My Used Oil Isn't Flammable Any More So What Did I Contaminate It With?

Maybe water...I assume you have a drain on the bottom, I would drain some out and check....pics maybe?

What is in the "used oil" tank? Fresh fuel oil, used motor oil, cooking oil, something else?

You might consider a specific density test to help in identifying this fluorescent yellow green liquid. No wait a minute, didn't you say that it was dull red color and smelled more like a cheap merlot when you found it.

I'm just having a little fun with you. My real guess is that you do not have oil in your tank. It could be condensation water or a non-oil waste lubricant you were given as waste oil.

I'm glad to hear that your back is better.

What I have is about 90% used motor oils from vehicles and tractors. Mostly 5W-10 to 20W-50 weights.

The rest is used hydraulic oil, transmissions fluids, and synthetics with some old diesel fuel and gasoline as well.

I have a water trap and so far nothing major has ever shown up. Relating to directly having water in the system that tends to make the used oils milky or cloudy when shot through the nozzle at high temps Of which even then it usually will burn anyway being the water flashes to steam as soon as it leave the nozzle. The problem is what I have here looks just like normal oil does but yet wont burn.

Before anything goes in the bulk tank it sits in 250 -300 gallon totes for at least two weeks to settle out first which so far has worked great for getting the heavy particles and water out. When I transfer the oil from the tote tanks I always pump it from the top down and stop before I get to the bottom.

The only thing I can think of is that the last batch I got had a large amount of ethanol in it and that is keeping the water in solution where it can keep the oils visual appearance looking normal but changes its ability to burn.

It's the only rational thing I can think of being I am fairly diligent about letting everything settle out first and filtering it before ever putting it in the bulk tank.

Like I said earlier visually it looks just like old engine oil, feels like old engine oil and smells like old engine oil. It's just apparently slightly more dense and wont burn.

BTW the screwed up back is a real pain in the back side in more ways than one. I really hate toilets, and socks, and shoes, and stuff on the floor, and chairs, and showers, and my feet are too far away when my back is out!

Seriously when you have torn muscle around the L4 and L5 vertebrae the toilet is one miserable torture device.

Right now I would say I am at 50% at best. It still hurts to walk and sit and getting our of a chair or standing up is still slow and at minimal very uncomfortable.

I would try draining the bottom few inches out of the tank, flushing the line and try it again.....

water in an alcohol solution seems like a good answer, it wouldn't emulsify so your oil would look like oil. I would still think it would flash off as steam though at your preheat temps. Is there enough steam to extinguish / prevent the flame? perhaps. The pressure drop at your nozzle, may also just be enough to make it condense back to water.

Either change it all out or "Dilution is the solution to pollution" Drain off a tote or 3 and replace with oil from the new totes, give it a good stir and see if you can get a burn. Pain in the proverbial to do though.

I have a silly question, does the questionable oil float on water or does it blend?

Not silly at all. How it reacts with clean water is the first thing I'd test. S.M.

You might try changing the nozzle on the unit to atomize droplets finer. I had an unit that had similar issues and that fixed problem. Just a thought!

This is a good point and might actually work.....but if you're me, I always start with the easiest most simple solution....

Well, providing given data is accurate, it's either water or silicon oil contamination the most rational possibilities. Silicon oil is not as common lubricant base, but Murphy says otherwise. And it'll burn, but will need much higher "preheating" temp.S.M.

Can you sample some from the middle of the tank, or possibly at various levels in the tank, to see what will burn?

.

I suspect everything getting so cold has caused whatever water was normally contaminating to concentrate in the lower portion of the tank. If something is working to keep it from separating, it may be difficult to distinguish visually or or by feel.

.

I'd try to find a level that does burn and then remove everything below that.

Couldn't be as simple as water in there could it?
Del

My 2 cents:

1. You say you have verified that the preheat is working, so the oil coming out of the nozzle is over 200 F. This won't burn with a spark or a direct flame. And the apparent viscosity is normal to what you expect.
2. If you take a cold sample fom the top & bottom of the tank and check them, are they the same viscosity, density & appearance, and somewhat normal to what you've seen before?
3. I'd tend away from water contamination. At your preheat it will be boiling out of the injector so you would see/ hear a steam hiss & the oil stream would have a foggy appearance, also the ignition inhibition would be minimal at these temps. Even with large quantities of non volatile alcohols (polyglycols etc from hydraulic fluids) that are hydrophilic a 250 F stream should still ignite in direct flame even if it won't sustain conbustion, and you would be able to tell if there was too much water. This is on top of cloudiness etc. as you've mentioned.
4. Asphaltics are a possibility that comes to mind, but you've mentioned that everything presettles. I would also expect them to ignite in a flame under the parameters mentioned, once solubilized in lower weight hydrocarbons. If it is something like this, enough to make a difference I think you might notice a difference between the 2 grab samples.
5. My fear is that you may have picked up a load with significant chlorinated or brominated solvents, or some form of fire retardent. Probably the first. If so the density may likely be high & the viscosity low, so the material & spray would look fine, but the halogenated lower volatiles would flash in the injector & not support combustion of the heavier compounds. EG if I dissolved asphalt in perclorethylene you would probably think it was perfect until you tried to burn it! A boil test will also confirm high solvent levels.

