Effect of Growth Phase on the Flocculation of Algal Cells Using Clays
藻细胞不同生长阶段的海泡石凝聚除藻性能

Four different growth phases, late lag phase, middle logarithmic phase, late logarithmic phase and early senescence phase of Microcystis aeruginosa 469 were studied for their surface hydrophobicity (xylene-water system) and surface charge (Zeta potential), followed by flocculation tests with sepiolite of 0.2 g/L. The results showed that the values of hydrophobicity were 64%, 48%, 58% and 70%, and the algal removal efficiencies after 60 min were 97%, 87%, 81% and 99% respectively, indicating a good relationship between surface hydrophobicity and removal efficiency (R = 0.7-0.8), but not the surface charge. Surface hydrophobicity and removal efficiency for the algal cells of Microcystis aeruginosa both varied with growth phase in a sequence of senescence phase > lag phase > logarithmic phase.