Does a propane tank absorb propane?

[Jstpssng]

I watched a guy trying to cut the top out of a 45 gallon barrel one time he was told to put an air nozzle in it and use an air chisel. He used the torch, It popped and flipped the top. He was a waist of skin but never got hurt.
I agree remove the valve, I like to leave it sit in the sun for a while then vent it continually, while working on it.
I also use propane bottles as air reservoirs, My compressor is about 50 ft from the work areas I have the 30 lb tanks hanging up side down with a drain pipe about 6 inches long hanging down and a manifold with a two couplings in it one large and one small. It gives you that little extra kick , as well as volume

I used a 30 lb taqnk for years, but somebody here mentioned that they aren't coated inside so may rust through. Chicken that I am, I sent it to the scrap pile.

 

[Johnp33]

It is mounted up-side down and I live at the 2000ft level in near desert conditions.
I have two air reservoirs before it gets to that one with drains. But It is not a bad idea, I will take them off in the spring put in some Tremclad paint, swish it around and let them dry in the sun. :thumbsup:Always willing to go that extra mile to be safe.

 

[Mark @ Everlast]

Propane is a volatile gas. It doesn't stick around. It can lay around, hanging low to the ground or in the tank, but when the pressure is gone, it does NOT stay liquid. This pore business may be true of some liquid gas that does not volatize. But I think even that may be attributed to little or no prep.

But there are several places you can find on the internet, even from the gas companies that discuss the nature of propane. The smell is entirely separate and over time, it will leave a sticky, oily film in the bottom of the tank...which can cause a flammability issue possibly, but its more likely to stink than anything else. If you completely fill up the tank with water, and possibly a little soap and flush it until all the bubbles purge, then let it sit for a day or so. When its dumped out and dry the propane has to be gone. The filling it up completely will force out any residual fumes of propane. The smell will hang around...but again its an additive to propane that has settled out, not propane itself.

 

[Egon]

Propane may come down the line with a few more addatives than Merkpatan. Things like water and H2S are pretty common in propane. Starts a little corrosion. Can lead to more with encapulations. The corrosion can be of a size you can't see with the naked eye and will be occuring between the grain boundaries. Gives the liquids a place to go hide.

On larger vessels, as pointed out by a few welders this could make for interesting events.

On a small vessel like a 20# C3 tank filling with water and boiling followed by air purge and a combustible gas tester should suffice.

Some fellows have commented on hot work on an emptyhydrocarbon barrel. there will be more than one fellow who's had the barrel blow up :

Chilled liquid propane can stick around for some time. As it is heavier than air when it evaporates it it has a tendecy to flow to natural ground traps and form a pool of vapour. Wind will disperse this vapour depending on how srong it is and what the local conditions are.

And Yeh, you never know what pollutants in C3 may be and they can be there.

 

[Johnp33]

My neighbour is looking for the 8 ft long tanks about 3 or 4 ft around he cuts them in half welds on a cutting edge and one end out making a good snow plow. Bigger ones he cuts into three sections, unless you have a machine that will handle it.
He is looking for one for me and I will remove the bucket on My Furukawa loader and mount it. Everything can be recycled, I do not know how he prepares it for cutting but he has done quite a few. He gets the tanks for free if he removes it.

 

[petes]

I got a scrap 250g tank from the local propane fill place for $10. They removed the fittings before they'd let me take it (I slipped the guy another 10... it was a cold day!). I flipped a furniture moving dolly (with casters) upside down to use as a roller cradle, used a shopvac output to blow air through a 1" PVC pipe into the far end of the tank for 10 minutes, then a propane detector to "sniff" the air in the tank before plasma cutting, just to make sure. It didn't register anything (threshold of the detector is 1% of the lower explosive limit gas concentration). I left the shopvac blowing while cutting the first end off anyway just to be safe. I used a piece of baling twine tied around the tank as a guide... should have used something a little less melt-able (like a thin strip of wood). I had to re-tie it a couple times, but it worked. Now I have THREE curved snow blades waiting for me to build a frame for at least one of them.

 

[Haywire]

You might use the wire as a guide for a sharpy marker then remove the wire and cut on the line. I still haven't cut the larger tank yet. Too many irons and too few "round to its".

Ian

 

[Mark @ Everlast]

Propane at any normal pressure and temperature cannot exist in a liquid state. When the pressure goes, so does the propane. Its the same as if you popped the top on a cola and left it sit for a week or so...It escapes.

 

[Egon]

Sorry Mark, liquid propane sitting in a bucket at atmospheric pressure will stay liquid for quite some time.:thumbsup:

And no, you don't want to put your finger in the bucket to see if it is cold!

 

[Johnp33]

Propane boils at -41F at sea level.