This article presents a comprehensive analysis of the physicochemical and biological mechanisms underlying reverse-osmosis membrane fouling, along with the development and optimization of preventive strategies to enhance the operational stability of membrane systems. The relevance of this research is determined by the growing freshwater scarcity and the rapid expansion of desalination capacities, where over 65% of produced water is obtained through reverse osmosis. The work aims to integrate classical and modern non-invasive fouling diagnosis methods—from SEM-EDS, ATR-FTIR, and XPS to optical coherence tomography and online ATP/BGP sensors—to delineate four primary foulant types and identify key intervention points at the early stages of deposit formation. The novelty of the study lies in the design and optimization of cascade preventive strategies that combine fine physicochemical pretreatment, targeted chemistry, and adaptive control of cleaning and reagent dosing protocols via machine-learning algorithms. The proposed closed-loop control model—from deep diagnostics to automatic adjustment of operating parameters—enables a substantial extension of the maintenance interval and a reduction in the total cost per cubic meter of treated water. Key results demonstrate that: Inorganic fouling can be effectively suppressed by antiscalants and pH regulation, preventing irreversible carbonate and sulfate deposit formation; Organic deposits and colloidal particles are most robustly removed by combining surfactant-enhanced cleaning and membrane-surface modification with hydrophilic coatings; Biofouling is controlled through two-stage biocide protocols triggered by early signals from ATP sensors, which reduces cleaning costs and downtime to a critical minimum. Online monitoring of hydraulic and biological markers is integrated with trainable algorithms that flexibly adapt flow parameters and chemical protection in real-time. This article will appeal to specialists in membrane technology and desalination, as well as researchers and developers of reverse osmosis systems and preventive water quality management strategies.

reverse osmosis, fouling, membrane systems, preventive strategies

Abushaban, A., Salinas-Rodriguez, S. G., Kapala, M., Pastorelli, D., Schippers, J. C., Mondal, S., Goueli, S., & Kennedy, M. D. (2020). Monitoring Biofouling Potential Using ATP-Based Bacterial Growth Potential in SWRO Pre-Treatment of a Full-Scale Plant. Membranes, 10(11), 360–360. https://doi.org/10.3390/membranes10110360

Ahmed, M. A., Amin, S., & Mohamed, A. A. (2023). Fouling in Reverse Osmosis membranes: monitoring, characterization, Mitigation Strategies and Future Directions. Heliyon, 9(4), e14908. https://doi.org/10.1016/j.heliyon.2023.e14908

Ashfaq, M. Y., Al-Ghouti, M. A., & Da’na, D. A. (2019). Investigating the effect of temperature on calcium sulfate scaling of reverse osmosis membranes using FTIR, SEM-EDX, and multivariate analysis. The Science of the Total Environment, 703, 134726–134726. https://doi.org/10.1016/j.scitotenv.2019.134726

Feo-García, J., Pulido-Alonso, A., Florido-Betancor, A., & Florido-Suárez, N. R. (2024). Cost Studies of Reverse Osmosis Desalination Plants in the Range of 23,000–33,000 m3/day. Water, 16(6), 910. https://doi.org/10.3390/w16060910

Gao, Q., Duan, L., Jia, Y., Zhang, H., Liu, J., & Yang, W. (2023). Differences in the Effect of Mn2+ on the Reverse Osmosis Membrane Fouling Caused by Different Types of Organic Matter: Experimental and Density Functional Theory Evidence. Membranes, 13(10), 823–823. https://doi.org/10.3390/membranes13100823

Hoek, E. M. V., Weigand, T. M., & Edalat, A. (2022). Reverse osmosis membrane biofouling: causes, consequences, and countermeasures. Npj Clean Water, 5(1). https://doi.org/10.1038/s41545-022-00183-0

Kallapalli, N., & Basu, O. D. (2025). Surfactant-Enhanced Cleaning Solutions for Ceramic Membranes: A Comparative Study on Humic Acid and BSA Fouling. Membranes, 15(3), 73–73. https://doi.org/10.3390/membranes15030073

