In the integrated steel industries the sintering process plays an important role furnishing raw material to the blast furnace. In this work, a computational simulation of the sinter process is developed that is able to predict the most important phenomena within the sintering bed. The model is based on the multi phase concept with multiple components described by conservation equations of each component coupled with the momentum, chemical reactions and heat transfer. The model validation was carried out comparing the model predictions with averaged industrial data and local temperature measurements within the sinter strand. The model predictions presented good agreement with the averaged values measured on the industrial sinter process.

In this paper a model based on transport equations is proposed to study the weldability of low alloy ferritic steels T/P23 and T/P24. The model was numerically implemented by using the finite volume method (FVM) in an open source computational code to simulate the influence of the heat input, base metal thickness and preheating temperature on the thermal evolution and the cooling rate during the welding process. Meanwhile, it was possible to evaluate qualitatively the microstructure at the heat affected zone (HAZ) of these steels when a single weld bead was deposited on their surface and calculate the maximum hardness reached at this region. A double-ellipsoid heat source model for power density distribution was used in order to obtain a good estimate of the cooling rate and evolution of the fusion zone (FZ). The results are discussed and good agreement between experimental and simulated results was obtained for temperature distribution

This paper deals with the numerical simulation of the new technology of gaseous fuel utilization on the sintering process of iron ore. The proposed methodology is to partially replace the solid fuel(coke breeze) by steelworks gases. A multiphase mathematical model based on transport equations of momentum, energy and chemical species coupled with chemical reaction rates and phase transformations is proposed to analyze the inner process parameters. A base case representing the actual industrial operation of a large sintering machine is used with thermocouples inserted into the sintering bed to record the inner bed temperatures and compare with model predictions in order to obtain model validation and parameters adjustment. Good agreement of the temperature pattern was obtained for the base case and thus, the model was used to predict four cases of fuel gas utilization: a) 2% of the wind boxes inflow from N01-N15 wind boxes of natural gas(NG), b) same condition with coke oven gas(COG), c) same condition with blast furnace gas(BFG) and d) mixture of 50% COG and 50% BFG. The model predictions indicated that for all cases, except only BFG, the sintering zone is enlarged and the solid fuel consumption is decreased about 8kg/t of sinter product. In order to maximize the steelworks gas utilization it is recommended the use of mixture of COG and BFG with optimum inner temperature distribution

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O presente trabalho apresenta um modelo matemático capaz de prever a influência das propriedades de amolecimento e fusão da mistura de matérias primas na cinética de formação dos constituintes cálcio ferrita e dicálcio ferrita na sinterização de minério de ferro. O modelo é baseado na solução simultânea das equações de transporte de Momentum, energia e espécies químicas formuladas para sistemas multifásico e multicomponente, acoplado à cinética de reações químicas e transformações de fases que ocorrem no interior da esteira de sinterização. A solução numérica é obtida utilizando-se o método de volumes finitos validado com resultados de monitoramento de uma planta industrial de sinterização. Os resultados indicam que as temperaturas de início de amolecimento, contração volumétrica e intervalo de fusão são os principais parâmetros a serem controlados visando obtenção de formação de fase líquida que confere resistência mecânica e redutibilidade adequadas ao sínter. Neste estudo confirma-se que matérias primas com alto ponto de amolecimento e fusão combinado com alta contração volumétrica e grande intervalo de temperatura da zona pastosa podem diminuir até 20% o volume de fase líquida formada e, consequentemente, diminuir em mais de 30% a formação de cálcio ferritas o que deterioraria consideravelmente as propriedades finais do sínter.