A study on recycling and reuse of sugar mill industrial waste

Sugar industry is the second largest agro-based industry in Pakistan. Present study determined the economic and environmental benefits of alternative uses of the by-products produced during the manufacturing process. Potential revenue generation of the sugar mill by switching to sustainable sugar industry was also determined. Nitrogen, phosphorus, potassium, organic matter, and organic carbon of pressmud and ash were determined by standard methods. Pressmud contained N (1.68%), P (0.32%), K (3.95%), organic matter (84.00%) and organic carbon (47.13%). Ash had N (0.84%), P (3.95%), K (9.52%), organic matter (31.00%), and organic carbon (17.39%). Thus, indicating their use as land conditioner. The mill generates its own electricity of 33,408 megawatt per hour (MWH) from bagasse; however, it would be more feasible if they used biogas produced rom spent wash which was a by-product of ethanol generation from molasses. In this way, the mill would also be able to sell excess electricity to the government. Current revenue of the sugar mill was 591.552 million PKR from by-products; however, the potential increment of 330.7 million PKR could be easily gained by managing the by-products in sustainable ways.