I realize this is an old thread, but I feel this might be insightful to anyone looking for WMO.

We get paid for waste oil although it's only $.27 / gallon. The disposal company wouldn't pay anything last year but they're losing waste due to recent competition so I guess they decided to pay up. We don't have a contract with the disposal company and I have given out waste oil to local shops using it for heat. I would be nervous giving it to an individual that I don't know. We're responsible, legally, for ensuring the oil is disposed of properly. If an individual picked up 25 gallons of oil in cubies and was hit on the way home, leading to a a spill, the state EPA could show up at our place asking questions. I have more important things to do than be involved in that and I don't want my company mentioned in a news article that might paint us as the evildoers behind all global warming.

Any company selling large amounts of oil is supposed to take in waste oil. Advance Auto, Autozone, and others have tanks for waste. People have to sign a sheet so there's a paper trail in case the oil is contaminated. Contamination includes chlorinated solvents, gasoline, diesel, paint thinners, soap/detergent, and other stuff. It's common to find people leaving bottles of oil outside the store when the store is closed so they don't have to sign the sheet. Quite often, the oil is not contaminated, it's just the people don't want to sign the sheet. The stores aren't supposed to mix in any oil they can't trace to the owner so what do they do with it? There's about 30 gallons of oil in quart and gallon jugs sitting outside the Advance Auto across from the shop here. I'm not afraid to open a bottle to see if it would be good base stock.

If you're looking for shops to supply it, you've got a mixed bag to consider. Small shops, the informal places that operate in a 2 bay old garage of an alley and have a hand painted sign might let you put a drum out to collect oil. It's a matter of convenience as they have to bring the oil to a larger place for disposal. But you're likely to end up with all sorts of garbage in your oil. Anti-freeze, brake fluid, brake cleaner, gasoline, and anything else might end up there. Yuck.

The the large shop for the most part doesn't care as much about what's in the tank as the big collection company takes care of it. Motor flush chemicals, brake fluid, solvents, and antifreeze can all get into the big tank. Settling gets rid of some of it, and the right cleaning process can evaporate more. If you can take oil off the top and then clean it right you'll probably be ok but there's no guarantee that the only thing you're burning is oil.

The most consistent clean oil I've found is from individuals. You know, the guys who change oil religiously at X number of miles, always use the same brand, always have a nice, clean drain pan in the garage. They'll even make sure they put it into an oil jug to return it to the store. If you can find those guys you'll get a nice source of oil that requires little clean up before burning. And if you're lucky they'll even bring it to you. It may take time to build up that network but it's a good one to have if you can do it.

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