Biofuel from wastewater-grown microalgae: A biorefinery approach using hydrothermal liquefaction and catalyst upgrading.

Third-generation biofuels from microalgae are becoming necessary for sustainable energy. In this context, this study explores the hydrothermal liquefaction (HTL) of microalgae biomass grown in wastewater, consisting of 30% Chlorella vulgaris, 69% Tetradesmus obliquus, and 1% cyanobacteria Limnothrix planctonica, and the subsequent upgrading of the produced bio-oil. The novelty of the work lies in integrating microalgae cultivation in wastewater with HTL in a biorefinery approach, enhanced using a catalyst to upgrade the bio-oil.

Combining urban wastewater treatment with biohydrogen production--an integrated microalgae-based approach.

The aim of the present work was the simultaneous treatment of urban wastewater using microalgae and the energetic valorization of the obtained biomass. Chlorella vulgaris (Cv), Scenedesmus obliquus (Sc) and a naturally occurring algal Consortium C (ConsC) were grown in an urban wastewater. The nutrient removals were quite high and the treated water fits the legislation (PT Dec-Lei 236/98) in what concerns the parameters analysed (N, P, COD).

A biorefinery from Nannochloropsis sp. microalga - energy and CO2 emission and economic analyses.

Are microalgae a potential energy source for biofuel production? This paper presents the laboratory results from a Nannochloropsis sp. microalga biorefinery for the production of oil, high-value pigments, and biohydrogen (bioH2). The energy consumption and CO2 emissions involved in the whole process (microalgae cultivation, harvest, dewater, mill, extraction and leftover biomass fermentation) were evaluated.