Dear Experts
I exposed with design of some sour pipeline in remote area (unmanned).
The pipelines are underground due to safety limitation (0.6 to 20 wt.% H2S).
Our concern is that what should be safe and standard design for depressurizing.
It is obvious that quick (e.g. 15 min) depressurizing is not practical for pipeline.
However, long depressurizing (e.g. 10-40 hr) may not have any benefit during issues such as pipeline rupture.
Some safety engineer told me pipeline rupture is a low frequency accident and should be ignored for pipeline flare design (depressurizing).
Finally which type of flare we should use as it is not automatic.
Some designer proposed flare with gun and small sterile area. However, it is not clear procedure for opening of inlet line to flare
and also ignition of flare after opening.
I search most international code and standards and there is not any written procedure and policy for such design.
G.B.