Stir Washing Biodiesel



Search this site!

Stir washing biodiesel is a very fast method of washing, however it only works well with fully reacted fuel with minimal soap content... otherwise it will cause emulsions in a heartbeat!

Many home-brewers have used stir washing with great success and much time saved. They attribute their success to working with high quality fuel. They recommend shake testing a small sample (to see if it causes an emulsion) before stir washing an entire batch.


How it Works:

Stir washing biodiesel works the same as other water washing methods in the sense that the water collects the contaminants out of the biodiesel, which then drops down to the water layer which is removed. The difference in the stir method is that the causes of emulsions are addressed and fixed, thus allowing for aggressive aggravation of the mixture to work!


Supplies Needed:

• Wash tank

• Outlet to drain wash water

• Electric drill

• Paint stirrer attachment

• supplies needed for the wash tests of you choice


How to Stir Wash:

*A ‘shake test’ is recommended to check for possibility of emulsions BEFORE stir washing the whole batch!

*Many brewers who use this method recommend a pre-wash.

This will reduce the soaps and stop the reaction, lessening the chance of emulsion.

Figure out how much water to add. Add 1/3 water to 2/3 of the volume of oil that was used to make the fuel.

Add the water – 120°F is best (you don’t have to be gentle when adding it as in the bubble and mist washing methods).

Use something such as a paint-stirrer attached to an electric drill and mix the biodiesel with the water for 5-10 minutes or until the mixture is a consistent consistency (haha).

Let the mixture settle for an hour or longer.

Drain the wash water off the bottom, add fresh water and wash another 2 times or so until it passes the wash tests.

After the last wash, let the mixture settle for 12-24 hours and then drain the water.


Return form 'Stir Washing Biodiesel' to 'All Methods of Washing'

Biodiesel Homepage