(edit- This thread got really long so I posted a summary of my posts to this thread here.
I just ran my first batch of 15 gallons of WVO straight from the restaurant barrel, 100 mesh (149 micron) screen on sucker, through the centrifuge with no other filtering and it works great. Easy to clean, no more filters to buy. Runs at 90psi, 1 gpm. I was surprised since Dana had me scared it wouldn't work from this thread.
Here is my rig, it goes pump>heater>centrifuge>barrel:
The pump is a free power steering pump off a 84 Mitsubishi montero, hooked to an old 1725rpm 3/4 hp motor I had. As small as 1/4 hp should work, this is what I had laying around:
This pump was easy since it had a rubber line going to the reservoir which I just turned upward and attached my inlet hose:
This goes into a 4500w 220v water heater element run at 110v (=1125w) in a tee in the bottom of the 1.25" vertical pipe. The oil started at 50 F and got up to 110 F first pass. I did 3 passes with decreasing amounts filtered each pass, lots in the first pass, with almost no black sludge 3rd pass.
Here is the black gunk that stays in the rotor (edit-better pic):
You guys working on the "holy grail" of mobile flash evaporator and filtering might want to look into this since with a little higher temp it might do both. Or you could do a flash or vacuum evap. then right into this. At 120 F I was seeing small puffs of steam or atomized oil when pumping the hot oil through 2 small orifices at 90psi. This oil was water-free to begin with according to a pan test.
The oil I started with was black and you couldn't see through it at all. And here is the sweet iced tea drinkable looking WVO after only 15 mins for 15 gals:
edit- This is a BLOG of my greasy science project. See further improvements to this rig on later pages, or in the summary link at the top of this page. Many batches of tests have shown a mistwash (which gets mentioned on many pages here) isn't helping and makes dewatering take far longer.
edit - new info:
With any version of this you should make provisions to capture the output of the centrifuge right when you turn it off. The output at that time is often very dirty besides containing up to 4 oz. of water (if there was enough to make free water.)
edit - new info:
Now I have a Sandy Brae water in oil tester, and here are the results from a centrifuge run I did recently. Average quality WVO source, FFA=2.5%, settled for 4 months. Began at 700 PPM and end 270 PPM measured with sandy brae, also measured every 30 minutes with my capacitive water in oil meter (link: Homebrew capacitive water in oil meter testing) to make this chart, and temp. compensated.
This message has been edited. Last edited by: SunWizard,
The only problems I had was the little rubber gasket on the hot water heater element 1" MPT couldn't hold the 90 psi, bulged out and sprung a small leak. Anyone have experience sealing those under pressure? The threads don't seal on their own like normal pipe thread. I am guessing an O-ring may work?
One drawback is that it was loud, probably because the metal barrel acts like a resonator. It winds up to 6000rpms very quickly, sounds sort of like a vacuum cleaner.
sounds like winner thus far...
hopefully you can do some more testing and get back with us.
things like if it will remove water or not... and what happens if you run the oil thru a 1 micron absolute filter.
neat drive set up btw..
Though your argument is very clever, I don't think it will lead to the results you desire. gandhi
Is this the same type of centrifuge used on semis? I hear thay are very expensive. Would it be cool just to dump wvo into a dirty tank and have it go though a centrifuge while on the road? then transfer the clean oil to the clean tank to run your truck on That seems like a better way to go while on long distance driving.
What did it cost And where did you buy it..?
Oh which model did you buy.
Thanks for the report
Yes this is made for semis. It cost me $230 including shipping on ebay here: http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewIte...ame=STRK%3AMEWA%3AIT
You can probably email the guy and get one, the seller is the maker of them.
In the long run I think the price is worth it since you never need to buy replacement filters.
And it reportedly filters to 0.5 micron which is kind of hard to do with filters.
And yes this would work great while on the road, that is one reason I am trying it out. And you got it, you have a dirty tank and it pumps into the clean tank. In my example I showed just one tank but it can pump from one to another just as easy. I pumped from 5 gallon glass carboys into the 55 gallon drum that the centrifuge is mounted on. You could easily mount it anyway you like.
