Work

Scaling up biological methanation in trickle bed reactor: performance and techno-economic feasibility analysis

Year: 2026

Type: article

Abstract: • >95% CH 4 efficiency achieved in 100 L TBR, after 364 days of continuous operation. • Metabolic water management was crucial for stability at GRT < 2 h. • 14.5 m 3 /m 2 ·d hydraulic rate optimized conversion, solving 1 h GRT instability. • Trace metals (Fe/Ni/Co) showed dilution effects, needing periodic replenishment. • Competitive bio-LNG costs (∼2.5 €/kg) are achievable with low-cost renewable power. Biological methanation in trickle bed reactors (TBRs) offers a sustainable pathway for converting carbon dioxide (CO 2 ) and hydrogen (H 2 ) into low-carbon methane (CH 4 ). This study bridges the gap between lab- and industrial-scale deployments by scaling a microbial consortium-optimized TBR system 100-fold (from 1 L to 100 L) . Operating under thermophilic conditions (55 ο C) for 364 days of continuous pilot-scale operation, the pilot system achieved a CH 4 purity of greater than 95% at gas retention times (GRTs) as low as 1 h, with peak methane concentration (99.7% CH 4 ) at a 3-hour GRT. Key challenges included metabolic water dilution and low H 2 conversion , mitigated by adjusting hydraulic loading rates and nutrient replenishment. Trace metal analysis confirmed the sufficiency of Fe/Ni/Co, although dilution effects emerged at high water production rates. Techno-economic evaluation of the assessed PtM system revealed a baseline production cost of 2.47 €/kg LNG, with performance strongly governed by electricity price and electrolyser efficiency. Under low-cost renewable electricity, bio-LNG cost could fall to ∼ 1.7 €/kg, underscoring the competitiveness of biological methanation.

Source: Bioresource Technology

DOI: 10.1016/j.biortech.2026.134414

Authors: Alexandros Chatzis, Aikaterini Xirostylidou, Konstantinos N. Kontogiannopoulos, Petros Samaras, Anastasios I. Zouboulis, Panagiotis G. Kougias

Institutions: Aristotle University of Thessaloniki, Hellenic Agricultural Organization - DIMITRA, International Hellenic University

Language: English

Topic: Anaerobic Digestion and Biogas Production

Subfield: Building and Construction

Field: Engineering

Domain: Physical Sciences

SDGs: Affordable and clean energy, Climate action, Responsible consumption and production, Clean water and sanitation, Industry, innovation and infrastructure

Open Access status: hybrid

Estimated APC paid: $4,880