Scenedesmus obliquus in poultry wastewater bioremediation

ABSTRACT

Wastewater biological treatment with microalgae can be an effective technology, removing nutrients and other contaminants while reducing chemical oxygen demand. This can be particularly interesting for the meat producing industry which produces large volumes of wastewater from the slaughtering of animals and cleaning of their facilities. The main purpose of this research was the treatment of poultry wastewater using Scenedesmus obliquus in an economical and environmentally sustainable way. Two wastewaters were collected from a Portuguese poultry slaughterhouse (poultry raw – PR and poultry flocculated – PF) and the bioremediation was evaluated. The performance of microalga biomass growth and biochemical composition were assessed for two illumination sources (fluorescent vs LEDs). S. obliquus achieved positive results when grown in highly contaminated agro-industrial wastewater from the poultry industry, independently of the light source. The wastewater bioremediation revealed results higher than 97% for both ammonium and phosphate removal efficiency, for a cultivation time of 13 days. The saponifiable matter obtained from the biomass of the microalga cultures was, on average, 11% and 27% (m/m_alga) with PR and PF wastewater, respectively. In opposition, higher sugar content was obtained from microalgae biomass grown in PR wastewater (average 34% m/m_alga) in comparison to PF wastewater (average 23% m/m_alga), independently of the illumination source. Therefore, biomass obtained with PR wastewater will be more appropriate as a raw material for bioethanol/biohydrogen production (higher sugar content) while biomass produced in PF wastewater will have a similar potential as feedstock for both biodiesel and bioethanol/biohydrogen production (similar lipid and sugar content).

GRAPHICAL ABSTRACT

KEYWORDS:

• Wastewater
• microalga
• Scenedesmus obliquus
• poultry
• bioremediation

Acknowledgments

This study was supported by the project BIOSUSTAIN – PTDC/EMS-ENE/1839/2012 ‘Sustainable mobility: Perspectives for the future of biofuels production’ and COST Action 1408 EUALGAE- European network for algal-bioproducts. The authors would like to acknowledge AVIBOM (Torres Vedras, Portugal) that kindly provided the poultry wastewaters, Graça Gomes and Natércia Santos for the microalgae culture maintenance and laboratory assistance.

Disclosure statement

No potential conflict of interest was reported by the authors.

ORCID

Ana P. Batista http://orcid.org/0000-0001-7366-1254