My centrifuge rig

[powerstroke73L]

I don't know how many folks are using centrifuges to clean/dewater their oil, but I just got mine up and running finally this weekend. It cost a few bucks but I couldn't be happier with the results. For those of you who aren't familiar with them, centrifuges clean oil by forcing it under pressure (about 90 psi) through a rotor spinning at about 7000 rpm. The junk in the oil sticks to the sides of the rotor and the clean stuff comes out of the bottom. The system also dewaters through a combination of heat (the oil has to be heated to between 140/160 degrees in order to move through the centrifuge) and a venturi effect created by the oil being sprayed at high pressure through the nozzles inside the rotor. This is not a new idea, I just copied it from another guy on the infopop forums. You can read more about his setup here:

http://biodiesel.infopop.cc/eve/forums/a/tpc/f/159605551/m/2001011761

Here are some pictures:


This is the whole setup, which fits on a 5' x 2' platform made from scrap wood I had laying around in my garage. Pretty soon I'm going to add some heavy duty casters that I picked up from a junked stick welder so I can move it around easily. The drum was obtained from a local shop (used to contain motor oil), and the heating chamber was made from 1 1/4" black pipe with fittings to accommodate the inlets, outlets, and water heater elements. The oil enters at the bottom of the pipe and passes over the first element, then up the pipe, and over the second element before hitting the centrifuge. Both elements are 5500 watts each (on 208 volts) so on household voltage (115) they're putting out around 1375 watts each.



Pictured here is the top of the heater and the centrifuge itself. I used pressure washer hose rated to 300 psi @ 70 degrees F. So far its holding up well, but I might get a new hose rated for a higher temperature even though I'm working at less than half the rated pressure. The oil travels into the centrifuge through the fitting with the pressure gauge on it (included with the centrifuge) but there is a ball valve plumbed inline. When starting the motor the ball valve is left open and the oil simply recirculates into the drum. Once the system is up to operating temperature you slowly close the valve until the pressure gauge reads 90 psi. The centrifuge will spin up and clean oil will begin to flow out of the bottom. The capacity of the centrifuge is about .9 GPM @ 90 psi. My pump puts about just a hair more (about 1.1 GPM @ 90 psi), so I still have a fair amount of oil bypassing, but that just means it will take a little longer to filter it all. The junk that is spun out of the oil sticks to the side of the rotor and the centrifuge is cleaned by taking the rotor out and scraping the gunk off the sides. The water flashes off as vapor through the combination of heat and the quick transition from high pressure to low pressure when exiting the nozzle inside the rotor.



This is the pump/motor itself. The pump, fittings, tubing, and coupling (Lovejoy flexible "spider" coupling) were all purchased new. The motor is a 1/2 HP 1725 RPM I had laying around. The pump is a gear type with 1/4" ports. It's a Dayton (Grainger's house brand), part number 6NY91. You can read more about it here:

http://www.grainger.com/Grainger/wwg/productIndex.shtml?from=Search&newSrch=yes&operator=keywordSearch&search_type=itemnum&action=Go%21&QueryString=6NY91&submit.x=10&submit.y=12

Closeup of the pump:



The pump is set up so that I have two 3/4" ball valves on the outlet. To run the CF, one is closed and one is open to allow oil to recirculate through the system. When the oil is finished processing, the valves are switched, and the pump can then be used to fill the truck. I plan on adding a 10 micron Goldenrod on the outlet just to filter out any junk (dust, bugs, etc...) that could get into the open topped barrel prior to filling the tank.

Again, this is not my original idea and SunWizard over on the infopop forums is the guru. Check his posts out as they are much more detailed than mine and any information you could possibly need will be there.

[greasyX]

Centrifuge(holy grail)

I as well use a centrifuge(oc50)f2f Setup,why didn't you use thread lock on your fittings?that white tape will contaiminate your oil real Quick,If you don't believe me pull your #8 injector it will look like cream cheeseI used red thread lock,you have more setup time,(for the thread lock to cure) but its cheap insurance for your injectors.Not trying to be a nay sayer, but just looking out for a fellow Vegistroker!!!...good luck......grease out

[powerstroke73L]

I as well use a centrifuge(oc50)f2f Setup,why didn't you use thread lock on your fittings?that white tape will contaiminate your oil real Quick,If you don't believe me pull your #8 injector it will look like cream cheeseI used red thread lock,you have more setup time,(for the thread lock to cure) but its cheap insurance for your injectors.Not trying to be a nay sayer, but just looking out for a fellow Vegistroker!!!...good luck......grease out

Hmmm...never thought of that. I know that in the V3 manual it stresses to NOT use teflon tape on fuel line fittings, but I just figured that this was due to the fact that the fittings on the head are post filter. I would think that between the CF, the Goldenrod, the Donaldson on the V3, and finally the stock filter, any stray pieces of tape would be caught. In any event, my system isn't installed yet and I've only processed about 50 gallons thus far.

