A comparative study on treatment technologies for sewage reclamation: A focus on the disinfection process

Abstract

Selection of suitable disinfection technology is necessary with regards to wastewater reclamation goals. In this work, the performance of various disinfection technologies-single disinfection units and integrated disinfection systems-on local sewage was studied for non-potable reuse. Disinfection units used as stand-alone units include ultraviolet (UV) disinfection, chlorination, microfiltration (MF), and ultrafiltration (UF). The integrated disinfection system consists of UV or chlorination as the primary disinfection unit incorporated with either MF, UF, multi-media or granular activated carbon as pre-treatment. The performance of these disinfection units and integrated processes were evaluated based on the percentage of removal of biochemical oxygen demand, chemical oxygen demand, total suspended solids, ammoniacal nitrogen, nitrate nitrogen, phosphorus, Escherichia coli, and trihalomethane in bench-scale disinfection systems. The single unit of PES20kDa membrane and the integrated disinfection system of UF-Cl showed the most effective treatment among single disinfection units and integrated systems, respectively. The results showed that almost all disinfection units and integrated disinfection processes were useable for restricted and unrestricted area non-potable applications according to United State Environmental Protection Agency (US EPA) water reuse guidelines and managed to fulfil Singapore grey water quality for recycling.