Evaluation of anaerobic digestibility of energy crops and agricultural by-products

Abundant wastes from the food and drink supply chain are valuable and infrequently used as anaerobic digestion (AD) substrates. This study quantifies their biomethane potential to contribute to solid waste reduction and energy production. 29 organic materials were evaluated: energy crops (6), pre-treated agricultural by-products (5), livestock slurries (3), agro-industrial wastes (7), fruit and vegetable wastes (4) and co-digestion mixtures of chicken litter (CL) and fruit wastes (4). Results showed highest biogas yields for rendered fat washings (1379 ± 125 mL/g VSfeedstock), fish waste (898 ± 107 mL/g VSfeedstock) and potato waste (768 ± 27 mL/g VSfeedstock). Synergistic benefits of co-digestion were evidenced. CL (20%) with avocado pulp (80%) led to 84% higher biogas than expected from contribution of single substrates.