关键词: 气升式, 反应器, 气含率, 局部气含率

Abstract: A new type of helical-flow airlift loop reactor (HALR) has been developed to strengthen flow, mixing and mass transfer performance in the annulus airlift loop reactor (AALR).The local gas holdups in riser of the 8.8 liters HALR as superficial gas velocities, the bottom gap —— the distance between the lower end of the draft tube and the bottom of reactor, the height of the reactor, and solid loading were experimentally studied and were compared with the ones in AALR for the system of air - water and air - water -K resin, within the superficial gas velocity of 0.47—2.31cm/s. The results show that for air - water system, at the lower superficial gas velocities, swirling sheets made the rising bubbles coalescence ; at higher superficial gas velocities, the bubbles were mainly broken by the swirl sheets. Axial gas holdup was increased as the increasing of axial height, the increasing amounts of axial gas holdup increases with the increasing of superficial gas velocity. For the system of air - water -K resin, the gas holdup increases with the increasing of the amounts of solids loading in the higher gas velocity, when the superficial gas velocity is small, gas holdup for the system of air-water is slightly higher than the ones for the system of three-phase. The prediction model of the axial gas holdup in riser has been proposed based on the experimental results,, there is a good agreement between calculated and experimental data and the average relative error of 12%.

Key words: air-lift, reactor, gas holdup, local gas holdup