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

 

[Redlands Okie]

The four open bungs in themselves are not a for sure means of ventilating out any flammable gases I suspect.

 

[Industrial Toys]

No, I was just wondering if it constituted enough of an opening to vent an explosion without ripping the tank apart. So I get more of a woosh and not a boom!

 

[Topzide]

I've been around several oil/propane tanks that were purged with exhaust from truck. Just let idled for about 15 minutes on a 275 gal tank. I've personally done a 100 lb propane tank that way, and I'm still here! Thing I did differently was while exhaust was still going in, I moved a lite fireplace match to see if fumes would ignite. Main thing is be careful. Idea of CO2 fire extinguisher or if you mig, what about shielding gas to purge tank?

 

[Captain Dirty]

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.

Your good intentions are commendable. Could you pave the road to H*** with the stuff? How about cutting a hand-hole large enough to extract a sample to see whether and how obnoxiously it will burn.
Surreptitious burning may be the "best" practicable method of disposal.

 

[Industrial Toys]

It would help to have someone discharge the C02. There is no one else here at the moment, and would I really want to endanger someone else? Thinking about later this afternoon when it's cooler.

I wish, their was a junk part of the tank, I could just cut a quick big hole to settle my nerves.

Seriously, if it was just for needing the tank to store some manure, I would forget this, and just dump some on the ground. But this toxic mess needs to be addressed, sooner or later.

Thre is a name on it. I should call them and say I found this in the local stream and the fish and game people would like to have a word with them.lol Or they could just come and pick it up please.

 

[Captain Dirty]

I want to cut it in two with a plasma torch . . .

If you have a plasma torch you likely have the means to repair any hole/panel you make.

HOWEVER If the plasma uses compressed air to blow the plasma away you would be replacing the O2 you had worked to remove.

 

[Industrial Toys]

Placed the tank into position away from buildings, in the hot sun. I don't like it! Smells too fresh inside. Nothing like old oil or stale gas. And it's been here fifteen or so years. I would swear there was/is tar in there. It's not impossible that I wasn't given the correct information about old oil storage. Maybe I made some assumptions too.

So how dangerous is tar?

I'd like to say funny, but this is one of the first things I came accross.

THE EXPLOSIVE DANGER OF THE ASPHALT FUMES – A REMINDER AFTER THE ASPHALT TANK EXPLOSION AT LA CROSSE, WISCONSIN - Metropolitan Engineering Consulting and Forensics

Now, I'm really spooked! The prospect of not just being blown up but tar and feathered too.

Sitting here wondering what to do? It would be a stupid way to die.

I wonder if a sawzall would be better? I mean, you can't beat the ignition capabilty of a plasma torch. Possibly the worst tool, next to a torch.

 

[Industrial Toys]

Sounds lame, but I think I might try a jig saw.

Material appears to be about 3/16" steel. Got about 1/2" with a jig saw using a brand new WALTER blade, and figured that wasn't going to cut it, no pun intended.

Wouldn't 3/16" make a fine bomb though! lol


I noticed that the bungs appear to be five inch, but have nylon bushings to bring that down to four inch. Is that so the bungs don't rust in or is that plastic supposed to melt in a fire allowing the contents to boil off?

 

[MossRoad]

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.

You seem internet savvy, so why don't you just look up hazardous waste collection in your area rather than relying on a public service announcement to happen to coincide with a time you just might be watching wheel of fortune?

 

[Industrial Toys]

Spoke with a friend that has been repairing other peoples stuff in this rural/farm environment for fifty years. Says if it didn't have gas in it, just take the plasma torch to it. I stuck the leaf blower in there for a moment, discharged the CO 2 extinguisher a little and put the torch to it. I really didn't know if I was experiencing my last few seconds on earth! Well I got it cut in two and I'm still here. Thanks all for input.

Worst part was the paint (no doubt lead based) and labels I had to cut through. Leather gloves caught on fire and so wrapped glove in water soaked rag, which also quickly caught fire too from the intense heat.

More pictures to follow.

Now another problem. I was going to weld feet onto the bung plugs and make a fire in the top portion to get rid of any residual oil. But those nylon bushings in the bung holes will melt!