Advanced Utilization and Management of Biogas

Biogas is extensively produced on a local basis and therefore represents a valuable renewable energy resource. It is widely available almost everywhere as a product of biological wastewater treatment plants, sewage facilities, and refuse landfill sites. However its current utilization for heat production is inefficient and polluting, and, in the case of poor quality biogas, exacerbated by detrimental venting to the atmosphere. Accordingly, innovative and efficient methods for utilization of biogas for the production of energy or high added-value chemicals are highly desirable. Such advances could lead to a substantial re-engineering and optimization of wastewater treatment plants, reducing both operating costs and environmental damage due to gas emissions, at the same time creating efficient systems for energy generation and synthesis of chemicals. The composition of biogas (50–70% CH4, 25–50% CO2, 1–5% H2 with minor impurities—NH3, H2S and halides) makes it advantageous for direct dry reforming for synthesis gas and/or H2 production, as well as an effective feedstock for fuel cell applications. Biogas upgrading to substituted natural gas (SNG) could offer the possibility to produce a high value fuel for transport applications or grid injection. Furthermore, the removed CO2 from the upgrading process could be used in renewable driven fuel synthesis processes (e.g., power-to-gas process, algae growing, etc…) as a sustainable carbon stock thus enhancing possibilities for advanced polygeneration systems. Ultimately, biogas offers considerable benefits for clean, efficient electrical power generation with minimal environmental impact, especially in comparison to coal-based power generation. Together with natural gas, biogas can be considered as a “bridge fuel” for the 21th century, enabling transition to a low-carbon energy economy. In this regard, direct biogas fuel cells (DBFCs) have attracted much research interest. New and effective carbon and H2S tolerant anodic materials for DBFCs have been developed, thanks to our deeper understanding of promotion phenomena occurring in heterogeneous catalysis and electrocatalysis, and the development of nano-structured materials. The present Research Topic covers promising recent research and trends in biogas utilization and management, especially H2S and other trace compounds removal from biogas streams, biogas reforming to syngas and/or hydrogen, application of novel stable catalysts, the construction, operation and performance DBFCs, and the development and characterization of nano-structured DBFC anodes. Also of interest are modeling and parametric simulations of DBFCs, energy and exergy calculations along with analysis of biogas or methane-fuelled fuel cell aided plants. Further innovative concepts for biogas utilization and/or management and plant design are also highly desirable.