Monday, April 30, 2007

Biodiesel and biogas production: New trend of alternative Brazilian energy sources

Luiz Carlos Martins das Neves1, Marcio Junji Kobayashi1, Thaís Miranda Rodrigues1, Attilio Converti2, and Thereza Christina Vessoni Penna1. (1) Department of Biochemical and Pharmaceutical Technology, School of Pharmaceutical Sciences, University of São Paulo, Av. Prof. Lineu Prestes, 580, Bl. 16, São Paulo, 05508-900, Brazil, (2) Dipartimento di Ingegneria Chimica e di Processo, Università degli Studi di Genova, Opera Pia 15, I-16145, Genova, Italy

Energy has been the base of human society since the more remote civilizations. Actually, energetic sources are each more necessary to promote the economic, social and cultural development. Alternative energy sources (wind, solar, biofuels) show capability to minimize the exhaustion and environmental problems of traditional energy sources. Biodiesel and biogas has been presented as innovators and no-aggressive alternative fuels. Biodiesel is a fuel produced by the reaction between renewable sources (vegetable oils or animal fats) with methanol or ethanol and can be used in mixture with traditional diesel or as a pure fuel. Because 20% of Brazilian diesel consumption (36 billion of liters) has been imported, governmental programs are directed to small farmers to improve the vegetable oils production to substitute 5% of diesel consumed. In the other hand, industrialized and urbanized regions show a great environmental problem with the generation of pollutant residues, which can be utilized as a biogas source, basically formed by methane, and obtained by organic residues degradation from microorganisms as Bacillus subtilis. Great cities in development countries show the potential energy generation of 20 MW from the utilization of 50 m3/s of urban residue. This work aims to evaluate the potential of production and application of biodiesel and biogas as alternative energy sources produced, respectively, in rural and urbanized areas and to compare the viability with other knowledge energy sources (oil, hydroelectricity, thermoelectricity, nuclear, wind and solar energies).