Lowering pressure for LPG

[JasonLim]

What process or machine are used to separate propane or butane from LPG?

Is there a machine or process that lower a LPG pressure?

The current state of the LPG is 21% Propane & 79% Butane. It range from 6 bar - 7.5 bar, sometimes even higher. Is there any way to lower it below 4?

Thank You

 

[BigInch]

It's much easier to add the short component to the mix to get the right percentages than it is to remove the long component.

To reduce pressure increase Butane in the mixture, or lower the mixture's temperature and ... keep it low.

see the attached propane-butane mixture table

Only put off until tomorrow what you are willing to die having left undone. - Pablo Picasso

 

[BigInch]

BTW, it looks like there's an error in that chart.
30% Propane
70% Butane
at 80F
should be more like 55.5 rather than 45.5

Only put off until tomorrow what you are willing to die having left undone. - Pablo Picasso

 

[JasonLim]

Thanx BigInch

but the chart that you gave me is differ from the LPG pressure I'm currently using.

for example: 20/80 @ 80F 43.9 PSI (roughly 3 bar). But the one I have is 21/79 @ 80F 89.9 PSI (roughly 6.2 bar)


any explanation on the huge difference? some of the engineers i'm working with suggesting to increase the propane instead.

 

[BigInch]

I think my chart agrees with this one very closely too.

http://www.engineeringtoolbox.com/propane-butane-mix-d_1043.html

What is the source of your chart?

Only put off until tomorrow what you are willing to die having left undone. - Pablo Picasso

 

[dcasto]

well, lets answer your questions 1 at a a time.

What process or machine are used to separate propane or butane from LPG? Its called distillation.


Is there a machine or process that lower a LPG pressure? Yess, it's called a refrigeration system.

The current state of the LPG is 21% Propane & 79% Butane. It range from 6 bar - 7.5 bar, sometimes even higher. Is there any way to lower it below 4? Lower the temperature to 70F.

Your charts may not match because of

1) what are the units of percent, weight, volume, or mole?
2) what is the butane, iso, normal, or a mix?