title: Evaluation of microalgae production coupled with wastewater treatment.
abstract: In the present study, the feasibility of microalgae production coupled with wastewater treatment was assessed. Continuous cultivation of Chlorella sorokiniana with wastewater was tested in lab-scale flat-panel photobioreactors. Nitrogen and phosphorus removals were found to be inversely proportional to the four dilution rates, while chemical oxygen demand removal was found to be 50% at all the tested conditions. The biomass obtained at the highest dilution rate was characterized for its content of lipids, proteins and pigments. The average yields of fatty acid methyl esters (FAMEs), protein, lutein, chlorophylls and β-carotene was 62.4, 388.2, 1.03, 11.82 and 0.44 mg per gram dry biomass, respectively. Economic analysis revealed that potentially more than 70% of revenue was from the production of pigments, that is, chlorophyllin (59.6%), lutein (8.9%) and β-carotene (5.0%) while reduction in discharging costs of the treated wastewaters could account for 19.6% of the revenue. Due to the low market price of biodiesel, the revenue from the above was found to be the least profitable (1.4%). Even when combining all these different revenues, this cultivation strategy was found with the current prices to be uneconomical. Power consumption for artificial light was responsible for the 94.5% of the production costs.
authors.affiliation: a Department of Environmental Engineering , Technical University of Denmark , Kgs. Lyngby , Denmark.
authors.forename: Davide
authors.initials: D
authors.lastname: De Francisci
authors.affiliation: a Department of Environmental Engineering , Technical University of Denmark , Kgs. Lyngby , Denmark.
authors.forename: Yixi
authors.initials: Y
authors.lastname: Su
authors.affiliation: b Department of Environmental Engineering , Tallinn University of Technology , Tallinn , Estonia.
authors.forename: Arvo
authors.initials: A
authors.lastname: Iital
authors.affiliation: a Department of Environmental Engineering , Technical University of Denmark , Kgs. Lyngby , Denmark.
authors.forename: Irini
authors.identifier: http://orcid.org/0000-0002-6357-578X
authors.initials: I
authors.lastname: Angelidaki
mesh_terms: D057919:Biological Oxygen Demand Analysis; D002708:Chlorella / Q000378:metabolism; D058086:Microalgae / Q000378:metabolism; D009584:Nitrogen / Q000032:analysis; D010758:Phosphorus / Q000032:analysis; D058433:Photobioreactors; D014865:Waste Disposal, Fluid / Q000379:methods*; D062065:Wastewater; D014874:Water Pollutants, Chemical / Q000032:analysis
chemical_list: D009584:Nitrogen; D010758:Phosphorus; D062065:Wastewater; D014874:Water Pollutants, Chemical
keywords: Chlorella sorokiniana; biorefinery; economic analysis; photobioreactors; wastewaters