WVO Prep Tank




Here's a little attempt at an all-in-one, "economy" style WVO (waste vegetable oil) prep tank, meant to get that grease all ready and good to go! In theory, the tank should filter most any particulate matter from the waste oil, as well as separate any water suspended within the oil (via heating the oil and then letting it settle again). It even has a nifty gauge to check oil quality and quantity :) 

The main purpose here was to construct a practical, fairly inexpensive, yet effective means to store and prepare the WVO. Hopefully that was accomplished...


Step 1: Gathering the Parts...

First step is to gather the parts. I used...

- Plastic 55 gallon drum (10.00)
- Electric hot water heating element and adapter kit (26.00)
- Misc. plumbing adapters (20.00)
- Filter bag (10.00)
- Electrical project box/components (10.00)

Step 2: Preparing the Barrel...

Now on to the good stuff.

I started by cutting a 6 1/2 in. whole in the top of the barrel... This is where the filter bag will fit, as well as allow for a way to clean the inside and reach your hands down there to tighten up the plumbing. One more hole on the bottom for the center drain, and two more on the side (not in picture) for the gauge installment. 

When attaching the plumbing, I made sure to use rubber grommets/washers wherever possible, and gasket seal where applicable. The sizes/adapters can be whatever you like, but I used mostly 3/4" fittings.   

For the heater installment, it's just a hole with the adapter bolted on, and the project box glued straight to the barrel with adhesive caulk. (The metal plate above the box is a mistake... I decided to lower the heating element). 

Step 3: Final Steps...

For now, i just have a coarse strainer that the oil is hand-poured into (or slow fed by a 5 gallon bucket hanging from a hook in the ceiling), which then feeds into the 1 micron filter bag. If your oil is fairly clean to begin with, then the filtering process doesn't take too long, even at room temperature. I just took a piece of vinyl tubing and cut it down the middle lengthwise, and glue it around the edges of the hole to protect the bag from any sharp edges. 

In the back of the barrel is the completed project box with the wiring from the heating element, which is so far just wired into a circuit with a simple switch and a 16 gauge cord. I haven't tried the heating element in the oil yet... and I might need to install some type of thermostat or regulator if it gets too hot (but we'll cross that bridge when we get there). 

Also, I'd like to eventually add a rotary hand pump to the top of the barrel (via one of the two bung holes), which will pull oil from about 1/4 of the way up from the bottom. Until then, I can just use the relief valve to get clean oil out. 

And... so far, so good! I make sure to update with any changes/improvements I make. And I'd love to hear any comments if you have them. Good luck!



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    12 Discussions


    6 years ago on Introduction

    Great idea, and very inexpensive. Yes the thermostat will adjust with the screw, but what I have done is to use a 220 volt heater on 120 volts, and it doesn't overheat. I have about 500 gallons of WVO on hand at any given time, but don't filter or dehydrate it till I'm ready to use it. I mix WVO 4:1 with kerosene and use it directly in my pickup truck and diesel generator. I have put almost 100,000 miles on my truck and 2000 hours on the generator without incident and at less than 1/5 the cost of Diesel fuel. No modification are necessary, you can't tell the difference, except in the wallet! Cheers, John

    1 reply

    This is such a great idea! I've just finished mine and it's working great, thanks for the inspiration!


    Reply 8 years ago on Introduction

    yup, or if you convert the vehicle with any number of fuel heaters, use it straight as it is (after you heat test for lack of water, and its filtered). We've moved on to using home grown algae oil with a closed loop benzene extraction, before using the oil in the vw.


    Reply 8 years ago on Introduction

    I'd be interested if you could explain your process for extracting and refining the algae oil. I've seen a bunch of people talking about possible ways of making it useful, but no one has actually done it.


    8 years ago on Introduction

    I know WVO means Waste Vegetable Oil, but you might want to add that to the title of the i'ble. I like it!

    1 reply

    8 years ago on Introduction

    Excellent job!!!! I would just suggest that you absolutely add a thermostat to the heater (as well as a water heater blanket around the drum)- from a messy personal experience! The plastic sides soften before the oil will burn or boil. The softer sides eventually rupture when you're not looking at 2 in the morning;) !!!! As a more permanent fix, I would encourage you to get (a single one at first) stainless steel keg and make the same adjustments. There is no risk of rust (if you use stainless adapters) and nearly as thermally insulative as the plastic! Later on, if you want to add volume, you can cut the top off one keg and the bottom of one keg and have them welded together! 3 kegs make 45 gallons!

    1 reply

    Reply 8 years ago on Introduction

    heck ya! having a stainless steel set-up would primo. unfortunately, i don't really have the welding tools for that at the moment, but someday i would love to take your advice. as far as the thermostat goes, do you think i'd be able to just add simply (only) an electric hot water heater thermostat to the circuit, and adjust the temperature via the little dial on the thermostat? either way, thanks for the comment!