Enhanced Coagulation To The Algae

This dissertation is designed to study the technique of intensified coagulation in eutrofication water resources. This dissertation investigates the technical parameters of intensified coagulation in algae removal in the following processes: polyaluminum chloride(PAC), combination of PAC and natural mineral coagulant aid, self-made modified polyaluminum ferric chloride(PAFC) and combination of polyaluminum silicon chloride(PASC) and natural mineral coagulant aid, KFeO4 pre-oxidation and combination of coagulant aid and coagulant.The experiment shows that the optimum dosage is 40mg/L, the removal rent of the turbidity, chlorophyll a, permanganate is 63.2%, 44.3% and 35.3%. When PAC and natural mineral coagulant aid A is best complex used, the removal rent of turbidity, chlorophyll a, permanganate is 94.7%, 69.1% and 59.9%, but floe volume decreases 50%. When Al/Fe is 9:1 and basicity is 1.8, the flocculation removal effect of alga by Self-made PAFC is the best. When the combination of 5x10~4mol/L PAFC and 40mg/L coagulant aid, the removal effect of turbidity, chlorophyll a, permanganate is the best and is 94.0%, 75.3% and 64.0%. when Al/Fe is 9:1 and basicity is 1.8, The flocculation removal effect of alga by Self-made PASC is the best. When the combination of 5X10 4mol/L PASC and 40mg/L coagulant aid, the removal effect of turbidity U, chlorophyll a, permanganate is the best and is 96.4%, 77.8% and 67.5%.The optimum dosage of combination of KFeO4 and coagulant aid, flocculation, the removal effect of turbidity, chlorophyll a, permanganate is 96.7%, 84.0% and 70.4%. At last, comparing the effect in coagulating algae removal and economy of usage, it gives the best method of coagulating algae removal.