A systematic review of prevalent soy waste management techniques

Soybeans are one of the major oilseed crops that generate huge agro-waste. On improper management, soybean waste can turn bad and become an environmental problem. This review focuses on the untapped potential of soybean waste towards energy generation and sustainable agricultural practice. If soybean straw were open-burned, one-quarter of its mass would become carbon dioxide and one-eighth of sulfur dioxide, contributing to increased greenhouse gas levels, air pollution, and soil acidification. An analysis of 20 studies from 2010 to 2022 revealed that 65 % of research on soybean waste is concentrated in India and China, while the other leading soybean-producing regions do not receive much attention. Additionally, there is a substantial lack of biogas and bioenergy technologies since only 7 % of the studies were about anaerobic digestion and co-composting. There are promising pathways for the valorization of waste soybeans that include the hydrogen yield via sub-critical water hydrolysis with a maximum improvement of 60 % and pyrolysis techniques for producing biochar. The review stands out significantly, thus indicating a critical need for an integrated system of waste management supported by government policies-increased crop pricing, infrastructure, and local waste management initiatives. Finally, the above-mentioned differences can transform soybean waste from a liability to an asset by contributing toward energy sustainability, carbon neutrality by 2070, and global SDGs. This research sets a blueprint for future directions for research and policy considerations aimed at transforming the management of agro-waste and creating an innovative and sustainable development compass.