Harvesting of Microalgae Dunaliella salina Using Electroflocculation

Abstract

One of the important bottle-necks in production of microalgae based biodiesel is the lack of an efficient method for harvesting of micro algae from the culture medium. In this study, the electroflocculation method was developed for harvesting of microalgae Dunaliella cells from culture medium. The effect of several p arameters such as the current density, electrical conductivity of culture medium, time, electrode gap, and electrode type on harvesting efficiency and energy consumption were also determined. The maximum harvesting efficiency of this method wa s 97.44% at EC= 1.35 S m -1 and current density of 90 A m -2 during 3 minutes electroflocculation process in a 300 ml beaker. The maximum efficiency was achieved by alum inum electrodes with 1 cm distance between electrodes and the maximum energy consumption for this practice was 0.621 kW h m -3 . It was concluded that electroflocculation is an e fficient and cost effective method for microalgae harvesting. Keywords: Biodiesel, Cell coagulation, Dewatering, Harvestin g Efficiency, Microalgae harvesting.