Kucera, J. (2019). Biofouling of Polyamide Membranes: Fouling Mechanisms, Current Mitigation and Cleaning Strategies, and Future Prospects. Membranes, 9(9), 111. https://doi.org/10.3390/membranes9090111

Lakner, J., & Lakner, G. (2025). Prediction of Expected Fouling Time During Transmembrane Transition in Reverse Osmosis Systems. Membranes, 15(6), 170–170. https://doi.org/10.3390/membranes15060170

Lee, S., Cho, H., Choi, Y., & Lee, S. (2023). Application of Optical Coherence Tomography (OCT) to Analyze Membrane Fouling under Intermittent Operation. Membranes, 13(4), 392–392. https://doi.org/10.3390/membranes13040392

Lin, Y.-L., Zheng, N.-Y., Gan, H.-Y., Chang, A.-X., Luo, H.-X., & Mao, Y.-J. (2021). Mitigating Silica Fouling and Improving PPCP Removal by Modified NF90 Using In Situ Radical Graft Polymerization. Membranes, 11(11), 904. https://doi.org/10.3390/membranes11110904

Pipich, V., Starc, T., Buitenhuis, J., Kasher, R., Petry, W., Oren, Y., & Schwahn, D. (2021). Silica Fouling in Reverse Osmosis Systems–Operando Small-Angle Neutron Scattering Studies. Membranes, 11(6), 413–413. https://doi.org/10.3390/membranes11060413

Pomerantz, N., Ladizhansky, Y., Korin, E., Waisman, M., Daltrophe, N., & Gilron, J. (2006). Prevention of Scaling of Reverse Osmosis Membranes by Zeroing the Elapsed Nucleation Time. Part I. Calcium Sulfate. Industrial & Engineering Chemistry Research, 45(6), 2008–2016. https://doi.org/10.1021/ie051040k

Rezaei, M., Alsaati, A., Warsinger, D. M., Hell, F., & Samhaber, W. M. (2020). Long-Running Comparison of Feed-Water Scaling in Membrane Distillation. Membranes, 10(8), 173–173. https://doi.org/10.3390/membranes10080173

Roth, R. S., Birnhack, L., Avidar, M., Hjelvik, E. A., & Straub, A. P. (2024). Effect of Solution Ions on the Charge and Performance of Nanofiltration Membranes. Npj Clean Water, 7(1). https://doi.org/10.1038/s41545-024-00322-9

Sanawar, H., Pinel, I., Farhat, N., Kruithof, J. C., & Vrouwenvelder, J. S. (2018). Enhanced biofilm solubilization by urea in reverse osmosis membrane systems. Water Res X, 1, 100004–100004. https://doi.org/10.1016/j.wroa.2018.10.001

Verbeke, R., Eyley, S., Szymczyk, A., Thielemans, W., & Vankelecom, I. F. J. (2020). Controlled chlorination of polyamide reverse osmosis membranes at real scale for enhanced desalination performance. Journal of Membrane Science, 611, 118400. https://doi.org/10.1016/j.memsci.2020.118400

Vrouwenvelder, J. S., Hinrichs, C., Van der Meer, W. G. J., Van Loosdrecht, M. C. M., & Kruithof, J. C. (2009). Pressure drop increase by biofilm accumulation in spiral wound RO and NF membrane systems: role of substrate concentration, flow velocity, substrate load, and flow direction. Biofouling, 25(6), 543–555. https://doi.org/10.1080/08927010902972225

Wang, J., Sim, L. N., Ho, J. S., Nakano, K., Kinoshita, Y., Sekiguchi, K., & Chong, T. H. (2022). Evaluation of Ceramics Adsorption Filter as a Pretreatment for Seawater Reverse-Osmosis Desalination. Membranes, 12(12), 1209. https://doi.org/10.3390/membranes12121209