Lister Engine Forum

Alternative fuels => Waste Motor Oil => Topic started by: phaedrus on July 03, 2007, 08:53:38 PM

Title: removing contamination-carbon
Post by: phaedrus on July 03, 2007, 08:53:38 PM
I've read in various places on this site about people trying to remove carbon from waste lube oil. The carbon particles are very small, and the oils are designed to keep the carbon in suspension - two serious problems. In addition, waste oil often contain contaminates that are liquid - no filter can remove these very well. So I've been thinking about the problem as a chemistry problem, not a mechanical one.

Here's a short paper for a lay audience on contamination:

You'll see in that article that it's possible to precipitate out the soot and additatives - and clog the engine oiling system!

From the hip, as it were, and based on that article in part, it looks to me like the way to remove the glycols, acids, additative "package" and the suspended carbon, is to make up a solution of 1% sulphuric acid in water and mix that about 1 or 2 parts acid-water to 10 parts used oil - mixing very violently, so as to form an milky emusion. Then allow that to slowly settle out, draining away the watery fraction. I'd run the mix through a rotary pump to mix 'em. After settling and separating the oil faction it would be filtered to 1 or 2 microns and diluted to a reasonable viscosity for fuel. The watery faction would be evaporated in an open pan and the solids disposed of in newspaper in the normal house-hold trash stream.

I am not recommending this - I am offering it for comment.
Title: Re: removing contamination-carbon
Post by: Dail R H on July 04, 2007, 11:30:56 PM
   You mean 1 part acid  in 99 parts water right? I just happen to got some sulfuric acid on the job I'm working now that needs disposed. Think I'll try.
Title: Re: removing contamination-carbon
Post by: phaedrus on July 05, 2007, 03:19:59 AM
Caution!  I put this up for comment - not as a recipie!  Actually I don't think that the acid concentration matters much, but I have not tried this idea out - it's just an idea. Be careful doing 'speriments.
Title: Re: removing contamination-carbon
Post by: phaedrus on July 06, 2007, 02:12:57 PM
The government of oz has a descriptive story about oil-re-refining

Obviously they are able to remove the carbon.

Title: Re: removing contamination-carbon
Post by: Doug on July 08, 2007, 03:05:58 AM
We got carbon out as well as tar with Hydrazine and big centrifuge......
Title: Re: removing contamination-carbon
Post by: phaedrus on July 08, 2007, 05:29:24 PM
Doug, I can understand the centrifuge working because of the densities, but I don'tunderstand the use of hydrazine in your process. H2SO4, though of course not without cautionary risks, looks both easier to get and safer to handle than hydrazine. (I wouldn't know where to begin to get hydrazine.) 

Can you tell me about your process?


Title: Re: removing contamination-carbon
Post by: Doug on July 09, 2007, 02:05:41 AM
The process was fairly simply awful waste oil went into a pair pf small high temp low presure cracking pots.

Awful things happend in the pots resulting in cracked ends, tars light ends/condensate and coke/ash cake.

Cooled and mixed with hydrazine before spinning in the big centrifuge. Some sort of reaction caused but the hydrazine made things drop. Tars and solids would spin out as an evil black sludge. Light brown vile smelling fuel oil came out for use as industrial burner oil and fleet use ( although we were probably not suposed to drive trucks on our own fuel ).

"Man alive.... there are men alive scraping ash cake from inside the 520 !!!!!"
One of my smart comments.

Bayer chemical ( ya we bought it from the asperin people isn't life funny )can provide you with hydrazine in 45 gallon drums.....
They also have drums of pills and drums solvents and of all kinds of wierd and wonderful stuff from farming, industrial and medical use to choose from same company and same place. They won't let you have a drum full of heart pills don't ask.

Not at all sure if I should laugh or be terrified how easily one can buy large quanties or realy nastey chemicals. And the kinds of chemicals one could use for all kinds of scary things.

Title: Re: removing contamination-carbon
Post by: phaedrus on July 09, 2007, 03:06:17 PM
Thanks, Doug

Yes, the possibility of dangerous bad behavior is real - for an example

Thanks for the run-down - I have no formal education in chemical engineering, but have read on the subject over many years, leaving me with a spotty understanding and no lab skills. I'll think on the hydrazine reaction until I understand it.

It is probably obvious, but the business with bad behavior, the risks, seem to vary with, well, bad behavior by so-called "leaders". eg if a country invades another and blows up people and their houses and kills kids and old people, well, it pisses people off, and a few of these people sometime then do mean things. Best to be nice, share, and get along...

wiki says this about hydrazine:  " Hydrazine is highly toxic and dangerously unstable, especially in the anhydrous form. Symptoms of acute (short-term) exposure to high levels of hydrazine may include irritation of the eyes, nose, and throat, dizziness, headache, nausea, pulmonary edema, seizures, and coma in humans. Acute exposure can also damage the liver, kidneys, and central nervous system in humans. The liquid is corrosive and may produce dermatitis from skin contact in humans and animals. Effects to the lungs, liver, spleen, and thyroid have been reported in animals chronically (long-term) exposed to hydrazine via inhalation. Increased incidences of lung, nasal cavity, and liver tumors have been observed in rodents exposed to hydrazine."

