Biotechnological potential of Phaeodactylum tricornutum for biorefinery processes

Microalgae are a rich source of proteins, carbohydrates and lipids, among other components, and thus, are considered to be the next generation biomass. However, in order to enhance the economic viability of its industrial production, all biomass components need to be valorized, requiring a multi-product biorefinery. Thus, this work proposes and conceptually analyses biorefinery processes for valorizing Phaeodactylum tricornutum for biofuels and high-value compounds, based on real data from a pilot-scale process. The algal biomass was biochemically characterized and the production was scaled-up to an industrial approach to analyze three biorefinery configurations, based on a 18 ton.year(-1) of microalga biomass. The biomass revealed a composition of 7.85 wt% carbohydrates, 38.40 wt% proteins, 9.08 wt% lipids, 0.86 wt% fucoxanthin and 5.19 wt% biosilica. The biorefinery process addressed for biofuels production has an estimated annual production of 1.72, 0.35 and 1361 m(3).year(-1) of respectively biodiesel, bioethanol and biomethane. The biorefinery addressed for high-value compounds yields 0.18, 0.93 and 6.95 ton.year(-1) of respectively fucoxanthin, biosilica and protein. The biorefinery designed for valorizing full microalgae biomass, showed to be more beneficial for promoting a circular economy. Biorefinery approach is useful for making sound and profitable decisions regarding microalgae bioproducts.