Anaerobic Digestion in Europe: Key to Waste Management, Challenges, and Perspectives

Anaerobic digestion is a natural occurring process developed by a wide microbial consortium. From it, CH4, a valuable biofuel, is produced from agro-industrial wastes. The European Union has an enormous potential to continue the development of this technology. Not only the countries within it are leading the discoveries and implementing novel strategies for the process, but also they have a large amount of usable resources as raw material. Furthermore, current policies for the adaptation of the circular economy and green technologies enhance the opening of biogas plants. It is possible to search for the improvement of the process by different means. For example, reactor design has a main task, which is to provide the adequate conditions to enhance microbial metabolism. On the other hand, there are technologies to improve biogas to biomethane, which can be injected to the grid in the form of gas or electricity. However, if the process is not sustainable from an energetic or economic view, the process has no sense. To know this, technoeconomical analyses are performed. This chapter describes the current political conditions that enhance the circular economy within the EU. In addition, examples of potential modifications in reactors’ design, response from co-digestion experiments, and potential substrates for the process are provided. At last, technoeconomical examples are explained too.