Clay treaters are usually placed upstream of a filter separator system to remove surface-active agents (surfactants), color, and additives from jet fuel. These unwanted contaminants may be present in fuel at the processing and refining levels or picked up from various transportation methods (trucks, ships, and pipelines that carry several types of petroleum products in addition to jet fuel). The contaminant compounds will accumulate and disarm the coalescer cartridge and reduce the water coalescing efficiency of the filter separator. Clay treaters provide a complete adsorptive system that removes the surfactant compounds, color, and additives and delivers treated fuel while also prolonging the cartridge life of the downstream filter separator.

The clay treaters may be used to remove soluble contaminants such as acids, waxes, gums, resins, asphaltenes, sludges, carbon residues, and colloidal particles from the lubricating, hydraulic, seal, quench, and insulating oils (in circuit breaker, transformers).

Clay treater elements can be supplied as bags or canisters. Canister elements are suitable for higher operating temperatures.