Damage mechanism and barrier identification on hydrogen production unit using innovative methodology for risk assessment

Abstract

In the oil and gas industry hydrogen is used in a large number of processes, mostly in hydroprocessing units such as hydrotreating, hydrocracking and other refining processes that increase the hydrogen-to-carbon ratio. To satisfy the need for H-2, refineries usually have a dedicated Hydrogen Production Unit (HPU). Given the wide range of processes that HPU supplies and the fact that cost of operation of this kind of unit is rather high, it stands to reason that any kind of interruption in unit operation will affect the whole refining process. From Risk Based Inspection (RBI) point of view, HPU can be a very challenging unit to deal with, primarily due to the wide range of operating processes conditions as well as different operating fluids. As a result of applying the innovative methodology for risk assessment, it is shown that significantly higher number of damage mechanisms are identified in regard to the number of damage mechanisms that would be identified by applying traditional methodology, due to the fact that both active and passive damage mechanisms are identified. Concept of barriers such as measures that are able to restrict, reduce or preferably eliminate damage mechanisms identified in HPU are introduced and discussed. Innovative methodology was successfully applied in the case of a refinery in the Middle East.