Anaerobic Digestion as Key Technology in the Bio-Based Economy

Abstract

In our current society, there is a pressing need to shift from a fossil fuel-based to a bio-based economy in which renewable resources are used for the recovery of energy and production of bio-based chemicals for the industry. For several decades, anaerobic digestion has been the technology par excellence to deal with organic waste streams for waste stabilization and energy recovery in the form of biogas. This contributed a central role to anaerobic digestion in the biorefinery to deal with the massive amounts of waste streams that are generated during the production ofbio-based chemicals. Due to their complex nature, these wastewaters often pose a challenge for anaerobic digestion, thus, integration with other technologies is needed to sustain its central role. The potential ofanaerobic digestion can be extended beyond mere on-site energy recovery. Biogas upgrading to biomethane can be considered an interesting alternative for natural gas, yet, the economic viability will strongly depend on the future market value of electricity. Nutrient recovery and carboxylate production can also be targeted through the anaerobic digestion process, enabling the recovery of higher-value products, compared with biomethane. The potential integration of anaerobic digestion with other technologies for transport fuel production, integrated manure management, and carbon sequestration further emphasizes the versatility of anaerobic digestion and central position in the bio-economy.