3.3. Effect of ballast agent on flocculation efficiency of C. vulgaris
This study looked into the possibility to add the already flocculated biomass into microalgal culture broth. Thus, the biomasses added were both flocculated by
different flocculants, and those flocculated by coagulant and flocculant mixtures. In one case, it was biomass flocculated by agents that showed their efficiency, in particular, Superfloc C-492, Sibfloc-718 and FeCl3. Also, the experiments used the mixture that also proved to be the most efficient earlier, i.e., Sibfloc-718 and FeCl3.
The highest efficiency was achieved using biomass flocculated by Sibfloc-718 and FeCl3mixture. Note, that the sedimentation efficiency with its addition would reach about 50% and keep at this level for quite a time (Fig. 4a–d). Thus, this method is less effective than the case with Sibfloc-718 and FeCl3 mixture.