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Sugarcane Bagasse (SCB) has some characteristics that hinder its direct use as fuel. Torrefaction pre-treatment could be considered to improve the SCB properties for an energy use and to reduce the impact of storage on the reduction of these energy properties. SCB were torrefied at 290 °C in a screw reactor, during 5, 7.5 and 10 min. Then, raw and torrefied SCB samples were exposed successively to water-leaching and to white and brown rot fungi, to emulate storage conditions. Mass loss after water-leaching process, moisture content and weight loss due to fungal deterioration after 2, 4, 8, 12, 16 weeks were recorded on each SCB samples. Finally, chemical composition and High Heating Value of the torrefied samples were measured to determine the alterations compared to raw SCB during their storage mimic. Increasing torrefaction duration improves the SCB decay resistance. According to the fungal exposure duration, loss of carbon was recorded, however, HHV remain higher for torrefied SCB than those of raw SCB. Carbon contents and HHV values of raw and torrefied SCB during Trametes versicolor exposure [55.20% > C > 44.55% and 21.260 MJ kg−1 > HHV >17.307 MJ kg−1, results from all tests combined.], and during exposure to Coniophora puteana [55.20% > C > 46.25% and 21.260 MJ kg−1 > HHV > 17.699 MJ kg−1] tend to decrease. Severe torrefaction is therefore a good way to improve SCB energy properties while limiting loss of their energy properties during storage.

Torrefaction is a promising technology to produce woody sustainable materials and biochar for combustion and gasification. To aid in the process and reactor design concept, numerical models are applied to predict processes parameters giving treatment time estimation, solid and volatile yields, and calorific values of the solid fuels. In this work, a hardwood (Eucalyptus grandis) was investigated by using thermogravimetric analysis (TGA), as well as elemental analysis, which can reveal the thermal events and identify degradation products as a function of treatment time and temperature. A numerical prediction based on a two-step kinetics model was employed to predict solid yield, elemental composition, higher heating values (HHV), and its enhancement factor during the treatment. The further analyzed prediction 3D surfaces and profiles allows clear identification of the torrefaction severity. The predicted HHV’s showed enhancement factors up to 10.2% for severe torrefaction. The obtained kinetic rates for Eucalyptus grandis, as well as the numerical results, can provide useful information for industrial operation and reactor projects., Proceedings of the 28th European Biomass Conference and Exhibition, 6-9 July 2020, Virtual, pp. 694-698

Torrefaction is a thermal modification used to the enhancement of fuel characteristics. This paper describes the effect of an innovative thermo-acoustic torrefaction reactor on the physical and chemical properties of torrefied Eucalyptus grandis wood. The aim was to evaluate the combined effect of the temperature (250 and 270 °C) and acoustic frequencies (1411,1810,2478 and 2696 Hz) by the assessment of the solid yield and its deviation, proximate and elemental analysis as well as energy content. A numerical model of kinetics reaction rates and solid composition allowed the evaluation of the thermo-acoustic torrefaction experiment showing faster reaction rates for treatments under acoustic. Statistical analysis results indicated that the applied frequencies affect the higher heating value but did not significantly affect the other parameters. However, its dynamic profiles show that acoustic may accelerate the degradation process. The kinetic numerical simulation of the acoustic coupling resulted in faster conversion rates for the solid pseudo-components leading to a stronger degradation of the intermediate product., Proceedings of the 28th European Biomass Conference and Exhibition, 6-9 July 2020, Virtual, pp. 567-573

O objetivo deste trabalho é apresentar os resultados da experiência de ministrar a distância uma disciplina em Gerenciamento de Projetos, para cursos presenciais de graduação da Universidade de Brasília. O conteúdo de gestão de projetos é apresentado em forma de exposição dialogada, durante as aulas são discutidos estudos de caso relacionados a diversos temas e realizadas atividades individuais e, como trabalho final, a elaboração de um Plano de Gerenciamento do Projeto em energias alternativas. A disciplina foi ministrada na modalidade a distância, utilizando a ferramenta GoToMeetingque é um software de videoconferência eOpenProj que é um software de gestão de projetos.Todo o material usado nas aulas era disponibilizado via plataforma Aprender, que é um Ambiente Virtual de Aprendizagem concebido para apoiar os professores e alunos nas atividades de ensino e aprendizagem as disciplinas da UnB. No último mês de aula, para melhor rendimento, foram realizados atendimentos por grupos, tanto nos horários de aula quanto em outros dias e horários. No final do curso os alunos responderam um questionário contendo 15 questões, com objetivo de avaliar a disciplina eletiva em Gerenciamento de Projetos, ministrada a distância. A partir dos resultados, foram levantados pontos de melhorias, como por exemplo, avaliar mais rapidamente as atividades realizadas e dar devolutiva aos alunos, fazendo com que o conteúdo possa ser entendido com clareza e melhor consolidado, melhoria implementada na turma do primeiro semestre de 2018. A disponibilidade do professor, tanto durante as aulas como extra-aula é um ponto a ser mantido e sempre aperfeiçoado, pois foi reconhecido positivamente pelos alunos.