Experimental results show that raw water natural organic matter (NOM), coagulant dose and coagulation
pH affected both the rate and potential extent of dewatering. Similar effects were observed for both
aluminium sulfate and ferric chloride. These results suggest that increasing dose orpHleads to an increase
in the proportion of rapidly precipitated material in the sludge or flocs, which form looser aggregates and
hence exhibit inferior dewatering properties.