Wastewater treatment with algal based culture and biofuel production from algal biomass

This research topic combines wastewater treatment and bioenergy production (energy from wastewater). Wastewater treatment occurs by means of algae biomass which is subsequently harvested for biogas generation in anaerobic digesters.

Microalgae grow by assimilation of inorganic carbon generated through heterotrophic degradation of organic matter in wastewater, carried out by bacteria using oxygen released through algal photosynthesis.

The anaerobic digestion of microalgae to produce biogas is a way of recovering the energy contained in wastewater. Biofuel generation from microalgae grown in wastewater is more sustainable since algae can uptake nutrients from wastewater, avoiding fertilizers and water consumption. Besides, the high lipids content of microalgae can improve the methane production compared to conventional sludge digestion.

Biofuel generation in this type of system can reduce greenhouse gas emissions from conventional fossil fuel combustion. The bottle neck of this approach is biomass harvesting from the mixed liquor and the hydrolysis of microalgae cell walls, which require further investigation.

Our research is focused on the cultivation of microalgae in experimental high rate algal ponds and photobioreactors, biomass harvesting and anaerobic digestion to produce biogas.