Exploring the potential of microalgae for bioenergy production

Abstract

Initially flocculation with chitosan to harvest algal biomass of the green alga Chlorella sorokinianawas explored. Chitosan proved to be highly efficient in the induction of flocculation with the clarification efficiency reaching >99% below pH 7 at optimal dosage. Influencing factors of flocculation efficiency and its effect on the subsequent dewatering process were also evaluated.It was shown to reduce the volume to be processed by 20–50 folds, and significantlyreduce energy input and material costs of centrifugation or filtration operations.In order to reduce the complicated and costly downstream processes of algal biofuel production, this work explores an alternative way of utilizing energy from algal cells by blending algal slurry into fossil diesel using specific combinations of surfactants. We will show that this approach provides benefits by reducing the consumption of fossil fuel; improving the engine combustion performance; and reducing exhaust emissions particularly NOx thus benefiting the environment.