Abstract Compared to tubular membranes, spiral-wound membranes (SWM) cannot be operated at very high crossflow velocities due to mechanical instabilities of the module. We therefore applied a novel approach using custom-made microfiltration SWM modules to study the effects of crossflow velocities beyond the level currently applicable for commercial SWM. First, we used a modified industrial SWM (0.96 m) to measure flux and protein permeation spatially resolved within the limits of crossflow conditions applied in routine operation (maximum ΔpL of 1.3 bar). Secondly, we applied a short SWM (0.24 m) to assess the effect of extreme crossflow velocities with a corresponding ΔpL of up to 2.8 bar m−1. The goal was to investigate the effects of deposit formation reduced to the minimum, and thus, to measure the theoretically achievable improvement of flux and protein permeation even though this is currently not practicable. As key result, we found a critical crossflow velocity up to which a significant increase of protein mass flow could be achieved; beyond which, however, no further reduction in filtration resistance caused by deposit formation was observed. The filtration became independent of the transmembrane pressure. Based on these findings, more rigid modules could potentially improve the performance of SWM.

中文翻译：

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通过以极端错流速度运行的螺旋缠绕微滤膜的定制原型进行牛奶蛋白质分级

摘要 与管式膜相比，由于组件的机械不稳定性，螺旋缠绕膜 (SWM) 不能在非常高的错流速度下运行。因此，我们采用了一种新方法，使用定制的微滤 SWM 模块来研究超出当前适用于商业 SWM 水平的错流速度的影响。首先，我们使用改进的工业 SWM (0.96 m) 来测量通量和蛋白质渗透在常规操作中应用的错流条件限制内空间解析（最大 ΔpL 为 1.3 bar）。其次，我们应用短 SWM (0.24 m) 来评估极端横流速度的影响，相应的 ΔpL 高达 2.8 bar m-1。目标是调查沉积物形成的影响减少到最低限度，因此，测量理论上可实现的通量和蛋白质渗透的改进，尽管目前这是不切实际的。作为关键结果，我们发现了一个临界错流速度，达到该速度可以实现蛋白质质量流量的显着增加；然而，在此之后，没有观察到由沉积物形成引起的过滤阻力进一步降低。过滤变得独立于跨膜压力。基于这些发现，更刚性的模块可能会提高 SWM 的性能。过滤变得独立于跨膜压力。基于这些发现，更刚性的模块可能会提高 SWM 的性能。过滤变得独立于跨膜压力。基于这些发现，更刚性的模块可能会提高 SWM 的性能。