Event & target likelihood | Cause & likelihood | IPL (Integrated Protection Layers) and its PFD (Process Failure On Demand) | Mitigated likelihood | ||
Merging of propane stream with Natural Gas main stream, causing solidification of flow in MCHE
1E−6 | Tube rupture inside the heat exchangers
I.E−1 | Process design | Alarms | SIS (PLC) | 1E−7 |
Design the pipes to hold pressure much higher than that of the process
1E−2 | An alarm should be present to detect whether the composition changed of the Main stream, if so operator should stop process immediately
1E−1 | Logic in PLC once a composition change detected, shuts the propane cycle and directs part of main stream to the flare
1E−3 |