Concentration polarization and fouling are the most important issues to be addressed when designing ultrafiltration (UF) and microfiltration (MF) units for a specific application. Dynamic operation in UF and MF, such as backshock, is a method that allows mitigating adverse effects of polarization and fouling thus enhancing the separation performance. However, there is a trade-off between operational conditions (i.e. backshock duration time BS, the time between backshock TBBS, and flux) to achieve the desired effects. Herein, two hybrid mathematical models are developed and tuned to predict the behavior of the polarization layer in dynamic UF ($R_{adj}^2$ of 0.9185 and 0.9626, respectively). Both hybrid models can estimate the concentration on the membrane surface (e.g. 27 g/L when BS is 1.25 s and TBBS is 5 s). The results illustrate the intensifying effect of dynamic operation by decreasing the Molecular Weight Cut-off up to 74 times without decreasing the membrane flux. The performed experiments and developed models provide system insights for membrane systems design where the rejection could be enhanced and tunned according to operating conditions rather than the membrane pore size.

在为特定应用设计超滤 (UF) 和微滤 (MF) 装置时，浓度极化和结垢是最重要的问题。UF 和 MF 中的动态操作，例如反激，是一种可以减轻极化和结垢的不利影响，从而提高分离性能的方法。然而，在操作条件（即反震持续时间 BS、反震 TBBS 之间的时间和通量）之间存在权衡以实现所需的效果。在此，开发并调整了两个混合数学模型以预测动态超滤中极化层的行为（${\mathrm{电阻}}_{\mathrm{一种}dj}^2$分别为 0.9185 和 0.9626）。两种混合模型都可以估计膜表面的浓度（例如，当 BS 为 1.25 s 和 TBBS 为 5 s 时，为 27 g/L）。结果表明，在不降低膜通量的情况下，将截留分子量降低至 74 倍可增强动态操作的效果。进行的实验和开发的模型为膜系统设计提供了系统见解，其中可以根据操作条件而不是膜孔径来增强和调整截留率。