Micro CoGen.

Fuels/alternatives => Bio-Diesel => Topic started by: Jens on April 16, 2010, 10:27:30 PM

Title: Polymerization and the effect of blending on it
Post by: Jens on April 16, 2010, 10:27:30 PM
This just popped in my head and I thought I would bring it up here. As you guys may know, I have issues with veggy oil polymerization products clogging up my injection pumps.
I wonder what the level of polymerization is in blended fuels. More specifically, is it a linear relationship of blending ratios or are there other factors to consider.

Here is an interesting (I think so anyway) thought ..... the problems I am having are arguably caused by a slight leakage of veggy oil into the lower injector pump cavity which then turns to goo because I run my engine in a very hot environment (sound enclosure). Now let's say that I mix in 10% WMO to the veggy oil I am using for fuel. The leakage in the injector pump is still the same so now there is a combination of veggy oil and motor oil in the lower IP area. Since motor oil doesn't polymerize, I am wondering if small amounts of motor oil would prevent the formation of goo from the veggy oil. Would the small bits of motor oil distributed throughout the veggy oil prevent the veggy polymerization product from forming a goo ? In effect seperate the globules of goo with a slippery oil layer ?  Would we end up with polymerization products 'lubricated' by motor oil that in effect doesn't form a solid goo-like mass and allows this waste product to drain ?

Thoughts, opinions, have you tried it ?
Title: Re: Polymerization and the effect of blending on it
Post by: bschwartz on April 16, 2010, 10:42:24 PM
That sounds reasonable.  I have not had 'problems' with the poly build up clogging things yet, but it is clearly there on the shaft of my IP.  I drizzle motor oil on the exposed parts of the IP and it seems to do exactly what you are hoping for.  I still get the buildup, but is seems to be a gooey consistency instead of the rubbery plastic that forms everywhere else in my shop  ;D
Title: Re: Polymerization and the effect of blending on it
Post by: veggie on April 17, 2010, 10:45:10 AM
Sounds like it might work.
Mix some in a glass milk bottle and let it sit for a few days.
See if there is any reaction or separation.
Perhaps oils that are made for mixing such a 2 stroke oil might blend even better.?

veggie
Title: Re: Polymerization and the effect of blending on it
Post by: cognos on April 17, 2010, 12:38:16 PM
Polymerization can be initiated by exposure to oxygen - air or water. Usually, an anti-polymerant is an oxygen scavenger - like BHT - butylated hydroxy-toluene. It can also be initiated by an alcohol, basically any contaminant with an "OH" in it, written in the trade as ROH - where R is any radical.

So - limit exposure to air or water, and contaminants. Once the oil has been exposed, the "seed" for future polymerization has already been sown, even if you remove the air, water, or other contaminant.

Polymerization will occur at a higher rate at higher temperatures. So... not really practical here. Your engine environment is what it is.

Waste motor oil contains leftover additives which *may* slow down "polymerization" - if, in fact, that's what's happening, as opposed to gum and "varnish" formation. But the additive *may* help with that, too.

The dispersant additive may help with keeping "gunk" in suspension.

Try 3 containers - one raw WVO, one a mix of WVO and WMO, and one a mix of WVO and NEW Motor Oil - anything cheap. I'd lay odds on which mixture perfoms best at not separating or forming "gunk"... and a little additive goes a loooong way...

Title: Re: Polymerization and the effect of blending on it
Post by: cognos on April 17, 2010, 06:02:55 PM
That's a very good question. I don't have a definitive, first-hand answer at this time. I'll ask around.

All I can say is that products are tested for their propensity to contain or form gums and varnishes, and they are also tested as to the conditions under which polymers will form. Two (or more) separate tests.

Oils are "degummed" in a process at the lubestock plant. Can "Gums and varnishes" exist without polymerization? Good question. When I think about it, it probably means that gums are just soft polymers, and varnishes are brittle polymers. But I don't know. I just know we do everything we can to remove them or stop their formation.

