低压膜处理工艺是传统工艺的新兴替代品 水的澄清过程。根据试点研究的结果，有几项 全面的处理设施最近已经建成，许多其他工厂目前也在建设中 正在施工或处于设计阶段。这些设施旨在 在导致最小膜污染的条件下运行。操作条件， 如渗透通量和横流速度，已被许多研究人员研究，以 尽量减少颗粒在膜表面的沉积。然而，这是有限的 有证据表明，这些最佳条件也对应于最大值或最大值 在设备的整个使用寿命内，对微生物病原体的排斥程度最低 膜系统。因此，操作条件对微生物的影响 需要对拒收进行研究，并确定最大拒收的最佳条件 微生物去除将有助于设计或运行全膜 系统本研究的目的是在实验室规模上对 小单元包含选定的中空纤维膜，以阐明 操作条件（跨膜压力、渗透通量、横流速度）发挥作用 关于微生物污染物的排除。选择的微生物是枯草芽孢杆菌 孢子和MS2噬菌体。 文献回顾显示，常见病毒替代物的清除率 不同研究中的MS2噬菌体可能存在很大差异，即使膜具有相同的结构 标称孔径。例如，孔径为0.2微米的MF膜显示为0.2微米 使用外部/内部操作模式删除MS2日志，但使用外部/内部操作模式删除1.2日志 内/外模式。使用相同孔径的MF膜进行的额外研究 0 2 um给出了MS2的1.9 log和lt1 log以及0.8 log清除率。因此 根据膜的标称孔径对其进行表征似乎不足以 解释微生物污染物通过 微滤（MF）和超滤（UF）膜。因此，我们的目标之一 本研究的目的是研究微生物转运的机制 通过MF和UF膜的污染物。膜孔径分布（PSD）为 被认为是理解微生物去除机理的一个重要因素 通过低压膜。 包括10个参考文献、表格和图表。

Low-pressure membrane treatment processes are an emerging alternative to conventional water clarification processes. Based on results obtained from pilot scale studies, several full-scale treatment facilities have been recently built, and many other plants are currently under construction or in their design phase. These facilities have been designed to operate under conditions that result in minimal membrane fouling. Operating conditions, such as permeate flux and cross flow velocity, have been studied by many researchers to minimize particle deposition on membrane surface. However, there is limited evidence demonstrating that these optimal conditions also correspond to maximum or at least adequate rejection of microbial pathogens throughout the operating life of the membrane system. Therefore, the effects of operating conditions on the microorganism rejection need to be studied and determination of optimal condition for maximum microorganism removal would be useful for designing or operating a full membrane system. The purpose of this study was to perform bench scale experiments with small units containing selected hollow fiber membranes to elucidate the role that operating conditions (transmembrane pressure, permeate flux, cross flow velocity) play on the rejection of microbial contaminants. Selected microorganisms are Bacillus subtilis spores and MS2 phage. A review of the literature reveals that removals observed for the common viral surrogate MS2 phage in different studies could vary widely even when the membrane has the same nominal pore size. For example, an MF membrane with a pore size of 0.2 um showed 0.2 log removal of MS2 with an outside/in operation mode but 1.2 log removal with an inside/out mode. Additional studies using MF membranes with the same pore size of 0.2 um gave 1.9 log, <1 log, and 0.8 log removals of MS2. Consequently, characterization of the membrane by its nominal pore size appears to be inadequate to explain the mechanisms responsible for the transport of microbial contaminants through microfiltration (MF) and ultrafiltration (UF) membranes. Therefore, one of the objectives of this study was to investigate the mechanisms responsible for the transport of microbial contaminants through MF and UF membranes. Membrane pore size distribution (PSD) is considered an important factor to understand the mechanism of microorganism removal by low-pressure membranes. Includes 10 references, table, figures.