Microalgae cultivation for the treatment of anaerobically digested municipal centrate (ADMC) and anaerobically digested abattoir effluent (ADAE)

Ashiwin Vadiveloo; Louise Foster; Cherono Kwambai; Parisa A Bahri; Navid R Moheimani

doi:10.1016/j.scitotenv.2021.145853

Microalgae cultivation for the treatment of anaerobically digested municipal centrate (ADMC) and anaerobically digested abattoir effluent (ADAE)

Sci Total Environ. 2021 Jun 25:775:145853. doi: 10.1016/j.scitotenv.2021.145853. Epub 2021 Feb 14.

Authors

Ashiwin Vadiveloo¹, Louise Foster², Cherono Kwambai², Parisa A Bahri³, Navid R Moheimani⁴

Affiliations

¹ Algae R & D Centre, Environmental and Conservation Sciences, College of Science, Health, Engineering and Education School, Murdoch University, 90 South Street, Murdoch, WA 6150, Australia; Centre of Water, Energy, Waste, Harry Butler Institute, Murdoch University, Murdoch, WA 6150, Australia.
² Algae R & D Centre, Environmental and Conservation Sciences, College of Science, Health, Engineering and Education School, Murdoch University, 90 South Street, Murdoch, WA 6150, Australia.
³ Engineering and Energy, College of Science, Health, Engineering and Education, Murdoch University, 90 South Street, Murdoch, WA 6150, Australia.
⁴ Algae R & D Centre, Environmental and Conservation Sciences, College of Science, Health, Engineering and Education School, Murdoch University, 90 South Street, Murdoch, WA 6150, Australia; Centre of Water, Energy, Waste, Harry Butler Institute, Murdoch University, Murdoch, WA 6150, Australia. Electronic address: n.moheimani@murdoch.edu.au.

PMID: 33621869
DOI: 10.1016/j.scitotenv.2021.145853

Abstract

The successful cultivation of microalgae in wastewater establishes a waste to profit scenario as it combines treatment of a waste stream with production of valuable end-products. Here, growth and nutrient removal efficiency of three different locally isolated microalgal cultures (Chlorella sp., Scenedesmus sp., and a mixed consortium) cultivated in anaerobically digested municipal centrate (ADMC) and anaerobically digested abattoir effluent (ADAE) was evaluated. No significant differences (P > 0.05) in specific growth rate and biomass productivity were recorded between Chlorella monocultures and the mixed culture grown in both effluents. Scenedesmus sp. monocultures was found incapable of growth in both ADMC and ADAE throughout the cultivation period resulting in the collapse of cultures and no further measurements on the growth, biomass production and nutrient removal efficiency of this alga in both effluent. F_q´/F_m´ values which represent the immediate photo-physiological status of microalgae found to be negatively inhibited when Scenedesmus sp. was grown in both effluents throughout the cultivation period. F_q´/F_m´ values of Chlorella sp. monocultures and the mixed cultures recovered back to normal (≈0.6) after an initial drop. Ammonium removal rates was found to be significantly higher (≈2 folds) for Chlorella sp. monocultures grown in both ADMC and ADAE when compared to the mixed cultures. Nonetheless, no significant differences were observed in the removal of phosphate for both cultures in the different effluents. The total protein and carbohydrate content of the biomass produced was similar for both microalgae cultures grown using ADAE and ADMC. However, chlorophyll a and total carotenoids content were found to be higher (P < 0.05) for the cultures grown in ADAE than ADMC. Overall, Chlorella sp. monoculture was the most efficient option for treating both ADMC and ADAE while simultaneously generating protein rich biomass (up to 49%) that can be potentially exploited as aquaculture feedstock.

Keywords: Abattoir; Anaerobic; Chlorella sp.; Municipal; Scenedesmus sp.; Wastewater treatment.

MeSH terms

Abattoirs
Biomass
Chlorella*
Chlorophyll A
Microalgae*
Nitrogen
Scenedesmus*
Wastewater

Substances

Waste Water
Nitrogen
Chlorophyll A