Impact of a liquid spray on flow characteristics of carbonized slag in a hot fluidized bed

The gas-solid fluidized bed with liquid spray has been used in the industrial processing. Investigating the flow behaviors is crucial for optimizing the fluidized bed reactor. This research experimentally investigated the effects of gas velocities, temperature, height-to-diameter ratios, and solid-liquid ratios on flow characteristic in a spray-fluidized bed. The findings revealed that as the gas velocities increased, the standard deviation of pressure pulsation exhibited an upward trend, while the fluidization index initially decreases before subsequently increasing, achieving optimal fluidization quality at a velocity of 0.25 m/s. As the temperature rises, the trends of the pressure pulsation show contrasting trends before and after adding liquid, with the lowest fluidization index observed at 510 °C. An increased height-to-diameter ratio contributes to a rise in the pressure pulsation, and the fluidization index first decreases and then tends to be stable. Additionally, as the solid-liquid ratios increase, the pressure pulsation also rises after adding liquid, and the entrainment rate was negatively correlated with the average particle size of the remaining particles in the bed. The findings elucidate liquid-phase effects on gas-solid dynamics, directly informing strategies to optimize chlorination efficiency of the carbonized slag and improve reactor stability.