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Waste oil burner video

07-18-2009, 08:08 AM
I did another melt yesterday with the waste oil burner. I didn't get any oil leakage like last time but still got a lot of smoke around the tuere and the seams of the unit (three piece furnace, base, wall, and lid). If I lived in the country I would not worry about the smoke but being inside the city it is just too smoky to continue with this arrangement. I will be going back to propane, it's cleaner and easier to control.

07-18-2009, 01:45 PM

Thanks for the video, it helps me get an idea on how the burner performs. I hope you don't give up entirely on the oil type burner. The smoke is much less than I anticipated it would be.

Do you think it might still be a lean/rich thing or is that difficult to control because of the design? The smoke looked whitish in the video.

HerbD :cool:

07-18-2009, 03:20 PM
I did have some trouble with the oil mist control. Too much mist and it smokes around the seams and tuere. Apparently some oil condenses and gets pushed out by the higher air pressure in the chamber. Cutting the mist some reduces the smoke but then you don't get the heat needed to keep it burning well.
I am still considering a new furnace with only two parts, body and lid as opposed to my three part unit. That should help keep most of the oil inside.
From the vent, there is no smoke noticeable. It burns quite clean there.
I am going to propane for the time being, I'm afraid the neighbors will complain and I will be shut down.

07-18-2009, 03:56 PM
I don't want to beat a dead horse, but I hope you are able to figure it all out and get a clean burn.

Have you been able to exchange ideas with any of the people that are advocating the oil burners? Is what you are experiencing above normal as far as smoke etc? Do any of the oil guys claim to have "perfected" the burner to the point of no visible smoke?

I've yet to fire up my charcoal based furnace, waiting till I can bend (on the metal brake I'm welding) the transition piece from blower to air injector. Since I live in a city I'm concerned too about any smoke (I don't anticipate that it will smell like mesquite BBQ - LOL.)

I made my second ceramic crucible yesterday, just waiting for my daughter the ceramicist to get back from Chicago so she can fire it for me. I modified the mold to include a pouring spout on this second one that I've made. If it works in the furnace I plan on getting some powdered graphite and trying to make a graphite based clay crucible. Found the recipe for the clay in a book an making your own crucibles.

Last week I bought some angle iron and cut it into 8" pieces to make a set of ingot molds. Should be a good, non-critical welding project. Slow but steady progress.

Keep up the good work, always interested in how the projects are going.

HerbD 8)

Uncle Ed
07-18-2009, 08:47 PM
Hmm. Incomplete combustion? Would increasing the air flow OUT of the unit allow a better (and cleaner) burn without having to choke the oil? I would think the seam seepage is due to incomplete combustion of large droplets or back pressure in the vessel.

I can't tell if you are using any forced induction to atomize the fuel (though I seem to recall you welding up a squirrel cage housing).

07-19-2009, 01:37 AM
do you think a bigger exhaust vent could help? or a smaller burner nozzle + higher air pressure??? (random ideas, I'm no oil burning or furnace expert)

I expect a very fine mist/vapor is a good thing for the sake of better oxidization, and smoke is generally caused by incomplete combustion.
(edit, looks like Grebbler is thinking somewhat the same thing)

perhaps there is too much oil going in, and whatever is initially vaporized (or evaporates?) burns clean, and any excess oil smokes.

or it could be nasty dirty oil! :lol:

07-19-2009, 05:47 AM
HenryM and Grebbler,
You are probably right about the vent size. This furnace was made as an electric unit originally and the vent is only an inch in diameter. That causes higher pressure than it should be in the chamber forcing air (and any unburned oil) out the seams.
Most of the smoke is from oil that was forced out the seams early in the burn when the chamber hasn't reached a high enough temperature to burn completely.
I will try to open the vent but will be tough, this unit is about 15 years old and has been fired a lot. It's pretty hard at this point.
I'm also going to try to seal the unit better with furnace cement, if I can keep the vapors from seeping out that should solve the smoke issue.
By the way, the blower is going to be for a propane burner. I want both options working, the propane will most likely be used in the winter when I have to work inside. The oil burner uses compressed air at around 20 psi to spray the mist into the furnace.