Co-digestion of microalgae with potato processing waste and glycerol: effect of glycerol addition on methane production and the microbial community

Zhang, Yanghanzi, Caldwell, Gary S., Blythe, Philip T., Zealand, Andrew M., Li, Shuo, Edwards, Simon, Xing, Jin, Goodman, Paul, Whitworth, Paul and Sallis, Paul J. (2020) Co-digestion of microalgae with potato processing waste and glycerol: effect of glycerol addition on methane production and the microbial community. RSC Advances, 10 (61). pp. 37391-37408. ISSN 2046-2069

d0ra07840a.pdf - Published Version
Available under License Creative Commons Attribution.

Download (2MB) | Preview
Official URL:


The production of methane-rich biogas from the anaerobic digestion (AD) of microalgae is limited by an unfavorable biomass carbon-to-nitrogen (C/N) ratio; however, this may be ameliorated using a co-digestion strategy with carbon-rich feedstocks. For reliable plant operation, and to improve the economics of the process, secure co-feedstock supply (ideally as a waste-stream) is important. To this end, this study investigated the feasibility of co-digesting microalgae (Chlorella vulgaris) with potato processing waste (potato discarded parts, PPWdp; potato peel, PPWp) and glycerol, while monitoring the response of the methanogenic community. In this semi-continuous study, glycerol (1 and 2% v/v) added to mixtures of C. vulgaris : PPWdp enhanced the specific methane yields the most, by 53–128%, whilst co-digestion with mixtures of C. vulgaris : PPWp enhanced the methane yields by 62–74%. The microbial communities diverged markedly over operational time, and to a lesser extent in response to glycerol addition. The acetoclast Methanosaeta was abundant in all treatments but was replaced by Methanosarcina in the potato peel with glycerol treatment due to volatile fatty acid (VFA) accumulation. Our findings demonstrate that the performance of microalgae co-digestion is substantially improved by the addition of glycerol as an additional co-feedstock. This should improve the economic case for anaerobically digesting microalgae as part of wastewater treatment processes and/or the terminal step of a microalgae biorefinery.

Item Type: Article
Additional Information: Funding information: This study is part of a PhD at Newcastle University. The authors also gratefully acknowledge the on-going support of the UK's Engineering and Physical Sciences Research Council (EPSRC) through the following funding awards: LC TRANSFORMS (Low Carbon Transitions of Fleet Operations in Metropolitan Sites EP/N010612/1); and CESI (Centre for Energy Systems Integration EP/P001173/1).
Subjects: F100 Chemistry
Department: Faculties > Health and Life Sciences > Applied Sciences
Depositing User: Elena Carlaw
Date Deposited: 26 Jul 2022 08:18
Last Modified: 26 Jul 2022 08:30

Actions (login required)

View Item View Item


Downloads per month over past year

View more statistics