Sustainable energy conversion through integrated anaerobic digestion-pyrolysis with carbon capture, storage, and management: modeling, analysis and techno-economic feasibility

Singh, Rickwinder; Lindenberger, Christoph; Chawade, Aakash; Vivekanand, Vivekanand

doi:10.1016/j.enconman.2025.120960

Abstract

This study proposes a novel carbon-negative biomethane-producing process from organic waste and lignocellulosic biomass using an integrated system of anaerobic-digestion and co-pyrolysis to promote bioenergy with carbon capture and storage. This process model comprises various processes, primarily anaerobic-digestion, dewatering, pyrolysis, catalytic steam reforming, methanation, and carbon-dioxide capture by pressure swing absorption. Integrated system achieved process efficiencies of 47.4%, 57.6%, and 61.6% at pyrolysis temperatures of 450 degrees C, 550 degrees C, and 650 degrees C, respectively, along with efficient catalytic steam reforming. Mass and energy balances revealed that co-pyrolysis temperature and steam reforming significantly affect biomethane yield and energy use. Sensitivity analysis showed that dewatering of slurry with screw press and microwave co-pyrolysis of digestate with lignocellulosic biomass at 650 degrees C provided significant results in terms of maximisation of biomethane with an acceptable range of carbon dioxide capture. Integrated anaerobic digestion and co-pyrolysis system achieved 100% waste utilisation, producing biomethane with carbon capture in the form of carbon-dioxide storage and biochar. A techno-economic analysis reveals an return on investment of 17.1%, with a 4.5-year payback period, confirming strong financial viability. Finally, the economic viability of the system would be increased if stored carbon is sold as a commodity and carbon credit taxes are considered.

Keywords

Organic waste; Anaerobic digestion; Pyrolysis; Bioenergy; Carbon capture; Sensitivity analysis; Technoeconomic analysis

Published in

Energy Conversion and Management
2026, volume: 350, article number: 120960
Publisher: PERGAMON-ELSEVIER SCIENCE LTD

SLU Authors

Chawade, Aakash
- Department of Plant Breeding, Swedish University of Agricultural Sciences

UKÄ Subject classification

Bioenergy

Publication identifier

DOI: https://doi.org/10.1016/j.enconman.2025.120960

Permanent link to this page (URI)

https://res.slu.se/id/publ/145733