Zhu, Xiaowen;
Blanco, Edgar;
Bhatti, Manni;
Borrion, Aiduan;
(2025)
Improving anaerobic digestion process against acetate accumulation: insights into organic loading rates and nano magnetite additions.
Chemical Engineering Journal
, 512
, Article 162641. 10.1016/j.cej.2025.162641.
Preview |
PDF
Improving anaerobic digestion process against acetate accumulation insights into organic loading rates and nano magnetite additions.pdf - Published Version Download (18MB) | Preview |
Abstract
Anaerobic digestion (AD) offers significant environmental benefits by converting organic waste into biogas and nutrient-rich digestate, supporting circular economy principles. However, acetic acid accumulation during feedstock overload disrupts microbial balance, reducing methane yields and causing instability. This study explored nano magnetite particles (MNPs) as additives to mitigate acetate stress and enhance AD performance. MNPs were applied using pretreatment and post-treatment strategies. Pretreatment with 20 nm and 50 nm MNPs improved methane production by 24.4 % and 19.1 %, respectively, compared to acetate-stressed systems. Post-treatment with 20 nm MNPs resulted in a 15.7 % methane production boost and a 16.4 % volatile solids reduction, facilitating rapid system recovery. MNPs acted as electron conduits, supporting direct interspecies electron transfer and providing bioavailable iron, crucial for methanogenic enzymatic functions. These mechanisms enhanced microbial resilience, mitigated oxidative stress, and restored functional pathways disrupted by acetate accumulation. The size-dependent effects of MNPs indicated that smaller particles (20 nm) were more effective in promoting acetate methanation, while larger particles (50 nm) enhanced microbial viability, highlighting the potential for customised, combined applications under diverse scenarios in AD systems. Economically and environmentally, MNPs enhanced methane production and reduced slurry output by up to 9.4 %, decreasing disposal costs and carbon emissions, thereby improving system sustainability. Future research should optimise MNP dosing strategies and explore recovery and recycling methods to ensure economic feasibility. At the tested concentrations (100 mg/L), MNPs offer a scalable, environmentally compatible solution to enhance AD performance, making them a promising additive for industrial-scale organic waste management.
| Type: | Article |
|---|---|
| Title: | Improving anaerobic digestion process against acetate accumulation: insights into organic loading rates and nano magnetite additions |
| Open access status: | An open access version is available from UCL Discovery |
| DOI: | 10.1016/j.cej.2025.162641 |
| Publisher version: | https://doi.org/10.1016/j.cej.2025.162641 |
| Language: | English |
| Additional information: | © 2025 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). |
| Keywords: | VFA accumulation, Feedstock overload, MNP, Anaerobic Digestion, Metabolism, Statistical analysis |
| UCL classification: | UCL UCL > Provost and Vice Provost Offices > School of Life and Medical Sciences UCL > Provost and Vice Provost Offices > UCL BEAMS UCL > Provost and Vice Provost Offices > School of Life and Medical Sciences > Faculty of Life Sciences UCL > Provost and Vice Provost Offices > School of Life and Medical Sciences > Faculty of Life Sciences > Div of Biosciences UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Engineering Science > Dept of Civil, Environ and Geomatic Eng |
| URI: | https://discovery.ucl.ac.uk/id/eprint/10211691 |
Archive Staff Only
 |
View Item |
