Controling Diesel Emissions -
The Role of the Fuel Filter

Diesel emission regulations are driving changes in engine design, fuels and emission control technology. Fuel filters are often overlooked as part of the total emission solution, even though they protect fuel injection components essential to reduce emissions. High pressure common rail (HPCR) systems deliver fuel at pressures over 1500 bar. This allows the fuel injection system to control multiple injection events per combustion cycle.

With clearances of only a few microns, HPCR systems are relatively sensitive to solid contaminants and water. Thus, low concentrations of water and fine particles must be maintained. Since fuel may exhibit ISO Solid Contamination Codes greater than 24/23/19, filtration systems with 4 μm(c) particle removal efficiency greater than 99.8% may be needed.

Not only the engine, but also fuel itself is changing. Ultra-low sulfur diesel is replacing low sulfur diesel. Biodiesel usage is growing worldwide. Due to higher levels of surfactants, both fuels present increased challenges to fuel water separation. This may affect the life of HPCR components, unless appropriate contamination control measures are taken.

From this discussion, it is clear that fuel filtration plays an important role. Driven by evolving regulations, it is an exciting and challenging time for contamination control and fuel filtration.

Photo courtesy of Cummins Filtration Inc.

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