Performance of an Integrated Settler Based Anaerobic Biofilm Reactor as Onsite Sanitation System

Abstract

The present study analysed the performance of an integrated settler based anaerobic biofilm reactor (ISBABR) for domestic wastewater treatment at two hydraulic loading conditions as an onsite sanitation system. The ISBABR is designed on the basic concept of conventional septic tanks and anaerobic biofilm reactors. The ISBABR was run on actual sewage after inoculating it with digested sludge, whose COD (Chemical oxygen demand) and VSS (Volatile suspended solids) values were 9.65 and 7.13 g/l respectively. The system was operated on steady and non-steady hydraulic loading conditions while maintaining 24 h HRT for 4 consecutive months. The average removal efficiency of the system in terms of TSS (Total suspended solids), BOD (Biochemical oxygen demand) and COD was found to be 90.09 ± 4.5%, 89.89 ± 3.2% and 87.89 ± 5.2% respectively, under both the hydraulic loading conditions. In bacterial analysis, the removal efficiency of the system in terms of TC (Total coliform) and FC (Fecal coliform) was found to be 85.5 ± 4.9% and 96.36 ± 1.5% respectively. The morphology of the sludge showed the presence of anaerobes, which was a good indicator for the system. The results of the present study prove that the ISBABR is perfect system for onsite sanitation.