Challenges and strategies for waste food anaerobic digestion: insights and future directions

Anaerobic digestion has emerged as a promising technology for the treatment of food waste as a result of its ability to produce renewable energy and mitigate environmental concerns. This article explores the challenges associated with waste food and proposes feasible solutions with future directions to improve its efficiency and sustainability. The main challenge in the AD process is the variable composition of waste food, including moisture content, nutritional content, and the presence of inhibitory substances (lipids and high ammonia) that lead to process instability. Fast-less feasible solutions include pretreatment techniques to improve substrate degradability, co-digestion with complementary substrates, and optimization of process parameters. Future directions for the anaerobic digestion of waste food involve the integration of emerging technologies, i.e. in situ product recovery, bioelectronic systems, and hybrid systems to maximize resource recovery and energy generation. In addition, efficient monitoring development, control systems, modeling tools, and comprehensive technoeconomic assessments will aid in the optimization and scale-up of anaerobic digestion facilities. Furthermore, optimizing process parameters, such as temperature, pH, and hydraulic retention time, has proven effective in enhancing AD performance. Overall, this review article provides information on challenges faced by waste food anaerobic digestion presents feasible solutions, and highlights future directions to explore process parameters, pretreatment methods, innovative monitoring and control solutions, process modeling tools, and techno-economic assessments that will facilitate the efficient operation and scalability of waste food anaerobic digestion systems.