3.2. Effect of coagulation/flocculation on flocculation efficiency of C. vulgaris
For the coagulating agent, i.e., ferric chloride, the highest efficiency over 5 min of sedimentation was more than 60% achieved at 500 mg/l concentration (Fig. 3a). However, note that this is a very high concentration, so it may have unfavorable effects on subsequent biomass processing. Further increase of the above-given coagulating agent concentration did not result in higher flocculation efficiency.