Justice100
Chemical
- Jun 18, 2008
- 49
I have a tank filled with cryogenic hydrocarbon. The emergency relief vent (weighted pallet with hinge, something like this - is set at 130 mbar with 20% allowable accumulation and there is an inlet line 10m long (required as double walled tank). The tank is to be repurposed for a different cryogenic HC.
I have calculated the emergency sizing case relief rate but I am struggling with the relief vent capacity charts. The capacity charts are in air at standard conditions but my relief fluid and relieving conditions are very different so I assume I use API 2000 equation D.35 to convert my relief rate at sp +20% to air at standard conditions. I can then use the capacity charts. Is this the correct approach? Also, how can you account for the inlet line DP? Similarly how do you account for pressure losse due to inlet/outlet piping for a PVRV using these charts?
I have calculated the emergency sizing case relief rate but I am struggling with the relief vent capacity charts. The capacity charts are in air at standard conditions but my relief fluid and relieving conditions are very different so I assume I use API 2000 equation D.35 to convert my relief rate at sp +20% to air at standard conditions. I can then use the capacity charts. Is this the correct approach? Also, how can you account for the inlet line DP? Similarly how do you account for pressure losse due to inlet/outlet piping for a PVRV using these charts?