No worries Tom. The simple answer is, I'm still working on it.
If you want the long answer
I've run the filter with both pre-filtered ( down to about 50 microns if I'm lucky ) veggie oil and used motor oil. The system is primarily designed for used motor oil. I've got farm plates on it, so I can carry up to 502 gallons of the stuff, no permit, no EPA. Its a 200 gallon tank designed to carry as much as the truck will hold. Its a F250 but it holds one ton just fine. Given my millage before the rebuild it should give me a range of about 3000+ miles. Basically one good road trip. I prefer the used motor oil but veggie works as well, you just have to be careful about engine temps.
The centrifuge might not be a part of the final configuration, it puts a lot of strain on the system. I might add another pump but its probably not worth it. The filters work best in the 20lb range with no more than about 4lbs cross pressure difference, or the pop valves go. Other than on that first filter which has about a 20lb pop valve in it. The purilators are excellent filters but they are a little delicate. The centrifuge runs best at 100lb so you can see where sneaking up on 100lbs with no more than 4lbs cross pressure difference might be more trouble than its worth. Without the centrifuge there is no constriction in the system. free flowing 1/2 inch lines right off the head all the way. The double filters means that the flow is halved at each filter, slower = better in this case.
the filters run orange ( ~20 microns ) white ( about 5 microns ) gold ( about 1 micron ) then into the centrifuge and then into the big water separator and from there back into the tank. There is an overpressure bleeder valve ahead of the filters that sends excess pressure back to the tank. There is a baffle in the tank that sorta separates filtered from unfiltered. Actually I just return to one side and draw from the other.
The centrifuge arrived stripped from the factory and although they didn't want to believe it they agreed to take it back, that was months ago and I've not had the time to get to the post orifice. I know I'm a procrastinator and I might have lost my window of opportunity on that one but oh well. I don't think I really need the centrifuge anyway.
There is also an exhaust heat exchanger going in ahead of everything. So my pumps gotta be running pretty much whenever the trucks running. Although I don't think my exhaust gas temp at that point in the system is ever going to be above the 300°C mark which is the low end of the boiling point for motor oil. Might boil veggie tho, so there is a bypass going back to the tank where pressure can bleed off at the cap. I hope, wish me luck on that one.
The viscosity issue is also kinda critical. The pump and all quick connectors are above the level of fluid in the tank for safety reasons, but it means I gotta watch the viscosity of the fluid. I've got about 100 gallons of veggie oil in the back yard and I'm planing on cooking up 20 gallons at a time into bio-diesel and mixing it with the motor oil. Should do the trick at 1/10 which is probably a bit much but I also want the cleaning properties of the bio to help keep the tank clean and the gunk in the filters where it belongs.
I'm also working on a pyrolysis system and just frak the motor oil directly into diesel but thats down the road a bit. Gotta finish the truck first. Thats also not an onboard system, Thing about Fraking is that I could use shredded tires, which has a friend of mine on capitol hill's interest as the states awash in tires. Long story for a different thread but I've got an economically viable way to produce vehicle grade fuel from used car tires. Its small, clean, cheap, and it works. On paper. ;-)
I really like the two battery set up, ( hope you all forgive me for thinking out loud on this thing, but I can always do a better job if I get a little consulting time in ). I'd seen it before but I was hoping I could avoid the charging issues, maybe by simply going straight off a 24V alternator,. I'm now thinking its more complicated than simply hooking up some heaters as resistors in the two bat system posted above and I appreciate all the help
I am concerned about uneven discharge on the bats and would love to hear more about how that diode bridge goes in. I'm not completely unfamiliar with electrical systems but if you could run me through the logic I'd appreciate it. I know what they do, ( only allow the flow of electrons in one direction ) but how they are sized and how compatible are they with the internals on the batteries.
I'm generally not to bad with electronics as long as its thoroughly explained, For instance are we talking about schlotsky diodes which require a heat sink or those little round ones that are designed for pretty much no voltage.