At some point I expect I may do some very small scale 'speriments with dirty lube oil, test tube size stuff. Getting the glycols and the suspended carbon to move over into a watery phase can't be that hard to do safely. Then a few cycles through a nice filter and dillution to fuel suitable for a listeroid.
Title: Re: removing contamination-carbon
Post by: Dail R H on July 09, 2007, 11:53:37 PM
   I brought my acid home,about 5 quarts in 3 seperate bottles.Experiments to follow.
Title: Re: removing contamination-carbon
Post by: phaedrus on July 10, 2007, 02:29:59 AM
Dale, Please forgive me, but I worry - please be very careful to be safe.   P    from wiki:

"Although sulfuric acid is non-flammable, contact with metals in the event of a spillage can lead to the liberation of hydrogen gas. The dispersal of acid aerosols and gaseous sulfur dioxide is an additional hazard of fires involving sulfuric acid. Water should not be used as the extinguishing agent because of the risk of further dispersal of aerosols: carbon dioxide is preferred where possible.

Sulfuric acid is not considered toxic besides its obvious corrosive hazard, and the main occupational risks are skin contact leading to burns (see above) and the inhalation of aerosols. Exposure to aerosols at high concentrations leads to immediate and severe irritation of the eyes, respiratory tract and mucous membranes: this ceases rapidly after exposure, although there is a risk of subsequent pulmonary edema if tissue damage has been more severe. At lower concentrations, the most commonly reported symptom of chronic exposure to sulfuric acid aerosols is erosion of the teeth, found in virtually all studies: indications of possible chronic damage to the respiratory tract are inconclusive as of 1997. In the United States, the permissible exposure limit (PEL) for sulfuric acid is fixed at 1 mg/m3: limits in other countries are similar. Interestingly there have been reports of sulfuric acid ingestion leading to vitamin B12 deficiency with subacute combined degeneration. The spinal cord is most often affected in such cases, but the optic nerves may show demyelination, loss of axons and gliosis.

International commerce of sulfuric acid is controlled under the United Nations Convention Against Illicit Traffic in Narcotic Drugs and Psychotropic Substances, 1988, which lists sulfuric acid under Table II of the convention as a chemical frequently used in the illicit manufacture of narcotic drugs or psychotropic substances.[4]

In the United States of America, sulfuric acid is included in List II of the list of essential or precursor chemicals established pursuant to the Chemical Diversion and Trafficking Act. Accordingly, transactions of sulfuric acid—such as sales, transfers, exports from and imports to the United States—are subject to regulation and monitoring by the Drug Enforcement Administration.[5][6][7] "

Title: Re: removing contamination-carbon
Post by: adhall on July 10, 2007, 01:31:11 PM

Please excuse me, as well, for piping up with a warning of my own.

If you find the need to dilute this acid, be sure to add the acid (slowly) to the water and not the other other way around. Heat is generated when the acid mixes with the water, so proceed cautiously to keep things under control.

Once again, my apologies if this warning is unneccessary.

Best regards,
Andy Hall
Title: Re: removing contamination-carbon
Post by: cold comfort farm on May 25, 2008, 06:12:05 PM
is there any update on this thread.  I hope Dail R H is OK he has not posted since!

Title: Re: removing contamination-carbon
Post by: cold comfort farm on May 27, 2008, 07:00:09 PM
Thanks Cognos,
Does anyone other than rbodell  just settle, filter the oil to 1 micron then run it in a Lister. 
Sticking a couple of large Neo magnets in the filter will pull some of the metal out (maybe) not non ferrous though.

There is much more WMO out there than Veg and if there is a safe way to remove the nasties from the exhaust gases say maybe use a cat? Then it’s a much better way to go.  We can put the veg in the car and provide electricity with the WMO

Just my 2p worth or 2c
Title: Re: removing contamination-carbon
Post by: oliver90owner on May 27, 2008, 09:15:14 PM
cold comfort farm,

Not sure what nasties you ae referring to.

A cat converts NOx, CO and hydrocabons to harmless gases.  If there are heavy metals in the fuel in any appreciable quantities, these would soon poison the catalyst substrate.  Not sure how well they like soot as a feedstock.

I was intrigued by the (unwanted) addition of glycol (antifreeze) to counter the dispersant effects (act as a flocculant) in the oil and allow (or cause) the suspended (colloidal) matter to agglomerate, but not sure whether the particles would then spin out in a centrifuge.  Should do, is my thought on it but I may be wrong.....Might be worth someone trying it on a small batch.

