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Microalgae Flocculation
Biotechnology Advances 20 (2003) 491 – 515 www.elsevier.com/locate/biotechadv Recovery of microalgal biomass and metabolites: process options and economics
´ ´ E. Molina Grimaa, E.-H. Belarbia, F.G. Acien Fernandeza, a b,* A. Robles Medina , Yusuf Chisti b ´ ´ Department of Chemical Engineering, University of Almerıa, E-04071 Almerıa, Spain Institute of Technology and Engineering PN456, Massey University, Private Bag 11 222, Palmerston North, New Zealand

a

Received 27 May 2002; received in revised form 15 October 2002; accepted 15 October 2002

Abstract Commercial production of intracellular microalgal metabolites requires the following: (1) largescale monoseptic production of the appropriate microalgal biomass; (2) recovery of the biomass from a relatively dilute broth; (3) extraction of the metabolite from the biomass; and (4) purification of the crude extract. This review examines the options available for recovery of the biomass and the intracellular metabolites from the biomass. Economics of monoseptic production of microalgae in photobioreactors and the downstream recovery of metabolites are discussed using eicosapentaenoic acid (EPA) recovery as a representative case study. D 2002 Elsevier Science Inc. All rights reserved.
Keywords: Microalgae; Phaeodactylum tricornutum; Eicosapentaenoic acid; Process economics; Flocculation; Biomass recovery

1. Introduction Microalgae can be used to produce numerous high-value bioactives (Borowitzka, 1986; Bubrick, 1991; Pulz et al., 2001; Li et al., 2001; Banerjee et al., 2002). Production of
* Corresponding author. Tel.: +64-6-350-5934; fax: +64-6-350-5604. E-mail address: Y.Chisti@massey.ac.nz (Y. Chisti). 0734-9750/02/$ – see front matter D 2002 Elsevier Science Inc. All rights reserved. PII: S 0 7 3 4 - 9 7 5 0 ( 0 2 ) 0 0 0 5 0 - 2

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E. Molina Grima et al. / Biotechnology Advances 20 (2003) 491–515

microalgae-derived metabolites requires processes for culturing the alga (Ben-Amotz and



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