Two part propane question?

Question

What is the average pressure drop per distance for 2" propane piping?
What is the average pressure in a 500 gallon propane tank when it is full?
-Are there safety concerns when bumping up the pressure 5 pounds if I use a direct burial line?
-What thumb rules will I need to know?
-How much propane will I need to last 9 days if I want to supply various equipment using approximatly 1.7million BTU/hr at peak operating times?

Answer 1

Commercial propane has a vapor pressure of about 210 psi at 100 degrees F. Since you never fill a propane tank completely full the vapor pressure is all the pressure you will have in the tank.

Assuming you meet any local code requirements, propane lines can be buried safely. As to what you mean by "bumping up the pressure 5 pounds" I have no idea. That needs more explanation as to what your intentions are.

Most users of propane operate at pressures much below the propane vapor pressure, therefore; there will need to be a pressure regulator some where between the tank and the end use point. That along with the usage rate will determine the pressure drop in the 2" line.

The gross heating value for propane is about 21,500 btus per pound or 91,000 btus per gallon. The net heating value is approximately 8% less than the numbers just stated. With this information you should be able to estimate the amount of propane needed for any give time.

I would suggest you talk with the local propane supplier about your application. They can probably give you much more specific information to help you with your questions.

Propane is potentially a very dangerous fluid if not handled properly. You need some expert help to keep you safe.

Answer 2

Too much missing information.

Pressure drop will depend on flow rate at zero flow rate pressure drop is zero.

Don't know the pressure but propane is a liquified gas so the pressure should remain fairly constant in the tank from when its full to when it's almost empty and is independent of the size of the tank.

Don't see a problem with running a buried line at 5 psi, not sure whats normal for propane but there are probably some code issues for running it into a building at that pressure. It is more dangerous.

Peak usage is the number you need to use for sizing your lines. But to determine the tank size for 9 days you need the average usage.