往复旋转中空纤维膜处理脱脂奶水溶液

Research on skim milk ultrafiltration with a reciprocating rotating hollow fiber membrane module

采用一种往复旋转中空纤维膜超滤装置处理脱脂奶水溶液,考察了该膜过滤装置的结构参数、膜组件旋转参数以及料液的特征参数等对膜渗透通量衰减的影响。结果表明,旋转角速度越大,膜丝距中空轴轴心越远,往复旋转中空纤维膜的剪切强化作用越好;往复旋转周期的优化则需考虑如何使料液流场流速与膜丝转速之间的矢量迭加在膜表面产生的速度梯度更大,单纯增大或减小旋转周期均会弱化剪切强化的效果。在同样操作参数下,往复旋转方式比死端过滤及单向旋转方式的膜过滤更利于延缓膜通量衰减。

A novel dynamic filtration system of reciprocating rotating hollow fiber membrane was used to UF skim milk solution.The effects of the module＇s geometry parameters and rotating parameters as well as the characteristics of tested fluid on the decline of membrane permeate flux were investigated.The results indicated that a better shear enhancing efficiency could be obtained while the angular velocity and/or the radial distance of membranes from the central hollow shaft were increased.The greater vectors superposition of the flow field and the membrane rotating velocity,which was reflected on a relative greater velocity gradient,would be obtained once the reciprocating rotation cycle was optimized.Otherwise,simply increasing or decreasing the rotation cycle would weaken the efficiency of shear enhancement.With the same operating parameters,the reciprocating rotation filtration was more favorable in slowing the decline of membrane permeate flux than the dead end filtration or the uni-directional rotation filtration.