Course: BFM 202 Biodiesel Production

Lecture

Fuel Properties and Cold Weather Performance
Credits
BFM 202 Biodiesel Production Unit 1 Reading has been adapted from "ENGY 131 Unit 1 Commentary: What is biodiesel?" by Southeastern Illinois College.

ENGY 131 Biodiesel Production course content by Southeastern Illinois College is licensed under a Creative Commons Attribution 3.0 Unported License. Except where indicated otherwise.

Unit 7 Fuel Properties and Cold Weather Performance

One of the most significant challenges for biodiesel is cold weather management of the fuel. At colder temperatures both petrodiesel and biodiesel can thicken and prevent proper fuel flow which negatively effects fuel injectors, pumps, and engine performance. This performance is normally monitored by pour point, cloud point, and cold filter plug points. Chemical composition of the feedstock determines a fuel's cold-flow properties. The cloud point can be managed by using additives that slow the formation of crystals and by blending feedstock or fuels.

Biodiesel blends are B2, B5, B10 and B20 with the numbers indicating the percentage of biodiesel. B2 or B5 may have no effect on cold-flow properties of the biodiesel blend. B20 could freeze about 3 to 5 degrees F faster than No. 2 petroleum diesel.

Using biodiesel in cold weather involves the use of best management practices.

Research of the cold weather properties of biodiesel is heavy and ongoing. Successful additives and blends prevent fuel gel, however, biodiesel is normally blended with petroleum-based diesel at variable percentages to improve cold-flow properties. Cold-weather additives may be used with biodiesel in the winter and fuel should always meet ASTM D6751 specifications.

PermaFlow, an Indiana-based biodiesel research organization, developed a process where B100's cloud point was tested at -45 degrees F when tested in Alaska's late winter.

No.2 diesel fuel has a cloud point in the range of -10 to 20°F and will begin to gel and plug filters. No.1 diesel fuel has a cloud point -40°F or less. Cold flow additives along with fuel heating elements are used to alter those cloud points. Blending biodiesel over 5% results in higher cloud points and additives or No. 1 diesel is often used .

Neither ASTM D975 nor D7467 have a cloud point specification but both require that the customer be notified of cold weather tendencies. Good tank maintenance practices helps ensure cold weather operability.

Additional Resources

Minnesota Department of Agriculture – Report to the Legislature: Annual Report on Biodiesel

http://www.leg.state.mn.us/docs/2014/mandated/140323.pdf

Solving a Great Biodiesel Mystery

http://biodieselmagazine.com/articles/8691/solving-a-great-biodiesel-mystery

B100 goes to the Artic Circle

http://www.biodieselmagazine.com/article.jsp?article_id=3476&q=&category_id=14

Biodiesel in the Sky and at home

http://www.biodieselmagazine.com/article.jsp?article_id=3029&q=cold%20weather&category_id=6

Biodiesel Cold Weather Issues

www.state.mn.us/.../Biodiesel_Cold_Weather_Issues_022009043331_BiodieselColdWeather.pdf