Questions about wmo.

[Booyah45828]

I've got some general questions for you guys running wmo about filtering wmo.

First off, I'm not really interested in using it as a fuel source for a road vehicle.

What I do have, is a waste oil furnace in the shop. Multiple times a year the fuel nozzle plugs up and we have to remove the burner assembly to clean the nozzle and preheater block. It's a dirty procedure and a pain in the a**. And being cold for a day or two isn't real enjoyable. So I'm looking to 'fuge the oil we burn, because I feel burning a cleaner fuel would result in me having to clean the burner less.

The furnace burns about a gallon an hour while running. It's fed by it's own 215 "primary" gallon tank, and we have a separate "secondary" 1500 gallon tank that all the raw wmo is put in to settle before being pumped to the primary tank. The old furnace was 200k btu, with a 100 micron screen. The new one is 300k btu, with a 144 micron screen and a 25 micron filter. I feel the new setup is better then the old one, but I read that the carbon/ash in the wmo is less then 1 micron, and it's that stuff that is/was plugging up the old burner.

So, here's my plan. I'm thinking about running a centrifuge on the pump between the two tanks. That way the primary tank would be clean oil, and the secondary tank would be the dirty oil. Since we bought the new furnace, we still have the pumping/filtering setup from the old one yet. So I'm thinking of running the old 100 micron screen/filter assembly, then the old pump, and then through the centrifuge and then the clean oil then into the primary tank. If I can find a heater, I think that would be a wise addition too before the centrifuge. I'm also thinking of running this whole setup through a spa timer of some sort. That way I don't have to worry about forgetting to turn it off and overfilling the primary tank.

Would a one pass system work? and would it be clean enough? How many gallon/hr do you typically run? How do you guys know when your centrifuge is full? How long/gallons do you run until you clean it?

I understand some of that depends on initial quality of the oil, but I'd like to think ours is good. It has minimal water, it's screened going into the oil caddy, and into the secondary tank. If I run a fuge at lets say 2 gallons/hr with one pass, would that be better then 10 gallon/hr in a recirculation mode?

I'd also like to do this on the cheap. I had my eye on the ultimate force and heater from pabiodiesel, but the price tag and year plus lead time turned me off. Are there cheaper options available? Has anybody built their own setup? I feel that I'm pretty capable of building my own setup, and the machining capabilities that I don't have in the shop is available through a friend across the street.

Thoughts? Comments? Suggestions?

 

[Mt_Man]

https://www.garagejournal.com/forum/showthread.php?t=24280

This guy is a wiz kid and super nice. He talks about centrifuging oil like you want because he had the same and others issues. He talked about ash build up in the burn chamber. From the Carbon? I don't remember on what page he talks about it. Also he has a neat heated header tank and pump system. He did a couple vids on youtube too. There are a bunch of people that have made there own single pass centrifuges over the years. Youtube has bunch of videos. I almost did that. They can be really simple. Opted for turnkey setup because I didn't have a shop to make one. I think simple centrifuge will even sell you just the bowl. I like the ultimate force design the best out of all of them. That will be the one I get when I upgrade.

http://www.simplecentrifuge.com/ordering.html

Then you just make your own motor/housing kit. So far I have only run a single pass centrifuge 2-5gph. With no fuel related problems. My buddy runs his single pass several times till he only gets a little sludge in the bowl. Then he calls it good. I would think that you would not need to be that thorough. I also started using a 1 micron sock filter to do QC on at the end. You could use a sock filter too. The carbon is going to be hard to remove. My system doesn't get it all out. Settling like your doing is a big help. As for cleaning interval. I started by checking early and see what had build up. Then over time I saw how it built up and time. New batch of oil get about 4-8hrs then max I go is 12-20 hrs between cleaning. Seems to work for me.

I like the idea of centrifuging into the primary tank. You probably thought of this. How about using a continuous flow centrifuge and setting up the valves and pump so you can pull from the storage tank and also recirculate on the primary tank when its full. The recirculating would then continue to clean until satisfied. In the mean time you keep the fires going. Or could get a cheap tote and set it up as an intermediate filtering tank. Then it is a fast pump to fill the primary tank. Smaller continuous flow fuge is around 55gph I think. You could go bigger and get something like 150gph+. A float and switch would be easy to rig up.

Craigslist(other online places) sometimes have used centrifuges. You might be able to find a continuous fuge from a big rig junk yard. They sometimes put them on big rigs/buses.

Can you get a finer filter before the burner? Is the nozzle cleanable or just replace? Siphon or pressure nozzle?

 

[Booyah45828]

Thanks for the link, gives me more spare time reading material. And I definitely love to read about a good DIY project. Thanks for letting me know your process too. It really gives me an idea on feasibility.

I'm looking for used stuff, and might have found one on here actually.

I actually never thought about the continuous flow. Maybe do two fuges, the continuous flow and then maybe have a trickle out of that into a heater and into another fuge that's on a timer. I really don't like the idea of a heater being on 24/7 while I'm not in the shop. And I don't like the idea of a float switch either. We had a transfer hose between the tanks on a float switch and the float stuck once and made a mess. Never again.

