Use of microalgae to recycle nutrients in aqueous phase derived from hydrothermal liquefaction process

Abstract

Hydrothermal liquefaction (HTL) of microalgae biomass generates an aqueous phase (AP) byproduct with limited energy value. Recycling the AP solution as a source of nutrients for microalgae cultivation provides an opportunity for a cost-effective production of HTL based biofuel and algal biomass feedstock for HTL, allowing a closed-loop biofuel production in microalgae HTL biofuel system. This paper aims to provide a comprehensive overview of characteristics of AP and its nutrients recycling for algae production. Inhibitory effects resulted from the toxic compounds in AP and alleviation strategies are discussed.

Keywords: Algae cultivation; Aqueous phase; Hydrothermal liquefaction; Inhibitory effect; Microalgae; Nutrient recycle.