The effect of augmentation of biochar and hydrochar in anaerobic digestion of a model substrate

Jessica Quintana-Najera; A John Blacker; Louise A Fletcher; Andrew B Ross

doi:10.1016/j.biortech.2020.124494

The effect of augmentation of biochar and hydrochar in anaerobic digestion of a model substrate

Bioresour Technol. 2021 Feb:321:124494. doi: 10.1016/j.biortech.2020.124494. Epub 2020 Dec 3.

Authors

Jessica Quintana-Najera¹, A John Blacker², Louise A Fletcher³, Andrew B Ross⁴

Affiliations

¹ School of Chemical and Process Engineering, University of Leeds, LS2 9JT Leeds, UK.
² School of Chemical and Process Engineering, University of Leeds, LS2 9JT Leeds, UK; Institute of Process Research and Development, School of Chemistry, University of Leeds, LS2 9JT Leeds, UK.
³ School of Civil Engineering, University of Leeds, LS2 9JT Leeds, UK.
⁴ School of Chemical and Process Engineering, University of Leeds, LS2 9JT Leeds, UK. Electronic address: a.b.ross@leeds.ac.uk.

Abstract

The augmentation of biochar produced at 450 and 600-650 °C and hydrochar produced at 250 °C has been investigated using biochemical methane potential experiments of cellulose. The feedstocks used for the char production included the lignocellulosic (oak wood), macroalgae (Fucus serratus) and aquatic plant (water hyacinth). Biomethane production was improved with the addition of lower-temperature biochars from oak wood (285 mL CH₄/g VS) and water hyacinth (294 mL CH₄/g VS), corresponding to 7 and 11% more than the control. The addition of these two biochars increased the methane production rate of 2.4 and 2.3 times the control, respectively. Higher temperature biochars showed no difference. Conversely, all hydrochars and macroalgae biochars augmentation reduced methane generation by 57-86 %. The chemical and structural composition of each of the chars differed significantly. Surface oxygen functionality appears to be the most important property of the biochars that improved digestion performance.

Keywords: Anaerobic digestion; Biochar; Biomethane; Hydrochar; Surface functionality.

MeSH terms

Anaerobiosis
Charcoal*
Methane*
Wood

Substances

biochar
Charcoal
Methane