Research On The Removal Of Heterosigma Akashiwo(Hada) By The PISC Coagulant

Heterosigma akashiwo(Hada) is one of the toxic algae in China, and blooms caused by this species have been frequently recorded. PISC is one of the effective coagulants, and has been successfully applied in wastewater treatment. PISC has been identified in this study to test effectiveness in removal of Heterosigma akashiwo.Heterosigma akashiwo was kept in laboratory with batch culture. The growth cycle of Heterosigma akashiwo took about 30-40 days in batch culture.To investigate the relationship between optical density (OD) and the cell density, H. akashiwo was cultured and cell density and its related OD was measured. The regression analysis revealed the liner function: N(×10~4 个/ml)=338.9OD-0.8024, (R=0.9976). OD value could be adopted to estimate the biomass of Heterosigma akashiwo.In the experiment of removal Of Heterosigma akashiwo by the PISC, The results showed that PISC had good efficiencies to removal Heterosigma akashiwo at different growth phase. The best dosage at logarithmic phase, stationary phase, decline phase were 1.6ml/L, 1.8ml/L, 1.8ml/L respectively. The best removal phase at the stationary phase of Heterosigma akashiwo. The maximum removal efficiency was recorded at the stationary phase and the value was 94.9 %. Better removal efficiencies, with less dosage applied, have been recorded when PISC and...