Author Topic: overused / rancid veggy oil  (Read 6081 times)


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overused / rancid veggy oil
« on: November 22, 2008, 08:55:13 PM »
« Last Edit: December 26, 2009, 09:30:39 AM by jens »


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Re: overused / rancid veggy oil
« Reply #1 on: November 23, 2008, 12:05:21 AM »
Some of the oil I get has been over-used to the extent that it can not be converted to bio diesel.


I get some pretty rancid stuff that has always passed all the bio tests after its been processed. How do you get to know this stuff wont convert ?  What exactly happens to it ? Curious Jens,  not doubting you.  :-\



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Re: overused / rancid veggy oil
« Reply #2 on: November 23, 2008, 01:15:23 AM »
If a bio-diesel pro won't use it, you probably should not use it either.  But you saved him the trouble of disposing it.  Maybe you can use it for firewood lighter?


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Re: overused / rancid veggy oil
« Reply #3 on: November 23, 2008, 07:50:37 AM »
if it smells like paint thinner it may very well be contaminated with paint thinner!
i dont know about disposal issues there, but

around here if we have "any" thinner, brakefluid, chlorinated brake cleaner in a 55 gallon barell of waste oil
the drum becomes toxic waste and they charge 550 bucks to dispose of it!

so needless to say we don't allow anything in  our waste oil stream.

i don't know about waste veggie, but i bet the guy you got that jug from has similar epa concerns, or if you are in
canada the canadian epa probably gets bitchy about thinners and such,

anyway i would not burn it in my engine even if it would run fine, it might offgas some sort of carcinagen and cause cancer.
same goes for a fireplace fuel, maybe more concern there.

i say take it back to the dude you got it from

bob g
otherpower.com, microcogen.info, practicalmachinist.com
(useful forums), utterpower.com for all sorts of diy info


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Re: overused / rancid veggy oil
« Reply #4 on: December 05, 2008, 01:11:55 AM »
Last year a controversial document came out about polymerization of veggy oil and one of the signs is that it takes on a "paint thinner" smell. At that point it is not very good for use as WVO in a diesel engine. It can be caused by a few different things. Information on this document could be found at www.frybrid.com. That site also has lots of info on WVO conversions including some listeroids.
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