Inactivation effect and mechanism of algae in simulated ballast water by DSA electrocatalysis

Managing biological contaminants in ship ballast water is crucial for maritime nations to mitigate ecological and health risks. This study investigated the efficiency of algae inactivation in simulate ballast water using a dimensionally stable anode (DSA) electrocatalysis system. The findings showed that the inactivation rate varied depending on the algal species and could be optimized by adjusting hydraulic retention time (HTR), current density, and electrode surface area. Furthermore, the DSA electrocatalysis system provided a significantly sustained inactivation effect on algae in the holding time after electrolytic operation. The inactivation rates for Platymonas subcordiformis and Heterosigma akashiwo could reach up to 99.27% and 99.09%, respectively. Besides the direct oxidation and reduction of electric field, the reactive oxygen species, such as 𝐶𝑙𝑂 ⁻ ∙𝑂𝐻, ∙𝑂 ₂ ⁻ , whichwere generated during the DSA electrocatalysis process, were primary factors responsible for algae inactivation. The DSA electrocatalysis led to lipid peroxidation in algal cell membranes, causing structural damage and metabolic failure.