Energy produced from renewable sources such as sun or wind are intermittent, depending on circumstantial factors. This fact explains why energy supply and demand do not match. In this context, the interest in biomethanation has increased as an interesting contribution to the Power-to-gas concept (P2G), transforming the extra amount of produced electricity into methane (CH4). The reaction between green hydrogen (H2) (produced by electrolysis) and CO2 (pollutant present in biogas) can be catalysed by different microorganisms to produce biomethane, that can be injected into existing natural gas grid if reaching the standards. Thus, energy storage for both hydrogen and electricity, as well as transportation problems would be solved. However, H2 diffusion to the liquid phase for its further biological conversion is the main bottleneck due to the low solubility of H2. This review includes the state-of-the-art in biological hydrogenotrophic methanation (BHM) and membrane-based technologies. Specifically, the use of hollow-fiber membrane bioreactors as a technology to overcome H2 diffusion limitations is reviewed. Furthermore, the influence of operating conditions, microbiology, H2 diffusion and H2 injection methods are critically discussed before setting the main recommendations about BHM.

中文翻译：

---

生物甲烷化和使用膜技术克服 H2 传质限制的概述


太阳能或风能等可再生能源产生的能源是间歇性的，具体取决于环境因素。这一事实解释了为什么能源供需不匹配。在这种情况下，人们对生物甲烷化的兴趣增加了，这是对电转气概念 （P2G） 的一个有趣贡献，将产生的额外电力转化为甲烷 （CH4）。绿色氢气 （H2）（通过电解产生）和 CO2（沼气中存在的污染物）之间的反应可以由不同的微生物催化产生生物甲烷，如果达到标准，可以将其注入现有的天然气管网。因此，氢能和电能的储能以及运输问题都将得到解决。然而，由于 H2 的溶解度低，H2 扩散到液相中以进一步进行生物转化是主要瓶颈。本综述包括生物氢营养甲烷化 （BHM） 和基于膜的技术的最新进展。具体来说，综述了使用中空纤维膜生物反应器作为克服 H2 扩散限制的技术。此外，在设定有关 BHM 的主要建议之前，将严格讨论操作条件、微生物学、H2 扩散和 H2 注射方法的影响。