TY - JOUR ID - 59904 TI - Flocculation of Microalgae via pH Change in a Turbulent Medium and Subsequent Filtration JO - International Journal of Environmental Research JA - IJER LA - en SN - 1735-6865 AU - Vera Morales, J. M. AU - Ramirez Romero, L. A. AU - Vanthoor-Koopmans, M. AD - Engineering Faculty, Autonomous University of Querétaro, Querétaro, Mexico AD - Chemistry Faculty, Autonomous University of Querétaro, Querétaro, Mexico Y1 - 2016 PY - 2016 VL - 10 IS - 4 SP - 593 EP - 600 KW - Chlorella vulgaris KW - aggregation KW - harvesting KW - Continuous culture KW - alkaline medium DO - 10.22059/ijer.2016.59904 N2 - Traditional microalgae harvesting techniques consume a lot of energy. Flocculation, or the formation of aggregates, is an energetically favorable process to collect biomass. Flocculation is normally carried in tanks to allow the formation of the aggregates after stirring, however, this consumes time and physical resources. In this work, flocculation of Chlorella vulgaris and Scenedesmus sp. by acidification and alkalization was compared to chemical flocculation in a turbulent medium for short periods of time (30 seconds and 2 minutes). Flocculation with potassium hydroxide at pH=10 showed to be nearly as efficient as traditional flocculation by using ferric sulphatum after two minutes. Acid flocculation with nitric acid was not as effective, even at values of pH=4. Flocculation by pH does not generate toxic wastes and the remaining added flocculants turn into nutrients after harvesting. After flocculation and neutralization, the remaining cells in the medium were viable to recultivate. Since pH-driven flocculation does not allow harvesting the total microalgae culture, remaining cells can be used to keep growing. Based on these results a semi continuous harvesting method incorporated in the microalgae growing phase seems promising. UR - https://ijer.ut.ac.ir/article_59904.html L1 - https://ijer.ut.ac.ir/article_59904_9b5c6b81c2fdef7a198d007445e7b111.pdf ER -