传质系数是决定气升式反应器传质特性的主要参数之一,文中介绍了一种新型的将陶瓷膜曝气系统与外环流反应器耦合的外环流膜反应器,考察了不同曝气气量,曝气压力,曝气方式以及曝气位置条件下反应器中体积传质系数的变化情况。结果表明,曝气气量,曝气压力,曝气孔孔径都能影响体积传质系数,孔径的影响尤为显著,采用膜微孔曝气,体积传质系数相比曝气头曝气提高近2倍。将膜管曝气和曝气头曝气耦合起来,可在获得良好气液循环的条件下有较大的气液接触面,从而优化气液传质。
Mass transfer coefficient is one of the important mass transfer parameters of the airlift reactor. A new type of external loop membrane reactor integrated with the ceramic membrane aeration system and the external loop reactor was put forward. For air-water system, the variation regularities of the volumetric mass transfer coefficients in this type of reactor were experimentally investigated under the conditions of different aeration volume, aeration pressure, aeration way and aeration position. The result indicates that many factors, such as aeration volume, aeration pressure, aperture of the sparger, have strong influence on the volumetric mass-transfer coefficient, of which the aperture influence is especially remarkable, and the volume mass-transfer factor is increased by nearly 100% when using the membrane instead of sparger. Aerating with membrane and sparger, a larger gas-liquid contact area was obtained in the situation of a good gas-liquid cycle, thus optimizing gas-liquid mass transfer.