I think you got some of this stuff or similar. My back's out too.

http://www.super-lube.com/nonflammable-hydraulic-oil-ezp-60.html

http://www2.dupont.com/Lubricants/en_US/products/Products_Oils.html

Good thing to think about and thanks so far!

All of my used oil comes from local places that do vehicle and large truck engine oil and transmission fluid changes so that's the vast majority of where and what I have.

The gear lubes hydraulic oils and what not come mostly from our equipment and all if it gets the cheap stuff so non of that is high grade non flammable fluids by any means.

My bulk tank does have a circulation pump in it that normally runs when ever the boiler cycles in order to keep everything blended so that any smaller amount of inflammable substances tend to stay diluted enough to not cause problems however its been turned off all winter.

Right now I am guessing that one of the shops where I get my used oils from got a vehicle or tow in that someone had filled the fuel tank with E85 and thus wouldn't run right so they dumped that in their bulk used oil tanks where I then got a hold of it later.

Some of the used oils I get from time to time have old antifreeze and water in them which normally settles out but the more I think about it the ethanol from the E85 could have been in a high enough concentration to absorb enough water and old antifreeze to have contaminated one of my last totes I brought home and now after having sat for most of the winter in the bulk tank with the circulator pump turned off it may have settled out.

I know E85 fuel blends with used oils very well being I use it in a 80:20 oil/E85 mix ratio to thin out my used oil just enough to get it run normally in my diesel engine experiments.

I am starting to think that maybe ethanol saturated with water still blends with oils easily enough but has a density slightly higher oil so it all went to the bottom of my bulk tank after sitting the last few months.

If I am remembering my chemistry right an ethanol molecule will bond with a hydro carbon molecule on one end and a water molecule on the other and if so could that account for how I get a normal looking oil that can hold enough water to not burn but still not look cloudy?

I got it fixed! Sort of.

I did a sample test and whatever it is will mix fairly well with water and when put in a metal dish and heated with the torch it first boils and gives off a considerable amount of non flammable vapor that smells a bit like antifreeze. Once that boils off it burns just fine.

So from that I tried letting the circulator pump mix everything in the bulk tank for about an hour then pumped about 5 gallons through the system to get everything flushed out in the filters.

From there it would burn moderately well. After that I switched nozzles from the 1.75 GPH 60 degree nozzle to a 1.35 GPH 80 degree nozzle and turned the injector pump pressure all the way up to improve atomization. So far it's burning normal but there is a light white/grey color to the exhaust now which normally burns nearly clear so I suspect that it's probably a bit of steam.

I am guessing the last batch of used oils I got had a large amount of ethanol and water/antifreeze mixed in it and once it sat for the last few months in the bulk tank with the circulator pump turned off it settled out.

Hmm. I learned something new today I think! (But my back still hurts like bugger though.)

Sounds like someone cracked a block. Your source must have been replacing an engine. Or, they got some of my used "oil". When I was a drag racer, my catch barrels of used oil had quite a bit of coolant in them too. I had two 55 gallon drums, but they looked the same and I didn't mark them. Quick engine change from one week end to the next often went like this - okay coolant drained, which drum is coolant? Oh who cares - gotta keep moving. Get a couple of loads like that and....

The white or gray color suggests antifreeze. You said you smelled it too. Glad you got it working acceptably.

I wonder if you got some oil containing PCB. The government ordered that PCB put in many oils to make them fireproof. Then they figured that burning people was better than giving them cancer, so the government decided to ban it from electrical components. PCB containing oil burns at much higher temperature than normal oil.

tend to agree with you on this welderman..The pcb would have settled lower in the volume overtime and would be more concentrated near the bottom of this storage tank..Ideally an oil tank would draw from the top of a storage tank but this would involve some trickier technology..Our oil furnace filter generally does a good job of keeping the particulates out of the burn nozzle but occassionaly the furnace guy has need to get us warmed up again by replacing/cleaning out that nozzle..(occassionaly being 1 in the past 13 years).

Best confirm that no-one and nothing has urinated in the storage tank first.

There is a family of oils that will not readily burn.They are heavier(SG) than water,and will not mix with water,water floats on top of them.

