I've been thinking about oil, both fuel and lube.....

[GuyFawkes]

and of course those of you running veg oil etc.

Now, there's three things that bugger up a fuel oil or lube oil.

1/ water
2/ particulate matter
3/ liquid impurities

on the boats we used to use alfa-lavals to clean up fuel, magic toys, but crazy money as far as we are concerned.

Now.

The thing about a lister(oid) that you just have to accept is that there are periods in the duty cycle where it is not doing useful work, that puts "us" in the position where we not only have "free" power available, we actually have power going to waste.

from here I'm mainly talking about fuel oil, but this applies eaually to lube oil, and I'm especially thinking of the WVO boys.

WATER

it is going to get in, no matter what you do, so the question you have to ask is how much water you have in your fuel, not if you have any at all.

You can get >99.9% of water contamination out of oil by the simple expedient of applying a vacuum, an old edwards type pistin vacuum pump will do the job nicely, either belt drive it from the motor or drive it electrically, 1/3 rd of a horsepower, leave it running 12 hours, all you need is a container (or series of them) capable of withstanding a good vacuum.

This method uses surprisingly little power per gallon of fuel processed, remember there is no penalty here for processing ten times the fuel, just a small time penalty for maintaining the vacuum.

This method will, to all intents and purposes, remove 100% of all water, just leave it under vacuum longer.

This method is potentially BLOODY DANGEROUS if you try it on "aromatic" or vaporising fuels, guess what the vacuum pump outlet port will be ejecting...

SOLIDS

Big uns you can get out with a screen, smaller ones you can get out via centrifuging, very rapidly.

LIQUID IMPURITIES

You can get a pure single grade of oil out if you centrifuge it hard enough, most of the expense of an alfa laval is in the opening drum and self cleaning design, we do not need that.

centrifuges - where can I get one from?

well, your 25" flywheels spinning at 650 rpm

diameter is 78.5 inches, x 650 rpm = 51,025 inches per minute = 70.86 feet per second.

the force depends on the mass, eg density per cubic cc of fuel, specifically of the different weight oils mixed in our potential fuel

force = (mass x ( 70 fps squared)) / time

if you like this sort of math look at http://www.antonine-education.co.uk/physics_a2/options/Module_7/Topic_1/topic_1_rotational_dynamics.htm

bottom line here is your flywheels are large and fast enough to do preliminary filtering of fuels.

for final filtering you'll need a higher power spin, but you can get this from an electric motor spinning at high rpm

seem to me this is doable for a DIYer making his own fuel from rape seed or WVO and well financially viable.

thoughts?

[Mr Lister]

GF and List,

Here is a quick question - can you distill veg oil?

If you put a pan of oil on the cooker and it gets a bit hot it starts to smoke. Can you condense this oily vapour on a water cooled coil and use the condensate as distilled fuel?

Just a thought.

Like the idea of the centrifuge.  I would make it the size of a bean can and put a 1" pulley on the shaft and spin it at 24 x 650 rpm from a belt off the flywheel.

You only need to centrifuge a couple of pints of fuel per hour to keep up with the engine demand, so why make a thing the size of a spin dryer whe a bean can will do?


just my tuppence worth,


Ken

[Mr Lister]

GF and List,

Another thought occurred inspired by a trip to a commercial vehiclescrap yard last week.

Most modern alternators (90 amps +)  from diesel engined vans have a splined shaft coming out of the rear of the alternator that drives an integral brake vacuum pump. Did someone mention vacuums? 

Added benefit they all use serpentine belt drive these days.

With 3" pulley on alternator, the rotor is going to be doing 8 x 650 rpm  which might be enough to run a centrifugal fuel dirt extractor.


Ken

[rgroves]

GF and List,

Here is a quick question - can you distill veg oil?

If you put a pan of oil on the cooker and it gets a bit hot it starts to smoke. Can you condense this oily vapour on a water cooled coil and use the condensate as distilled fuel?

Just a thought.

Vegetable oil doesn't fractionally distill like crude oil, not so far as I know and I've  studied the vegetable oil question a good bit. But a little methanol and lye will pull the heavy stuff out so readily, and for a Lister you wouldn't really need to get your biodiesel to highway quality at all.

Or for that matter, if some waste heat applied to the vegoil will let it spray through an injector like diesel fuel?  It works in Greasel conversions on passenger vehicles. 

[SHIPCHIEF]

Distilling is to wasteful of energy, and possibly unsafe.
You could use the jacket water waste heat to preheat the WVO storage tank. Even tho it would be below boiling temp, a very modest vacuum would suck that water right out, and the tank wouldn't need to be so robust. Check your steam tables (Thermodynamics book with graphs) Water boils at about 85 F at 28.5 inches of mercury vacuum. (memory here, so excuse minor errors). But if the water in the fuel was 190 F it wouldn't take much vacuum at all. Some compromise temperature that is safe, but still effective with reasonable vacuum?
Also, cellulose will remove water from oil. About 6 ounces of water per roll of toilet paper according to one TP filter salesman.  The depth filtering of TP might clog too fast on WVO, but you really need to filter the dickens out of anything going thru fuel injection. So use a strainer, then a coarse filter, then a fine filter / water absorber.  Burn the dirty TP rolls in the fireplace to start the firewood. Free fuel is not free. But it still might be worth it.
At least you guys that make Biodiesel could use the engine waste heat to help remove the water from the feedstock before you add the methanol and lye.
Scott E