© 2016 Elsevier Ltd. Combined effect of ferric chloride and pH on Chlorella vulgaris growth and flocculation were optimized using DoE. Afterwards, an integrated bioprocess for microalgae cultivation and harvesting conceived as a sole step was run in continuous operation mode. Microalgae concentration in a 2L-photobioreactor was about 0.5 g L-1 and the efficiency of flocculation in the coupled sedimentation tank was about 95%. Dewatered microalgae reached a biomass concentrations increase about 50-fold, whereas it was only about 0.02 g L-1 in the clarified medium. Then, the reuse of the clarified medium recovered was further evaluated. The clarified medium was reused without any further nutrient supplementation, whereas a second round of medium reuse was performed after supplementation of main nutrients (phosphate-sulfate-nitrate), micronutrients and ferric chloride. The medium reuse strategy did not affect cell growth and flocculation. Consequently, the reuse of medium reduces the nutrients requirements and the demand for water, and therefore the production costs should be reduced accordingly.
- Integrated continuous production
- Medium optimization
- Medium reuse
- Microalgae flocculation
- Single step microalgae production