Sustainable valorization of sugar industry waste: Status, opportunities, and challenges

Sugarcane processing in sugar industry results in generation of vast amounts of wastes, which can be valorized to biofuels and value-added chemicals based on the concept of circular bioeconomy. For successful commercialization, economic and technological bottlenecks must be clearly identified. In this review, the state of the art of various valorization routes are discussed for each waste stream. Subsequently, studies quantifying the environmental impacts and performing techno-economic assessment are reviewed. The scope and bottlenecks involved in the commercialization of these routes are identified and discussed. The review shows that electricity production from bagasse has matured as a technology but the production of value-added chemicals is still lagging. Here, downstream separation and purification are the major hurdles needing technological innovation. Moreover, indirect environmental and human health benefits due to waste valorization are not adequately accounted for. Further, strong trade-offs between economic and environmental performance exist, necessitating systematic and region-specific decision-making framework.