Integrated sugarcane farming and sugar milling with selective fermentation: A simulation-based approach

Selective fermentation of reducing sugars in cane juice harnesses the advantageous productivity of high-yielding sugarcane cultivars for increasing products from limited arable land. Without this technology, the altered compositions of cane juice often lead to additional environmental impacts due to increased consumption of externally supplied energy and compensated yield of sugar. In this paper, the effects of coordinated transition of sugarcane farming and sugar milling on the yield of final products, energy consumption, operability in the crystallization process, and economic feasibility were analyzed in simulation across various sugarcane cultivars. An integrated sugarcane farming and sugar milling process model (SugaNol) was extended from a previous work to consistently balance mass and energy considering the characteristics of the selective fermentation technology. A case study demonstrated that the coordinated introduction of selective fermentation with the high-yielding cultivar enhanced sugar production by 8.5% and ethanol production by 17.9%, improved operability in the crystallization process, and lead to a cleaner production by achieving above without consuming additional fossil fuels, although the market price of ethanol should be under 95 JPY L⁻¹ for profitability. Furthermore, the specific characteristics of cultivars to make selective fermentation economically feasible are presented as a guideline for future cultivar development.