Integrated coagulation-ultrafiltration for enhanced removals of phosphate and organic in tertiary treatment

摘要

We have demonstrated an integrated coagulation-ultrafiltration (UF) process for enhanced removals of phosphate and dissolved organic carbon (DOC) in tertiary treatment. A lab scale system with hollow fiber UF membranes was used in the study. Dead-end operation was applied in the study since its advantages of low energy consumption and high water recovery over cross-flow operation. The results showed that removals of phosphate and DOC at alum dosage of 10 mg l~(-1) in the study were ＞99% (or phosphate ＜0.03 mg l~(-1) in product) and 25%, respectively. The coagulation time in the new integrated coagulation-UF process was reduced to 1 min with much less foot-print. The concentration of alum dose could be further optimized between 5 and 10 mg l~(-1).