A nanofiltration system experienced fouling after changing their water source from surface water to well water and wanted to determine the cause. Through Chromatic Elemental Imaging (CEI), it was determined that the foulant material had an underlying layer of iron oxide and iron phosphate beneath a layer of manganese and calcium. Additionally, colloidal sulfur particles were identified above both foulant layers. From this analysis, the system reevaluated its pretreatment and was able to clean the elements in their system.

Rapid fouling in the third stage of a reverse osmosis system was causing frequent system shutdowns and a loss in productivity. An element was removed for analysis and was coated with a black colored substance. CEI identified not only manganese, which is associated with black-colored foulant material, but an underlying layer of calcium sulfate, a flux-reducing scale. Particles of calcium and silica were also identified, randomly dispersed above the calcium sulfate layer. Based on these results, a sulfate-targeting antiscalant was put online, preventing fouling.

A reverse osmosis system using an untargeted antiscalant was experiencing fouling in their last stage, resulting in a lower-than-normal flow. CEI of the membrane surface revealed three distinct scales: silica, calcium carbonate, and calcium sulfate. Imaging also revealed that silica was present below the calcium carbonate and calcium sulfate layers. With this information, the system changed to an antiscalant that targeted both silica and calcium carbonate, and the fouling issue was resolved.

An engineering firm provided a sample harvested from a reverse osmosis element used for purifying leachate from a landfill for analysis. CEI of the sample identified a layer of barium sulfate across the entirety of the membrane surface. Additionally, a layer primarily composed of iron oxide and organics (high carbon) was also detected above the barium sulfate. Randomly dispersed colloidal silica was also present in the top layer of foulant material. Based on these results, it was determined that using a cleaner that targeted sulfates, all of the foulant material would be removed from the membrane surface, as the underlying foulant layer was composed of barium sulfate.

Water from a wastewater treatment facility was fed into an ultrafiltration module, followed by cartridge filters, and finally, to a reverse osmosis system. Suddenly, the cartridge filters began to rapidly foul, causing shutdowns. It was determined that an equipment failure had occurred in the ultrafiltration module, and the system wanted to ensure that no bypass from the cartridge filters had caused fouling of the reverse osmosis system. Analysis of the membrane determined that fouling had occurred. The foulant was identified as a combination of calcium phosphate, organics, silica, and diatoms (algae with silica shells). The failure in the ultrafiltration module was fixed, and the reverse osmosis elements were successfully cleaned.