They have been outlawed for many years.They are called PCB's.

Is there a possibility that some used old transformer oil got mixed in with your batch somewhere?I hope not,but just a thought.

Greetings.

I haven't read any of the comments.

Got 2 minutes.

fuel to cold can gel.

We used to put 1 gallon of gas to 24 gallons of diesel to make it work in John Deere 410E extended hoe in winter in Western Washington because of cold weather.

I am interested in what your whole system is made up of. If you get the time could you shoot me a reply

Have a Great day,

Oly

CR4 ADMIN - email address removed

From the CR4 Rules: Do not post phone numbers or email addresses. The CR4 Admin will delete all phone numbers and email addresses posted in threads or comments. You can share this information via the CR4 internal messaging system.

A master mechanic not taking care of his own master mechanism. Ouch!

Well, poking fun is good now, as I have been there too.

I have little to contribute to the oil question, that much more to keep the body in shape, and to get it back to shape in a short order.

As we advance toward maturity, ahem, there are things we cannot do as rash and without preparations. Once I have learned, how the spine works, the rule was, keep it warm, get the sweat away any which way, warm it up a bit first. For me it was a woolen shawl twisted around my midriff. Then a loosely knit pullover, reaching down including my hips. It allowed me to work hard, wicked the sweat away, and did keep me simply warm enough. A thin windbreaker on the top of it, if needed, that's it. As the wrenched back is the result of chilled back muscles (that you do not feel) and a single (for it) inappropriate movement. It does not take much.

Now, that you are in the pickle, you need warm showers, sport gel meant for blunt damage (over the counter), and DMSO (over the internet, or local vitamin store). The last one (look it up Wikipedia, DMSO, Med/Alt.Med) is needed only as a mild local pain dampener. (Never mind other claims in research. Most of those never pan out.) Plenty of people use it such, especially in rheumatism. You smell a bit fishy afterward, but that goes away.

You take a warm shower. Dry off and cool down a bit. Get DMSO applied to the affected area. And, NO, your mechanic's hands do not qualify. You need really, really clean hands for that. Then some 15-30 min. later apply the sporting gel. Let it dry on. Now you are ready to go to do normal daily chores. Until the muscle fully heals in 1-2 weeks.

Then you are ready for more heroic action too. Remember, you are not 18 anymore, but slouching marching toward maturity. I do not ask you to act you age. Some simple considerations will suffice to keep the machinery in decent maintenance.

"I am interested in what your whole system is made up of. If you get the time could you shoot me a reply"

Sure. So what would you like to know about?

It's a custom designed boiler system I built about 12 years ago that first started out being a solid fuels multi fuel system intended to bun anything that is remotely combustible. Wood, Coal, Garbage, railroad ties, tires, or any mix of these things.

I use a Teco digital PLR system to digitally handle the intake draft to regulate the heat and automatically figure out the burn rates for the different fuels plus do automatic overheat and low fuel shutdown functions and tie the system into my homes heating systems.

The used oil system got added two years ago and is a simple direct drop in plug and play unit that I just swap out the boiler door to go from solid fuels to used oil fuel.

As far as the used oil burner system it's just a stock fuel oil furnace fuel injection system with the addition of a oil preheater built into the final stage of the injector plumbing just ahead of the fuel nozzle fits. Basically its just a piece of 1.125" dia x 3" solid copper block that has a 200 watt cartridge heater, thermocouple, and oil passage all in one piece.

To make sure the oil is properly heated in one pass the oil passage is 3/8" dia with a piece of 3/8" all thread rod in it which keeps the oil out along the edge of the passage and circulating along the threads giving it maximum surface contact in one pass. That little trick is key to making the whole used oil conversion of a stock fuel oil furnace burner work! Without it the preheater has to run much hotter,300 - 350+ F, and tends to cause a lot of oil coking which plugs up the nozzles rather quickly.

The preheater uses an off the shelf heater controller with dual outputs. One output controls the power for the heater cartridge and the other is a low temp warning output that switches a three way solenoid valve between bypassing the heater and nozzle or sending the pressurized oil to it once the minimum preheat temp of 210 degrees F is met. Basically all it does is keep the nozzle from spraying oil until the preheater is up to temp.

Relating to burning used oil a large multi stage filter system is necessary. I use a large 1 1/2 NPT fittings 150 Mesh cleanable screen unit thats designed for agricultural applications with a large 1 1/2 NPT 50 micron spin on cartridge type as a secondary filter. Both have water drains at the bottom of the filters. There is no need to filter smaller than 50 microns being that any particles that size are way below the clearances of the pump and nozzle and will pass right through without doing damage ever plugging anything up.