[Elvia]

I have a SpinnerII 600 HD Centrifuge. 16 gpm. fueled be a 2 HP electric motor and a 16 gpm viking pump. to get the oil up to temp, I have 2 4500w water heater elements wired to 220 volt and another 4500w wired at 120 in the tote it pumps from. the oil is moving so fast past the elements it takes about 2 hours to get to 140-150 degrees. When it reaches temp, I turn off the 220 volt elements and continue with the 120 in the tote. i have 2 275 gallon totes plumbed together at the bottom valves. I then pump from one tote and discharge into the 2nd tote.
This spinner can hold 6 (SIX) liters of gunk. Thats alot!!! I run the system for 18 to 24 hours and get squeaky clean and dewatered oil. I have about 3200 miles on this filter so far.
Working on another project now... More on that later.

[greasyX]

teflon tape

the teflon tape can break down smaller then 1/10 micron,then it accumilates at injector nozzles(not much sticks to teflon except teflon),I believe it was the owner of GFS that learned the hard way on his Excursion(karma can be a MF)do onto others as you...well U know the rest.If I remember correctly thread lock was originally Developed by NASA for their fuel systems because of the teflon issue..good luck with the install....grease out.

[SC Grizz]

I just put together a centrifuge rig and sealed the pipes with a joint compound that has Teflon in it. Should I be worried?

[Clay]

I just put together a centrifuge rig and sealed the pipes with a joint compound that has Teflon in it. Should I be worried?

Not at all.

[Allofus123]

Here's a pic of mine. It was built by a guy that goes by the name of The Professor (Bob) over on Frybrid. The concept of a completely enclosed system was what we were after. The system looks a bit different now as I had to modify several things to get it to work properly. The two biggest problems were the CF not draining properly with 3/4 pipe and a lack of venting for the condensation build up inside the HWH. The drain issue was solved by opening some venting on either side of the drop under the CF. The condesation fix was opening a vent on my inlet side of the HWH and pumping air from an aquarium pump into the side inlet across the top of the oil. The hot air vents. Doesn't work so well on half batches as the air cools to quick before venting.

[powerstroke73L]

I think I found out the reason for the confusion here-this was taken from Wikipedia:

Because of its chemical inertness, PTFE cannot be cross-linked like an elastomer. Therefore it has no "memory," and is subject to creep (also known as "cold flow" and "compression set"). This can be both good and bad. A little bit of creep allows PTFE seals to conform to mating surfaces better than most other plastic seals. Too much creep, however, and the seal is compromised. Compounding fillers control unwanted creep and improve wear, friction, and other properties. Sometimes metal springs apply continuous force to PTFE seals to give good contact, while permitting some creep.

Teflon is like viton and other advanced polymers in that it reacts (and therefore dissolves) with almost nothing. Diesel fuel and WVO alike shouldn't have any effect on it, however, what it does do is creep, or cold flow. If teflon tape is applied in a plumbing system there is always the possibility that it will creep to the point that small pieces break off and enter the fluid flowing through the system. As I said, this is no problem for me as I have multiple filters for the oil to pass through before hitting my injectors. However, putting teflon tape downstream of a filter can definitely be a problem. If the guy referenced in greasyX's post did in fact have a problem it was because the teflon experienced some creep to the point that it entered the fuel system and got caught up in the injector.

[Clay]

the teflon tape can break down smaller then 1/10 micron,then it accumilates at injector nozzles

1/10 micron would be microscopic in size and visible only with a powerfull microscope....not saying it would be good for it but it would pass though.

[powerstroke73L]

1/10 micron would be microscopic in size and visible only with a powerfull microscope....not saying it would be good for it but it would pass though.

1/2 (0.5) a micron is equivalent to the size of a single particle of smoke. 1/10 of a micron would be 0.0000001. It's considered acceptable to filter oil to exclude particles greater than 5 micron, so 0.0000001 micron should be fine. However, since the teflon doesn't dissolve anyway I don't think it will be a problem so long is it's not used downstream from a filter in a fuel system, which in my case, it's not.

[Clay]

1/2 (0.5) a micron is equivalent to the size of a single particle of smoke. 1/10 of a micron would be 0.0000001. It's considered acceptable to filter oil to exclude particles greater than 5 micron, so 0.0000001 micron should be fine. However, since the teflon doesn't dissolve anyway I don't think it will be a problem so long is it's not used downstream from a filter in a fuel system, which in my case, it's not.

Exactly....

[Marv]

The only place I used teflon tape on mine was on my pre-filter barrel fittings (drain and supply to HWH) and the connections (fuel supply/return, coolant supply/return and vent) on the tank in the bed of the truck. Everything else is either teflon paste (for filtration setup) or Loctite as provided by DFA.

Also, there is no teflon tape present at any joint past the filter for both my filtration setup and the V3.

With the filter canister on my filtration setup and the Donaldson on the V3, I feel confident that teflon in the oil shouldn't be a problem.

[Clay]

FWIW, i have been slowely removing parts of my still and replacing the teflon tape with joint compound. The tape will eventually leak it seems. Also the black hose i have originally used has all been replaced with the clear hose that is reinforced with the string inside...whatever its called. The black heater line hose i used would actually sweat oil right through it...don't ask me how but after a year or two that hose was covered with oil and you could see where it looked like sweat beads all over it. When i replaced it, it was rather limp feeling as if it had broken down physically.

[Elvia]

I'll have a look at mine. Although all my piping is 1 1/2 and 1 1/4 black iron pipe. My discharge is 3" pvc piping. I will take some pics this weekend and post. Its is quite different from everything else out there.