You either need a recess for the quad ring to sit in, like it does on a water heater, or you need to improvise a collar around it to keep it in.
I believe the rating on those when in a water heater is something like 160 psi test. My water pressure is 80 psi.
please tell us more! where does the crap go? the oil i get is sort creamy colored. after sitting a couple of weeks the thick stuff goes to the bottom, clear(er) to the top. with the centrifuge there has to be two streams coming out- the good stuff and the bad stuff. it's about 2/3 to 3/4 good stuff.
how much was it? where did you get it?
The crap all gets stuck inside the rotor of the centrifuge, (which is the 2 parts with the black gunk on it you see in my hand, it had a lot more before I ran and got the camera) which is real easy to open up and simply wipe out with a rag.
It doesn't separate into two streams, it only moves solids to the outside where they can be cleaned off. As SunWizard said "This oil was water-free to begin with according to a pan test" so further testing would be needed to see what would happen with oil like yours. Would be interesting to try. Maybe, if he's willing, you could ship him a cubee to test?
I plan on adding some water to some oil and trying some nasty oil to see what happens. Dana reported that a similar unit would emulsify if there was too much water. Your milkyness is probably partially hydrogenated (PH) which if dewatered will work with this since it gets heated before centrifuged. I think the oil I used was PH and milky too but was so black it was hard to tell.
Here is the makers website with a diagram of how it works: http://www.dieselcraft.com/productinfo_OC_1.html
This looks very promising. I will try this out in series with a Tim Cook Flash Evaporator, to build the "holy grail" of on-board filtering and dewatering.
1. How easy is it to clean. When you remove the rotor to clean it, can you do so without all the mess on the floor.
2. How much WVO can you clean before you have to clean the rotor. I know somebody will say "It depends", just need your observation on how much gunk was removed in your 15 gallons. Could the rotor have taken more gunk? If so, can you extrapolate loosely how much WVO it would have taken to fill up the rotor with Gunk?
3. Will it work if the flow rate was less than .93 gpm. Since this will be before the FE, the flow rate for mine will only be 5 gph.
1. very easy to clean, you open it, take a nut off the rotor, and wipe inside parts with a rag. It makes a mess on the rag but not much else.
2. I think you could clean lots before the rotor fills. The dirt is really compressed. I could have done hundreds of gallons of the oil I had without cleaning it. But I wanted to clean it often just to see the goop
3. It needs specific flow rates to work. I think the dieselcraft website gives info, but it ranges from .6 to .9 gpm. You would probably want this after most water has been removed. But you may be able to make this do at least part of the dewater too, since it functions similar to the flash evaporator but at a higher flow.
Sealing the heating element -- I make new gaskets from 1/16 inch thick teflon sheet gasket material, then use a pipe tap and cut the threads in the "T" or coupling so that I can screw the heater in hand-tight and still have 1 to 1.5 threads to go between the fitting and the gasket. Remove the heater and goop both the internal and external threads with silicone putty, being sure to work it completely down into the bottom of both threads. Screw the element in so the new teflon gasket has a bit of pressure on it but not enough to cause it to bulge. Helps to smooth off the end of the fitting with a grinder to create a more flat surface for the gasket. This has worked on several heaters, up to 150 pounds on the flash evaporator.
You mention "2 small orifices", where are these, are they the orifices used to spin the rotor ?
Pump pressure -- You mention "90 pounds", do you have some sort of pressure adjust or is the 90 pounds just what ended up being created from this pump/orifice combination ?
Mate that is really impressive. If tests on the final product stack up I reckon you have cracked the holey grail of oil polishing.
I am still a bit suspicious that the fine stuff, up to 5 microns could still be present in part. The finished product should be crystal clear when hot. Can you put the oil through a couple more times with a clean rotor and verify that there is on fine deposit. Even if there is it may mean a few more passes are required. With the quoted flow rate this would still be ok.
Thanks for the post, very good work.
1977 Mercedes 300D 2 Tank HOH, Heat exchanger and Vegetherm.
Thanks for the sealing tips I will try it. Yes the 2 small orifices are what spins the rotor. I got 90psi by design plus some luck that my junk car's power steering pump was the right size. I will make a new post here about design and operating this rig.
