FLOCCULATION AND REMOVAL OF MICROCYSTIS AERUGINOSA BY THE NATURAL COAGULANT FROM CITRUS PEEL

The effective removal of harmful cyanobacte-rial is a crucial step for preventing or minimizing these cyanobacteria-derived water quality issues. In the current work, by using water as an extracting agent, the aqueous extract of citrus peel (AECP), as a natural coagulant, was extracted from citrus peel. Laboratory studies have shown that AECPs are effective in the removal of M. aeruginosa. In addition, the influences of the particle size of the citrus peel, the material to solvent ratio, the centrifugal speed, the addition dosage of AECP and the membrane pore size were evaluated in terms of the removal efficiency of M. aeruginosa, and the optimum extracting conditions of the AECP were determined. Under the optimized conditions, the removal rate for M. aeruginosa can reach 93.46%. The results indicated that AECP, when used as a natural coagulant, could be applied to treat harmful cyanobacterial blooms. We also found that the particulate matter in the aqueous extract exerted beneficial effects on coagulation.