The setup is versatile, with no real space constraints, just financial ones lol. A 1 micron sock filter after the fuge and into the primary tank is a good idea. I can go smaller micron on the filters, the final pre-burner filter is a 1772 lube filter, and with those specs I found a 16 micron and 10 micron filter option with the same thread and gasket dimension. So after this one is used for a while, I'll likely switch to a better micron.

The nozzle is cleanable, and you're supposed to clean the ash out of the box and chimney annually. I typically soak the nozzle in our solvent tank overnight, and reassemble and install it in the morning, It's just doing that once a month makes a mess and leaves me to believe there has to be a better way. And that way is burning cleaner fuel.

 

[Booyah45828]

I guess I figured if I ran it slow enough, and a fuge with high enough trash capacity, I could get pretty clean oil out of it. I've heard some fuge's spin so good that the additive package is pulled out. I figured if it can do that, it can remove the fine carbon/sludge from it and solve my dirty burner issue.

I was thinking that if I could filter 5 gallons an hour, at 8 hours a time, and have pretty clean oil, I'd be golden.

 

[Booyah45828]

Just got the idea to look up fuel filters in the size I need. Found the 4347, that is 10 micron, similar width but a few inches shorter, and for half the cost of the 1772 lube filter. Big thing is there are 4 on the shelf of my local napa, so I think that's what I'm going to run

 

[Mt_Man]

Your welcome, Cool cool, wmo is a rabbit hole and lots of potential lol. Have fun with it! That is the most important thing for me haha. The single pass fuge can be varied on flow rate. The continuous(I should say it is a pressure driven fuge) flow can't really be varied that much. The flow rate changes the rpm which changes the g's and the cleaning ability. I saw a guy that set up his pressure driven fuge so he could move it around. Clean a batch of fuel. Then he moved it to his truck's bed tank and filled it up with the last pass through the fuge. The pressure driven fuge works by cleaning the oil over and over again. Eventually all the oil will be passed enough times that it no longer has contaminants. People have set up a batch system, run/clean enough times that it no longer pulls sludge out. Others have separate containers and filter back and forth till its clean. This insures that the oil all makes it through the fuge each time and nothing gets missed. Not sure which is better.

I would think that centrifuging the wmo would be way better then just filters and wouldn't need a sock filter. I have seen some guys use sock filters just hanging and let gravity pull the oil through. Slow process. Also for heating. How warm is the shop? Pressure driven fuges tend to need heat. Cold oil just doesn't like to flow through the small jets at the bottom of the rotor. Not sure what the minimum temp would be. 70-80 degree f might be enough. I run my single pass without heat most of the time just run it slower. But I am also cutting my wmo before I send it through. You can make your own heater that goes before the pump then your only heating the oil that is getting fuged. Eventually the whole batch will get warm if insulated well. But I was thinking if the shop is warm enough then oil might be warm enough not to need to heat. But that doesn't seem like it would work after all. One thing I have been interested in trying is two single pass centrifuges in series to see if the second one pulls anything out. This would prove how well the first one is doing.

I got my sock filters from utah biodiesel supply. He has some that are 98% efficient.

This guy has a good write up on wmo too.
https://usfiltermaxx.com/en/content/9-make-black-diesel

Pabiodiesel has some interesting youtube videos on centrifuge comparisons. You probably watched them already.

That is nice you got some filter options. Wonder how much the shorter filter will restrict the flow of the oil. Worth a try for sure. The WVO guys all about the big fuel filters so when the oil is cold it will still have enough flow. At least that what would make sense to me.

Man that would be crazy if fuges did pull out the additive packages. It will definitely get some of the carbon out. It is really gross to see what they pull out. It will make you not want to miss another oil change lmao.

 

[Booyah45828]

Shop is 70+ degrees most of the time.

We have an excess (1000+ gallons) of oil right now, so there's no sense in not having it hot. Otherwise we have to pay to get rid of it. We also have a few other farmers and shops that give use their used oil too. An excess might be an understatement.

So if this goes well, I might burn it in a vehicle. Talk about a rabbit hole.

But the primary is clean oil for the furnace. I've watched all of the PAbiodiesel videos, and watched a bunch of other youtube videos on this. You want to talk about mild to wild lol. One guy must have had $10k in just centrifuge equipment in operation, and the oil he was burning looked as clean as the stuff out of the bottle.

My plan for now is to take the oil out of the tank, to the old furnace pump and 100 micron screen, into the old furnace regulator down to 10 psi, which will trickle oil through a 120v heater and into a 120v centrifuge. Fuged oil will then transfer to the primary tank. And that will all be operated off a timer of some sort.

If I can find a 2nd fuge that would run strictly off the old furnace pump output, I'll install it in place of the regulator and have a trickle of oil come out of that and into the 120v fuge to then. I'll then have the old furnace pump run near constant, only turning off to clean.

 

[Mt_Man]

Nice man, you are set! now you just need to figure out other uses. Greenhouse, hot tub, sauna, etc lol

Yah some go above and beyond. It would be nice to have that clean of oil haha. I use stacked totes and gravity to flow through my centrifuge. Your setup should work. Keep us posted, like to see what you can scrounge up!