Análise via CFD de um combustor industrial utilizado no processamento térmico de pelotas de minério de ferro

• Ano de defesa: 2016
• Autor(a) principal: Bittencourt, Flávio Lopes Francisco
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal do Espírito Santo; BR; Mestrado em Engenharia Mecânica; Centro Tecnológico; UFES; Programa de Pós-Graduação em Engenharia Mecânica
• Palavras-chave em Português: Combustion; Thermal processes; Pellets; Ore; CFD; GLP; Pré-mistura; Processamento térmico; Fluidodinâmica computacional; Gás liquefeito de petróleo; Pelotização (Beneficiamento de minério); Minérios de ferro; Combustão; Engenharia Mecânica; 621
• Link de acesso: http://repositorio.ufes.br/handle/10/9742

Mining plays an important role in the Brazilian national economic scenario, with thepresence of several reserves. However, iron as it is extracted from these reserves, is notsuitable to be used directly in industry applications and therefore must be processed in orderto achieve agglomeration of fines and formation of iron ore pellets. Thermal processing ofpellets is widely used to provide reuse of the fines and to give pellets physical and metal-lurgical properties required for blast furnace operations. In order for these transformationsto occur, combustion of gas is used, providing heat and reducing potential to transformthe pellets. The problem lies in the complexity found in thermal processes of furnaces andindustrial combustors, which is associated with the lack of control commonly found in manyindustrial plants, resulting in excessive fuel expenses. In the present work, computationalsimulations were performed using the software ANSYS FLUENT to model a combustorpresent in an industrial environment. The fuel used is the liquefied petroleum gas (LPG).Flame characteristics such as temperature profile, flame length, product formation rateand turbulent flame speed were analyzed. Two geometries for the combustor were studied:one considering a free exit section and another accounting for a reduced output diametersection. The results showed that the abrupt reduction of the outlet diameter has directinfluence on the formation of the flame, making it thinner and narrower due to the actionof vortexes at the inlet and outlet region of the combustor. It was possible to determine thereaction zone thickness for both situations and its relationship with the turbulent flamespeed