Some excerpted highlights follow:
"Technical Barriers to the Use of Ethanol in Diesel Fuel" Robert L. McCormick Center for Transportation Technologies and Systems National Renewable Energy Laboratory Golden, CO 80401-3393 "7th Annual National Ethanol Conference" February 27-March 1, 2002 San Diego, CA 19 page PDF > http://www.ethanolrfa.org/NEC02-McCormick.pdf Overview *Rationale *What is E-Diesel? *Main Technical Barriers *Flashpoint/Flammability Flashpoint defines e-diesel as a Class I liquid (like gasoline) for fire safety purposes Additionally, tank vapor space is flammable under some conditions Bottom Line for E-Diesel: *Other OEM Requirements *Stability and Water Tolerance Some additive suppliers indicate tolerance of up to 3% water. *Lubricity/Pump Wear *Pollutant Emissions *Fleet Demonstration Results *Summary - Blending Ethanol in Diesel - Some Typical Properties - Engine and Fuel Injection Equipment Manufactures Acceptance - Summary of Technical Barriers Performance of e-diesel in 2007 engines (equipped with EGR and exhaust treatment systems) using 15 ppm S diesel fuel will become an issue in the near future. ============== Background All diesel fuel injection equipment has some reliance on diesel fuel as a lubricant. The lubricating properties of diesel fuel are important, especially for rotary and distributor type fuel injection pumps. In these pumps, moving parts are lubricated by the fuel itself as it moves through the pump-not by the engine oil. Other diesel fuel systems - which include unit injectors, injectors, unit pumps, and in-line pumps are partially fuel lubricated. In these systems the..... Low lubricity fuel may cause high wear and scarring and high lubricity fuel may provide reduced wear and longer component life. Lubricity has sometimes been mistakenly compared to the viscosity, or thickness of a fuel. The following statement from Lucas..... Recent changes (1993 and beyond) in the composition of diesel fuel, primarily the need to reduce fuel sulfur and aromatic levels, and the common chemical process used to accomplish these changes (called hydro-treating) have inadvertently caused the removal of some of the compounds that provide lubricity to the fuel. According to Mr. Paul Henderson, ..... Typically, Number 1 diesel fuel (commonly referred to as kerosene), which is used in colder climates, has poorer lubricity than Number 2 diesel fuel. A 1998 review paper on fuel lubricity worldwide2 showed that diesel fuel in the US and Canada is some of the poorest lubricity fuel found in the entire world (see Figure 1 attached). Of the 27 countries surveyed, only Canada, Switzerland, Poland and Taiwan had poorer lubricity fuel than the US. With a mean fuel lubricity of just under the recommended specification of an HFRR wear scar diameter of 460 microns, fully 50% of the US fuel was found to be above that recommended by equipment manufacturers. These US data are with diesel fuel refined to meet the current EPA restriction of 500 ppm maximum sulfur specification. The severe hyrdrotreating required to reduce fuel sulfur to the new EPA 2006 specification of 15 ppm sulfur maximum will cause a further reduction in fuel lubricity compared to today's diesel fuel, and is of concern to engine and fuel injection equipment manufacturers. Lubricity Benefits Provided by Biodiesel For the HFRR, a lower wear scar indicates better lubricity. Biodiesel has been tested, at varying concentrations, with poor lubricity Number 2 and Number 1 diesel fuels representative of that on the market after 1993 (i.e. fuel refined to meet a 500 ppm maximum sulfur content). Lubricity Benefits Percent Biodiesel HFRR Scar (mm)* [MH: BD lube effectiveness via percentage %] Number 2 Number 1 0.0 536 - 671 - 0.4 481 10% 649 3% 1.0 321 40% 500 25% 2.0 322 40% 355 47% 20.0 314 41% 318 53% 100.0 314 41% 314 53% *Results provided by Stanadyne Automotive Corp. Stanadyne Automotive has stated: "....we have tested biodiesel at Stanadyne and results indicate that the inclusion of 2% biodiesel into any conventional diesel fuel will be sufficient to address the lubricity concerns that we have with these existing diesel fuels. From our standpoint, inclusion of biodiesel is desirable for two reasons...... The reasoning behind Stanadyne's support of 2% biodiesel makes biodiesel an ideal solution to the existing lubricity problem with diesel fuel-while supporting other environmental, energy security, and economic development initiatives. As EPA forces the further removal of sulfur from diesel fuel in 2006, which will undoubtedly worsen fuel lubricity, the concentration of biodiesel can be raised to that necessary to fully protect this future fuel as well. In fact, biodiesel tested higher in lubricity than any other diesel fuel tested at the Institute. The conclusions drawn by the researchers from Southwest Research Institute were: "Biodiesel fuels consisting of methyl esters of soybean oil had excellent scuffing and adhesive wear resistance that exceeds those of the best conventional diesel fuels." Read the full report: National Biodiesel Board "Lubricity Benefits" 4 page PDF > http://www.biodiesel.org/pdf_files/Lubricity.PDF ============== Vegetable based alternative diesel fuel lubricity additives were investigated in this study. Eleven low level biodiesel blends were tested with a low sulfur winter diesel fuel containing no other additives. The treat rate was 1vol%. Two different alcohols (methanol and ethanol) and four different oilseed crops, sunflower, flax/linseed, rapeseed and canola, were processed. A U.S. commercial biodiesel fuel additive was also obtained for testing. In the mid-90's, sulfur compounds were removed from diesel fuels due to concern over exhaust emissions. Unfortunately, the hydrotreating process used to reduce sulfur results in a less oily diesel fuel. This reduced lubricity in some cases may be causing injection pump failures and accelerated engine wear. To help remedy the problem, refiners are using industrial additives in low viscosity Canadian winter fuels. All of the 1vol% biodiesel blends raised the Lubricity Number of the unadditized, low sulfur reference diesel fuel above the M-ROCLE pass/fail value of 1.0. SCDC Fact Sheet/ Research Project Summary Lubricity Survey of Low-Level Biodiesel Fuel Additives Using the "Munson ROCLE" Bench Test SAE Paper # 1999-01-3590 Fall 1999 2 page PDF > http://www.scdc.sk.ca/pdf/fact5lubri.pdf ` Biofuel at Journey to Forever: http://journeytoforever.org/biofuel.html Biofuels list archives: http://archive.nnytech.net/ Please do NOT send "unsubscribe" messages to the list address. To unsubscribe, send an email to: [EMAIL PROTECTED] Your use of Yahoo! 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