A Review of Microalgae Harvesting TECHNOLOGY for Biofuel Production

Microalgae are receiving increasing attention worldwide as an alternative and renewable source for energy production. Through various conversion processes, microalgae can be used to produce many different kinds of biofuel, which include biodiesel, bio-syngas, bio-oil, bio-ethanol, and bio-hydrogen. However, large scale production of microalgal biofuel, via many available conversion techniques, faces a number of technical challenges which have made the current growth and development of the algal biofuel industry economically nonviable. Many researchers consider efficient harvesting is the major challenge for commercializing micro-algal biofuel. Algae can be harvested by a number of methods; sedimentation, filtration flocculation, flotation, centrifugation and or a combination of any of these. This review aims at collating and presenting an overview of current harvesting technologies from microalgae for the production of biofuel. Electro-Coagulation Flocculation (ECF) is seen as a promising approach for reducing the cost and energy input of microalgae harvesting for biofuel. However, choosing a harvesting method needed to be considered with a microalgal strain in combination with a considerable influence on the design and operation of both upstream and downstream processes is an overall microalgal biofuel production process