Biogas Production from Organic Waste: Recent Progress and Perspectives

Anaerobic digestion (AD) from organic waste has gained worldwide attention in reducing greenhouse gas emissions, lowering fossil fuel combustion, and facilitating a sustainable renewable energy supply. Biogas mainly consists of methane (CH₄) (50–75%), carbon dioxide (CO₂) (25–50%), hydrogen sulphides (H₂S), hydrogen (H₂), ammonia (NH₃) (1–2%) and traces of other gases such as oxygen (O₂) and nitrogen (N₂). Methane can replace fossil fuels in various applications such as heat and power generation and the transportation sector. The degradation of organic waste through an AD process offers many advantages, such as the decrease of pathogens and prevention of odour release. The digestate from anaerobic fermentation is a valuable fertilizer, however, the amount of organic materials currently available for biogas production is still limited. New substrates, as well as more effective conversion technologies, are needed to grow this industry globally. This paper reviewed the latest trends and progress in biogas production technologies including potential feedstock. Recycling of waste has recently become an important topic and has been explored in this paper.