Biogas produced from microalgae and sunlight
Anaerobic digestion, whereby microorganisms breakdown organic material in the absence of oxygen, can be used to recover valuable products from waste. These include energy, which can be retrieved in the form of biogas, as well as nutrients and water. The EU-funded project ALGAENET (Renewable energy production through microalgae cultivation: Closing material cycles) project comprised Chilean and European educational and research institutions who investigated the use of sunlight to enhance biogas production from anaerobic digestion processes. Sunlight was used to produce microalgae, which was fed into an anaerobic bioreactor. The bioreactor then converted the algal biomass into biogas, which can be used for energy production. Released carbon dioxide was used for microalgae production as were the nutrients released during anaerobic conversion of the microalgae. A multidisciplinary approach was required to develop the process as two different sub-processes are involved. The first process involved the cultivation and harvesting of microalgae, whereas the second involved the production of biogas and hydrogen. Project partners included experts in algae cultivation, anaerobic digestion for methane and hydrogen production, and modelling and control of bioprocesses. The make-up of the consortium also facilitated the transfer of knowledge between Chile and Europe, including the exchange of researchers between groups thereby opening many possibilities for future work.
Keywords
Microalgae, anaerobic digestion, ALGAENET, bioreactor, Chile