Regards, RAB
Title: Re: removing contamination-carbon
Post by: cold comfort farm on May 28, 2008, 07:22:34 AM
RAB, List
I was meaning the heavy metals etc.
If the particles are smaller than 1 micron would they cause any harm to the engine anyway.  Even if you have to do a rebuild every year, for me it would still be cost effective.  We pay about £100 per month on electric (its a farm not house) so the savings would be good for us.  Everything we have, where possible, is low energy. 

Oliver, could you expand on your glycol experiment please qty etc. your best guess would be fine.

Its nice to see and hear that people are willing to try and experiment on this forum rather than just tell you not to do it or go look for the answers that’s been posted 5 years ago.  When we have worked this one out we can start on what to do with the tyre mountain.  lol

Title: Re: removing contamination-carbon
Post by: oliver90owner on May 28, 2008, 08:58:53 AM
cold comfort farm,

Hi, where are you?  I am in Lincolnshire.  BTW, I am not Oliver - I just own a 90 (and about a dozen other Olivers)

I just read the link at the top of this thread (the part re glycol, and the way it leads to engine failure).  Wondered how good it might be as a flocculant in this application. 

Link says as little as 0.4% coolant contamination, so presumably 0.2% shoud be enough to do something, given time.  i would think1% and lower might give an indication of likely assistance in coagulating the solids.  It might just make a mess, like it does of the engine!  It might need heat to speed up the effects. 

It was just that the mode of engine failure seemed to indicate some possibilities for cleaning up used engine oil - as long as all the glycol is removed if anyone thinks it looks good enough to use again as a lubricant!  There are, of course, other similar compounds to ethylene glycol that might work as well, or better, and not be harmful.  It might be a way of using up old antifreeze as well as old oil!!!

Regards, RAB
Title: Re: removing contamination-carbon
Post by: cold comfort farm on May 28, 2008, 10:02:37 AM
Sorry I was being idle on typing your post name "Oliver90owner"  lol.

I am in Misty Derbyshire. I have a Lister CS 3hp and a Lister Petter genset (when I pick it up on friday)

I will put some old oil in a jam jar a bit of glycol and give it a good shake then leave it a month or two see what happens.  As a control I will just sit another jam jar full of untreated oil next to it.

If it cleans then I will look at the next stage of seeing what comes out the exhaust.  My freindly garrage will put  it on his emmisions meter.  We may as well gat true facts and figures rather than say dont do it. It becomes an informed choice then.

Title: Re: removing contamination-carbon
Post by: Quinnf on May 28, 2008, 04:25:52 PM
Why not just use baking soda (sodium bicarbonate) in the water wash and capture both the acidic and caustic components at the same time.  A handful to a gallon of water or so should be plenty.  You're performing a simple extraction of anything hydrophilic into a buffer.  Settle out the bicarbonate wash, then water wash to remove any residual bicarbonate and check the pH of the wash water to make sure the bicarbonate is completely removed.  At the worst, you'd expose your oil to a pH of around 8.0 instead of the pH extremes that acid and caustic washing would entail. 

Title: Re: removing contamination-carbon
Post by: rcavictim on May 29, 2008, 11:37:46 PM
I read all this with a bit of agony.  Wouldn't you end up with more free time if you worked for minimum wage and used the money to buy store bought diesel at $6/gal?

I've got waste oil with water and other junk in it here gravity settling.  This process takes years.  I cannot imagine adding water to it now and re-agitating it.  It would be several years again before I could use it.  Life is too short and 'spare time' is WAY too precious to waste.
Title: Re: removing contamination-carbon
Post by: blacksea7 on June 23, 2008, 11:00:19 PM
If you're really into doing this, do what the oil industry has been doing for aeons... A centrifuge spun by the engine... works very, very well and it's nearly fool proof! You have no clue how much oil has been pumped out of the ground using crude or waste oil run through a centrifuge without any ill effects. I'd be very skeptical about running any form of acid through the injection hardware as eventual scarring could happen whereas, if you run the fuel through a centrifuge (clay is also an incredible fuel cleaner and polisher) everything you don't want going through the engine is discarded.
Title: Re: removing contamination-carbon
Post by: SHIPCHIEF on November 26, 2010, 04:17:45 PM
I picked up a pair of 275 gallon home heating oil tanks fom a local biodiesel maker. He picked up used fry cook oil from the local restaurants, and made biodiesel in his garage. He had a very well thought out operation and ran his final biodiesel product thru toilet paper filters using a small gear pump. He used Motorguard filter canisters that hold a toilet paper roll. I found them marketed for auto painters, to final clean the compressed air before it passes thru the paint gun. Same unit they used to sell for motor oil, sometimes the pipe fitting size is larger for air service.
Anyway, he triple filtered his new fuel to remove the glycirine and lye drop out, and was happy with it.
My plan is to dillute my WMO with diesel, then run it thru the filter a few times to see what happens. The cellulose (toilet paper) will absorbe quite a lot of water, and filter down to 1 micron. That should render it safe for the engine?