oxygen demand (COD), total dissolved solids (TDS), total suspended solids (TSS), electrical conductivity (EC), total nitrogen (TN), total phosphorus (TP) and sulphates. The hydraulic flow rate and loading were set as 0.432 m3/h and 0.0064 m3/m2.minute, respectively at temperature range of 15–42 °C for 15 operational weeks. Both the TF1 and TF2 showed acceptable removal efficiency (61% to 76.3%) for pathogen indicators such as total count, fecal coliforms and Escherichia coli. However, 8–15% higher removal efficiency was observed for TF1 for all the pollution indicators compared to TF2. The results suggest that both the biofilm support media in trickling filter have potential to treat municipal wastewater in peri-urban small communities to produce environmentally friendly effluent. HIGHLIGHTS Agricultural waste-based biofilm support media.; Removal of carbonaceous and nitrogenous contaminants.; Log reduction of pathogen indicators.; Maize cob media is more efficient than date palm fiber.;

Keywords

• date palm fibre
• maize cob
• peri-urban agriculture
• trickling filter
• wastewater treatment