Biodiesel from Microalgae

Widespread application of non-renewable energy resources such as fossil fuels is limited mainly due to their adverse environmental impacts by increasing the amount of greenhouse gas (GHG) emissions. A solution to limit fossil-fuel pollution is the use of renewable energy resources. In the recent years, microalgae have received considerable attention as a suitable feedstock for biofuel production. Microalgae can grow in various aquatic wastewater media and are able to produce biomass, lipids, and hydrocarbons. Using different types of wastewaters as media for algae cultivation could not only reduce their freshwater footprint but also the costs associated with algae cultivation and biofuel production. This chapter presents an overview on various algal cultivation systems as well as on optimization of algal cultivations, while downstream processes including harvesting and drying of microalgae and lipid extraction systems are also reviewed and discussed. Subsequently, different microalgae biofuel production pathways are presented. Finally, the applications of microalgae in integrated systems, i. e., in wastewater treatment and biodiesel production systems and biofixation of carbon, are scrutinized.