Search

Biogas offers significant benefits as a renewable energy source, contributing to decarbonization, waste management, and economic development. This comprehensive review examines the historical, technological, economic, and global aspects of biomethane production, focusing on the key players such as China, the European Union, and North America, and associated opportunities and challenges as well as future prospects from an Australia perspective. The review begins with an introduction to biogas, detailing its composition, feedstock sources, historical development, and anaerobic digestion (AD) process. Subsequently, it delves into major biomethane production technologies, including physicochemical absorption, high‐pressure water scrubbing (HPWS), amine scrubbing (AS), pressure swing adsorption (PSA), membrane permeation/separation (MP), and other technologies including organic solvent scrubbing and cryogenic separation. The study also discusses general guidelines of techno‐economic assessments (TEAs) regarding biomethane production, outlining the methodologies, inventory analysis, environmental life cycle assessment (LCA), and estimated production costs. Challenges and opportunities of biogas utilization in Australia are explored, highlighting and referencing global projections, polarization in production approaches, circularity in waste management, and specific considerations for Australia. The review concludes discussing future perspectives for biomethane, emphasizing the importance of technological advancements, policy support, and investment in realizing its full potential for sustainable energy and waste management solutions. [ABSTRACT FROM AUTHOR]

Recently, salt-assisted pyrolyzation has been deemed an emerging and efficient method for the preparation of biochars due to its facile operation as well as its good structural and chemical properties. In this work, biochars (MBCx) are prepared by heating bamboo powders in eutectic salts (Li2CO3 + K2CO3) at 500–600 °C in the air. Multiple technologies are employed to examine the physiochemical properties of bamboo biochars. Correlations between heating temperature and structural features and carbon dioxide uptakes of bamboo biochars have been investigated. The results show that heating temperature has a significant influence on the physicochemical properties of bamboo biochars. With the elevation of the heating temperature, the defect structures of bamboo biochars gradually ascend, especially when the heating temperature reaches 600 °C. MBCx biochars visibly exceed conventional bamboo biochar prepared via pyrolyzation in a nitrogen stream free of salt addition. Pyrolysis of bamboo in eutectic salts endows biochars with higher oxygen content and more carbon defects, which likely accounts for their better CO2 capture activities. [ABSTRACT FROM AUTHOR]

The Cover Feature shows an Australian map highlighting the distribution of operational biogas facilities. Overlaid is a visual representation of the anaerobic digestion process, illustrating the transformation of waste into biomethane. This artwork symbolizes the regional implementation and technological processes reviewed by F. Wang and co‐workers, which emphasizes Australia′s role in advancing renewable energy solutions...By Ross Swinbourn; Chaoen Li and Feng WangReported by Author; Author; Author [Extracted from the article]

Coal burning emits a significant amount of elemental mercury (Hgo) into the atmosphere, which can cause severe damage to the environment and human health. Here, magnetic FeS2 nanorods are facilely obtained via a low-temperature (200–350 °C) molten salt (KSCN) route. The annealing temperature is found to notably affect the structure and Hgo capture performance of FeS2, while precursors exert subtle effects on the mercury adsorption performance. The Hgo capture ability of FeS2 first increases and then decreases with increasing annealing temperature. The highest magnetism (12 emu/g) and optimal mercury capture performance (Hgo removal efficiency of 96.2%) are achieved over FeS2 nanorods synthesized at 250 °C. This material shows superior performance in the temperature range of 60–180 °C owing to its rod-like structure with ample number of exposed adsorption sites. NO and SO2 are found to only slightly intervene in the mercury removal process. Hgo vapor first adsorbs on the FeS2 surface via physical adsorption followed by conversion into mercury sulfide (HgS) and mercury oxide (HgO) by the oxidation of disulfide ions (S22–) and chemisorbed oxygen (O*) species, respectively. [ABSTRACT FROM AUTHOR]