Membrane fouling is an inevitable problem in the process of using membrane technology to filtrate microalgae. In the present study, a uniform shearing vibration membrane (USVM) system was proposed and utilized in algae filtration. USVM is a uniform circular motion whose induced shear rate is constant, which is more conducive to the mitigation of fouling. In the filtration experiments, as the frequency increased from 1 to 5 Hz, the membrane fouling decreased obviously. When the frequency is 5 Hz, USVM can filtrate algae with a constant flux and less membrane fouling, and few algae deposited on the membrane. Based on “extended Derjaguin, Landau, Verwey, Overbeek” (XDLVO) theory, the interaction force acting on algae and membrane was calculated to explain the mechanism that USVM can filtrate algae stably at the frequency of 5 Hz, and why the increased frequency could effectively mitigate membrane fouling. At 5 Hz, the initial lift force was 0.123 nN, the total interaction force was the repulsive force, and thus the algae could be prevented from being deposited on the membrane to reduce the membrane fouling. As the frequency decreased, the initial lift force and total interaction force declined, which could not effectively prevent algae deposition.

在使用膜技术过滤微藻的过程中，膜结垢是不可避免的问题。在本研究中，提出了一种均匀的剪切振动膜（USVM）系统并将其用于藻类过滤。USVM是均匀的圆周运动，其诱导的剪切速率是恒定的，这更有助于减轻结垢。在过滤实验中，随着频率从1 Hz增至5 Hz，膜污染明显降低。当频率为5 Hz时，USVM可以以恒定的流量过滤藻类，减少膜污染，并且几乎没有藻类沉积在膜上。根据“ Derjaguin，Landau，Verwey，Overbeek的扩展”（XDLVO）理论，计算了作用于藻类和膜的相互作用力，以解释USVM在5 Hz频率下稳定过滤藻类的机理，以及为什么增加频率可以有效减轻膜污染。在5 Hz时，初始升力为0.123 nN，总相互作用力为排斥力，因此可以防止藻类沉积在膜上，从而减少膜污染。随着频率的降低，初始升力和总相互作用力均下降，这不能有效地防止藻类沉积。