Treating Emulsification with Salt

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There are many methods of treating emulsification, with salt being the fastest. It has been successful in breaking some of the most stubborn of emulsions.

Why this works:

While the heat decreases the density of the oil, the salt increases the density of the water. This allows the two separate from each other easily.

How to Do it:

Pre-dissolving the salt in hot water will disperse it better than just sprinkling, although plenty have had success sprinkling salt over the surface of an emulsion.

Try adding 1 inch of salt per 50 gallons of emulsion to a 5-gallon bucket, add hot water and dissolve. Gently add the salt mixture to the emulsified batch, then gently stir it in and let it set. If it doesn’t break, do it again.

The Flaws:

Some have reported that using salt to break emulsions caused a need for more washes.

It is harder to tell visually when the biodiesel is clean because the salt causes the wash water to be clearer than usual.

Washing does not seem to remove as much soap as normal with the salt present.

There is no way to prove all the salt has been removed aside from ASTM testing

(very expensive). Salt in the fuel can cause corrosion of metals.

If you are concerned about some salt residing in the biodiesel, try to treat the emulsion using heat and settling.

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