缩放型导流筒气升式内环流生物反应器流体力学与传质特性

Hydrodynamics and Mass Transfer in an Internal Loop Airlift Bioreactor with a Convergence-divergence Draft Tube

从气相含率、液体循环速度和体积氧传质系数方面研究缩放型导流筒气升式内环流生物反应器内的流体力学与传质特性。实验结果表明，与传统圆柱形导流筒相比较，缩放型导流筒气相含率和体积氧传质系数分别提高８％和１０％以上．气相含率和体积氧传质系数随固含率的增加而提高，液体循环速度随固合率的增加而减小;;同一内管反应器随介质粘度的增加，体积氧传质系数减小，此外还在Ｈｉｇｂｉｅ穿透理论和Ｋｏｌｏｍｏｇｏｒｏｆｆ各向同性理论的基础上建立了体积氧传质系数与操作条件及管结构参数之间的关联式。

Hydrodynamics and mass transfer in an internal loop airlift bioreactor with aconvergence-divergence draft tube were studied in terms of gas holdup, liquid circulation velocity andvolumetric mass transfer coefficient. The bioreactor consists of one conventional draft tube and threeconvergence-divergence draft tubes. It was shown that gas holdup and volumetric mass transfercoefficient of convergence-divergence draft tubes were 8% and 10% higher than those of conventionaldraft tube, respectively. At the same superficial gas velocity, gas holdup and volumetric mass transfercoefficient were increased with solid loading, whereas liquid circulation decreased with solid loading.Volumetric mass transfer coefficient was decreased with CMC concentrations under the same draft tube.Based on Higbie penetration theory and Kolmogoroff theory of isotropic turbulence, the correlation forcalculating volumetric mass transfer coefficient was obtained.