Role of the microbial community in the anaerobic digester for biomethane production

The rapid increase in population and industrialization has led to an increase in pollution and also the contamination of water resources. Since the removal of waste became a necessity due to an increase in pollution, anaerobic digesters (ADs) were brought into the picture. An AD is a system that is used to convert biodegradable waste into renewable biofuels and by-products. Anaerobic digestion has proven to be one of the most reliable processes with a huge potential in the immediate future. The underlying issues such as sanitation, renewable energy, waste management, health, and biofertilizer production have caused the widespread application of this process in order to eradicate them. In the recent past biomethane has emerged as promising gaseous fuel utilized in cogeneration and trigeneration powerplants. One of the major products of AD is methane, the methanogenic microbial community plays an important role in this anaerobic bioreactor. This process mainly aims at reducing the hazards of wastes on the biosphere. This chapter mainly includes the role of microbes in the AD and their mutualistic behavior resulting in the decomposition of complex organic compounds into simple chemically stable compounds like carbon dioxide and methane. This chapter comprehensively covers the topics to provide complete knowledge, to the readers, of the fundamentals of anaerobic digestion and bioenergy conversations. It includes the basics of different AD designs as well as important major factors involved in methane production and responsible for changes in the population dynamics of methane production. With this chapter, a thorough understanding of the fundamental principles of AD will help readers to perceive new aspects of bioenergy conversions.