三相逆流湍动床气液传质性能的研究

Gas-liquid Mass Transfer in Three-phase Inverse Turbulent Bed Reactor

摘要:

由空气-水（清水/废水）-中空玻璃珠构成三相体系，在表观气速0.53～10mm·s^-1、固含率为0～0.3、表观液速0～0.2mm·s^-1的条件下，采用溶氧仪研究了三相逆流湍动床的气液传质性能，考察了操作参数和液体性质对液相容积传质系数k_La的影响。结果表明，在所试条件下，k_La为0.0456～1.414min^-1。k_La随着表观气速和表观液速的增加而增加，随着固含率的增加先增加后减小，0.05～0.08为反应器传质的最优固含率条件。液体性质对k_La有重大影响，高浓度模拟废水和工业废水中的kLa比清水中的k_La分别减小39.0%和50.9%。研究结果可为后续逆流湍动床废水生物处理过程分析与模拟提供传质基础数据。

Abstract:

The characteristics of gas-liquid mass transfer of three-phase system comprising air, tap water/wastewater, and hollow glass beads were studied in a laboratory-scale inverse turbulent bed reactor. The influence of operational factors and liquid property on volumetric liquid-phase mass transfer coefficient kLa was investigated under the conditions of superficial gas velocity (0.53mm·s^-1～10mm·s^-1), solid hold-up (0～0.3), and superficial liquid velocity (0～0.2mm·s^-1). The results showed that the coefficient value was 0.0456～1.414min^-1, which increased with superficial gas velocity and liquid velocity. The coefficient attained the maximum value at solid hold-up of 0.05～0.08. Compared with the coefficient value in tap water, that in synthetic wastewater and industrial wastewater is decreased by 39.0% and 50.9%, respectively. These data have provided a basis for the process analysis and mathematical simulation of inverse turbulent bed reactor.