Disinfection methods for wastewater aiming reuse: a review

This review presents disinfection technologies and formation of disinfection by-products (DBPs) in treated wastewater, highlighting their efficiency and applicability for reuse. Chlorine, peracetic acid (PAA), ozone (O3), performic acid (PFA), permaleic acid (PMA), persulfate (PSA), and ultraviolet (UV) radiation were evaluated, individually or in combined processes. Chlorination (0.8–30 mg/L) can achieve up to 8 Log microbial reduction but generates DBPs of up to 33 µg/L. PAA (1–8 mg/L) provides similar removal with minimal DBP formation (< 0.5 µg/L). Ozone (0.3–10 mg/L) reaches 6 Log reduction and significantly decreases DBP formation. Emerging oxidants such as PFA, PMA, and PSA achieve up to 5 Log removal with low DBP levels, although they present stability and cost limitations. UV radiation in advanced processes enhances microbial inactivation (up to 7 Log) while maintaining low DBP concentrations. Physicochemical characteristics influence these removal efficiencies as well as the suitability of the treated effluent for different reuse standards.