Modelação dos parâmetros de combustão de biomassa florestal para a produção de energia
Ficheiros
Data
2016-09-26
Título da revista
ISSN da revista
Título do Volume
Editora
Resumo
O presente trabalho surge no sentido de compreender a relevância e influência de diversos parâmetros associados à combustão de biomassa florestal. Os parâmetros analisados neste estudo foram a composição da biomassa florestal, o seu teor de humidade, o excesso de ar da combustão, a dissociação da água, o diâmetro da partícula de biomassa a queimar e o poder calorífico. Para fins comparativos com o gás natural foram também analisadas as emissões de CO2 inerentes à combustão.
Os tipos de biomassa utilizados foram a biomassa de Pinus pinaster e a biomassa de Eucalyptus globulus, biomassas escolhidas devido à sua enorme abundância em Portugal.
A compreensão dos parâmetros enunciados previamente foi realizada recorrendo a uma metodologia de cálculo apoiada pela bibliografia existente. Com estes parâmetros foi encontrada, para a biomassa de Pinus pinaster e para a biomassa de Eucalyptus globulus, a temperatura adiabática de chama, tendo em consideração a variação do teor de humidade entre 0% e 60%, a variação do excesso de ar entre 0% e 100% e também considerando a combustão com e sem dissociação da água. Foram também observados os tempos de queima, associados à combustão da biomassa de Pinus pinaster e da biomassa de Eucalyptus globulus, para os quais, além do teor de humidade, do excesso de ar e da dissociação da água, o diâmetro da partícula de biomassa varia entre 1,0mm e 10,0mm.
Foram comparados os resultados da combustão de ambos os tipos de biomassa por forma a concluir qual destes dois tipos de biomassa é o mais favorável para a produção de energia. Destes resultados constam também estudos sobre a viabilidade económica (€/kWh) e sobre as emissões de CO2, quando comparada a combustão dos dois tipos de biomassa usados com a combustão de gás natural.
The present work arises in order to understand the relevance and influence of various parameters associated to the combustion of forest biomass. The parameters analyzed in this study were the composition of the forest biomass, its moisture content, the excess of air of the combustion, the water’s dissociation, the particle’s diameter of the biomass to burn and the calorific value. For comparison purposes with natural gas the CO2 emissions inherent to combustion were also analyzed. The types of biomass used were Pinus pinaster’s biomass and Eucalyptus globulus’ biomass, which were chosen due to their sheer abundance in Portugal. The understanding of the previously enounced parameters was performed using a calculation methodology supported by the existent bibliography. With these parameters it was found, for Pinus pinaster’s biomass and for Eucalyptus globulus’ biomass, the flame’s adiabatic temperature, taking into account the variation in moisture content between 0% and 60%, the variation of excess of air between 0% and 100% and also considering a combustion with and without water’s dissociation. It was also observed the burning time associated to the combustion of Pinus pinaster’s biomass and Eucalyptus globulus’ biomass, which, besides moisture content, excess of air and water’s dissociation, the particle’s diameter of biomass varies between 1,0mm and 10,0mm. The results of the combustion of both types of biomass were compared in order to conclude which one of these two types of biomass is the most favorable for energy production. These results also include studies regarding the economic viability (€/kWh) and the CO2 emissions, when the combustion of the two types of biomass used is compared with the natural gas combustion.
The present work arises in order to understand the relevance and influence of various parameters associated to the combustion of forest biomass. The parameters analyzed in this study were the composition of the forest biomass, its moisture content, the excess of air of the combustion, the water’s dissociation, the particle’s diameter of the biomass to burn and the calorific value. For comparison purposes with natural gas the CO2 emissions inherent to combustion were also analyzed. The types of biomass used were Pinus pinaster’s biomass and Eucalyptus globulus’ biomass, which were chosen due to their sheer abundance in Portugal. The understanding of the previously enounced parameters was performed using a calculation methodology supported by the existent bibliography. With these parameters it was found, for Pinus pinaster’s biomass and for Eucalyptus globulus’ biomass, the flame’s adiabatic temperature, taking into account the variation in moisture content between 0% and 60%, the variation of excess of air between 0% and 100% and also considering a combustion with and without water’s dissociation. It was also observed the burning time associated to the combustion of Pinus pinaster’s biomass and Eucalyptus globulus’ biomass, which, besides moisture content, excess of air and water’s dissociation, the particle’s diameter of biomass varies between 1,0mm and 10,0mm. The results of the combustion of both types of biomass were compared in order to conclude which one of these two types of biomass is the most favorable for energy production. These results also include studies regarding the economic viability (€/kWh) and the CO2 emissions, when the combustion of the two types of biomass used is compared with the natural gas combustion.
Descrição
Dissertação de Mestrado em Engenharia Mecânica
Palavras-chave
Produção de energia , Biomassa florestal