propane numbers

Ventana view wrote:We have a new home and to fill our propane tank (it's on the roof), you need a tanker that has extra long hoses. Here are two companies that provide this service in LV/ES. 1: Martin Big Tank Propane Gas (+52 612 348 3743). 2: Global Gas La Ventana (+52 612 159 3974).

Originally Answered: Is LPG and propane the same thing?
Yes. And no.
In my area, at 60-north in Alaska in the sub-arctic, all “LPG” and “propane” sold locally is all propane: C3H8. It has to be if it’s going to work for you as temperatures approach -40. Propane’s boiling point is -44F / -42C so it can’t produce any vapor below that temperature.

In other, more temperate or tropical climates, LPG contains some or a lot of butanes (iso-butane, n-butane). That raises its boiling point and reduces its vapor pressure. From my northern perspective, that’s always bad, but where it’s always cool, warm or hot, there’s no downside and one upside is at higher temperatures, the lower vapor pressure doesn’t stress the canister/cylinder as much.

Also, the butane is denser in both mass and heat energy per liquid volume so you get more heat output per gallon or liter of a blend than pure propane.

Lastly, and this is going deep into economics and chemical engineering, all the separation and cracking processes in a refinery cost money and energy to perform. It’s more economic to sell a chemical compound as it is than to perform some chemistry to turn it into something else.


In northern climates and especially in winter, butane is nice to add to gasoline to increase the Reid Vapor Pressure (RVP) from its lower summer-time level (to minimize vapor lock and fugitive emissions of VOCs) to a higher RVP (more volatile) blend in winter to facilitating cold starting in gasoline/petrol cars. So, conveniently, the butane has a matching desired and undesired uses:

In snow country: butane in gasoline helps cold starting. While butane in LPG would limit its use in frigid weather.

In warm climates: Butane should be minimized in gasoline to avoid vapor lock, but works fine in LPG because adequate vapor pressure is always maintained in warm weather (and you get more heat value per liter of liquid).