Running a Clone on #2 Fuel Oil

[OilCanMarkus]

Hey Guys,
I've got a 25Hp ChangFa clone that has successfully been broken in for 50 hours on regular diesel.  I've changed the oil (which came out without any sand or shavings).  I've got about 300 gallons of fuel oil in a typical oil tank, with filter (which used to be connected to a Weill McClain boiler).  I'd like to know if anyone has run these types of engines on #2, and what adjustments if any were made.  I was thinking about changing the filter to a finer grade, and perhaps running the oil through copper tubing coiled around the exhaust pipe to pre-heat it and thin it out a little...

What do you think?

[cognos]

#2 FO is very close to the same distillate as diesel fuel.

The difference is it has no performance-enhancing additives, like a detergent, cetane improver, corrosion inhibitor, for example... The spec for #2 FO allows for a slightly heavier "tail", meaning it is OK for it to contain some heavier compounds than are allowed in diesel - but in my experience here in North America, I've never seen a refinery adjust for that - they pull the #2 and the diesel feeds straight off the tower at the same time as the diesel from the same place on the tower. Doesn't mean it doesn't happen, though... but I would expect the performance of both distillates to be indistinguishable in your engine.

Depending on season, diesel may go through a few "finishing" steps that #2 FO may skip - like drying or filtration.

Just my opinion, hope this helps.

[cognos]

Oops - almost forgot...

It's possible the #2 FO has not been hydrotreated to remove the sulphur - as most diesel has these days. I can't see that it would matter much to your chinese diesel, as I'm sure they run all kinds of high-sulphur fuels around the world... hydrotreating also saturates the carbon-hydrogen bonds, so it makes for a more stable diesel fuel with a more predictable distillation curve.

But I thought I'd point it out, as it is in fact a major difference between #2 and modern ultra-low sulphur diesel.

[cognos]

It's pretty dry to begin with... the stuff never drops below much 350°F at any time until it gets to the storage tanks  - but during processing, it comes in contact with steam and liquid water at many stages, various temperatures and pressures...
Water is removed from accumulator drums at every stage of processing. At high temperatures, the water drops out pretty quickly and cleanly.

Diesel is futher dried by passing it through demister pads in vessels, expanded metal filters, "drying towers" filled with ceramic balls, salt filters, the water drops out and is drawn off. Even then, water continues to drop out in the strage tanks,, which are held around 100° F.

The driest diesel is made during winter months for consumption in the north - it is very dry, and has a higher standard of cetane testing.

if reference quality fuels are required, they pass it through silical gel filters.

[OilCanMarkus]

Thanks for the good news on the #2! 

I'll give it a test run in the engine's small tank before doing any major hookup to the large oil tank and filter.  I've read about some old but good oil filters that use rolls of toilet paper, and are said to do a much better job of getting the gunk out of dirty oil (either as a pre-filter or as an in-line filter between the engine oil pump and the high pressure distribution line to the rest of the engine.)

If anyone knows where to get the T.P. filters, drop me a line.  Otherwise I'll post my test run results on the #2 when I get some time to tinker...

[veggie]

Jens,

Consider a simpler and cleaner method of drying.
Heat the oil to near 200f and spray it across a stream of air.
I built a drier for biodiesel which incorporates a small pump, drum "band heater", and a 1/16hp mini furnace blower.
I fabricated a nozzle by crushing the end of some 1/4" stainless tubing and soldered it into a pipe fitting.
I tested the nozzle first with water and a garden hose to get the right pattern.
All the drying and spraying is done inside a 15 gallon drum so there's no over-spray or mess.
Two ports in the top of the drum.... One for air-in and one for air-out.
The nozzle (and pumps) sprays hot oil across the incoming air stream and the exhaust air carries away vapor.

Probably works quite well for WMO also ?

Veggie

[cognos]

I've read of the spray-drying method used by some DIYers... I'm sure it works well... my only concern with this is the possiblity of a static charge igniting the spray... atomising oil through a nozzle is a great way to build static, and could be hazardous in a semi-enclosed metal drum with all the atomised fuel and air... all I can say is, make sure everything in sight is bonded together and grounded well!

