SLM Propane relation to BTUs/Hr 1

[MartinusG]

What is the relation of SLM (Standard Liters per Minute) of (US) LPG usage with BTUs/Hr?
Conversions with BTU value per Gallon of Propane give me odd numbers! There is probably something I am missing between Liquid and Gaseous?
(1st time using Eng-tips, so I hope I am in right Forum?)

Thanks.

 

[franzh]

Propane (US blend HD-5) has 91,500 BTU's per gallon; 2,488 BTU's per cubic foot vapor, 21,548 BTU's per pound, 36.38 cubic feet vapor per liquid gallon, 8.66 cubic feet vapor per pound, 184 BTU's latent heat of vaporization per pound, 773 BTU's latent heat of vaporization per gallon. The factor of propane vapor to liquid is 270.
You will need to do the math to convert these numbers to metric.

Franz

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[patprimmer]

Franz.

Just to be nit picking, I take it those figures presume US gallon, not imperial gallon, and the vapour is at STP.

Regards
pat pprimmer@acay.com.au
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[franzh]

Yes, standard US gallons, and the vapor temps are at 60°F.
As you are aware, propane vapor is quite reactive to temperature changes, a 10° F (at 60°F) increase in temperature can result in a 1% increase in volume (not mass). The rate of expansion increases with the temperature.

Franz

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