Critical issues that can underpin the drive for sustainable anaerobic biorefinery

Depletion of fossil fuel reserves, unstable energy prices, and concerns for climatechange have mobilized the industrial efforts toward energy production from bioresources.Among others, biogas production from organic waste material is an attractive renewable energy source. Biogas can be applied for various purposes, such as electricity production, heating, and transportation, and is an energy carrier that can be efficiently stored for later use. Biogas is expected to play a critical role in reaching the European Union (EU) energy targets due to the wide availability of suitable organic material. In anaerobic digestion (AD), a consortium of microorganisms converts organic material into biogas. Before biogas production becomes economically viable, technologists and microbiologists must increase the yield and production rate of biogas. In this work, we present a review of critical issues on anaerobic digestion for enhanced biogas production by reviewing challenges, trends, and perspectives of the biogas sector