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Unregistered
05-02-2006, 09:29 AM
I have liquid O2 in tanks. We measure it by inches. The co. charges us by the ccf. How do I convert inches into ccf?

Robert Fogt
05-02-2006, 05:10 PM
The inches used is most likely inches as a unit of pressure. Such as inch of water, inch of air, inch of mercury, etc.

Originally it was the height of a column of (mercury or water or air) that excerted the same pressure as the atmosphere. Today though it is generally just standardized to a specific value as temperature changes the original definition.

Now back to your original question. How do you convert pressure to volume. I don't know of any way to do that. Though it feels like it would be possible.

Mrs X
05-02-2006, 10:19 PM
Does the "inches" measurement tell you when to get the tank refilled? If this is the case, it could be the depth of the liquid oxygen in the tank. You could make some attempt to work out the volume of the tank, and draw a correlation between volume and depth. (I don't know what ccf stands for sorry, I'm assuming it is a volume measurement).

A note about pressure: When the tank has just been filled, the pressure will be quite low, as all you are measuring is the pressure in the gas space above the liquid. When the tank is nearly empty, the gas pressure can be quite high, due to plenty of gas in the gas space above the liquid. ALSO, the pressure can be quite high when the tank is nearly full, and it can be quite low when the tank is nearly empty.

Robert Fogt
05-03-2006, 12:56 AM
CCF stands for hundred cubic feet. The C being the Roman Numeral C for 100. It is fairly common for utility companies (such as the gas company) in the U.S. to use this unit, but seldom seen elsewhere.

Unregistered
07-19-2006, 06:14 AM
i work for a gas supplier. all liquid gas deliveries are measured in either gallons of liquid, or cubic feet. most often, they are billed to you by cubic feet.

as for the inch to volume conversion, it is different depending on the size tank you have. a company called MVE currently manufactures the bulk tanks, and they have charts that give you the conversion for each inch increment.

for instance, in a 3000 gallon oxygen tank, the average inch is approx equal to 1,902 cu ft.
keep in mind this is an average. an inch of water at the bottom of the tank is much different than an inch at the top due to the construction of the bulk tank itself.

I would contact your supplier. They should be able to supply you with the conversion chart for your tank.

Unregistered
10-05-2007, 11:51 AM
Pressure and volume can be interconverted using some laws of chemistry, such as the Ideal Gas Law and Van der Waals equation, but using these would probably not provide the most accurate or practical solution for your situation.

(visit Wikipedia for explanation)

Mrs X
10-07-2007, 02:33 PM
Pressure and volume can be interconverted using some laws of chemistry, such as the Ideal Gas Law and Van der Waals equation, but using these would probably not provide the most accurate or practical solution for your situation.

(visit Wikipedia for explanation)
Liquids of any description are not obeying the ideal gas law.

Unregistered
11-07-2007, 12:47 PM
Question, How many liters are in a lb of oxygen?

Unregistered
12-04-2007, 09:33 AM
We have tanks that are 180Liters that weigh 293 lbs.
My question is if I run 70L/min how long will one tank last?

Mrs X
12-04-2007, 09:21 PM
We have tanks that are 180Liters that weigh 293 lbs.
My question is if I run 70L/min how long will one tank last?
180/70 = 2.57minutes, or 2minutes and 34seconds. the 293 pounds is a red herring.

Unregistered
12-30-2007, 11:08 PM
I will use specs from a 180L Taylor-Wharton cryogenic liquid tank to try and answer your question.

For a 180L tank, the usable capacity is typically 169L and will hold 388lbs of liquid oxygen at 16bar of pressure at 21C - let's assume that for you, too. It will evaporate at an average of 1.2%/day, so we will calculate the maximum duration, and then then your actual duration depends on how quickly you use it.

To find the duration, you first have to convert liquid oxygen into a gaseous oxygen equivalent, because the liquid will expand when it evaporates into a gas. Liquid oxygen expands into gaseous oxygen at a rate of 860:1, which is why it is so efficient to deliver oxygen in liquid form. So 169 usable liters x 860 expansion factor leads to 145,340 gas-equivalent liters, which is usually expressed in cubic meters - 145.34m3 - another way to say it is that this one small liquid container delivers more oxygen than a pallet (12) of large 50L gas cylinders pressurized up to 200bar (~3000psi) and delivered with a forklift.

At 70 l/min you have 2076 min or approximately 34 hours maximum duration. If you use it all in one session you will get that much. If you spread it out over 2 months you will get far less because most of the contents will be lost to evaporation.

Unregistered
01-10-2010, 05:36 PM
Post # 11 is correct not #10

Ravi Sinha
09-05-2010, 08:57 PM
i have liquid Oxygen in Road tanker. i received the quantity in Kgs.i want to know the measuring system how i actually receice the liquid quantity in Kgs. from road tanker to Liquid Oxygen receiver tank

Mrs X
09-06-2010, 11:38 AM
Post # 11 is correct not #10

Depends if they were using is gas or liquid. :)

Mrs X
09-06-2010, 11:40 AM
i have liquid Oxygen in Road tanker. i received the quantity in Kgs.i want to know the measuring system how i actually receice the liquid quantity in Kgs. from road tanker to Liquid Oxygen receiver tank

The density of liquid oxygen is about 1.2, so divide the kg by 1.2 to get to litres.

Unregistered
12-20-2011, 03:58 AM
1 tonne of liquid Oxygen is equal to how many cubic meter at what condition of pressure and temperature

Mrs X
12-21-2011, 09:48 AM
1 tonne of liquid Oxygen is equal to how many cubic meter at what condition of pressure and temperature

Are you wanting to know how much gas could be produced from 1 tonne of LO2?

drms reddy
02-23-2012, 12:31 AM
1 litre of liquid oxygen gets converted to 860 liters of gaseous oxygen.

Unregistered
05-02-2012, 12:50 PM
In order to calculate how long a supply of gas will last, you need:

The tank factor

the tank pressure

and the liter flow

the formula:

The tank pressure times the tank factor devider by the liter flow= x minutes