Modelling the integration of bagasse pyrolysis into sugar mill energy systems

Pyrolysis degrades biomass under low oxygen conditions to produce an energy-rich gas, bio-oil, and carbon-dense biochar. The resulting bio-oil and gas can be combusted for high energy production, while biochar is a high-value product with potential as a fertiliser and soil amendment product. However, very few studies have been on integrating pyrolysis into the sugar mill energy system. This study aimed to model the integration of bagasse pyrolysis into an energy system based on Victoria Mill. The model was well-validated from previous literature on bagasse pyrolysis and mill system data. The pyrolysis unit’s operating conditions were optimised for steam production, carbon emission reduction, and product value, resulting in 20% less steam production, 16% reduced CO2 emissions, and 76% higher economic profit than current operations. Full steam production could be maintained by bypassing 30% of the bagasse to the pyrolysis unit and 70% directly to the boiler. This configuration led to 12% reduced CO2 emissions and 32% greater economic profits when compared to the current process. Overall, this research showed that the integration of bagasse pyrolysis into sugar mill energy systems has potentially substantial benefits, and its adoption in sugar milling deserves careful analysis.