Salinity limits magnetic field antifouling in water distribution systems

Magnetic field (MF) is a promising, eco-friendly approach for inhibiting fouling. However, its effectiveness remains controversial, with reports showing varying degrees of success. Water quality, particularly salinity, could be a critical factor influencing MF performance. The results indicated that MF reduced the total fouling by 10.3% to 54.6%, with efficacy diminishing as salinity increased. This was attributed to high salinity inhibiting MF’s ability to alter calcite to the more easily removable aragonite. Moreover, at lower salinities, microcrystals generated by MF treatment remain dispersed, thereby reducing the aggregation probability and minimizing the large particle deposition on pipeline surfaces. In contrast, high salinities led to denser microcrystals, increasing particle collision and deposition on pipelines. These findings help reconcile existing literature controversies by elucidating the salinity-dependent, continuous decay of MF efficacy, ultimately offering a robust, physics-based predictive framework for optimizing non-chemical fouling control in complex aqueous environments.