부산대학교 도서관

The minimum fluidization velocity (U mf), bubble size characteristics, and tube-to-bed heat transfer coefficient (h c) of ilmenite particles are investigated at pressures up to 2000 kPa. The U mf was found to decrease with pressure for d sv ≥ 236 μm and remain constant for d sv ≤ 109 μm. U mf was compared to various Wen and Yu type correlations (R e mf = C 1 2 + C 2 Ar − C 1) with the Saxena & Vogel (1977) constants resulting in the best fit (AARD = 10.5%) for d sv ≤ 109 μm and the Chitester et al. (1984) constants resulting in the best fit (AARD = 6.4%) for d sv ≥ 236 μm. Pressure marginally effected bubble size relative to gas velocity, with the data fitting the Mori & Wen (1975) correlation best (AARD = 26.4%). The tube-to-bed heat transfer coefficient experienced a maximum with increasing gas velocity and marginally increased with pressure. The Molerus et al. (1995) correlation matched the atmospheric heat transfer data. Unlabelled Image • Small and dense ilmenite ore particles were fluidized at elevated pressures. • Influence of pressure on minimum fluidization was dependent on particle size. • Influence of pressure on bubble size was minor relative to gas velocity. • Surface-to-bed heat transfer coefficient was not greatly affected by pressure. • Several correlations were tested to predict key design parameters. [ABSTRACT FROM AUTHOR]