Study on emergency algae removal under high flux in an ultrafiltration waterplant

To solve the ultrafiltration water plant´s contradiction of high flux and membrane fouling in summer when algae was high, and ensure the water plant security and stable, a pilot testing which using immersion membrane as the core of combined process was carried on. The results showed: preoxidation using potassium permanganat and coagulation could efficiently reduce the number of algae, ultrafiltration could totally remove algae cells. Appropriate amount of potassium permanganate dosage could reduce the transmembrane pressure, while exorbitant dosage made organic matter variety which increased membrane fouling, the best amount of potassium permanganate was 1.0mg/L. Increasing the frequency of membrane surface´s air impact was able to enhance the stable operating flux by 20% while didn´t affect the water producing rate. Combined emergency process would not lead to significant increase in water plant operation costs.