Ultra-Low Sulfur Diesel
For those of you who have waited, the day has finally arrived. Ultra-Low Sulfur Diesel (ULSD) is here.
In an attempt to clear up some of the misconceptions and misinformation on the EPA and ASTM requirements for ULSD I will try to set the record straight.
You will first notice that this is very clear fuel, with possibly a very light amber or green tint to it. When fresh it has very little if any odor. It may also feel a little thinner and less oily to the touch.
The EPA requires that as of June 1, 2006, 80% of diesel fuel refined and sold for on-highway use be delivered to the distribution network at 15 parts per million (ppm) or less of sulfur.
As of October 1, 2006 80% of all fuel delivered for on-highway use must be 15ppm or less of sulfur.
The 80% requirement is designed to accommodate some older refineries that would otherwise be forced off-line and to offer a marketing channel for LSD. It will be problematic for to try and order this product for use on regular basis due to storage tank constraints.
Refiners and Distributors are under no obligation to notify you when they begin delivering this product. The regulations for Low Sulfur Diesel and Ultra- Low Sulfur Diesel limit the maximum amount of Sulfur in fuel. There are No requirements regulating minimum levels of sulfur in fuels sold.
During the period between June 1 and October 1 distributors have the opportunity to sell-through or purge their inventories of the current Low Sulfur Diesel (LSD).
Due to a lack of stored product in the US marketplace, there is little if any inventory to purge, therefore it is very likely that you are already receiving ULSD.
In the US we have traditionally used #1 diesel, kerosene, or Jet A to blend with or ?cut? #2 diesel for winter use. In many cases, high sulfur #1, kerosene, or Jet A has been used for this purpose.
Because of the very low 15ppm threshold for diesel it will now be necessary for the refiners to create and distribute an Ultra-Low Sulfur #1 fuel to primarily be used for winter blending. Because of a lack of storage facilities, there is likely to be a shortage of this product available this fall.
Take note: It is illegal to deliver fuel containing more than 15ppm of sulfur into any 2007 or later model on-highway diesel fueled vehicle.
Many refiners have been delivering fuel containing less than 50ppm of sulfur for some time now as they have tested and ramped up their refineries to produce ULSD by June 1. Many customers have been on ULSD or nearly ULSD for the last several months. It has been very inconsistent up to this point.
There are some suppliers who have been spreading the idea that after June 1 only Ultra-Low Sulfur #1 diesel will be available. This is false.
The primary diesel fuel is and will continue to be #2 diesel. Those customers who have been using this ULSD #1 to operate equipment requiring ULSD will find it more difficult to find #1 ULSD and if available it will be far more expensive than the #2 ULSD.
Also #1 fuel offers significantly less Btu?s (energy) per gallon, less lubricity, less viscosity. You are paying significantly more and getting significantly less.
In the US the EPA regulates only sulfur content. The other specifications for diesel fuels are determined by the American Society for Testing of Materials (ASTM).
One of the biggest concerns with ULSD is the severe reduction in Lubricity resulting from the removal of the sulfur.
The current method for measuring Lubricity worldwide is known as High Frequency Reciprocating Rig (HFRR). This testing device uses vibration between metal surfaces to determine the lubricating characteristics of fluids.
With HFRR a lower number is better.
High Sulfur #2 diesel provides a HFRR of 300-350
Low Sulfur #2 diesel provides a HFRR of 350-390
Ultra-Low Sulfur #2 diesel provides a HFRR of 600-800
Ultra-Low Sulfur #1 diesel provides a HFRR of 700-900
The Engine Manufacturers Association (EMA) has determined that it can accept an HFRR of 460 or lower. (They would greatly prefer 400 or even lower)
The European Union (EU) has determined that they will accept an HFRR of 460 or lower for their fuels.
The ASTM has determined that in the interest of keeping refiners costs as low as possible that it knows better than the engine manufacturers and the rest of the world what engines need and has therefore set its standard at HFRR 520.
This standard opens up the possibility of warranty problems with manufacturers able to claim that available fuel does not meet their warranty requirements.
When you consider that Cetane in the US does not meet engine manufacturer?s requirements, that Dissolved water content does not meet the requirements, suspended solids does not meet the requirements, and now with lubricity not meeting the requirements, you have to wonder how these specifications are being determined and why this is happening.
Some additional considerations:
ULSD forms gums, varnishes, and carbon deposits more easily and quickly than LSD.
ULSD shows a tendency to deteriorate or oxidize more quickly than LSD.
ULSD is the result of a process of known as severe hydro-treating. This process shows a tendency to cause the fuel to be harder to treat for cold flow improvement. It may require more #1 fuel or more or different additives to meet cold weather needs.
It is likely that there will some temporary disruptions or spot shortages of product during the changeover process.
ULSD is more hygroscopic than LSD has been. This tendency to hold more dissolved water will have negative effects on cold weather operations and will increase corrosion.
ULSD will be significantly more expensive.
Energy Technology Group, Inc. has a complete line of products to bring fuel to level meeting or exceeding the engine manufacturer's requirements, to control problems with fuels, improve cold weather operations, protect engines and fuel systems, reduce emissions, and to improve fuel economy.
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