Membrane fouling in a cross-flow ultrafiltration (UF) is investigated using a tubular membrane for three different feed solutions containing oil droplets and particles. The initial build-up of a highly concentrated fouled cake layer on the membrane surface results in sharp flux decline which acting as secondary filtration layer over the membrane surface. In the present work, the fouled cake layer resistance is quantified in terms of specific cake resistance (α), which depends strongly on the operating parameters. Cake resistance, α, calculated from experimental data using different models, is used as an operational indicator to quantify membrane fouling. Two sets of experiments are performed, first by operating tubular membrane as it is, and later by introducing a static helical turbulence promoter. Results showed that the influence of pressure and feed concentration on α is more important than that of feed temperature and cross-flow velocity. Oil droplets sizes, which vary mainly with temperature, play an important role in the interpretation of results. Droplets coalescence and flocculation of suspended particles and the aggregation of droplets on particles explain these variations. The cake layer is significantly reduced by using a novel static helical type turbulence promoter inside the tubular membrane module allowing operation at low pressure and low cross-flow velocity, thus, aid in reducing membrane fouling without significantly increasing energy consumption. Computational Fluid Dynamics (CFD) calculations of full Navier-Stokes equations are also performed to gain insight into flow hydrodynamics and for estimating shear stresses when the turbulent promoter is deployed. The result indicates that roughly 4-5 times higher shear stress on the membrane surface is generated depending on the applied cross-flow velocity. It potentially explains significant cake layer alteration with variations in specific resistance and corresponding flux enhancement as observed in experiments.

使用管状膜研究包含油滴和颗粒的三种不同进料溶液，对错流超滤（UF）中的膜污染进行了研究。在膜表面上最初形成的高度浓缩的结垢滤饼层会导致通量急剧下降，从而在膜表面上充当二次过滤层。在目前的工作中，结块的抗污性是根据比抗性（α）来量化的，该比抗性很大程度上取决于运行参数。从使用不同模型的实验数据计算得出的抗滤饼性α用作量化膜污染的操作指标。进行了两组实验，首先是直接操作管状膜，然后是引入静态螺旋湍流促进剂。结果表明，压力和进料浓度对α的影响比进料温度和错流速度的影响更为重要。主要随温度变化的油滴大小在结果解释中起着重要作用。液滴的凝聚和絮凝以及液滴在颗粒上的聚集解释了这些变化。通过在管状膜组件内部使用新型静态螺旋型湍流促进剂，可显着减少滤饼层，从而允许在低压和低错流速度下操作，从而有助于在不显着增加能耗的情况下减少膜污染。还可以对完整的Navier-Stokes方程进行计算流体动力学（CFD）计算，以深入了解流动流体动力学，并在部署湍流推进器时估算切应力。结果表明，取决于所施加的横流速度，在膜表面产生的剪切应力大约高4-5倍。它可能解释了显着的滤饼层变化，如实验中观察到的，其电阻率和相应的通量提高了。