Removal of persistent organic pollutants and disinfection of pathogens from secondary treated municipal wastewater using advanced oxidation processes

Abstract

An affordable and sustainable tertiary treatment is imperative to solve the secondary contamination issues related to wastewater reuse. To decontaminate and disinfect the actual secondary treated wastewater, various types of advanced oxidation processes (AOPs) have been studied. The optimization of the oxidant and catalyst is carried out to identify the best-performing system. Under selected experimental conditions, UV/PMS, O3/PMS, UV/MnO2, O3/MnO2, UV/O3/H2O2, O3/MnO2/H2O2, UV/MnO2/H2O2, and UV/O3/MnO2 has identified as an efficient treatment option for simultaneous decontamination (>90% COD removal) and disinfection (100% inactivation of the total viable count of bacteria). The techno-economic assessment revealed that UV/MnO2 (23.5 $ kg−1 of COD) UV/O3/MnO2 (37.4 $ kg−1 of COD), UV/H2O2/MnO2 (36.4 $ kg−1 of COD), and O3/MnO2/H2O2 (32.5 $ kg−1 of COD) are comparatively low-cost treatment processes. Overall, UV/MnO2, UV/H2O2/MnO2, and O3/MnO2/H2O2 are the three best treatments. Nevertheless, further investigation on by-product and catalyst toxicity/recovery is needed. The results showed that AOPs are a technologically feasible treatment for removing persistent organic pollutants and pathogens from secondary treated wastewater.

Characteristics and application of iron-based materials in heterogeneous Fenton oxidation for wastewater treatment: a review

“…20–22 This process is simple, efficient, and environmentally benign. Ganesh Kumar et al 23 used a combination of UV/Fe 2+ /H 2 O 2 for the treatment of persistent organic pollutants in secondary treated municipal wastewater (the physicochemical characteristics of the tested wastewater: pH: 7.8 ± 0.6, COD: 43 ± 24, BOD: 4–26), which was able to achieve 100% COD removal and complete inactivation of pathogens within 10 minutes. However, disadvantages such as high chemical consumption, narrow pH range and the large amount of iron sludge produced limit the development.…”