From experimental data obtained bet

From experimental data obtained between 20 and 950 °C, correlations were proposed in order to estimate olivine minimum fluidization velocity and bed voidage. These relationships can be useful for industrial gasifier design. Moreover, hydrodynamic experiments were carried out in a circulating fluidized bed between 20 and 850 °C. Results showed that, under our operating conditions:• The trend of solids mass flow rate vs. gas velocity is of S-shape type;• the transport velocity Utr is not significantly affected by bed temperature and bed material inventory. It only seems to be proportional to terminal settling velocity Ut. The correlation proposed by Perales et al. (1991a) enables a good estimate of this characteristic velocity;• beyond Utr, the circulation mass flow rate mainly depends on bed material inventory and gas velocity. For the same bed inventory and gas velocity, it is independent of bed temperature;• beyond a certain gas velocity, the circulation mass flow rate levels off. The mass flow rate on this plateau is not affected by bed temperature but is strongly dependent on bed material inventory.Besides, results showed that key parameters for the solids flow rate control are combustor gas velocity and solids inventory. An increase in these parameters leads to higher circulation flow rates. However, the bed temperature and bed material nature showed no influence, neither on the transport velocity nor on the solids flow rate.