title: Pretreatment of microalgae to improve biogas production: a review.
abstract: Microalgae have been intensively studied as a source of biomass for replacing conventional fossil fuels in the last decade. The optimization of biomass production, harvesting and downstream processing is necessary for enabling its full-scale application. Regarding biofuels, biogas production is limited by the characteristics of microalgae, in particular the complex cell wall structure of most algae species. Therefore, pretreatment methods have been investigated for microalgae cell wall disruption and biomass solubilization before undergoing anaerobic digestion. This paper summarises the state of the art of different pretreatment techniques used for improving microalgae anaerobic biodegradability. Pretreatments were divided into 4 categories: (i) thermal; (ii) mechanical; (iii) chemical and (iv) biological methods. According to experimental results, all of them are effective at increasing biomass solubilization and methane yield, pretreatment effect being species dependent. Pilot-scale research is still missing and would help evaluating the feasibility of full-scale implementation.
authors.affiliation: GEMMA - Group of Environmental Engineering and Microbiology, Department of Hydraulic, Maritime and Environmental Engineering, Universitat Politècnica de Catalunya·BarcelonaTech, c/Jordi Girona 1-3, Building D1, E-08034 Barcelona, Spain. Electronic address: fabiana.lopes.del.rei@upc.edu.
authors.forename: Fabiana
authors.initials: F
authors.lastname: Passos
authors.affiliation: GEMMA - Group of Environmental Engineering and Microbiology, Department of Hydraulic, Maritime and Environmental Engineering, Universitat Politècnica de Catalunya·BarcelonaTech, c/Jordi Girona 1-3, Building D1, E-08034 Barcelona, Spain. Electronic address: enrica.uggetti@upc.edu.
authors.forename: Enrica
authors.initials: E
authors.lastname: Uggetti
authors.affiliation: INRA, UR0050, Laboratoire de Biotechnologie de l'Environnement, Avenue des Etangs, Narbonne F-11100, France. Electronic address: helene.carrere@supagro.inra.fr.
authors.forename: Hélène
authors.initials: H
authors.lastname: Carrère
authors.affiliation: GEMMA - Group of Environmental Engineering and Microbiology, Department of Hydraulic, Maritime and Environmental Engineering, Universitat Politècnica de Catalunya·BarcelonaTech, c/Jordi Girona 1-3, Building D1, E-08034 Barcelona, Spain. Electronic address: ivet.ferrer@upc.edu.
authors.forename: Ivet
authors.initials: I
authors.lastname: Ferrer
mesh_terms: D056804:Biofuels / Q000382:microbiology*; D019149:Bioreactors / Q000382:microbiology*; D018929:Cell Culture Techniques / Q000379:methods; D003470:Culture Media / Q000737:chemistry* / Q000378:metabolism*; D008697:Methane / Q000302:isolation & purification / Q000378:metabolism*; D058086:Microalgae / Q000737:chemistry* / Q000145:classification / Q000378:metabolism*; D013045:Species Specificity
chemical_list: D056804:Biofuels; D003470:Culture Media; D008697:Methane
keywords: Anaerobic digestion; Bioenergy; Biofuel; Methane; Microalgae