Vapor Pressure

[BB3242]

Howdy all,
I need to find the Vapor Pressure of VGO 100-120 Deg F, Asphalt 300-350 Deg F, and MCB 200 Deg F. I understand about their characteristics I have just hit a wall with the vapor pressure. Would anyone be able to point me in the right direction for a website or source that is credible? Thanks for all of the help.

 

[JLSeagull]

Do you really need the vapor pressure value or just something to confirm that no flashing exists? Sometimes for my initial calculations (control valves, orifice plates, etc.) on such stuff when I don't have the vapor pressure I just enter 1 psia and the calculations work. Once I replace with the vapor pressure nothing changes in the result.

 

[BB3242]

Well I am doing a line loss survey to see why a couple of pumps are cavitating and the NPSHa among many things is a variable of Vapor Pressure as well. I am already on the line of NPSHa not being enough for the NPSHr. One foot in either direction could be good or screw me.

 

[25362]

The general idea is that both LVGO and asphalt, as obtained from a vacuum tower, should have very low vapor pressures at those temperatures, especially if they did not suffer any thermal cracking.

As for the MCB, if it means Medium Curing Bitumen, it all depends on the kerosine flux properties.

If the VGO vacuum tower withdrawal was done at 10 mm Hg and 450 deg F and the bitumen's was at 750 deg F and 25 mm Hg, both vapor pressures would be well below 0.1 psia at the given temperatures. Which corroborates JLSeagull's message.