Applicability of advanced oxidation processes for the reuse of laundry wastewater

The integration of advanced oxidation processes (AOPs) for the treatment of laundry wastewater could significantly improve resource efficiency and reduce overall freshwater consumption, thus contributing to sustainable water management strategies. This study therefore demonstrated the effectiveness of different AOPs including O₃, H₂O₂, O₃/H₂O₂, O₃/UV-C, H₂O₂/UV-C, and O₃/H₂O₂/UV-C in the treatment of laundry wastewater to determine the most efficient AOP based on the removal of chemical oxygen demand (COD) and methylene blue active substances (MBAS). The results showed that the O₃/H₂O₂/UV-C method had the highest removal efficiency for both COD (83%) and MBAS (96%). Additionally, a significant reduction in microbial growth was observed in the treated wastewater compared to untreated raw wastewater. Textile tests with the treated wastewater confirmed its potential for reuse in washing machines, as evidenced by achieving a gray scale number of 5, the highest possible without dyeing. These results are further proof of the feasibility of in-situ treatment for the sustainable reuse of laundry wastewater.