Decanting Oxygen/ LPG --any problems?

[Mathuranatha]

G'day does anyone know if decanting oxygen is as easy as decanting LPG ?With LPG I just have a thick , high quality rubber hose I got made up ,that attaches the large , full bottle to a smaller empty bottle.Then I just elevate and invert the big one , open the taps on both and the liquid gas just runs into the lower one till it starts coming out the bleeder then i turn them off .Seems to work fine .

So can I do something similar with oxygen ?They don't have a bleeder so I guess the smaller bottle will have to be shaken to see when its 3/4 full , or would it matter if it was 100% full?Maybe the regulator wouldn't like liquid oxygen?

Anyone done it or got any ideas?

Mat

[specialist]

If it was me, I wouldn't do it, the oxygen is filled under pressure, that's how it gets it's liquid state. I don't think that you would be able to maintain the pressure and if you connected the two bottles, it would only fill until the pressure equalized, I's reckon that would only give you gas in the second bottle, not enough to make it worthwhile.

Just my idea.

Robert

[phelum]

G'day does anyone know if decanting oxygen is as easy as decanting LPG ?
As a follow-up, I wouldn't try it either. Oxygen isn't a liquid in the tank; it is just gas at a very high pressure, say 2500 psi (or 16.5 MPa for the younger folk here).

Also I think the suppliers of oxygen cylinders would take a very dim view of anything like this.

[specialist]

Thanks Steven for the clarification on that.

Robert

[Grahame Collins]

I must highly recommend against it. A most dangerous practice indeed.Both, in fact are extremely dangerous exercises.

Firstly you should not decant LPG without proper gear and knowledge. YOU MUST USE A LPG DECANTING CYLINDER.Talk with someone from the gas company who knows, for goodness sake!

Secondly each large full OXYGEN cylinder has(nine cubic meters and 2000 PSI OR MORE) that is more than enough to kill you very dead when something goes wrong. There can be enough stored energy to level a house if it all it lets go at once.


Just in case I was not plain enough.

NO ! DO NOT DO IT

Read this
http://www.safework.sa.gov.au/uploaded_files/ds6i.pdf
Load and read the MS PowerPoint
www.adelaide.edu.au/hr/ohs/hazmanagmt/safe_handling_gascyl.ppt

Once the powerpoint opens click on <view> and then <slide show> and press enter to change each slide.the section on decanting is towards the end.
Grahame

[DavidG]

It is possible to fill small oxygen bottles from a large one but the special pump and equipment required cost thousands.

[Vernonv]

LPG decanting is pretty safe - as long as you take some "common sense" precautions (do in well ventilated area, away from sources of ignition) and use the correct hoses and fittings.

Oxygen on the other hand (and as the previous posters have said) is very dangerous and it not something you should attempt.

[J.E. Mike Tobey]

If there are leaks of oxygen, your clothes can become super-saturated. A tiny spark and you are a Joan of Arc stand-in. You are toast. You are dead or wish you were.mt

[Mathuranatha]

I googled "decanting liquid oxygen".OK it looks like folks ,in the US anyway ,that need to breath oxygen keep a big tank of liquid oxygen in their house and decant out of it into smaller bottle when they want to go shopping.

Then interesting thing , in the quote following is that the big bottle of liquid oxygen is only for emergency and for decanting into small bottles when they go out . The rest of the oxygen they generate them selves at home , 6 lites /minute .Renting oxygen bottles adds up + if you live out of town ,ant the drive is cut when the river is up etc---would be really good to make my own oxygen --does anyone do it?

Quote about the decanting>>>>>>>>>>>>>>>>>>>>>>>>>>>
Let me first describe a typical home setting for a person who needs oxygen 24/7. It is one of stringent limits. Most home oxygen set ups start with an Oxygen Generator which is powered by house current. It produces up to 6 liters per minute of enriched air (oxygen) using a compressor and other elements. It is normally piped to a patient via a plastic tube. Anything over 100 feet is a concern since additional length in a fixed size tube causes a reduction in flow. So you can get about 200 feet from the generator if you crank up the setting to about twice what the doctor prescribed. For example, if the prescription is for 2 liters, then crank it up to 4 and at the end of the 200 foot run you will get about 2. So if the patient like to garden, you can snake the plastic tube outside and into the garden. That allows the patient to enjoy the joys of gardening for example.
The next piece of equipment is a liquid oxygen tank that can hold for 21 liters to 41 liters of liquid oxygen. The tanks are heavy because of the insulation and regulators. A 31 liter tank weights about 130 lbs so it is not easily transportable. It is about 18 inches in diameter and about 40 inches tall. This tank is provided in the home as a primary source to decant liquid oxygen into portable (about 3 lbs total) tanks that the patient can carry about. It also acts as a backup oxygen source, if the house current should fail like in a power outage. <<<<<<<<<<<<<



Mat:)

[journeyman Mick]

Mathuranatha,
in Australia AFAIK, oxygen for human consumption is a drug and can only be administered under medical supervision. The oxygen/nitrogen balance in the air we breathe is about right for humans and any long term consumption of raised oxygen levels can lead to some very bad side effects. If I remember correctly it can lead to blindness due to super saturation of some of the tissue in the eyes as well as convulsions. Gasses stored under high pressure and backyard decanting are a potentially lethal combination and if you're foolish enough to try it you may experience Darwin's theories first hand.:o

Mick

[Grahame Collins]

Forum Members
I have received a reply to an email that I was concerned enough to send to the Australia LPG association.
In it I included a cut and paste of the original post. My concern is that poor information picked up from this forum may lead to a disaster for someone . Lets try to avoid any, OK.any Lets do any procedure requiring a degree of safety, in the recommended manner.

This is what the experts say, please read

Hi Grahame,

Thanks for email. I agree, there is a procedure to follow to decant LPG and the procedure outlined in the email is not correct, and is dangerous. The correct procedure is in AS 1596 2002 (App L). What the person does not realise that is:

* the rubber hose will likely contaminate the LPG (LPG is a strong solvent)
* the rubber hose and fitting may not be rated to withstand the pressures developed in a decant operation, and fail
* liquid LPG will cause severe cold burns on contact
* tipping a large cylinder over may introduce rust or scale into the valve parts of the cylinder, making valve closure difficult or impossible, leading to an uncontrolled leak



For liquid oxygen, the situation is many times more hazardous. A disaster waiting to happen as you infer.

We have a CD on the correct procedure for LPG, which we give to our members. I do not know of any documented procedures for oxygen.



regards



Steve Reynolds

LPG Australia

[Mathuranatha]

Thanks for your concern.The hose was made up 4 me specifically for decanting by a company specializing in LPG gass appliances ,babecues ,bottles and fittings etc.The hose was expensive , top of the line high pressure .At the time we were running 8 or 10 mantel gass lights on small bottles every night and refilling them from a bigger bottle every 2-3 days .The bigger bottles were new , didn't have a problem with rust .

Anyway , the LPG just seemed so straight forward and easy that I thought if decanting oxygen was as easy it would be a lot easier to have a small oxygen bottle for mobile cutting in my rambling scrap pile of old truck ,car , caravan chassis etc.I,m getting to old to drag a a G size oxygen and 45kg LPG up into the lantanna whenever I need a piece of rhs or chassis rail .

Anyway its looking like its all old dinosaur technology ,and I should get me one of them new fangled plasma cutters .

Thanks Mat.