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The aerodynamics of particles and heat transfer of gas-to-particles in a two-dimensional spouted bed (2DSB) with draft plates are investigated by the discrete element method (DEM). The physical properties of the particles are similar to those of shelled corn. The calculated minimum spouting velocity and pressure drop agree well with the empirical correlations proposed by Kudra et al. The particle circulation rate increases when the friction coefficient decreases or the separation height increases. The draft plates can reduce the minimum spouting velocity and pressure drop. They also increase the maximum spoutable bed height. The effect of taking out the draft plates on the spouting phenomenon is investigated. The mixing of a 2DSB without draft plates of 10000 particles is better than that of 26000 particles. In our simulation, the gas-to-particle heat transfer is investigated. The Ranz–Marshall correlation and the correlation of Sartori et al. are applicable in the spout region and the downcomer region, respectively. The gas-to-particle heat transfer occurs mainly in the central or spout region, as reported by Freitas and Freire. [ABSTRACT FROM AUTHOR]

This paper reports a study of the phase evolution induced by mechanical milling of a mixture of industrial grade La2O3, SrCO3 and Mn3O4 powders under a humid atmosphere. In this milling, no media balls were employed and the mechanical activation was applied through friction among particles in the powder mixture. Under humid atmosphere (relative humidity 70% at 25°C), X-ray diffraction peak intensities of La2O3, SrCO3 and Mn3O4 decreased, and the specific surface area of the powder mixture increased at the early stage of the milling (less than 10 min). In further milling, the perovskite strontium-doped lanthanum manganite (LSM) started to appear. Differential thermal analysis suggests that the present mechanical activation brought about the decomposition of SrCO3. Single-phase LSM was obtained by annealing of the milled powder mixture at a relatively lower temperature of 900°C and its particle size was about 100 nm. The present mechanical milling resulted in considerably lower contamination release from milling media. [ABSTRACT FROM AUTHOR]