Chlorella vulgaris as a green biofuel factory: Comparison between biodiesel, biogas and combustible biomass production. (February 2019)

• Record Type: Journal Article
• Authors: Sakarika, Myrsini; Kornaros, Michael
• Is Part Of: Bioresource technology. Volume 273(2019)
• Page Start: 237
• Page End: 243
• Publication Date: 2019-02
• Subjects: Biofuels -- Microalgal biomass -- Biomethane -- Biodiesel -- Calorific value -- Sustainability; Biomass -- Periodicals; Biomass energy -- Periodicals; Bioremediation -- Periodicals; Agricultural wastes -- Periodicals; Factory and trade waste -- Periodicals; Organic wastes -- Periodicals; Bioénergie -- Périodiques; Déchets agricoles -- Périodiques; Déchets industriels -- Périodiques; Déchets organiques -- Périodiques; Déchets (Combustible) -- Périodiques; 662.88
• DOI: 10.1016/j.biortech.2018.11.017
• Languages: English
• ISSNs: 0960-8524

Abstract

Highlights: The calorific value of dry C. vulgaris biomass is 24, 538 ± 182 kJ kg −1 . Anaerobic digestion is the most promising energy valorization method of C. vulgaris . Lipid productivity of 442.9 ± 6.5 mg L −1 d −1 can be achieved under sulfur limitation. Mesophilic anaerobic digestion resulted in 360.95 ± 20.17 mL CH4 g VS −1 added . Thermophilic anaerobic digestion is unsuitable for this type of substrate. Abstract: Biofuels are viewed as the answer to safeguard the currently challenged energy security. To this end, the present study provides a comparison between approaches regarding microalgal biomass conversion to bioenergy, with a view on sustainable implementation. The energetic valorization of Chlorella vulgaris biomass cultivated under heterotrophic, sulfur-limited conditions was investigated through the biofuels biodiesel, biogas (biomethane) and combustible dry biomass. The lipid productivity can reach the value of 442.9 ± 6.5 mg L −1 d −1 containing suitable fatty acids for biodiesel production. Next, biochemical methane potential (BMP) assays yielded 360.9 ± 20.2 mL CH4 g VS −1 added under mesophilic conditions, while the calorific value of dry C. vulgaris biomass was measured as 24, 538 ± 182 kJ kgDW −1 (5, 865 ± 43 kcal kgDW −1 ). Considering the downstream processing required in each approach, the most promising energy valorization method is anaerobic digestion able to reach values up to 20, 862 kJ Lreactor −1 day −1 in continuous systems.