I dont know if i am doing the rigth question to you guys, if you simulate with pipephase in a gas phase option, the program choose by default: moody correlation pressure drop method, i know that it is the for friction factor, but what is the equation for the pressure drop? is it the isothermal...
montemayor:
you have a very good points
1) the relief duration, there are a long reliefs, so, as you say the fluid circulating cool-down the line and make the process isothermal. But how can i assume adiabatic model if the header is not insulated?
2)Considerate that the fire heats the header...
montemayor: you are rigth the vapors from the tanks are saturated, but when you mix propane vapors at -50°F with n-butane vapors (saturated) at 26°F or/and iso-butane (saturated) at -6°F it will form liquid unless you have heating from ambient (ambient 66°F). Remember the header is not...
Ok i uderstand you, i was refering the paragraph that say:"simple rules cannot be expected to cover all installations. Good engineering judgment should be applied to select the flow basis most appropiate to each case.".
That is why a asked your opinion about use rated capacity in a multiple...
i appologize for my english, is not my native language, i am trying to do my best.
Yes the vapors coming from the tank(from the roof) are going to a vent header and then to the burning pit (it is an old LPG plant. In the burning pit it burn liquid stream and vapor stream. The vent is vapor phase...
The API 521 seem to let open the posibility to considerate another flow instead the required capacity, well it seem to me in my point of view. What is your opinion?
best regards
I have an interesting issue:
We have three (3) storage atmospheric tanks that contain: propane @ -50°F, iso-butane @ -6°F and normal-butane@ 26°F each of one. The tanks are insulated and have a vent header, each tank has a vent valve connected to the header, the valves are control type and...
thanks to all of you.
pleckner you are rigth, it is a gas /vapor relief (i forgot to mention it).
I asume that for a multiple valve scenario is the same for each valve: discharging the flow calculated in this way.
In the API 521 is not very clear if you can use the contingency flow or the...
a question for you guys:if i have a PSV installed (for whatever reason) and it opens ¿what is the flow trough this valve? ¿is the one calculated by a contingency (fire for example)? or ¿is the calculated by the actual orifice with the upstream pressure ?(assuming critical flow).
thanks for the help
halizo
In the real world when a PSV (installed) opens ¿what is the flow trough this valve? is the one calculated by a contingency (fire for example)or is the calculated by the actual orifice with the upstream pressure (assuming critical flow).
thanks for the help
