ULTRA LOW SULFUR DIESEL


Introduction

Ultra Low Sulfur Diesel (ULSD) is defined by the U.S. Environmental Protection Agency (EPA) as diesel fuel with a maximum sulfur content of 15 ppm (parts per million).

ULSD & EPA Regulations
The EPA has the authority to regulate diesel fuel and recently mandated a reduction in the sulfur content of diesel fuel from 500 ppm to 15 ppm, a 97% reduction. This mandate applies to all diesel fuel, diesel fuel additives and distillate fuels blended with diesel fuel for on-road use, such as kerosene. The mandate for on-road diesel fuel went into effect at the refinery level June 1, 2006; at the terminal level September 1, 2006; and at the retail level on October 15, 2006. The EPA mandate goes into effect for non-road, locomotive, and marine (NRLM) diesel fuel on June 1st, 2007.
The ULSD mandate requires not only that the sulfur content of on-road diesel fuel be drastically reduced by 2007, but also that emission controls on heavy-duty diesel engines be imposed to dramatically reduce emissions of nitrogen oxides (NOx), particulate matter (PM), and hydrocarbons (HC).

Label Requirements
The EPA mandate also includes label requirements that affect retailers of diesel fuel and manufacturers of diesel fuel additives.
Diesel fuel retailers are required to prominently display on the fuel pump either "15 ppm sulfur maximum" if the fuel meets the EPA standard or "500 ppm sulfur maximum" if the fuel does not meet the standard.
Diesel fuel additive manufacturers that comply with the EPA mandate are required to prominently display on the product label "This diesel fuel additive complies with federal low sulfur content requirements for use in diesel motor vehicles and nonroad engines." Diesel fuel additives that do not meet the EPA mandate should not be used with ULSD.

Advantages of ULSD

There are a number of advantages to using ULSD. ULSD will result in a reduction of acid rain and ozone depleting chemicals. The EPA estimates that ULSD will lead to improved air quality which will translate into a reduction in the incidents of asthma and lung cancer. ULSD is required on 2007 and newer diesel engines to allow fuel injection equipment to operate properly and prevent catalytic converter plugging. Catalytic converters can be damaged by as little as 30 ppm sulfur.

Disadvantages of ULSD

There are many disadvantages to ULSD even when taking into consideration the many environmental benefits.

(1) ULSD will substantially increase diesel fuel and engine costs. ULSD will cost approximately $0.05 to $0.09 more per gallon than Low Sulfur Diesel (LSD). Model year 2007 and newer diesel engines are required to use ULSD and, as a result, will cost approximately $8k more per medium-duty truck and $10k more per heavy-duty truck.

(2) ULSD contains lower energy content than LSD. ULSD has approximately 1% to 2% less BTU's than LSD. This translates into an additional $500 in fuel costs for every 100,000 miles driven.

(3) ULSD contains substantially reduced levels of lubricity. Natural lubricity is provided by oxygen and nitrogen compounds, aromatics, hydrocarbons, and sulfur. The refining process reduces many of these lubricity agents. Engine and fuel systems rely heavily on lubricity for proper operation. Insufficient lubricity leads to premature failure of wear-related fuel system components, including fuel pumps and injectors.

(4) ULSD has poor cold flow characteristics. This arises from the reduction in aromatic content, which increases the propensity of the fuel to gel/wax because aromatics keep wax crystals in solution. ULSD will, therefore, have a higher pour point and Cold Filter Plugging Point (CFPP). Lower aromatic content can also cause premature failure of some rubber components like gaskets and seals.

Conclusion

ULSD is the diesel fuel of the future, but the disadvantages of ULSD are great. These disadvantages can be overcome by treating ULSD with diesel fuel additives. E-ZOIL manufactures a number of diesel fuel additives specifically formulated to improve the cold flow characteristics and lubricity properties of ULSD including DIESEL AID, ARTIC POWER, ARTIC FLO, and CLEAN & LUBE. All E-ZOIL diesel fuel additives are ULSD compliant.

Ultra Low Sulfur Diesel Effective Dates

WHO WHAT  US  CALIFORNIA 
Refiners & ImportersImport/produce at least 80% ULSD for on highway use6/1/2006 
 Import/produce at least 100% ULSD for on highway use6/1/20106/1/2006
Downstream from Refineries through Fuel TerminalsFacilities that choose to carry ULSD must meet 15 ppm sulfur specification9/1/2006 
 All highway diesel must be ULSD10/1/20107/15/2006
Retail OutletsFacilities that choose to carry ULSD must meet 15 ppm sulfur specification10/15/2006 
 All highway diesel must be ULSD12/1/20109/1/2006