All bets are off with mystery fuels - like WVO... ;D but I'd wager the same chemical processes regarding polymerization apply - O2 + Temperature.
Title: Re: Polymerization and the effect of blending on it
Post by: Tom Reed on April 18, 2010, 05:50:08 PM
I oiled the rack on my IP regularly and there was still a major polymerization build up on the rack. However the Marvel Mystery oil cut right through it last fall and and the rack is still very free 225 hours of runtime later. I have now been using wvo during that time. Just a mix of pump diesel, who and wmo.
Title: Re: Polymerization and the effect of blending on it
Post by: vdubnut62 on April 18, 2010, 09:38:32 PM
Quote from: Tom on April 18, 2010, 05:50:08 PM
I oiled the rack on my IP regularly and there was still a major polymerization build up on the rack. However the Marvel Mystery oil cut right through it last fall and and the rack is still very free 225 hours of runtime later. I have now been using wvo during that time. Just a mix of pump diesel, who and wmo.

Umm.. "who"??
I know, it should be obvious, I seem to be very slow today.
Title: Re: Polymerization and the effect of blending on it
Post by: mobile_bob on April 19, 2010, 02:40:58 AM
who = waste heating oil ?  maybe?

bob g
Title: Re: Polymerization and the effect of blending on it
Post by: akghound on April 19, 2010, 10:28:17 AM
Polymerization is caused by many things. Using copper or mild steel in the fuel system adds to it as well as moisture in the air. For a detailed explanation on this refer to the below link which will lead you to a 21 page document about it.
http://www.frybrid.com/forum/attachment.php?attachmentid=1491&d=1167782933 (http://www.frybrid.com/forum/attachment.php?attachmentid=1491&d=1167782933)
Ken Gardner


Title: Re: Polymerization and the effect of blending on it
Post by: mike90045 on April 19, 2010, 12:08:01 PM
Quote from: Jens on April 17, 2010, 12:21:30 PM
I do not wish to 'purchase' additive if I can avoid it. This is why I was thinking waste motor oil.
I think what I will try is to put two glass jars into the engine enclosure (probably needs to wait for next season though). One will have pure veggy oil and the other will be a mix of veggy and WMO. It might take a month or two to see any results but that should tell me if the concept has any merit at all.

Mix and cycle it a few times, from the fridge to sauna, and see if it separates out or anything.
Title: Re: Polymerization and the effect of blending on it
Post by: TimSR2 on April 19, 2010, 02:08:06 PM
Just a thought regarding Automatic Transmission Fluid. In the 80's I  worked on cars both as a hobby and for a living. I spent years on the wrenches.  It was a time worn tradition to throw a quart of Dexron into the motor oil of a badly gummed up engine to release all the crud buildup that had deposited inside. I have done it many times, on engines that were to come out for rebuild soon, on used cars that were gumped up from neglect and short trip driving, or just as a flush for maintenance.

The drill went like this: Change the oil and refill it short a quart, put in a quart of Dexron and drive 1000 miles and drain. Oil always came out BLACK.  On a really neglected gasoline engine I will put a gallon of diesel into the tank to unstick the piston rings too. ATF and Diesel fuel are the best solvents I know of.

Jens, if I had your problems I would try this without hesitation. I'd put some diesel or ATF into the fuel  just to be thorough. Or maybe both!
Title: Re: Polymerization and the effect of blending on it
Post by: mobile_bob on April 19, 2010, 04:41:59 PM
i will second that motion

atf seems to work very well at breaking down sludge/gums/varnish and other crapola in the crankcase,
it might even work well mixed in with veggie to keep the polymerization from taking place?

seems plausible.

bob g
Title: Re: Polymerization and the effect of blending on it
Post by: akghound on April 20, 2010, 11:09:26 AM
Cut and copied from http://www.frybrid.com/forum/showthread.php?t=15358 (http://www.frybrid.com/forum/showthread.php?t=15358) where you can find info on a product to help prevent polymerization.

