Bio-fuel from microalgae by using of closed photo-bioreactors 25-34 M. F. Demirbas

Energy Education Science and Technology Part C: Future Energy Sources

2017 Volume (issue) 9(1): 25-34



Bio-fuel from microalgae

by using of closed photo-bioreactors


M. Fatih Demirbas*


Sila Science, Trabzon, Turkey




Received: 26 July 2016; accepted 19 October 2016



     Life in the world began with algae. Algae require carbon dioxide and water to convert the energy of sunlight into chemical energy by photosynthesis. All algae mainly compose of lipids, carbohydrates, proteins and nucleic acids. Algal oil from microalgae is the promising and sustainable feedstock for biodiesel production. Microalgae have also been mainly cultured as food by mankind for centuries.  The industrial size reactors for algal culture are at present. There are (1) photo-bioreactors (PBRs), (2) open pond systems and (3) closed and hybrid systems. Numerous designs of PBR such as tubular, flat-plated, rectangular, continued stirred reactors, etc. have been developed. PBRs include innovative production designs the preferred for scientific researchers. Algae can be harvested by centrifugation, flocculation or froth flotation. Alum and ferric chloride are used as flocculants to harvest algae. Algae harvesting and processing optimization is required such as algae size, cell wall accuracy and strength, algae properties, flocculation ease, and oil content need to be considered in the design process. Microalgae production in closed PBRs is highly expensive. The culture productivity of a PBR depends on both hydrodynamic and geometric parameters. The optimal design and control of PBRs is important to increase yield of algae. The PBRs provide much higher productivity than traditional fast-growing energy crops. Less area required than traditional crops when grown in PBRs. The wastewater quality for algae cultivation of PBR is lower than those of other algae cultivation systems. The PBRs provide to obtain production of economically valuable chemicals.


Keywords: Microalgae; Closed photo-bioreactor (CPBR); Algal oil; Biodiesel