Integration of Damage Mechanism Review with Process Hazard Analyses

PresentationSignificant releases of highly toxic and flammable materials have occurred in various industries as a direct result of corrosion effects and other damage mechanisms. Examples of such events can readily be found in petroleum refineries and ammonia refrigeration facilities. Understanding and identification of these damage mechanisms and locations of susceptibility play a critical role in limiting the likelihood of loss of primary containment, which can have serious safety consequences. Process Hazard Analysis (PHA) provides a thorough and efficient method for systemically reviewing complex systems for safety concerns. A commonly applied PHA method is the Guide-Word Style Hazard and Operability (HAZOP) approach, which breaks complex systems into focused sections called nodes. This methodology can be augmented to systematically address the effects of various damage mechanisms. Possibility of corrosion and other damage mechanisms can be included in each node through the addition of a new deviation dedicated to these phenomena. The PHA Team with the help of a subject matter expert reviews the various mechanisms unique to a particular node that can cause loss of integrity. PHA discussions of damage mechanisms should address normal and abnormal operating conditions. The timing of progression of damage mechanism effects and established methods for discovering the damage (detection safeguard) should be explicitly noted. It is important to note that such discussions require participation of experts in metallurgy, corrosion mechanisms, inspection techniques, and process chemistry. The proposed method has been applied successfully in identifying potential vulnerabilities and improvements to minimize the risks associated with corrosion. Specific examples are shown from actual studies addressing systematic analysis of damage mechanisms and the lessons learned from those studies