Forward osmosis (FO) is an emerging permeation-driven membrane technology that manifests advantages of low energy consumption, low operating pressure, and uncomplicated engineering compared to conventional membrane processes. The key issues that need to be addressed in FO are membrane fouling, concentration polarization (CP) and reverse solute diffusion (RSD). They can lead to problems about loss of draw solutes and reduced membrane lifetime, which not only affect the water treatment effectiveness of FO membranes, but also increase the economic cost. Current research has focused on FO membrane preparation and modification strategies, as well as on the selection of draw solutions. Unfortunately, these intrinsic solutions had limited success in unraveling these phenomena. In this paper, we provide a brief review of the current state of research on existing external field-assisted FO systems (including electric-, pressure-, magnetic-, ultrasonic-, light- and flow-assisted FO system), analyze their mitigation mechanisms for the above key problems, and explore potential research directions to aid in the further development of FO systems. This review aims to reveal the feasibility of the development of external field-assisted FO technology to achieve a more economical and efficient FO treatment process.

正向渗透 (FO) 是一种新兴的渗透驱动膜技术，与传统膜工艺相比，具有低能耗、低操作压力和简单工程的优点。FO 中需要解决的关键问题是膜污染、浓差极化 (CP) 和反向溶质扩散 (RSD)。它们会导致驱动溶质损失和膜寿命缩短等问题，不仅影响 FO 膜的水处理效果，还会增加经济成本。目前的研究主要集中在 FO 膜的制备和改性策略，以及绘制溶液的选择上。不幸的是，这些内在的解决方案在解开这些现象方面的成功有限。在本文中，我们简要回顾了现有外部场辅助 FO 系统（包括电、压力、磁、超声波、光和流量辅助 FO 系统）的研究现状，分析了它们对上述问题的缓解机制关键问题，并探索潜在的研究方向，以帮助进一步发展 FO 系统。本综述旨在揭示开发外场辅助 FO 技术以实现更经济、更高效的 FO 处理工艺的可行性。