New voluntary biodiesel specifications earlier passed by the ASTM D2 Committee on Petroleum Products and Lubricants were officially sanctioned last week to provide more stringent controls for vegetable oils and animal fats used to create the alternative-fuel blend used in extreme climates that can result in gelling.
No. 1-B grade is the new blend operators can use along with additives for filters that have been clogged by No. 2-B, the new designation for the current standard. The National Biodiesel Board (NBB) said the choice of the No. 1-B and No. 2-B designations were selected to make the standard as similar as possible as the current mode of operation with No. 1 and No. 2 diesel fuel.
“The biodiesel industry took a proactive stance to improve the standards governing America's Advanced Biofuel,” said Joe Jobe, CEO of NBB. “For the large majority of biodiesel users, the current standard along with conventional industry management practices allow for biodiesel blend use year-round, even in extreme climates.”
The No. 1-B grade was developed to address cases when the new Ultra Low Sulfur Diesel (ULSD) mandated by the EPA resulted in unexpected filter clogging above the cloud point of the finished blend, which NBB said mostly occurred with low-aromatic No. 1 type diesel blends. NBB added that the voluntary No. 1-B grade maintains the same parameters as the current standard, and provides more stringent controls for minor components that have been implicated in rare filter clogging in the field with ULSD. Monoglycerides were chosen as a surrogate for all minor components and are limited in the new No. 1-B grade to 0.40 percent mass maximum, and the Cold Soak Filtration Time is limited to 200 seconds year around.
“We are committed as an industry to being proactive so that the end user gets the best product possible,” said Kyle Anderson, technical projects manager at NBB. “As part of our on-going commitment to improving the standards and fuel quality, we will continue to investigate these rare phenomena and may propose further changes over time as more data and improved test methods become available."
The No. 1-B specification passed the ASTM D2 Main Committee on Petroleum Products and Lubricants via electronic ballot adjudication of negatives from the December 2011 ASTM D2 meeting. The handling of the negatives was reviewed and approved by the ASTM Committee on Standards at a meeting late last week. The modified version of ASTM D6751 containing the new No. 1-B grade will be released for public use later this summer after editorial review and typesetting.