Will this concept work? I plan on using waste oil, rotary drum pump, 1/2" tubing, and a brass mister head, along with a conventional propane burner Venturi body.

My limited experience suggests you will need additional forced air.  I used compressed air to mist the used oil through a DIY siphon nozzle and even at 60 psi through a MIG tip (.030 IIRC) it still did not provide enough draw to provide the needed air for good combustion.  I'm far from an expert in this field so take that for what it's worth.

Find an oil boiler burner and come up with a good filter system and use it a long way from anything you don't want to burn down.

Frosty The Lucky.

26 minutes ago, Frosty said:

Find an oil boiler burner and come up with a good filter system and use it a long way from anything you don't want to burn down.

Frosty The Lucky.

Would the attached diagram work do you think, or do I need forced air like Buzzkill suggested above?

I know that gasoline blowtorches use a similar system, the question really is whether oil is too thick or not flammable enough, or if a rotary drum pump would provide enough pressure.

I'm not the person to ask. I have a BAD opinion of home made oil burners no matter how many guys swear they're the best thing since sliced pepperoni.

I have no other opinion to express.

Frosty The Lucky.

Im thinking it wouldnt work (maybe with a few mods like having a copper coil around your nozzle before the jet ).... based on what little i understand you need the oil to be preheated and have a blower.... but ive never made or seen one in person so thats my 2 cents which is worth dirt

There are several posts on using waste oil on the site.

Old motor oil contains so much hazardous material it is considered dangerous to use as fuel.

The question is WHAT TYPE of waste oil? And how much of it do you have on hand?

 

Frosty is correct in that you MUST be present at ALL times when using one of these things. Also breathing the  exhaust fumes, even in small quantities, is not a good thing.

 

You may want to read the following materials.

http://www.michigan.gov/documents/deq/deq-ess-p2tas-burningusedoil_190423_7.pdf

https://www3.epa.gov/ttn/catc/dir1/w_oilacr.pdf

The results of the used oil sample testing revealed higher levels of several contaminants over levels found in No. 2 home heating fuel oil, including barium, cadmium, chromium, lead, zinc, ash and halogens such as chlorine and bromine.

http://www.nytimes.com/1985/11/09/us/epa-restricting-use-of-waste-oil-as-fuel.html

You may have to deal with the Environmental Protection Agency and several other government agencies if they find out you are burning waste oil. Transportation of waste oil is another can of worms to deal with. Most of this refers to store bought and installed oil burners, so you can imagine want they would do with a DYI project.