In order to use high-density coagulation sedimentation technology into the pretreatment process of seawater desalination

a pilot test facility has been established

the influence of coagulant dosage

sludge recirculation rate and flow rate upon coagulation effectiveness being investigated

results show that as in the following:when the flow rate was 2 m3/h

the dosage of coagulant was 25 mg/L

the dosage of coaglant was 25 mg/L

the dosage of coagulant aid was 0.15 mg/L

and the sludge recirculation rate was 30%

the average turbidity of effluent water can be reduced to 10 NTU

the turbidity removal rate being more than 94%;increasing the sludge recirculation ratio can evidently decrease the tubidity of effluent water;compared with the micro-whirling coagulation technology

the turbidity of effluent water in high-density coagulation technology was lower

the quality of effluent water was stabler

and the impulse load resistant ability was strong.