Deepali Nimbalkar and Kapil Uphade
Vasantdada Sugar Institute, Pune, India; ds.nimbalkar@vsisugar.org.in
Water is a finite and valuable resource with great significance for the sustainability of the sugar industry. Increasing water scarcity, stringent environmental regulations, and stakeholder awareness have put pressure on the industry to reduce its water usage and avoid contamination of existing water resources through the release of effluents. This paper reviews the recent developments in wastewater treatment and reuse in the sugar sector globally. Sugarcane contains around 70% water that can theoretically contribute to the process water leading to zero water requirement if effectively managed. However, that is rarely the case due to several challenges in implementation. Good examples with maximum recycling and reuse are discussed in this paper. Wastewater treatment and disposal methods in sugar mills vary in different regions depending upon environmental regulations. There is a lack of regulation in some countries with effluents being discharged untreated, whereas other countries use the treated/untreated effluents for irrigation. All these have environmental consequences. Wastewater treatment and reuse in sugarcane processing have acquired great importance as a part of achieving zero liquid discharge. Segregation of waste streams plays an important role in recycling and reuse. Regulatory compliance, water scarcity, economic benefits and sustainability goals are the drivers for wastewater treatment and reuse while treatment costs, technical expertise, quality control and monitoring continue to remain challenges in smaller mills. These can be addressed through integration of innovative technologies, robust regulatory frameworks and capacity building initiatives. This is essential to ensure environmental sustainability of the sugar industry.