Not to mention - hot oil + air + atomisation for maximum surface area = high probability of oxidation = gums, varnishes, other possibly unwanted reactions...

Silica gel will dry your oil well. It's a question of capacity - how much silica gel will you need to dry a particular sized batch of oil - and how will you regenerate it? Silica gels have a apec that will tell you how much water they will hold. One would need to figure out how much water is in the oil.

If your oil contains a fair amount of water - in the lab, we would test for this with a centrifuge on a 50 ml sample, read the result and multiply by 2 for a percent water - you will need a large amount of silica gel to adequately absorb the water.

There is a product out there that turns blue when it's saturated and needs regeneration. It does take some energy to regenerate it. Might not be worth the trouble...

Silica gel can indeed be water-washed. This is how a silica drying tower is regenerated at the refinery. It's hot-water-washed, then steamed out to remove any liquids. After it is water, oil, and vapour free, it's regenerated by blowing through the tower with high-temperature air at around 400°F.

I'm not sure how this could be efficiently done in a home setting...

I've actually seen, on some bio-diesel site that was selling these "magic beads" for drying your vegetable oil (blue silica gel), a regeneration procedure that required you to get an old kitchen oven and put it out in some field away from your house - put the magic beads in a roasting pan, put them in the oven, set the temperature, and stand back! Apparently there will be clouds of white smoke (ya, no kidding...) for a while that they recommend you not breath... when the smoke quits, wait 15 more minutes, and voila! regenerated magic beads!

Not what I would recommend...

[BruceM]

Would any of the additives for water in diesel fuel be effective? With gas, alcohol is used to keep the water dispersed;  if that would work in diesel then it might be less energy/labor/processing cost to just add a bit of alcohol based on batch water content test after settling. 



 

[veggie]

The concern I have with gels and beads is disposal.
The spent media can no longer be poured into the local used oil depot tank and the solids certainly should not be dumped at a landfill.
So where would it go ?

Veggie

[cognos]

Where I am in Canada, there is no restriction on non-industrial-sized loads - up to 5 gallons by volume - of spent silica gel going to a regular dump or waste transfer site - and if it's just water that it's been used to absorb, the stuff is as benign as sand in a landfill...

In the county where I live in Ontario, there are household toxic waste dropoffs held twice per year - they'll take almost anything as long as it's in 5 gallon or less containers.

I can't see how one could truly exhaust a silica gel bead to the point where it would need to be disposed of in a landfill, by simply exposing it to vegetable oil or another oil just to absorb the water. It would just need regeneration to return it to use...

Yes, silica gel can absorb some pretty nasty stuff, which would make the spent silica gel toxic - but none of these nasty chemicals *should* be present in your fuels...

If disposal is truly a concern, if it were me, I would burn any spent silica gel beads in an open firepit with a good fire  - and just spread the remaining ash around as normal.

The environmental disposal hazard of spent silica gels would be of less concern to me than the actual exhaust of an engine burning WMO, or any other mystery fuel.

There are additives that one can buy for diesel fuels that may make water removal faster or more efficient. If it's designed for this purpose - water separation - for diesel, it should work for WMO. All bets are off for additives used in SVO or WVO.

As far as a dispersant in a diesel fuel - used to keep water in suspension in an oil - these are designed for water in parts per million in the fuel. Much more than that, you need to remove free water which can be a killer for a diesel.

Water in a gasoline engine is much less critical, and alcohols can be used to bind with the water so it can be passed safely through the combustion event.

Again - this is just my opinion based on what I know about fuels, additives, and processes. I have next to no practical first-hand experience with the engines, fuel, and conditions you guys are running with.

[cognos]

Depends on the actual free water content... see above...

[cognos]

I can guarantee you that there can be "free" water in oil samples that are visually clear. Free water may cause haze, and it might not... if you have enough water in your raw sample to cause water haze, you will need a fairly effective process to dry it - that's a lot of water!

