Abstract
•Biofouling in seawater cooling systems depends on feed seawater quality.•Alternative oxidants are studied to control biofouling in the cooling towers.•Effects of oxidant dosage and cycle of concentration are studied.•Chlorine dioxide yields higher disinfection rates even at low oxidant dosage.•Chlorine dioxide performs the best TRO demand compared to chlorine and ozone.
Biofouling can significantly hamper the efficiency of seawater cooling towers. The aim of this study was to investigate the effectiveness of alternative oxidants (i.e. ozone (O3) and chlorine dioxide (ClO2)) comparing with commonly being used chlorine in biofouling control. Effects of cycle of concentration, temperature and oxidant dosage along with residual decay and kinetics were studied. Even at lower oxidant dosage (total residual oxidant equivalent=0.1mg/l Cl2), ClO2 showed a better disinfection effect compared to chlorine and O3. Results of bench-scale studies will be helpful in the selection of appropriate oxidant for seawater cooling tower operation.