A great deal of U.S. biodiesel industry focus remains on federal policy developments such as the status of the tax credit, the future of the renewable fuel standard (RFS) and how a new Trump administration might impact biofuels, but technical activities have always been—and will continue to be—critical to securing market growth. At the 2017 National Biodiesel Conference & Expo in San Diego this month, experts presented the latest information and data on efforts to grow biodiesel’s presence in the market through further improving its technical standing.

“The integration of biodiesel in the broader distribution system will help viability of this product in the broader market,” said Rod Woodford, manager of shipper relations and product quality for Explorer Pipeline Inc. Moving low-level blends of biodiesel such as B5 in the U.S. pipeline distribution infrastructure has long been considered crucial for widespread integration of biodiesel. Fellow panelist Rod Lawrence, the manager of quality control at Magellan Midstream Partners LP, said more than 2 billion gallons of biodiesel blended into U.S. diesel supplies annually over the past few years equates to more than 40 billion gallons of finished fuel product per year, when blended at 5 percent. Forty billion gallons of finished diesel fuel is a significant share of the overall U.S. market, so technical efforts are essential to accommodate this market demand.

In 2008, 33 technical issues were identified as needing to be addressed before integrating biodiesel in pipelines, Lawrence said. One long-term technical project to facilitate biodiesel distribution through the pipeline network has been gaining ASTM approval of higher trace levels of biodiesel in jet fuel. With earlier jet fuel standards set at just 5 parts per million (ppm) for trace amounts of fatty acid methyl esters (FAME), biodiesel advocates and distribution stakeholders have been successful in getting this limit bumped up to 50 ppm through ASTM channels after extensive testing of jet engines at 400 ppm. Doubling this approved amount to 100 ppm, however, is a major industry goal thought necessary to expanding biodiesel’s presence in the pipeline distribution infrastructure.

Woodford, part of the National Biodiesel Board’s Pipeliner Biodiesel Steering Committee—a working group involving Buckeye Partners LP, Colonial Pipeline Co., Explorer Pipeline, Kinder Morgan and Magellan Midstream Partners LP—said boosting allowance to 100 ppm from the current 50 ppm provides more room for error, which should be acceptable given the extensive testing done at 400 ppm did not pose operational problems in jet engines. Woodford said until a 100 ppm allowance, currently in the balloting process, is passed, the committee is working to establish provisional standards in the event that jet fuel tests at levels between 50 and 100 ppm. “We want to identify procedures and a path to follow when there’s not the opportunity to blend it down or any other remediation,” Woodford said.

Surveys conducted over the past three years to determine trace FAME levels in the nation’s jet fuel supply have demonstrated there is no issue with biodiesel-contaminated jet fuel beyond the 50 ppm limit, according to Woodford. While some B5 blends of biodiesel have been moved through pipelines—Kinder Morgan in Oregon for five years, Explorer Pipeline in Texas for four years, and Colonial Pipeline in Georgia for two years—none is commercially moved on segments that haul jet fuel. Thus, the surveys Woodford discussed were performed to establish a baseline prior to volumes of biodiesel blends being moved in jet fuel segments of the pipeline infrastructure. Woodford said the surveys showed a maximum level of trace FAME in jet fuel at 23 ppm—well below the 50 ppm limit.

“The vision of biodiesel is about to be realized,” Lawrence said. “We’ve run B5 on most major pipelines, and trials are starting to move B5 on jet segments.”

Fuel moves through pipelines in batches, and the comingling of fuel products between batches is known as transmix. Lawrence said there is a significant price difference for transmix, which can be bought at a discount and sent through a refining process known as fractionation to separate out the various comingled products. “Transmix processors don’t want biodiesel in the mix,” Lawrence said. “They say it fouls their heat exchangers.” He said questions exist to the validity of these claims about transmix with biodiesel causing fouling in the separation process so Magellan, which owns three transmix processing sites in Des Moines, Iowa, El Paso, Texas, and Odessa, Texas, is beginning a project in Des Moines to investigate these claims.

“We are going to blend biodiesel into transmix and process, sample, analyze and monitor the issue,” Lawrence said. “We want to be able to confirm or refute this problem.”

Earl Christensen, a chemist at National Renewable Energy Laboratory in Golden, Colorado, presented positive results from two studies conducted at NREL. The first was a recap of a B20 oxidative stability study performed more than a year ago and published by the Society of Automotive Engineers. The end result of this study showed there was no impact on the stability of B20 blends from passing through modern diesel engines’ high-pressure, high-temperature environment in common rail direct fuel injection systems. For more information about this study, click here. 

The other portion of Christensen’s presentation at the 2017 National Biodiesel Conference & Expo in San Diego covered an investigation of long-term B20 storage and readditization. Using 12 samples from 12 states, Christensen said the study, which aged the biodiesel samples at 110 degrees Fahrenheit to the induction period thresholds after which they were readditized with BHT, simulated nearly three years of long-term storage.

He said the study results bode well for long-term storage of B20. “After 32 weeks (simulating two and a half years), most samples were still on spec for six hours,” Christensen said, referring to the Rancimat test minimum of six hours in the ASTM specification of biodiesel blends between B6 and B20 used to ensure adequate oxidative stability of the fuel.

While Christensen said there is a point after which the fuel shouldn’t be used, if the biodiesel fuel is readditized soon after it shows signs of degradation, a B20 could easily be stored successfully for three years on remain on-spec.  

Steve Howell, the senior technical advisor for NBB, wrapped up the technical panel in San Diego by sharing technical updates on marine, power and heating oil markets to further biodiesel’s reach beyond on-road. Howell said this spring he expects the approval of up to 7 percent biodiesel in the marine fuel spec, ISO 8217. Furthermore, he said a working group has been established to pave the way for biodiesel blends in the on-ground gas turbine fuel specification, ASTM D2880. Howell said he expects significant progress on this front in the next year or two.

Finally, Howell said in fall 2016 ASTM passed the S15 grade of heating oil in ASTM D396, or ultra-low sulfur heating oil with 15 ppm, a measure particularly important for the Northeast U.S. in its objective to reduce greenhouse emissions from buildings by 80 percent in 2050.