It’s been 12 years since the on-road diesel supply pool transitioned to 15 ppm ultra-low-sulfur diesel fuel. As the Northeast heating oil supply pool prepares to do the same, here are 10 things we’ve learned since 2006.
- While ULSD is certainly a cleaner burning, more efficient fuel—especially whenblended with biodiesel—it is not a fix-all for every common fuel problem, nor does it come without its own set of operability concerns.
- The process used to remove sulfur also removes oxygen, nitrogen, and other functional elements. This yields a fuel that is more paraffinic, or waxy (to the detriment of its cold flow operability) and less stable in storage.
- Because higher sulfur fuel possesses natural lubricant qualities, ultra-low sulfur fuel can put more wear on equipment, meaning lubricity agents should be used in ULSHO to keep fuel pumps functioning optimally.
- Like biodiesel, ULSHO can be prone to increased levels of entrained water, and more susceptible to water and microbial contamination.
- Also similar to biodiesel, ULSHO is more soluble than high sulfur fuel, making it more liable to loosen filter-plugging deposits in tanks.
- Just because ULSHO is “cleaner” than traditional heating oil, it is not any less corrosive to tanks, pipes, and system components if left unprotected. In fact, much has been documented about excessive corrosive activity in ULSHO underground storage tanks. A NORA-funded study of 150 fuel samples pulled from storage tanks containing ultra-low-sulfur heating oil (ULSHO) found that moisture and microbial contamination, the primary sources of corrosion and fouling, should be a foremost concern to heating oil dealers and their customers. More than half of the samples collected tested positive for bacteria or fungus.
- A task force of industry leaders came together and formed the Clean Diesel Fuel Alliance, funding an independent study to determine the cause of accelerated corrosion in USTs containing ULSD. Conclusions from the study point to microbial generated acetic acid, possibly exacerbated by the introduction of ethanol into ULSD tanks due to switch loading. Switch loading is the practice of loading diesel into a cargo transport tank that had previously held ethanol gasoline. Ethanol, like ULSD, is corrosive by nature.
- As indicated by #7, while the physical properties of the fuel may be evolving, the supply, storage, and distribution chain down which it travels—where most fuel contamination occurs—remains the same.
- Sound storage, transportation, and general housekeeping practices—as well as additive treatment for lubricity, moisture control, cold flow performance, stability, and corrosion—are as essential as ever with ULSHO.
- It’s an exciting time for the heating oil industry. With the emergence of ULSHO and higher ASTM-approved blends of Bioheat® (B6 – B20), our industry has a compelling story to share with consumers. We can now offer a safer, cleaner, more efficient and more renewable alternative to natural gas. It’s up to each and every dealer to ensure that it’s more dependable.