Calculations Help: Working Out SF6 Usage in Litres

  • Thread starter Thread starter Scara
  • Start date Start date
  • Tags Tags
    Calculations
Click For Summary
SUMMARY

The discussion centers on calculating the usage of SF6 gas in a 67.4-litre vessel filled to 6 Bar. The density of SF6 at 20°C and 6 Bar is approximately 46.5 kg/m³, indicating that the gas is superheated under these conditions. Participants emphasize the importance of distinguishing between gas and liquid measurements, suggesting that the user clarify whether they need to calculate gas volume or liquid volume for the vessel.

PREREQUISITES
  • Understanding of gas laws and behavior, particularly for superheated gases.
  • Knowledge of SF6 properties, including its density at various temperatures and pressures.
  • Familiarity with pressure measurement units, specifically gauge and absolute pressure.
  • Basic thermodynamics, especially regarding phase changes and saturation temperatures.
NEXT STEPS
  • Research the ideal gas law and its application to SF6 calculations.
  • Learn how to convert between mass and volume for gases, specifically using density.
  • Investigate the properties of SF6 at different temperatures and pressures for accurate measurements.
  • Explore methods for determining liquid volume requirements from gas measurements.
USEFUL FOR

This discussion is beneficial for chemical engineers, HVAC professionals, and anyone involved in the handling or calculation of SF6 gas usage in industrial applications.

Scara
Messages
2
Reaction score
0
Hi Folks,

Not the best at this so hoping somebidy can help me.

I have a 67.4 litre vessel and I'm filling it with SF6 to 6Bar. Can I work out how much SF6 I'm using in litres?

Is this a dumb question? should nI be asking what weight I'm using.

I've been asked to supply usage in litres.
 
Engineering news on Phys.org
Hi Scara. I can give you the density of SF6 if you can provide the temperature and verify the pressure is gage and not absolute pressure.
 
The sf 6 is at room temperature around 20deg Celsius . Pressure measured on vessel with gage.
 
At 6 barg and 20 C, density is roughly 46.5 kg/m3. The saturation temperature at this pressure is -19 C and at atmospheric pressure the saturation temperature is -68 C.

So at this pressure and temperature, you have a superheated gas. I'm not sure why or how you could put that into liters, but I wonder if there is a liquid source and you're being asked to determine how many liquid liters are needed for this 64.7 L vessel, in which case you need to define the conditions of the liquid source.
 

Similar threads

Undergrad Calculating Pressure Change Filling Gas Cylinders
  • · Replies 69 ·
3
Replies
69
Views
7K
How many ppm of O2 does H2O2 add to water?
  • · Replies 5 ·
Replies
5
Views
4K
High School Secondary Upper and Lower Bound QUESTION
  • · Replies 11 ·
Replies
11
Views
1K
Controlling two valves with different flow-rates to achieve mixing
  • · Replies 23 ·
Replies
23
Views
5K
Engineering Calculating the mass of air in a pressurised air tank
  • · Replies 14 ·
Replies
14
Views
3K
Pressure differential through orifice plate
  • · Replies 6 ·
Replies
6
Views
3K
Question re electrochemical marking of stainless steel
  • · Replies 6 ·
Replies
6
Views
2K
Calculate the work done in an external combustion engine
  • · Replies 3 ·
Replies
3
Views
6K
Excel spreadsheet calculating costs
  • · Replies 3 ·
Replies
3
Views
2K
Need help- calculating clearing of bubbles from a microfluidic channel
  • · Replies 4 ·
Replies
4
Views
2K