WVO Filter Design - My Filtering Setup

The internet is full of designs for WVO filtration. My design is similar to many of these but it includes a few simple tweaks which I believe make life easier.

The Barrel / Settling Tank

Starting with the barrel itself, where the WVO is allowed to settle. A lid is important as you want to keep dust, insects and whatever else out of you oil, but it doesn't really have to be perfectly airtight. Upon upon a time I felt the need to vacuum seal my barrels, but experience has taught me this is unnecessary, so ignore the tap fitting you see on the lid in my photos. I don't make use of that any more.

My barrel was purchased from eBay. The last time I looked the guy selling these barrels had stopped tradining. Pity. They were actually recycled shipping containers, so that adds to the green value of what we're doing. However there are plenty of similar barels out there. Shop around!

Release Tap

My release tap is positioned approximated three-quarters of the way down the barrel. This allows all the impurities to settle below the level of the tap. However, I decided to incorporate a float feed mechanism.

The float feed ensures that the oil is not taken from the top of the tank but instead from approximately 1 inch below the surface. A small section of pipe was consequently soldered on to the tap to enable a hose to be attached between the float feed and the tap. Thus all the oil that comes out from the tap is neither from the surface or from the bottom of the tank.

Float Feed

I took a copper "T" fitting and drilled an 8mm hole in the top. Through this I inserted an M8 bolt and secured this in place with a nut. I then added a small length of 15mm copper piping to the T and soldered everything together, including the bolt.

The M8 bolt was the perfect size for a standard ball float (which I bought at Wickes for approx £1), so this simply screwed on the the bolt's thread giving it a secure fixing.

I connected a length of garden hose to the end of the float feed with a hose clip and connected the other end of the hose to the tap. This means that oil is removed from the settling tank from approximately 1 inch below the surface level which is, theoretically at least, where the cleanest oil resides. As the level of the oil drops, the float remains in an upright position and feeds the tap until the level of oil falls to the same level as the tap (approx three-quarters down the barrel). As the oil below the tap is likely to contain fats and impurities, this is ideal.

Sludge Drain

As mentioned before, the heavy impurities and water sink to the bottom of the barrel and stay there, so it's nice to be able to remove these. With that in mind I decided to add a drain facility.

I made this using 22mm copper fittings. A tank connector was drilled into the bottom of the barrel and to this was connected to a 22mm pipe. At the end of this I placed a full bore release valve (remembering to make sure it was in the closed position). For added support I glued a block of wood and a pipe clip.

Lid

As stated earlier, I used to be fixated about the idea of vacuum sealing my barrels, but experience has taught me not to worry about such obsessations. However a good lid will keep out flies and dust and all manner of rubbish, so if your barrel comes with a lid, great. If not, I'd suggest making one. Open-top barrels invite disaster.