I think it would be very easy and the greatest to combine your flash evaporator with this thing, since the heat and orifice part is so similar.
And Tim the orifices (orifii?) on this look to be standard brass pipe thread which I bet you have a pile you could play with in there for different flows.
Design and operating this rig:
For the pump, you want a small gear (edit-or vane) pump. I almost bought this Oberdorfer 1000BR gear pump for $80 until I realized that power steering pumps are the right size pumps. Most pumps are too big, you want a small one, this one is about 3"x3"x3" not counting the pulley and reservoir. You also want it to be easy to mount and to seperate the reservoir to input directly to pump. Other models with the same pump I used is Dodge D50 and mitsubishi 2.5L truck from 80-89 and Monteros from 84-89. Test your pump with open flow, it should be about 1.5 gpm. This is the right open flow which will magically drop to about 0.9 gpm at 90psi. If its not the right flow, change the pulley size on the motor. My motor pulley is small so its reducing the slow 1725rpm motor some. Or you could use a variable speed motor if you wanted to be really cool.
Turn on the pump to fill the lines before turning on the heater! I turn it on for just a few seconds, it self primes quick, until the first oil drips from the centrifuge, then shut off. You don't want cold oil going through. Then I turn on the heater element, wait about 1 minute, then start the pump. When you hear it whine you know its working.
Future ideas to test:
This is so close to a flash evaporator already, that I designed it to have a second 4500w heater element at the top T.
Idea #1. put a 3 way valve on just before the centrifuge, run it through a seperate orifice several times into the same barrel until its hot and flash evaporated. Then flip the valve to filter.
Idea #2. About a pint of water may be trapped in the rotor along with the gunk. Try putting a quart jar under the output just when I shut the centrifuge off to see if any water comes out. (edit- see page 12, this idea works,catches about 4 oz., it may be possible to remove sugars/acids without a mistwash if you capture the output at pump shutoff)
Idea #3. Run this thing hot enough to do the flash evap and centrifuge in one pass.
I had 2 heater elements in it at first, when the top one sprung a leak and sprayed a fine column about 30' straight up producing a warm golden shrimp smelling oil shower I took it off until I solve the gasket issue.This message has been edited. Last edited by: SunWizard,
Since you were able to draw through a 100 micron screen you obviously had pretty good oil to begin with, despite the color. Would be interesting to see how well it works with really gunked up stuff.
You need to collect and condense the vapor you were seeing. I get vapor at times when pumping clean oil through a restriction but it is just atomized lighter oils.
I bet this would be great for polishing settled oil, based on your results. It could just draw from the bottom of the barrel, and return to the top. Let it run several hours, then switch the output through a filter to the final barrel. Should extend filter life considerably, or even indefinitly.
Glad you went ahead and tried this despite the discouragement you received before!
You sure got a deal though. List on these things is over $400. I imagine with demand increased, they won't be as likely to discount them.
I hope however that before you get too encouaged by the early result in your testing and proclaim it a success that you proceed with testing of the units ability to remove suspended water. You should also be aware of the need to wash wvo before any evaporative dewatering. I have posted enough on this subject that I don't think I need to repost why this is neccesary. But if I do..just ask.
Edit: If you are just using the unit as a filter it seems to be a very expensive one.
Most filters for VO cost under $50 and filter just as adequately as the DieselCraft Centrifugal filter setup you describe. n fact I beleive I can convert a vehicle and fabricate a WVO collector, prefilter, and dewatering unit for what your Dieselcraft Centrifugal filter processor costs.
It has a Gee Whiz" appeal with all the mechanisms spinning and whirring and vapor drifting...but as a practical matter it isn't anything more than an increadibly expensive WVO prefilter.This message has been edited. Last edited by: danalinscott,
I am very happy with the unit just as a filter, its much easier than the other options I have seen. Thats why I tested that aspect first. The centrifuge doesn't need to do the dewater for me to consider it a sucess, I can do a vacuum or flash evap before this if needed. But doing it all with one is the holy grail! The water removing is the next test.
And yes I know about washing I have been reading your posts about it here for a while. Already have my misting head setup for this same open top barrel.