Fig. 2 and it clearly indicates that PAC is even able to remove HA at low dosage.
The removal ratio was maintained more than 95% when the PAC
dosage was more than 20 mg/L. This removal ratio is higher than
the case of using NaOH as an alkaline chemical. Since CaCO3
behaves as a coagulant reagent, the sedimentation velocity was
significantly high and the SV was reduced about half compared
with the case of using NaOH as a neutralizer.