Presentation: 2025 ND EPSCoR Annual conference 

October 21, 2025, NDSU Memorial Union, Fargo, North Dakota

Holistic Membrane Fouling Analysis for the Greater Grand Forks Regional Water Treatment Plant

A recent study was performed with the Greater Grand Forks Regional Water Treatment Plant (GGFRWTP) on operational impacts as a result of membrane fouling. During operation, membranes become fouled with inorganic, organic, and biological substances that degrade membrane performance over time and can result in premature membrane failure. Methods to mitigate membrane fouling range from pretreatment steps such as adding an antiscalant to posttreatment steps including physically and chemically cleaning the membranes. Antiscalants are critical to mitigate inorganic fouling, or scaling, as they bind to ions to promote bulk crystallization or reduce crystal growth rates. However, membranes will eventually become fouled and require replacement in order to continue normal operation. With these ideas in mind, the study analyzed two commercial antiscalants from different vendors and one antiscalant synthesized at UND in continuous pilot-scale, long duration tests to ascertain their effectiveness in mitigating scale formation on reverse osmosis (RO) membranes. After each test, the membranes were removed from the system and subjected to an autopsy to identify what foulants were present, where they were, and to what degree. These autopsies showed that the two commercial antiscalants both prevented scale formation equally well, but one showed significantly increased organic fouling resistance while the other showed none. The UND antiscalant was effective at the membrane head, but showed low organic fouling resistance. The membrane treated with no antiscalant showed the highest organic fouling resistance and low scale formation, altogether showcasing the potential for optimizations on antiscalant composition, concentration and dosage.