The reason for the large size filters is so that I have a lot of surface area to catch the unavoidable crud that tends to come with used oil. I also have four large neodymium magnets in the first filter assy to help catch any metal particles and rust from the tank.

Being based on a common fuel oil furnace burner system I can simply change out the nozzles to change my burn rate from around 80K BTU up to 500K BTU per hour by only changing one nozzle and readjusting the blowers air flow!

Is that enough?

Impressive design....this is the sort of thing that would be interesting to watch from conception to construction to implementation on the youtube....Good luck with the back, I sympathize....

Inventing things to make my life easier (and to prove people wrong) has always been my hobby.

Given the interest I have had in my boiler designs over the years I have been thinking about doing a full write up on how I built mine.

It's that dam time, effort, motivation triangle that I find to be so hard to balance that's the problem.

Here are a few pics of the system.

When it was brand new and first being installed! I wish my boiler room was still that clean!

The Teco PLR control unit. It has a 120 dB alarm that goes off if the water temp gets over 210 or if the water level drops too low. Both cases have automatic shutdown functions with self resets when the problem is fixed.

The base with the up daft plate assy. Its all solid 5/8" steel plate and the air comes in from the tube on the right side blowing out the grid of 1/4" holes in the 1" thick cover plate.

The solid fuels draft door. It's a two layer steel plate design that has 1/4" holes all along the perimeter of the inside of the door to produce a stable clean burning flame above the solid fuel. It makes burning materials that produce a high level of outgassing (Railroad ties, tires,coal, punky and green woods) easier and more stable.

Burning lignite coal.

Burning hardwood pallets. Cut into thirds and stacked. You can sort of see the door draft holes here as well.

The flues. The hot combustion gas comes up through the back of the bottom then forward then does a 180 turn goes back then up the 8" 14ga stainless steel stack.

The mechanical temp gauges. The stack temp normally runs around 450 - 800 degrees F during heating cycle depending on what fuel I am burning. Used oil is around 450 - 500 and coal or railroad ties push up to around 700 - 800. At idle burning wood or coal the stack temp can drop down to around 250 F.

Great system.One suggestion:Have you considered using the exhaust gas to preheat the incoming fresh air? Some large commercial coal boilers use this with a separate fan for each.A forced draft and an induced draft fan, with VFD.They use a double walled exhaust pipe,with a spiral between inner and outer to enhance heat exchange.

Not really necessary. Beng the intake draft comes from the boiler room which is usually around 70 - 90+ F its not really a much of an issue.

More than anything the issue is keeping the stack temps high enough long enough to keep creosotes from forming which on occasion has caused me to have to do a deliberate stack firings and burnouts to clean.

When done at night it's a wicked spark show and the whole stack will glow dull red with a roaring orange white jet like flame that can get to over 5 feet high sometimes!

Here is the used oil burner system. Its built out of a stock fuel oil furnace unit.The door has two peg hinges so it just lifts off and the electrical connection is just one plug for the control signal and a power cord for the primary power. The PLR controller uses the door draft fan control signal to activate the burner which is its own self contained system. Thats floor dry and used oil if you are wondering what's on the floor. I knocked my drip bucket over while working on it.

The pre heater assy. Originally the 1/8" steel pipe went all the way to the front where the nozzle holder fitting is. I cut out a section of the pipe then silver brazed it into one end and machined the nozzle holder down an silver brazed that in the other. It prevents leaks and further improves heat transfer from inlet to final nozzle outlet. It also has a silicon rubber impregnated fiberglass outer insulator jacket.

The burner end getting ready to light. You can see the light blue ignitor spark streaming out over the nozzle.

Typical used oil flame. This one is running at roughly 250K BTU.

Making smoke just for the sake of making it! This was a test burn of a old tire and all the assorted plastic from the bodies of two TVs and several computer monitors! I was using the shop air hose to force extra draft air through the system while the door was open. I think my calculated peak BTU transfer to the water jackets was around 1.5 million BTU's even with a stack temp around 1000 F while pushing at least 2000 CFM!

BTW I purposely designed it to handle that level of short term thermal abuse without problems.

Relating to control system logic the PLR is just concerned about seeing a certain temperature change within a specific time period once it starts a heating cycle so it really doesn't care what the heat itself comes from. If a positive temp change is not met within a certain time period it follows the solid fuel protocol of just assuming the fire went out and does the draft standby and eventual circulator pump shut down based on preset lower temp limits. Once the boiler temp goes below 100 F the pumps shut off and the backup heating for the house takes over.

Starting is rather simple. With solid fuels it's basically just light a fire then push the start button. The PLR keeps the intake draft systems on while it does a timing and temperature change cycle which expects the water temp to reach a certain level after a certain time period or it just assumes the fire went out and goes back into standby mode. With the used oil burner its just push the start button and walk away!