Department of Biological and Chemical Engineering, Aarhus University, Gustav Wieds Vej 10C, DK-8000, Denmark.
Department of Biological and Chemical Engineering, Aarhus University, Gustav Wieds Vej 10C, DK-8000, Denmark; The Novo Nordisk Foundation CO2 Research Center (CORC), Aarhus University, Gustav Wieds Vej 10C, DK-8000, Denmark.
Bioresour Technol. 2024 May;399:130506. doi: 10.1016/j.biortech.2024.130506. Epub 2024 Feb 27.
Biomethanation of carbon dioxide (CO) from flue gas is a potential enabler of the green transition, particularly when integrated with the power-to-gas chain. However, challenges arise in achieving synthetic natural gas quality when utilizing CO from diluted carbon sources, and the high costs of CO separation using amine-based solutions make large-scale implementation unfeasible. We propose an innovative continuous biomethanation system that integrates carbon capture and CO stripping through microbial utilization, eliminating expenses with the stripper. Stable continuous biomethane production (83-92 % methane purity) was achieved from flue gas-CO using a biocompatible aqueous n-methyldiethanolamine (MDEA) solution (50 mmol/L) under mesophilic and hydrogen-limiting conditions. MDEA was found to be recalcitrant to biodegradation and could be reused after regeneration. Demonstrating the microbial ability to simultaneously strip and convert the captured CO and regenerate MDEA provides a new pathway for valorization of flue gas CO.
从烟道气中生物甲烷化二氧化碳（CO）是绿色转型的一个潜在手段，特别是与电力到气体链集成时。然而，当利用来自稀释碳源的 CO 时，合成天然气的质量会出现问题，而使用基于胺的溶液分离 CO 的高成本使得大规模实施变得不可行。我们提出了一种创新的连续生物甲烷化系统，通过微生物利用来整合碳捕获和 CO 汽提，从而省去汽提器的费用。在中温条件下和氢限制条件下，使用生物相容性的水相 N-甲基二乙醇胺（MDEA）溶液（50mmol/L），从烟道气-CO 中实现了稳定的连续生物甲烷生产（83-92%甲烷纯度）。发现 MDEA 难以生物降解，并且在再生后可以重复使用。证明微生物同时具有汽提和转化捕获的 CO 以及再生 MDEA 的能力，为烟道气 CO 的增值提供了新途径。
