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Kiln geometries were developed to reach homogeneous temperatures above 900 °C, during the firing process, aiming to improve the production process of the ceramists from Vale do Jequitinhonha (MG/Brazil). Techniques of reactive flow numerical solution using the software Ansys CFX have been used to foresee the behavior of the firings. Two types of catenary geometries, simple and robust, were studied, capable of being easily reproduced. The firewood used as an energy source in the current kilns and the developed ones, in this research project, favored the control of the kiln’s atmosphere during the firing, beyond being a source found with easiness for the ceramists. The results of the numerical simulations demonstrated the energy efficiency of the kilns and the level of temperature reached. Knowing well thermal and gas dynamic behavior, some parameters of the burning could be improved, aiming for a better quality of used ceramics. Kiln geometries were developed to reach homogeneous temperatures above 900 °C, during the firing process, aiming to improve the production process of the ceramists from Vale do Jequitinhonha (MG/Brazil). Techniques of reactive flow numerical solution using the software Ansys CFX have been used to foresee the behavior of the firings. Two types of catenary geometries, simple and robust, were studied, capable of being easily reproduced. The firewood used as an energy source in the current kilns and the developed ones, in this research project, favored the control of the kiln’s atmosphere during the firing, beyond being a source found with easiness for the ceramists. The results of the numerical simulations demonstrated the energy efficiency of the kilns and the level of temperature reached. Knowing well thermal and gas dynamic behavior, some parameters of the burning could be improved, aiming for a better quality of used ceramics. [ABSTRACT FROM AUTHOR]

Abstract: Sulphate scaling can have a disastrous impact on oil production in waterflood projects with incompatible injected and formation waters. This is due to precipitation of barium/strontium sulphate from the mixture of both waters and the consequent permeability reduction resulting in loss of well productivity. The system where sulphate scaling damage occurs is determined by two governing parameters: the kinetics coefficient characterising the velocity of chemical reaction and the formation damage coefficient reflecting permeability decrease due to salt precipitation. Previous work has derived an analytical model-based method for determination of two coefficients from laboratory corefloods during quasi-steady state commingled flow of injected and formation waters. The current study extends the method for determination of kinetics and formation damage coefficients from production well data consisting of barium concentrations in the produced water and of well productivity decline. We analyse production data for five wells from giant offshore field A, submitted to seawater flooding (Campos Basin, Brazil), and obtain values of the two sulphate scaling damage parameters. The two coefficient values were used for prediction of productivity decline for these wells. The values of kinetics and formation damage coefficients as obtained from either laboratory or field data vary in the same range intervals. These results validate the proposed mathematical model for sulphate scaling damage and the analytical model-based method “from lab and wells to wells”. [Copyright &y& Elsevier]