EFISIENSI PEMISAHAN MIKROALGA DARI MEDIA TUMBUH LIMBAH CAIR AGROINDUSTRI DENGAN MENGGUNAKAN KOAGULASI/FLOKULASI

Abstract

Microalgae harvesting is a crucial factor in algal production because it influences the production cost. This work evaluated the efficiency of microalgae separation from agroindustrial wastewater by chemical coagulation/flocculation. The efficiency of alumuniumtrisulphate (alum) and polyaluminiumchloride (PAC) applications for coagulation/flocculation process was evaluated in a series of jar test for separation of microalgae in artificial and slaughterhouse wastewater. The xperimental results showed that microalgae could be separated efficiently from the wastewater by flocculation/coagulation method. The separation efficiency depended on the type and dose of coagulant and characteristics, where microalgae was grown. Dosing of approximately 400 g/L alum or 200 mg/L PAC resulted in optimum separation of microalgae in slaughterhouse wastewater, whereas separation of microalgae in the artificial wastewater required relatively higher alum dose of 600 mg/L, or PAC dose of 400 mg/L. Turbidity, color, and total suspended solids values in the effluent were very low. This lead to the possibility of effluent recycling for reuse.