The process of biological methanation (BM), which involves the reaction between carbon dioxide (CO) and hydrogen (H) producing methane (CH), is a circular economy strategy that can alleviate the problem of energy storage and also reduce CO emissions. By harnessing a renewable energy source to facilitate H production through water electrolysis and by capturing CO, e.g. from industrial flue gases or biogas, this Power-to-Gas (PtG) technology produces CH, the predominant compound of synthetic natural gas (following appropriate purification/enhancement towards biomethane). During the last decade, BM process has been examined fundamentally by various research groups both in lab-scale, as well as in pilot-scale experiments/applications. Nevertheless, a significant portion of these studies lack presentation of technical details and implementation strategies, regarding the operation of existing BM units in real-world applications. The current work aims to offer a thorough review of biological methanation, focusing on its practical implementation, particularly examining the most notable full-scale (industrial) applications utilizing this technology. To the best of the authors’ knowledge, the specific review provides the first comprehensive insight on the application of biological methanation and potentially consists a ‘technology catalogue’ that includes both the latest lab-/pilot-scale research advancements and the most significant demonstration-/full-scale plants currently installed in Europe. After the presentation of BM process fundamentals and the respective basic reactor types, the study presents the current research, and also substantial information, regarding the operation of certain (largest) full-scale BM plants, installed in Germany, Switzerland and Denmark. Biomethanation integrates solutions to pressing environmental challenges, likely related to waste and carbon emissions reduction and aligns with the principles of the circular economy, that aims to minimize waste and make the most of resources by reusing and recycling. Additionally fits into the emerging field of Carbon Capture and Utilization (CCU) aimed at mitigating Greenhouse Gas (GHG) emissions. However, although the scale-up of BM process has evolved, further operating information and economic data on demo- and full-scale plants should be appropriately investigated to ensure the economic feasibility and, therefore, the widespread application of this PtG technology.

中文翻译：

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生物甲烷化 (BM)：对近期研究进展和全规模 BM 装置实际实施的最先进回顾


生物甲烷化（BM）过程涉及二氧化碳（CO）和氢气（H）之间的反应产生甲烷（CH），是一种循环经济策略，可以缓解能源储存问题并减少二氧化碳排放。利用可再生能源通过水电解和捕获二氧化碳来促进氢气生产，例如这种电转气 (PtG) 技术从工业烟气或沼气中产生 CH，这是合成天然气的主要化合物（经过适当的纯化/增强生物甲烷后）。在过去的十年中，不同的研究小组在实验室规模以及中试规模的实验/应用中对 BM 工艺进行了根本性的检验。然而，这些研究的很大一部分缺乏关于现有 BM 单元在实际应用中的操作的技术细节和实施策略的介绍。目前的工作旨在对生物甲烷化进行彻底的审查，重点关注其实际实施，特别是研究利用该技术的最著名的全面（工业）应用。据作者所知，具体综述提供了对生物甲烷化应用的第一个全面的见解，并可能包含一个“技术目录”，其中包括最新的实验室/中试规模的研究进展和最重要的示范- /目前在欧洲安装的全规模工厂。在介绍了 BM 工艺原理和各自的基本反应器类型之后，该研究介绍了有关德国、瑞士和丹麦安装的某些（最大）全规模 BM 工厂运行的当前研究以及大量信息。 生物甲烷化整合了解决紧迫环境挑战的解决方案，可能与减少废物和碳排放有关，并符合循环经济的原则，旨在通过再利用和回收来最大限度地减少废物并充分利用资源。此外，还适合旨在减少温室气体 (GHG) 排放的碳捕获和利用 (CCU) 新兴领域。然而，尽管 BM 工艺的规模化已经发展，但仍应适当研究示范工厂和全规模工厂的进一步运行信息和经济数据，以确保经济可行性，从而确保该 PtG 技术的广泛应用。