Energy and Nutrients Recovery from Lipid-Extracted Nannochloropsis via Anaerobic Digestion and Hydrothermal Liquefaction

Identifier:  imarina:6388710

Handle: https://hdl.handle.net/20.500.11797/imarina6388710

Authors:  Caporgno, MP; Clavero, E; Torras, C; Salvadó, J; Lepine, O; Pruvost, J; Legrand, J; Giralt, J; Bengoa, C

Abstract:
© 2016 American Chemical Society. The biomass, generated after the lipid extraction from Nannochloropsis microalgae (LEM) for biodiesel production, demonstrated its suitability for both energy and nutrient recovery. The anaerobic digestion of LEM produced a minimum of 268 mLCH4/gVS in different experiments. The codigestion of LEM and sewage sludge revealed that both wastes can be codigested without inhibition, although no synergy was observed. The methane yields barely increased 10% after pretreatments (ultrasound and ultrasound combined with alkali addition). Regarding bio-oil production from hydrothermal liquefaction process, more than 28% of the LEM was converted into bio-oil. Moreover, the aqueous phase generated during the bio-oil production was successfully utilized as nitrogen source for microalgae cultivation.