Biogas production generates anaerobic digestate, a nutrient-rich byproduct that, if unmanaged, can pose environmental and safety risks such as greenhouse gas emissions and soil contamination. This review proposes globally applicable guidelines for sustainable digestate management, emphasizing nutrient conservation, micropollutant control, and alignment with carbon neutrality and the Sustainable Development Goals. It evaluates biological, chemical, thermal, and mechanical valorization methods to improve digestate quality before soil application, enhancing fertilization benefits while reducing environmental impacts. The review provides practical insights and research directions to support circular and sustainable management of anaerobic digestate.
