Well my hands have blisters from spending 2 ½ hours on the end of a barrel pump to pump 170L of used tallow from a fish and chip shop, I hands still hurt and are numb two days later. Better solution needed.

Many people use a vacuum collection system, they seem like a great idea but, some of the shops I plan on collecting from do not have rear access there for I need to bucket the oil to take it out the front, and I cannot seem to find large pressure vessels.

So I plan on making a system to pressurize the WVO drums to extract the oil, with a spear sealed in the 2” bung and air pressure applied through the smaller bung, I have a few questions about them however.

Vacuum system folk say that 10” of vacuum will move oil up to a very thick consistency, but that most people run there systems at about 20” of vacuum and move the oil really quickly.

Question 1

5psi of pressure has about the same force as 10” of vacuum and 10psi has about the same force as 20”of vacuum, so do you think that a system that applies 5psi to a barrel of extremely thick tallow will move it at an adequate speed to empty in say under 15 minutes.

Question 2

10 psi of pressure would make thing move a little faster as it has the same force as the 20” vacuum systems commonly used, but can a 44 gallon steel drum take this much pressure (I don’t want to find out the hard and embarrassing way).

I would appreciate any input from people who are currently using this type of collection system. Further if any Aussies have any advise on where to locate a large vacuum capable vessel it would be appreciated.

Regards,

Martin

My experience with using air in a barrel to move its contents is limited to hydraulic oil, but I can tell you the barrel started to expand, badly at around 8 PSI. Now I was restricting the outlet with a valve and had a pressure regulator on the barrel. It is a great way to move a liquid. First I had a 1” hose outlet and just the ¼” air line inlet, no regulator worked great other than stopping the oil when needed (I need to stand by the nozzle or delivery end of the 1” hose not the barrel). So then I put a valve on the end of the hose and a low pressure regulator at the inlet set it on about 3 or 4 PSI and every thing was perfect. Well then the office didn’t want us to charge out a whole barrel of oil at a time and I had to put a meter on it, that would measure in quarts, this really slowed the flow down and I started to increase the pressure when I got somewhere around 8 PSI the barrel top started to push up and make a dome top. What I don’t know is how much restriction the solid or semisolid oil will cause, I would think that it would be pretty great.

HHMMMM -- I never considered a "push it out with pressure" aproach. It would work better with a barrel if you used both suction on the collection tank and a few pounds pressure on the barrel.

I have been considering using salvaged 100 pound propane tanks as collection tanks, they hold a bit more than 25 gallons but are about half the diameter of a 55 gallon drum so line up nicer along an alleyway or fence. These are rated to handle up to 350 pounds pressure, I suspect that even 100 pounds pressure would push out pretty solid oil, especially if also pulling a vac on the collection tank. I would cut the original 3/4 inch valve fitting out of the top of the tank and weld in a 2 inch pipe fitting (do this with caution, flush tank with water and fill tank ABSOLUTELY full of water before doing any work on a propane tank), also install a shrader type air pressure valve (like a car tire uses). This would allow me to screw in one of my big collection funnels for collection and then remove the funnel and screw in a tube on the end of my vac collection hose, the tube would run to almost the bottom of the tank for collection. Put 125 pounds air pressure in the tank along with pulling 10 pounds vacuum on the collection hose.

It sure would be easier to only have to carry a small air compressor in the truck rather than the steam cleaner I had been considering to be able to melt the oil in the collection barrels. A LOT cleaner and probably a lot faster also. the steam cleaner approach calculated to need about 100,000 BTU's of heat to melt 50 gallons of solid oil and take at least 30 minutes. I will make up one of these tanks and give it a try. Thanks for the Idea, nicest approach I have seen to winter collection if it will actually work..

I would also point out that you can carry more "pressure power" than you can "vacuum power" if you are charging your tank at home and don't have a portable system to produce vac or pressure.

Also, for safety reasons, NEVER pressurize a 55 gal drum inside or with people around. They are not designed to withstand pressure and can fail catastrophically at relatively low pressures.

Propane tanks are good, well pressure tanks are good (often free at the plumber or well drillers who service them, just tear out the failed plastic bladder--you don't need it anyway), water heaters are good.

I think the big trick will be to make a "door" that's easy for the staff to dump the oil in, yet can be sealed easily and completely for pressure.

Good luck and let us know how you make out.

troy

I agree with the well-water tanks, I am watching for one of these that is the right size for this use. I fab up big steel collection funnels with non-sealing but rain resistant lids (shown here), they screw directly into the large bung on barrels. The Idea is to weld a 2 inch pipe coupler into the top of a pressure capable collection tank, screw the funnel in for collection, unscrew the funnel and screw in a sealed dip tube that runs almost to the bottom of the tank, this tube assembly will seal the tank and allow me to connect my vac collection tank hose directly to it for the grease transfer.

Using a standard 100 pound propane tank with my funnel on top makes the top of the funnel pretty far above the ground, this will be a problem for shorter kitchen help, already have some complaints about this even when using 55 gallon barrels and these funnels, a larger diameter well tank can be cut down to a more resonable height and still hold a reasonable quantity of oil (have to cut it anyway to remove the bladder completely), It will take a bit more work to make up these tanks but if the pressure approach works it will make emptying the tank a VERY clean and probably fast process, definatly a fast process in warm weather.

A standard 100 pound propane tank is about 14 inches in diameter and has a round bottom, a 14 inch diameter contains about 150 square inches, 100 pounds/square inch of air pressure will amount to about 15,000 pounds of "push" on the entire 14 inch diameter grease column, the round bottom should direct a large amount of this pressure to the center of the bottom (vector losses). If I use a 1.5 inch I.D. dip tube running down to within about 1 inch above the center of the bottom this pressure should easily push out even almost solid grease ( think toothpaste tube).

If this concept works well I could use 50 or 100 gallon, or even 250 gallon, salvaged standard horizontal propane tanks for collection tanks, fab a different type funnel on the top with a 2 inch ball valve just above the tank, close the valve, pressurize the tank and connect the vac collection tank hose to the 1 1/2 inch drain fitting in the bottom of the tank, WOOSH..

Great ideas here, thanks.
I am beginning to feel it is time to graduate from cubbee collection to drum class collection. So this morning I got online to glean what could about vacuum vessels and pressure pumps. It seems to me that the type of drum used also depends on the space at the restaurant and type of vehicle for moving oil. I'm now running Isuzu Troopers. I love them, my latest vehicle has a trailer hitch, although I don't think the little four banger diesel will pull much weight. I was imagining a 55 gallon drum, one of the heavy duty ones the methanol comes in, mounted on its own tiny trailer. Really the thought of oil collection is kind of gross, yeah I know I'm spoiled with cubbees. I only have to deal with the crap in the last part of the process.

This holiday weekend I did just this, I dealt with the fifty cubbees stacked around our otherwise beautiful yard here in the mountains of northern New Mexico. I built a bonfire on the side of the hill to the north of our house, using brush and firewood too awkward to fit in the wood stove. When it was super hot I began pouring out the gelatin sludge stuck in the bottom of the cubbees on the fire. Ohh nasty, but if I kept the fire hot by adding pine branches I had a smoke free fire. It took most of the day to dispose of thirty cubbees. I consolidated the rest so I don't have so many of them in the yard. Our fire department is always on alert for smoke, being as this area is mostly pine forests. I should have called them before I burned, but I guess the way I disposed of the plastic and muck worked well enough because the fire engines never came racing up the driveway. I just went out in the yard now that the morning is brightening, the pile was smoldering, I put a few more sticks on it, a splash of glycerol and lit it, smoke is gone.
Brian Rodgers