Anaerobic digestion in global bio-energy production: Potential and research challenges

It is clear that renewable resources will play a crucial role in limiting the CO2 emissions. Energy from biomass and waste is regarded as one of the most dominant future renewable energy sources, since it can provide a continuous power generation. In this regard, the application of anaerobic digestion is emerging spectacularly. This manuscript lists and discusses the main beneficial properties of anaerobic digestion. Different types of biomass and waste are suitable for anaerobic digestion: the organic fraction of municipal solid waste, waste oils and animal fat, energy crops and agricultural waste, manure and sewage sludge. The potential, opportunities and challenges of these biomasses are discussed. Typical biogas yield and points of attention are included. The manuscript concludes with an overview and discussion of the major research trends in anaerobic digestion, including the analysis of microbial community development, the extension of anaerobic digestion models, the development of pre-treatment techniques and upgrading of the biogas produced.