It is widely understood that ultra low sulfur diesel is contributing to tank corrosion, filter plugging and increased wear to name a few.  According to the Battelle Memorial Institute Corrosion in Systems Storing and Dispensing Ultra Low Sulfur Diesel (ULSD), Hypotheses Investigation, acetic acid, a product of aerobic bacteria, is most likely the cause of aggressive corrosion.  It is also widely understood that eliminating water and particulate contamination is “food” for bacterial growth.  By removing the “food” bacteria has no life source and, therefore, cannot grow and spread.

Our recently redesigned diesel fuel conditioning and filtering system is for removing water and solid contamination from diesel fuel storage tanks.  By keeping these contaminants out of the diesel fuel storage tanks, algae, bacterial growth and acid cannot grow, thus keeping the fuel in pristine condition.

I recently came across the Chevron Diesel Fuels Technical Review that does an excellent job of making the case as to why diesel fuel conditioning is needed.

Here are some highlights:

Biogrowth

Untitled1“Even if the biocide effectively stops biogrowth, it still may be necessary to remove the accumulated biomass to avoid filter plugging. Any water bottoms that contain biocides must be disposed of appropriately because biocides are toxic. 89 The best approach to microbial contamination is prevention. The most important preventative step is keeping the amount of water in a fuel storage tank as low as possible, preferably at zero.”

“The presence of free water encourages the corrosion of metal storage tanks and provides the medium for microbiological growth.”

Cleanliness

“Inadequate lubricity is not the only cause of wear in diesel engine fuel systems. Diesel fuel can cause abrasive wear of the fuel system and the piston rings if it is contaminated with abrasive inorganic particles. Fuel injectors and fuel injection pumps are particularly susceptible to wear because the high liquid pressures they generate require extremely close tolerances between parts moving relative to one another. ASTM D 975 limits the ash content of most diesel fuels to a maximum of 100 ppm. (Inorganic particles and oil-soluble, metallo-organic compounds both contribute to the ash content; but, only inorganic particles will cause wear.) The U.S. government has a tighter specification of 10 mg/L (approximately 12 ppm) for all particulate matter. However, neither specification addresses particle size. While most fuel filters recommended by engine manufacturers have a nominal pore size of 10 microns,6 studies by the Southwest Research Institute reveal that the critical particle size for initiating significant abrasive wear in rotary injection fuel pumps and in high-pressure fuel injection systems is from six to seven microns.

However, as engine designs to reduce emissions result in higher fuel rail and injector pressures, the tighter clearances will have less tolerance for solids and impurities in the fuel. Consequently, some engine manufacturers are now specifying filters with pore size as low as two microns”

We’ve built several duplex filter assemblies for installation at existing power plants to improve inline diesel filtration, down to ß3[c]≥1000 3 micron efficiency.  The inline filtration and centrifuge technology originally installed is found not to be adequate to protect injectors and reduce wear.  In some cases, we use 10 micron absolute micro glass filters in the duplex assembly and install a smaller inline 3 micron micro glass filter at the turbine.

Acidity

“Organic acids in diesel fuel can also cause corrosive wear of the fuel system. While this may be a significant wear mechanism for high sulfur diesel, it is less significant for low sulfur diesel because hydrotreating to reduce sulfur also destroys organic acids. With the introduction of biodiesel fuel, there is some indication that organic acids could potentially increase.”

Removing water will reduce acidity substantially.  Contact us with your needs.  We will find the right solution for you!

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