The most common of these are compounds based on aluminum
and ferric salts, and polymer-based flocculants. Metal salts were
successfully used for microalgae sedimentation (in particular,
Dunaliella (Ben-Amotz and Avron, 1990), Microcystis sp.
(El-Diwani et al., 2011)), but their use would lead to undesired high
concentrations of metals in the sediment (Rwehumbiza et al.,
2012).