三相连续环流反应器中氧的液相传质过程

在空气-水-玻璃珠三相连续操作环流反应器中，利用动态溶氧方法研究了表观气速(Ug=0.01~0.13 m/s)、进料浆速(USL=0.001~0.011 m/s)、浆相质量固含率(es=0~30%, w)和固相颗粒大小(dp=59, 200 mm)对环流反应器内氧的液相传质性能的影响. 结果表明，在考察范围内，环流反应器传质系数随表观气速增大而增大，受进料浆速变化的影响较小，随浆相固含率增大呈现先增大后减小的趋势，但在高固含率下(es≥10%, w)的影响不显著；随固相颗粒粒径增大而减小. 同时得到了液相体积传质系数的经验关联式.

Oxygen Mass Transfer in the Liquid Phase of a Three-phase Continuous Loop Reactor

Liquid phase oxygen mass transfer characteristics in a three-phase continuous loop reactor were studied by a dynamic oxygen dissolution method with glass beads (dp=59, 200 mm; rs=2460 kg/m3) as the solid phase, air as the gas phase and tap water as the liquid phase, respectively. Liquid phase oxygen mass transfer coefficient (kLa) was measured in the range of superficial gas velocity (Ug=0.01~0.13 m/s), superficial slurry feeding velocity (USL=0.001~0.011 m/s), solid holdup (es=0~30%, w) and two different particle diameters. It is found that kLa value increases with increasing superficial velocity, but decreases with increasing particle size. It is also demonstrated that variation of USL has no significant effect on kLa in the range of the investigated operation conditions. And a maximum kLa is found when the solid holdup increases at given Ug and USL, but the effect of solid hold-up is negligibly small when es is larger than 10%(w). Finally, an empirical correlation of kLa is presented for designing such type reactors.