中空纤维膜组件结构对其膜蒸馏性能的影响

The effect of configuration on the performance of a hollow fiber membrane module

对一系列不同封装分率和不同膜面积的中空纤维膜组件进行了直接接触式膜蒸馏对比实验,并考察了操作方式对跨膜通量的影响。结果表明:提高封装分率可以明显降低沟流效应,使壳程流体分布趋于均匀,总体传质、传热效果得到改善,从而使跨膜通量提高,增幅可达40%以上;在组件封装分率较低时,热流体走管程更有利于跨膜传质。在进料状况不变的条件下,随着膜面积的增加,组件单位膜面积的跨膜通量明显降低,而总产量则有所增加。

Direct contact membrane distillation experiments with a series of hollow fiber membrane modules of different packing density or different membrane area have been conducted, and the effects of the operating mode on the trans-membrane flux were investigated. It was found that the distribution of the flow in the shell side became more uniform with increasing packing density, so that the channeling effect was weakened, the transmembrane flux was enhanced and the flux enhancement was more than 40 %. For lower packing densities, flow of hot feed through the tube side was more beneficial to mass transfer. With increasing membrane area, the pro- ductivity of the module increased to some extent whilst the trans-membrane flux became significantly lower.