Integration Approach of Anaerobic Digestion and Fermentation Process Towards Producing Biogas and Bioethanol with Zero Waste: Technical

Abstract

The rapid increase in the world population has caused an enormous increase in the demand of energy. Growing demand has resulted in a shortfall in conventional energy resources. Due to that and because of the major negative impacts of fossil fuel on the environment and other aspects as well, the necessity toward finding alternative cheap, renewable, and environmentally friendly energy resources has significantly arose. Biomass as an energy resource has a potential to be a good alternative for non-renewable energy resources. Anaerobic digestion process is one of the most commonly biological conversion process used in converting biomass into biofuels. It has been extensively applied in many studies for converting several types of feedstocks and has proved its significant effectiveness. (AD) digestates are generally composed of solid and liquid streams. Those streams are rich in nutrients and contain undigested materials which have not been digested in the digestion process. Despite the significant effectiveness, it would contribute in major issues if it has been applied at large scale, as the amount of digestates which would be generated is quite high. Due to that and to take an advantage of the digestates in the production of biofuel and bioproducts as well, the interests in enhancing and utilizing anaerobic digestion residues have recently much increased. Bioethanol is one of the most promising liquid biofuel. It is eco-friendly alternative to fossil fuels. In recent years, number of studies have investigated the integration approach of producing biogas and bioproduct in which would result in zero waste. However, this paper discusses mainly an integration approach for producing two promising renewable energies can be utilized in many applications with no waste generated. This approach is still at an early stage and requires further studies to improve the properties of the biofuels and high-value bio-based products produced.