Sanitation of seawater effluent from seaweed processing plants using a photo-catalytic TiO2 oxidation

A fine porcelain open-cell photo-catalytic filter with titanium dioxide (TiO2) was evaluated for sterilization and sanitation of bio-polluted industrial water. In simulated seawater industrial effluent samples, the populations of Escherichia coli and Vibrio parahaemolyticus quickly decreased and reached non-detectable level within 10 min. In seawater effluents from a seaweed processing plant, the bacterial populations in two samples quickly decreased by more than 103. In another two samples the decreases were slow and lowered by less than 102. Using fluorescence microscopy, it was indicated that the bacterial cells treated with photo-catalytic TiO2 were damaged. In addition, the protein concentration in simulated seawater effluent slowly decreased using the photo-catalytic TiO2 reaction; and reached similar concentrations as seawater near cultured seaweed beds. These results indicate that using a reactor with a TiO2 photo-catalyst filter was effective for the sanitation of seawater effluents.