Biogas production is an established sustainable process for simultaneous generation of renewable energy and treatment of organic wastes. The increasing interest of utilizing biogas as substitute to natural gas or its exploitation as transport fuel opened new avenues in the development of biogas upgrading techniques. The present work is a critical review that summarizes state-of-the-art technologies for biogas upgrading and enhancement with particular attention to the emerging biological methanation processes. The review includes comprehensive description of the main principles of various biogas upgrading methodologies, scientific and technical outcomes related to their biomethanation efficiency, challenges that have to be addressed for further development and incentives and feasibility of the upgrading concepts.

沼气生产是一个既定的可持续过程，可同时产生可再生能源和处理有机废物。利用沼气代替天然气或将其作为运输燃料进行开发的兴趣日益浓厚，为开发沼气升级技术开辟了新途径。本工作是一项重要的评论，总结了沼气升级和增强的最新技术，尤其是对新兴的生物甲烷化工艺的关注。审查包括对各种沼气升级方法的主要原理的全面描述，与生物甲烷化效率有关的科学和技术成果，进一步发展必须面对的挑战以及升级概念的激励措施和可行性。