Electromagnetic field (EMF) is a cost-effective, simple, and energy-efficient method for scale control in reverse osmosis (RO) systems. However, its effects on gypsum and silica scaling, as well as the underlying mechanisms, remain poorly understood. This study systematically investigates the effects of EMF treatment on gypsum and silica scaling in RO systems, utilizing synthetic brackish water and natural RO concentrate (ROC) from a desalination facility. For gypsum, EMF changes the crystal morphology, resulting in the formation of a porous, less compact scaling layer. It is more readily removed through hydraulic flushing (HF), enhancing scaling reversibility and water recovery. In the case of silica scaling, EMF promotes homogeneous polymerization in the bulk solution, producing larger silica particles that inhibit the formation of a dense, cross-linked gel layer on the membrane surface, mitigating flux decline. This study thus demonstrates EMF's effectiveness in controlling gypsum scaling in undersaturated feedwaters when combined with HF and in mitigating silica scaling under both HF and non-HF conditions for supersaturated feedwaters. These findings underscore EMF's versatility as a nonchemical approach for scale control in RO desalination and show its substantial potential to enhance membrane performance and operational efficiency in real-world water treatment applications.

Keywords: desalination; electromagnetic field; gypsum scaling; reverse osmosis; silica scaling.

电磁场（EMF）是一种成本低廉、简单且节能的方法，用于反渗透（RO）系统中的结垢控制。然而，其对硫酸钙和二氧化硅结垢的影响以及背后的机制尚不完全清楚。本研究系统地调查了EMF处理在RO系统中对硫酸钙和二氧化硅结垢的影响，使用合成苦咸水和来自海水淡化设施的天然反渗透浓缩液（ROC）。对于硫酸钙结垢，EMF改变了晶体形态，形成了多孔、较松散的结垢层。这种结垢层更易于通过液压冲洗（HF）去除，从而提高了结垢可逆性和产水量回收率。在二氧化硅结垢的情况下，EMF促进了溶液中均匀聚合反应，产生较大的二氧化硅颗粒，抑制了膜表面致密交联凝胶层的形成，减轻了流量下降的趋势。因此，本研究表明，在结合使用HF的情况下，EMF可以有效控制欠饱和进水中的硫酸钙结垢，并在HF和非HF条件下缓解超饱和进水中二氧化硅结垢的问题。这些发现强调了EMF作为一种非化学方法在RO海水淡化中结垢控制方面的灵活性，并表明其具有显著提升膜性能和实际水处理应用运行效率的巨大潜力。

关键词： 海水淡化；电磁场；硫酸钙结垢；反渗透；二氧化硅结垢。