Elangovan G, Balasundaram N, Ilangovan R, Sivaraju S S
Greywater generated from household activities is an important source of wastewater from households that has to be treated before reuse or disposal. The present study deals with the development and evaluation of a compact four-chamber greywater treatment system under field conditions. The novelty of the proposed system lies in integrating Eco Bio Block (EBB), BioClean microbial culture, Nano-Nualgi solution, and hypochlorous acid (HOCl) disinfection within a compact four-chamber treatment unit designed for household-scale applications. The system provides a simple, low-energy, decentralized solution for greywater recycling, making it suitable for domestic non-potable reuse where space and operational requirements are limited. The system combines EBB, BioClean microbial culture, Nano-Nualgi solution, and HOCl for sequential biological and disinfection treatment. The performance of the system was evaluated based on key water quality parameters such as pH, total suspended solids (TSS), total dissolved solids (TDS), electrical conductivity (EC), biochemical oxygen demand (BOD₅), chemical oxygen demand (COD), total phosphorus, total nitrogen, and E. coli. As evidenced by the results, the quality of treated water improved significantly, with removal efficiencies varying by parameter and maximum reductions exceeding 95% for selected pollutants. After treatment, significant decreases were observed in TSS, BOD₅, COD, nutrients, and microbial load. Treated samples contained <1.8 MPN/100 mL, indicating effective treatment of E. coli. HOCl contributed to pathogen removal, while biological treatment processes reduced organic load. The study confirms that the proposed system can function as an efficient, decentralized greywater treatment system suitable for non-potable reuse applications.