Purging a Tank For Cutting/Welding

[Industrial Toys]

I have seen a thousand times the suggestion to put an exhaust hose in a tank for reducing risk of explosion.

Never ONCE did it say if Diesel or Gasoline Exhaust matters. Googled it, nothing!

I made the mistake of accepting this waste oil tank, years ago, Maybe 750 Gallons.

Now, I want to cut it in two with a plasma torch to use it to store some manure. No other use for it, nor will I probably ever have one.

I only have diesel exhaust. Tank has sludge in the bottom, I tried to remove, without much luck.

Tank has four, four inch bungs that are now open. Is that safety enough for it to stop from blowing up?

I'm thinking old engine oil often has gasoline mixed in with it. I have also had it fifteen years or so. Can vapours live that long? I mean, if it did, we shouldn't have all these STALE GAS issues.

Used a step drill to drill an almost 1" hole.



Tried heating sludge with a heater, with limited results.

 

[Captain Dirty]

My 200 year old house had a 275 gallon fuel oil tank that had been installed in the root cellar when some sill work was done; the tank had leaked, been condemned, and sat "empty" for years before I bought the house. I chose to cut it up and remove it. I used a cold chisel to cut an arc at the bottom of one end, bent the flap out, and used a broomstick with the lid of a tin can screwed to one end to rake the debris from the inside of the bottom. As I recall, it was rusty scale, no liquid or "sludge". Having only a Lincoln buzz box,, I cranked the amps up to 225 and cut the tank using 6011 rod soaked in water.

After I got bottles and a torch I have used oxygen-acetylene to cut the heads out of 55-gal oil drums after rinsing the drums and then filling them to within about 1/2" of the head with water.

No explosions or fire and I am alive to tell the tale.

You could test for an explosive mixture by putting the tank in a field and dropping a firecracker into it. You could do this in the next hour to celebrate your national holiday or wait till Saturday to celebrate ours.

 

[3Ts]

A carbon dioxide fire extinguisher discharged into the tank would purge any oxygen. Personally, I use water and a battery powered demolition saw. The water leaks out over the saw blade and keeps it cool and no sparks.

 

[Roadworthy]

It takes fuel, heat, and oxygen to have combustion. The idea behind running exhaust into the tank is to purge oxygen with the already burned fuel - air mixture. If you could prevent oxygen entry into the tank any fumes could not explode or even burn. Since that's not practical exhaust is an option - diesel or gasoline. Filling the tank with water is an option - water displaces any fumes. The carbon dioxide fill is also a good option, just remember it's heavier than air so keep any openings on the top side. Good luck with your project.

 

[Industrial Toys]

Thanks. It is CANADA day here, but I guess I missed it. And yes, I do happen to have a bunch of old huge CO2 extinguishers. I never even thought of that.

I may abandon the project altogether. I could not tell how much sludge was in the bottom. It may appear to be ten pails or so! Some of the worst stuff imaginable, like what California is always Warning everyone about!

I don't want to leave this thing around for someone else to have to clean up some day, but what am I supposed to do with the sludge? I can burn some on a brush pile, but not that much.

 

[Redlands Okie]

Our local sanitation has several days scattered through the year that is poorly advertised to bring in containers of hazardous materials such as engine oil, cleaners, etc that normally would not be accepted in a dumpster. Does your area do something similar that you could dispose buckets of crud?

 

[Egon]

Engine Exhaust gases Are not suitable for creating an inert atmosphere within an enclosed tank.

https://open.alberta.ca/dataset/e1b...b283-ebcc6412ea01/download/whs-pub-fex004.pdf

 

[Industrial Toys]

Thanks. I didn't specifically see anything mentioning using engine exhaust. Is it unacceptible practice because it is so undefined? How much is enough? What RPM, for how long?

I am still curious if it could blow up with four large bungs open?

We have hazardous waste collection days, but the depositry is far away and I am totally oblivious to local news and events as it's ALL Left oriented media in this country, so I don't listen or watch.

 

[JPRambo]

Any of the local parts stores or oil change places take use oil/sludge?

 

[Industrial Toys]

My Mechanic/Customer/Friends takes all my used oil for their waste oil furnace, but I doubt they want sludge. It's identical in texture and appearance to that roofing tar you buy in a can. If I had a castle, I could take it to the top of the towers, heat it up and pour on invaders. lol