drier for BBQ propan for r290 diy
 

Anyone with data on how much water is in bbq propane?

Is one filter dryer sufficient to remove the water for 5 pounds?
Would also add a fresh FD on line set.

Any less water in 1# bottles vs. 5 gal tanks?

Plan to charge by superheat and subcool methods.

Have seen a suggestion to also put propane bottle in freezer before charging. Charge cold on liquid side.

There's is no official spec for water content in fuel grade propane, only hd5 and commercial or hd10 grades. HD5 grade is for vehicles and has a minimum of 90 percent propane, and maximum of 5 percent propylene and 5 percent other flammable gases. HD 10 grade is the same, but allows up to 10 percent propylene and down to 85 percent propane. Commercial bulk propane is only required to be flammable. Nearly all consumer retail propane is HD 5 grade.

The only grades of propane with defined levels of moisture are research grade and refrigerant grade. Evidently, due to the nature of the refining process, water is a few layers down in the distillation column. During refining, the propane, propylene, and butane are much less volatile than the natural gas: methane and ethane go to the natural gas compressor and the propane butane mixes are drawn from the column during reflux. The water is mainly not even in the reflux tower. It is drained off the bottom of tank and the alcohols and other water soluble stuff goes elsewhere to be separated.

Strangely, the rest of the world has more lax standards for fuel grade propane. Mainly the allowed butane content is more, up to 30 percent in Europe and Asia. In Mexico, the butane content allowed is up to 40 percent.