By Chris Goodwin
Back in 2005 no one really knew why we could filter vegetable oil to 2 microns and a month later plug a 10 micron filter, we were not sure why vegetable oil and biodiesel both caused the formation of deposits on the steel surfaces of the fuel system, no one knew what it was or why it was occurring.

A year later Joe Beatty released "The Beatty Report", his findings created quite a stir and have subsequently been supported by a great deal of research. Some in the SVO field swore that metals were not reactive, that without water in the fuel this could not happen and went so far as to attack Mr. Beatty himself. Subsequent research has come to light showing that every statement he made was completely accurate and thanks to his work we all learned a great deal about how and why vegetable polymerizes.

In short, vegetable oil breaks down through a process known as oxidative polymerization, oxygen attacks the double bonds of the triglyceride molecule and begins to break apart and twist the molecule until it can form long chain polymers with other molecules and it is these polymers that eventually link together forming a coating on particular metals and/or filter media. The formation of these polymers on the filter plugs it, the formation of polymers on steel interferes with tolerance critical parts in the injection pump and injectors can cause moving parts to seize or break and can accelerate the formation of rust on those parts.

All vegetable oil will polymerize, the less saturated the oil the faster it will polymerize. New vegetable oils are high in natural antioxidants which preserve them, however as the oil is used these antioxidants are used up leaving the oil unprotected. In the first stages of oxidation the molecule begin to degrade and peroxides are formed, these peroxides give food cooked in the oil a bitter or off flavor and the restaurant disposes on of oil, so by the time we get it the oil has already begun to oxidize, in addition it is full of contaminants; water, salts and acids from the food that was cooked in it, all these things contribute to further degrade the oil. Certain other factors accelerate polymerization; exposure to oxygen, exposure to heat, exposure to reactive metals and exposure to sunlight. Limiting any or all of these will radically extend the life of your oil.

Ken Gardner
Title: Re: Polymerization and the effect of blending on it
Post by: cognos on April 20, 2010, 03:04:45 PM
Sounds like what the lab guys said. 'Cept they said it with bigger words that I didn't fully understand... ;D

And ya, they are of the opinion that gums and varnishes are most likely some form of polymer.

One of the catalysts we use to cause polymerization of plastics is hydrogen peroxide. Peroxides are powerful polymer catalysts. As are some metals.
Title: Re: Polymerization and the effect of blending on it
Post by: Tom Reed on April 20, 2010, 09:01:21 PM
Quote from: vdubnut62 on April 18, 2010, 09:38:32 PM
Quote from: Tom on April 18, 2010, 05:50:08 PM
I oiled the rack on my IP regularly and there was still a major polymerization build up on the rack. However the Marvel Mystery oil cut right through it last fall and and the rack is still very free 225 hours of runtime later. I have now been using wvo during that time. Just a mix of pump diesel, who and wmo.

Umm.. "who"??
I know, it should be obvious, I seem to be very slow today.

Sorry Waste Hydraulic Oil.  ;D
Title: Re: Polymerization and the effect of blending on it
Post by: vdubnut62 on April 20, 2010, 10:00:16 PM
Oh, of course! Duh!! ::)
Ron
Title: Re: Polymerization and the effect of blending on it
Post by: Dualfuel on April 15, 2013, 01:52:11 PM
Hi,
I really like this thread and learned a bit more.... I also got this when I started to write...


Warning: this topic has not been posted in for at least 120 days.
Unless you're sure you want to reply, please consider starting a new topic.

Sorry if I am breaking a taboo but things haven't changed and the info is still good!

I just wanted to add this thought...Oil based paint uses Linseed Oil which is a triglyceride the same as soybean oil. So if you are looking for something that will stop polymerization, and is readily available, try thinking of your fuel as if it were paint, and you wanted to stop it from drying rapidly...
turpentine slows the hardening of paint, so does gasoline. Having the can full and the lid tight slows it too.
I wash my BD in snow and rain water, removing all the soap and methanol, after this the polymerization slows to a standstill. Go to the infopop biodiesel list and read about what Tim C. Cook does with his SVO to treat it...something about Baking Soda...

Anyhow, BPJ