Dam I just thought of something, I need both bats under the hood at 12V, Basically I can't rewire them in this configuration and still provide enough cranking amps at 12V. I'm back to square one. 24V alternator and two more bats, voltage regulator, Dam I really don't want to have to do that tho. Maybe I could just use that slick wiring trick on the two bats in the back and charge them off the 12V poles and use them off the 24V poles. I'd need a bigger alternator,
Oh well hope that answered all your questions.
cheers
next time I build this thing I'd run a big 4" helical exhaust tube through the tank itself, as it is I'm trying to figure out how I can both pump fluid through the exchanger or have it work by convection, without modifying the existing tank. Which would mean draining what I've got in it now and cleaning out the tank so I could weld and cut on it. I suppose I could just fill it with CO2 If it was just welding but, I get nervous about the occasional explosion.
That's some great schnitz Boston. I polish diesel fuel as one of my services, so pumps and filters get me aaaaawl spooled up!
In the two battery system, I wouldn't worry a whole lot about uneven drain. Batteries basically level themselves out, like liquid in two uneven tanks limbered at the bottom. Unless you're abusing the system in some manner, not paying attention to battery health, like proper fluid levels, frozen temperatures, pulling their reserve too far down, or over heating them, there shouldn't be too much dilemma.
As far as the battery isolator/combiners, simplistic explanation, they're just basic diodes and resistors with a charging post in the middle of a fairly good sized heat sink- usually aluminum if I'm not mistaken. They do use some power as does a converter, however, typically not as much. Remember though, the combiner will only separate one voltage, not two. I personally think they're a waste of time, but, they do keep a bad battery from dragging down a good one. You usually see these things installed after there's been an "incident" and someone selling up a "system".
What I would worry about most is charge(you even realize that in your reply to me), not volts. Making sure your alternator is putting out enough amps to replace the watts used by the pump. With 200 gallons of veggie, it will pump slow- I'm guessing at best 6 gal/min, even with a gear pump, although you've got nice fat hoses to reduce restriction. That's 30 minutes, optimally, on a full tank of veg.
I see your heat issues, why not just plumb in your coolant water? Good flow, no weak spots created from high heat, as in exhaust systems-welds will fail faster with exhaust heat than coolant heat. You could use a heater coil out of a small 10 gallon hot water heater. Open up the top of the tank, install the water coil and bolt on a tank inspection plate. You could even weld into the inspection plate, the fittings for the heater coil, this way, you don't risk welding on a used potentially flammable tank, especially down low where a tank/weld failure could result in 200 gallons of waste motor oil on the streets.
BTW, splitting the exhaust is a no-brainer, you can even use stainless flexi-pipe to route the system. Although not too smart, it would be kind of fun to see the exhaust coming straight up through the top of the tank...vibration will kill this system, I'd avoid using exhaust as your heat source through the tank, better to pump hot water through.
BTWBTW- The batteries in your system, I would use dual purpose deep cycles. That is, starter/house type batteries. I can easily see you pumping for hours, used veggie out of some restaurant in the snow judging from your home location.... that will take some time, well over the 30 minute guesstimate I made earlier, you'll need good batteries and great alternator.... maybe even one of those 300 amp ambulance rigs I keep reading about on here. I prefer Trojan brand deep cycles, but I'm sure you've got some good brands too.
BTWBTWBTW- those centrifuges work really well....ESPECIALLY!.... on used motor oil. A magnetized 20u coalescer/filter, followed by that centrifuge, then filtered down to 1u is a great system. When you install the magnet and large filter first, you limit the particulate in the centrifuge, this will save you tons of money in smaller filters when doing the process you're describing. Those 'fuges are pretty awesome. The kewl thing is, they can bolt right into the top of a tank and just dump clean oil back.
The only reason I'd put the 20u filter in place is to house the magnet and reduce the amount of crud the centrifuge has to deal with. When pulling fry oil, there can be a lot of sediment to overwhelm the 'fuge. Large quantities of used ATF and motor oil can have the same dilemma, except metal filings. Since you're doing this in the field, that is how I'd set up the filter arrangement. If you were just pumping raw oil into the tank for later processing, then who cares, other than keeping the bottom of the tank clean and parts out of the pump.
Why are you reacting the veggie, instead of running it straight? Seems costly in time, hazards, and money. Running straight veg at proper temps avoids all the hassles, plus the added benefit of additional lubricity and lower engine temps, with similar torque- if not more- as DFM#2.
I like your used motor oil idea with reacted diesel though. I think that is pretty kewl, stretching out the reacted stuff to reduce some of the negatives of reacting mentioned above.
