Pilot-Scale Investigation of Using Ozone-Based Advanced Oxidation for the Removal of Anionic Surfactants from Nuclear Power Plant Wastewater

The presence of surfactants in wastewater poses significant environmental and technological challenges due to their persistence, toxicity, and interference with treatment processes. This study investigates an advanced oxidation process (AOP) for the effective removal of anionic surfactants from radioactive wastewater without generating secondary waste. A pilot-scale system combining ozone (O3), hydrogen peroxide (H2O2), and ultraviolet (UV) radiation was developed and tested using real wastewater from the Ignalina nuclear power plant. Key engineering improvements compared with the existing research included O3 generation from oxygen to increase O3 dissolution efficiency and the use of a Venturi injector to enhance gas‑to‑liquid mass‑transfer efficiency and surfactant removal efficiency. Experimental results demonstrated that the combined O3/H2O2/UV system achieved up to 97% removal efficiency, reducing surfactant concentrations from 3–4 mg/l to about 0.1–0.15 mg/l, meeting operational requirements. Comparable performance was observed using the two-component O3/H2O2 system, indicating that UV radiation is not always necessary to achieve target levels. In contrast, O3 alone or in combination with UV showed significantly lower efficiencies. The findings confirm that ozone-based AOP, particularly O3/H2O2, is a highly effective and environmentally sustainable solution for surfactant degradation in wastewater. This offers broad applicability across various industrial sectors.