EGSA Powerline Magazine:
"Corrosion Mechanism in Emergency Generators and Storage Tanks, and Corrosion Control"
The Electrical Generating Systems Association is the world’s largest organization exclusively dedicated to On-Site Power Generation, and includes most emergency generator manufacturers.
Mission Critical Magazine:
"Keep Generators and Storage Tanks Alive in the Wake of the Corrosion Crisis
Don’t discover the cost of corrosion the hard way"
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HOW CORROSIVE IS YOUR DIESEL?
3 Inexpensive Tests Will Tell You
100 % biodiesel holds 15 to 25 times more water than that of pure 100% diesel. This is because both water and biodiesel molecules are polar (they have a positive and negative charge to the molecule), so the water molecules are attracted to, and bond quickly to, the biodiesel molecule. Pure diesel is not polar, so water does not bond to it. The actual bonding mechanism of water to biodiesel is by a hydrogen bond. While weaker than a covalent or ionic bond, it still attaches multiple water molecules to a biodiesel molecule. The hydrogen atoms (positive charge) in the biodiesel bonds to the oxygen atom of water (negative charge). This is why pure biodiesel can hold 15 to 25 times more water than pure diesel, and why bonded water is so difficult to remove.
Because the water is bonded to the biodiesel molecule, it does not show up in the “clear and bright” visual test, nor does the water precipitate out to the tank bottom until the biodiesel blend hits saturation, at which time there is a high ppm water bonded to biodiesel. The only way to detect the water is by using a Karl Fisher (KF) titration (ASTM D6304), which uses titration and an electric current through the diesel sample to provides the energy necessary to break the hydrogen bond and release the water. The water can now be detected and measured. The test procedure is common and inexpensive. To date this test has not been used in the diesel storage industry, because before the use of biodiesel, water was not bonded to diesel, so most users are not aware of this test. It is critical that a Karl Fisher test be used to detect water levels in stored diesel.
Pat has been involved in diesel corrosion control since 2013, and has contributed to organizations such as the EGSA, the EPA, the Uptime Institute and BioFuels Digest. Pat is a lecturer in BioFuelNet Canada’s Advanced Biofuels Course, hosted on McGill University’s myCourses platform. http://biofuelnet.ca/advanced-biofuels-course/
If you have an emergency backup generator that cannot fail, contact us for information on the corrosion issue in the diesel infrastructure, and solutions on corrosion control