Análise energética e econômica do potencial de geração de energia elétrica do biogás proveniente da vinhaça: estudo de caso

Abstract

The sugarcane industry is marked by the large generation of waste that can be used as clean and renewable sources of energy. Stillage, the main waste of alcohol production, contains in its composition highly nutritious characteristics, and at the same time, pollutants. Through the process of anaerobic biodigestion it is possible to reduce these pollutant characteristics and at the same time, to obtain a biogas rich in methane, with high energetic potential. Despite the current crisis in the sugarcane sector, where several plants suffer from huge financial debts, investment in this technology may restructure the sector as a result of economic earning. To support the investment, the initiative must be linked to incentives and public policies, because the sector is extreme important in three segments for Brazil: environmental, social and economic. This work evaluates the implantation of this technology in a sugarcane plant in the region of Dourados, state of Mato Grosso do Sul. Through the energy analysis, it was verified that the plant in question is capable of generating 26% of all electric energy consumed, using the biogas from stillage. The economic analysis validates the feasibility of the project, resulting in a positive return for electric energy commercialization, even with the great instability of the market in the last year, and the high taxes from the sale. A second analysis is performed with the exemption of ICMS, resulting in a return almost five times higher, considering the market average value. Thus, the importance of governmental incentives for the efficient use of energy in the sugarcane industry is reinforced.