I got hold of the inbreathing values (from FEED), both for liquid out and thermal venting.
I used API 2000 to do my own calculation and while the required blanketing flowrate for liquid out checks out, the FEED values for thermal venting is roughly 2-3x than what is indicated in API 2000.
The tanks in question have temperatures above 120°F (the tanks have no insulation) and as per Sec 4.2.5.14 of API 2000, cases like these require more detailed analysis. I think that this may be the cause of the discrepancy in values.
Since I haven't done this kind of task before, can anyone point me out to the right direction on how to deal with the more detailed analysis? What I have in mind is doing some heat transfer modelling of the whole tank during a rainstorm (worst case) and calculating the decrease in vapor volume inside the tank.
BTW, the fluids concerned are 25% DEA and sour water.
Thanks in advance
Edited by Dacs, 28 August 2009 - 01:50 AM.