It is free water if it isn't chemically bound - or in solution - or in what's called an "azeotropic mixture"... it's a moving target...

A water droplet will adhere to a "dirt" particle due to a difference in electrostatic charge, but is not "bound" to it.

In the trade, if it can be separated out by centrifuge, it's free water. Without a centrifuge, one can only guess at water content. If you want to be accurate about how efficient your favourite drying process is, I'd invest in a small lab centrifuge.

Haze can be caused by many things other than water, both organic and inorganic.

An example of inorganic haze could be bentonite clay particles. There will be no change in haze on raise of temperature - but inorganic haze will settle out in a centrifuge test, and is measured with free water as "BS & W" - Bottom Sediment and Water. One does this test on a sample first.

Once the BS & W have been removed, one can check for organic Haze.

An example of organic haze could be microcrystalline wax particles - and this is what the "Haze" specification for lubricating oils and fuels tests for. Wax haze goes away if you raise the sample temperature.

Water drops out in the fuel filter because the fuel filter is acting as a "demister" - by design, it is actively coalescing all the microsopic (and quite possibly invisible)  water droplets into bigger droplets that are now heavy enough to settle out by gravity. Most fuel filter media is chemically treated to make this happen, and not be destroyed by contact with the water.
That's why commercial filters for oils are better than toilet paper - toilet paper isn't treated with anything that will assist this process, and wet non-standard paper filtration products can liquify (indeed, designed to be easily broken down by water) and pass out of a filter canister - I can't imagine this will do an engine or fuel system any good...

[BruceM]

Very interesting, Cognos, thanks for the explaination.  Sounds like a test tube centrifuge would be a very useful tool for analyzing odd oil fuels; catch a water or fine sediment problem before using a batch.  

Ronmar warned me off of using Bounty paper towels in my Listeroid gravity oil filter couple years ago, as you have noted, he also reported that plain paper products break down with moisture, etc.  I switched to cotton rags.

[cognos]

When I speak of a centrifuge, I'm talking about one for lab testing - room for 50 samples, 10 to 100 mls in special tapered/graduated pyrex cylinders, variable speed, temperature controlled, timer, etc,... - I figure the one I used to use was worth, oh, 30, 40 grand... mind you, that's Canadian dollars, so, cheaper in the States...

With a test centrifuge such as this one - one can be assured that all free water will be removed from a given sample, even a difficult emulsion. Just turn up the temperature, turn up the rpms, add some demulsifier (we called the additive "knock-out drops" because it helps "knock-out" the water and solids) - and wait for the timer to beep. This thing was in it's own concrete block room, we called it the "blast box"... can you guess why? A single failed 50ml sample container of crude oil can make a hell of a mess at 5000 rpm...

A home user only needs a small one, a desktop unit for test-tube-size samples.

The sort of continuous centifugal filtration you are speaking about - like the Dieselcraft, ferinstance - I have no experience with one, I've read a bit and they do seem to work well for some.

As for the fuel filter - most are only designed to capture minute amounts of water in large amounts of fuel - how often do you need to change a fuel filter running conventional fuels, due to water? They are a last resort. I suppose you could put a few in series - what doesn't get caught by the first would be caught by the second (or third, or fourth...). If you get the clear ones, perhaps this could be a visual indicator of your fuel-drying techniques' effectiveness.

If it were me, I'd try very hard to remove all water from my chosen fuel before introducing it to the engine...

[rl71459]

I have been watching a centrifuge on ebay.... I use the exact one at work... It works great for testing
for water content in oil (Machine Oils of many different types and viscosities) as well as other contamination. He is currently asking $49.99 it was at $75.00 in a prior listing. I dont see the speed
control in the listing but it may be there... It says it works.

Ive been to cheap to buy it! But if it's complete it's a good unit for one of our forum members.

Rob

forgot the info
SERVALL ANGLE CENTRIFUGE WORKING

Item number: 270487151123