ECONOMIC EVALUATION OF A CONCENTRATION SYSTEM FOR VINASSE FROM SUGARCANE ETHANOL PRODUCTION IN BRAZIL

Despite the proven techno-economic feasibility of fertigation, vinasse disposition in sugarcane fields involves high transport costs and has great potential to trigger negative environmental effects. In this context, vinasse concentration systems (VCS) allows significant volume reduction, reducing disposal costs. Since literature lacks data on the implementation and operation of full-scale VCS, the aim of this study is to evaluate techo-economic aspects of different scenarios of fund-raising for this system implementation. Net present value and minimum annual savings (lowest saving required to generate a 12% internal rate of return) were used. Different sources of fund-raising and project lifetimes were assessed. Capital and operational costs were estimated as BRL 46,000,000.00 and BRL 425,000.00, respectively. Capital cost includes equipment, peripherals and installation costs. It also comprises civil infrastructure, electrical installations, automation and instrumentation costs, as well as the interface of this sector with the existing ethanol production plant. Operational cost includes labor, production inputs, electric energy and maintenance. Economic analysis showed negative performance when own capital is invested. However, when capital from the Brazilian Development Bank (BNDES) was used, positive economic performance could be obtained. For example, when 35% of the invested capital is funding by BNDES, the process is feasible.