Biogas production coupled to repeat microalgae cultivation using a closed nutrient loop

Lina María González-González; Lihong Zhou; Sergi Astals; Skye R Thomas-Hall; Eladl Eltanahy; Steven Pratt; Paul D Jensen; Peer M Schenk

doi:10.1016/j.biortech.2018.05.039

Biogas production coupled to repeat microalgae cultivation using a closed nutrient loop

Bioresour Technol. 2018 Sep:263:625-630. doi: 10.1016/j.biortech.2018.05.039. Epub 2018 May 22.

Authors

Lina María González-González¹, Lihong Zhou², Sergi Astals³, Skye R Thomas-Hall¹, Eladl Eltanahy⁴, Steven Pratt⁵, Paul D Jensen³, Peer M Schenk⁶

Affiliations

¹ Algae Biotechnology Laboratory, School of Agriculture and Food Sciences, The University of Queensland, Brisbane, Queensland 4072, Australia.
² Algae Biotechnology Laboratory, School of Agriculture and Food Sciences, The University of Queensland, Brisbane, Queensland 4072, Australia; Fisheries College, Jimei University, Xiamen City, Fujian Province, China.
³ Advanced Water Management Centre, The University of Queensland, Brisbane, Queensland 4072, Australia.
⁴ Algae Biotechnology Laboratory, School of Agriculture and Food Sciences, The University of Queensland, Brisbane, Queensland 4072, Australia; Physcology Laboratory, Botany Department, Faculty of Science, Mansoura University, Egypt.
⁵ School of Chemical Engineering, The University of Queensland, Brisbane, Queensland 4072, Australia.
⁶ Algae Biotechnology Laboratory, School of Agriculture and Food Sciences, The University of Queensland, Brisbane, Queensland 4072, Australia. Electronic address: p.schenk@uq.edu.au.

PMID: 29800924
DOI: 10.1016/j.biortech.2018.05.039

Abstract

Anaerobic digestion is an established technology to produce renewable energy as methane-rich biogas for which microalgae are a suitable substrate. Besides biogas production, anaerobic digestion of microalgae generates an effluent rich in nutrients, so-called digestate, that can be used as a growth medium for microalgal cultures, with the potential for a closed nutrient loop and sustainable bioenergy facility. In this study, the methane potential and nutrient mobilization of the microalga Scenedemus dimorphus was evaluated under continuous conditions. The suitability of using the digestate as culture medium was also evaluated. The results show that S. dimorphus is a suitable substrate for anaerobic digestion with an average methane yield of 199 mL g^-1 VS. The low level of phosphorus in digestate did not limit algae growth when used as culture medium. The potential of liquid digestate as a superior culture medium rather than inorganic medium was demonstrated.

Keywords: Anaerobic digestion; Biorefinery; Microalgae; Microalgal cultivation; Nutrient recycling.

MeSH terms

Anaerobiosis
Biofuels*
Methane
Microalgae*
Phosphorus

Substances

Biofuels
Phosphorus
Methane