Re: mixture question

I don't see any reason why it would. As far as I know the B20 blend at
Carson Oil has always been ULSD and I've heard of no problems.

If wax forms at low temps, then I don't see what sulfur would have to
do with it. Does anyone know if sulfur contributes to cold flow
properties of diesel.

Currently under great discussion in the industry is problematic water
content in biodiesel after it has left the factory.

Biodiesel is actually hydrophobic (repels water) at a stable
temperature. Although changing daily temperatures cause thermal
expansion and contraction of the fuel. When the fuel contracts it
becomes hygroscopic and absorbs very small amounts of water from the
atmosphere (up to about 1200 ppm).

Normally this isn't much of a problem because of the high turnover
rate at most stations. The fuel just doesn't sit around long enough to
cause any problems.

But as the temperature drops, the water in the fuel will form ice
crystals near 32F. These crystals provide sites for nucleation and
accelerate the gelling of the fuel. It's my understanding that the
long chain fatty acids are the first to bond and will effectively fall
out of solution or end up clogging filters.

I've heard that some producers are trying to encourage retailers to
install decanting breathers on there storage tanks and transport
trucks to prevent atmospheric humidity from contributing to this
effect.

Fuel can supposedly be fixed by heating to high temperatures to break
the water <-> fatty acid bond. Then the water can be removed through
conventional absorbtion filters. Otherwise a real pain in the ass if
you had thousands of gallons.

This is my current understanding, if anyone else has a better or more
complete understanding of this. Please share your experience.

--
Jeff Brandt
Sun Break Biofuels, LLC
mailto:[email protected]

On 11/28/06, Brian Jamison <[email protected]> wrote:
> Anyone hear of issues mixing the new ULSD with B99?  I haven't been able
> to confirm a report that wax may result in cold temperatures.
>
> -B
> --
> Brian Jamison
> President, Board of Directors
> GoBiodiesel Cooperative
>
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