A new report sponsored by the National Biodiesel Board (NBB) offers guidance on the proper blending of biodiesel fuel to achieve consistent performance in cold weather.
The NBB established a Biodiesel Cold Flow Consortium to study the blending properties of biodiesel in response to the need for more data on the part of petroleum blenders and distributors on the most cost-effective means to achieve a homogeneous biodiesel blend in cold weather.
The Cold Flow Consortium designed its study and report, Biodiesel Cold Weather Blending Study, to determine accurately the temperature where biodiesel and No. 1 and No. 2 diesel could be blended at 2 volume percent (2%) biodiesel, while meeting standards for blend precision and homogeneity.
The study focused on preparing 2% biodiesel (B2) blends exclusively.
The study team goal designed a small blending test rig to simulate splash and proportional blending at the terminal. Unadditized No. 1 and No. 2 diesel fuels were selected, along with three biodiesels with a range of cold flow properties.
The study concluded, based on its testing, that successful B2 blends were made when the biodiesel was 10°F above its cloud point. Because of the variety of fuel properties, the target temperatures for blending will need to be determined on an individual basis based on the fuels and actual winter temperatures at the terminal. It will be important for blenders to request cloud point information from suppliers for cold weather considerations.