(47bc) Evaluating The Need For Depressuring Systems - A Methodology

Evaluating the Need for Depressuring Systems - A Methodology

A thorough Overpressure Protection Philosophy should consider all options for overpressure protection, and should not be limited to relief devices and rupture disks - they are not the only line of defense.

Another effective means of overpressure protection are depressuring systems. These can be used to mitigate against vessel leaks by reducing inventory or leakage rate; or to mitigate against the effects of external fire.

ioMosaic recently conducted a site-wide overpressure protection study for a large LNG production facility. Part of this scope involved assessing equipment items which did not have a depressuring system installed, and determining if a depressuring system was warranted, in addition to the equipment's other overpressure protection.

This paper outlines the methodology used to determine the need for a depressuring system, and also highlights some of the issues to be aware of when designing a depressuring system.