Effect of mine wastewater on nutrient removal and lipid production by a green microalga Micratinium reisseri from concentrated municipal wastewater

Abstract

Effect of mine wastewater on the nutrient removal efficiency of a green microalga Micratinium reisseri from concentrated municipal wastewater (CMW) with simultaneous lipid production was investigated. Different dilution ratios (1-10%) of CMW either with mine wastewater (MWF) or mine wastewater without Fe (MWOF) were used. M. reisseri showed the highest growth (0.8 g L (1)) and nutrient uptake (35.9 mg TN L (1) and 5.4 mg TP L (1)) at 3% MWF ([Fe](tot) = 6.7 mg L (1)), and the highest lipid productivity (10.4 mg L (1) day (1)) at 5% MWF ([Fe](tot) = 11.2 mg L (1)) after 15 days. CMW supported the algal autoflocculation due to formation of phosphate, calcium and magnesium precipitates at a high suspension pH. Fatty acid methyl ester analysis revealed that the microalgal lipids possessed 79-82% of C16/C18 fatty acids. Application of mine wastewater improved the nutrient removal efficiency, growth and lipid productivity of M. reisseri cultivated in CMW. (C) 2014 Elsevier Ltd. All rights reserved.