The Institute of Applied Research, The Galilee Society, P.O.Box 437, Shefa-Amr, Israel E-mail:
Water Sci Technol. 2020 Mar;81(6):1319-1328. doi: 10.2166/wst.2020.234.
Biogas, which typically consists of about 50-70% of methane gas, is produced by anaerobic digestion of organic waste and wastewater. Biogas is considered an important energy resource with much potential; however, its application is low due to its low quality. In this regard, upgrading it to natural gas quality (above 90% methane) will broaden its application. In this research, a novel ex-situ immobilized biomethanation bioreactor (IBBR) was developed for biologically upgrading biogas by reducing CO to CH using hydrogen gas as an electron donor. The developed process is based on immobilized microorganisms within a polymeric matrix enabling the application of high recirculation to increase the hydrogen bioavailability. This generates an increase in the consumption rate of hydrogen and the production rate of methane. This process was successfully demonstrated at laboratory-scale system, where the developed process led to a production of 80-89% methane with consumption of more than 93% of the fed hydrogen. However, a lower methane content was achieved in the bench-scale system, likely as a result of lower hydrogen consumption (63-90%). To conclude, the IBBRs show promising results with a potential for simple and effective biogas upgrading.
沼气主要由 50-70%的甲烷气体组成，是通过有机废物和废水的厌氧消化产生的。沼气被认为是一种具有很大潜力的重要能源资源；然而，由于其质量较低，其应用率较低。在这方面，将其升级为天然气质量（甲烷含量超过 90%）将扩大其应用范围。在这项研究中，开发了一种新型的体外固定化生物甲烷化生物反应器（IBBR），通过使用氢气作为电子供体将 CO 还原为 CH 来生物升级沼气。所开发的工艺基于固定在聚合物基质内的微生物，能够应用高循环来增加氢气的生物利用度。这会增加氢气的消耗速率和甲烷的生成速率。该工艺已在实验室规模系统中成功演示，其中所开发的工艺导致甲烷的生成率达到 80-89%，并且消耗了超过 93%的进料氢气。然而，在中试规模系统中，甲烷的含量较低，可能是由于氢气的消耗较低（63-90%）。总之，IBBR 具有简单有效的沼气升级潜力，结果令人鼓舞。
