Pressure Relief at Propane Chiller
Pressure Relief at Propane Chiller
(OP)
Hello, I have to design a pressure relief valve (PSV) for fire situation for the shell of a propane chiller. In the shell, we have propane in evaporating service that removes heat from the produced gas stream in the tubes. At relieving conditions, the propane is above the critical pressure. How do I go about calculating the relief load for fire for this shell? I am doing basic engineering and do not need to dive into so much detail at this point.





RE: Pressure Relief at Propane Chiller
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Good luck,
Latexman
RE: Pressure Relief at Propane Chiller
Good luck,
Latexman
RE: Pressure Relief at Propane Chiller
Good luck,
Latexman
RE: Pressure Relief at Propane Chiller
Yes it is above the critical temperature.
thanks,
RE: Pressure Relief at Propane Chiller
Once you reach the PSV setpressure, gas has to be relieved at a flow rate such that the internal pressure remains constant. In other words, the rise in pressure that would have occured from the extra heat and increase in temperature over some time step is offset by reducing the mass in the chiller through the PSV.
My concern with a PSV in this service is that without liquid boiling to a vapor to keep the metal shell cool, the shell will reach temperatures which will compromise its ability to withstand the internal pressure and the pressure vessel fails. Water deluge or depressuring systems are sometimes used to prevent this.