Reference from Authorities Regarding Long Term Diesel Storage
Technical Information Report #FTI-020399-5
Gregory A. Hagopian
The NFPA recommendation for stored diesel fuel maintenance states, "Diesel fuel has a storage life of approximately 1.5 to 2 years. Tanks should be sized so that the fuel is consumed within the storage life, or provision should be made to replace stale fuel with fresh fuel." This recommendation has been in place since the mid 1980's.
1991, Caterpillar, Inc. published, "Diesel Fuels and Your Engine". "Fuel stability additives are extensively used in diesel fuels to prevent oxidative breakdown of the fuel into gums and polymeric sediment during storage. But the fuel still has a finite storage life which is usually limited to about one year."
1994, University of Idaho scientists conducted tests to determine the timeline and percentage of degradation of stored diesel fuel #2. The result of this testing was that petroleum diesel fuel #2 degraded 26% after 28 days of storage.
1997, Factory Mutual Research Corporation, 1B1A9.AF Class 6063, "Fuel contamination is a potential cause of premature shutdown for standby engine generator sets and other diesel engine support functions. Contamination can commence as soon as the storage tanks are filled and will remain until the fuel is used"
1998, Technical Review, Diesel Fuels, Chevron Products Company. While storage stability should not be a concern for the majority of diesel fuel users, those who store diesel fuel for a prolonged period, i.e., one year or longer, can take steps to maintain fuel integrity . The actions listed below provide increasing levels of protection:
- Purchase clean dry fuel from a reputable supplier. Keep the stored fuel cool and dry. The presence of free water encourages corrosion of metal storage tanks and provides the medium for microbiological growth.
- Add an appropriate stabilizer that contains an antioxidant, biocide, and corrosion inhibitor.
- Use a fuel quality management service to regularly test the fuel, and as necessary, polish it - by filtration through portable filters - and add fresh stabilizer. This is common practice for nuclear power plants with back-up diesel powered generators.
- Install a dedicated fuel quality management system that automatically tests and purifies the fuel and injects fresh stabilizer.
Stored diesel fuel stability has declined significantly over the past two or three decades. The EPA is pushing to further reduce sulfur in distillate fuel, which will leave tomorrow's fuel less stable than today's. It is the responsibility of everyone designing or installing a diesel fuel storage tank to inform their customer, the end user, of the inherent problems associated with long-term storage of diesel fuel. By addressing this issue with the end user, prior to design or installation, you will be confirming to your customer that they are working with a company, or individual, that is well informed.
Incorporating a FTI automated diesel fuel maintenance system into the design and/or installation of a diesel fuel storage tank for an emergency power system or fire pump will assure clean fuel for when it is needed the most, in an emergency. Both the FT-I-3A series and FT-I-8A series automated stored diesel fuel maintenance systems comply with NFPA equipment requirement, " Listed ". Both are labeled FM APPROVED .
For more information regarding stored diesel fuel maintenance give us a call at (805) 459-1733 and we will put you in touch with your local Fuel Technologies International LLC Factory Representative.