What should we do with CO₂ from biogas upgrading?

Climate Performance of Liquefied Biomethane with Carbon Dioxide Utilization or Storage

“…This study includes six alternatives for CO₂ utilization, a CCS pathway and a base case where CO₂ from biogas upgrading is captured and released into the atmosphere (CCR). The CCU options were selected based on technology readiness level and their potential to reduce various fossil-based processes and CO₂ emissions, in accordance with the methodology of Cordova et al [35]. Thus, these options are available for implementation and present potential to be integrated in biogas upgrading systems at mid and short term, and can contribute to reducing the lock-in to fossil-based system.…”

“…Several overviews of CCU and CCS options have been presented in recent years, including the study by Anwar et al [34] and the report by the International Energy Agency [14]. Cordova et al [35] presented a methodology for comparing different aspects of CCU and CCS options for biomethane production. Many previous studies on specific utilization of CO₂ from biogas focus on methanation, where H₂ is added either to the digester (in-situ) or to the separated CO₂ flow (ex-situ) to increase the methane output.…”

Biogas Upgrading by Intensified Methanation (Sesar): Reaction Plus Water Adsorption - Desorption Cycles with Ni-Fe/Al2o3 Catalyst and Lta 5a Zeolite

“…The CO 2 , on the other side, could be sequestrated from highly concentrated streams such as biogas (ca. 40% v CO 2 + 60% v CH 4 ) or other sources like biomass or sewage sludge gasification streams [9,10]. Sabatier reaction (r.1) produces methane and water [11] with the aid of a catalyst.…”