Resilience of Process Plant: What, Why, and How Resilience Can Improve Safety and Sustainability

Resilience is the ability to restore performance after sustaining serious damage by a usually unexpected threat. This paper analyzes resilience of process plants as there are oil and gas refining, chemical manufacturing, power-producing plants, and many more. Over the years, plant safety has shifted from retrospective to proactive measures. Safety is important from many points of view, such as protection of workforce and nearby population, but certainly too from an economical and sustainability aspect. Pro-action requires predictive insight of what in the process can go wrong because of internal or external disruptive disturbance. Over the years, to that end, much effort was spent developing risk assessment methods and management. However, risk assessment has proven to be fallible because of various uncertainties and not the least by overlooked or unknown threats. To protect against those upsetting threats, measures can be taken up to a certain limit. These start in designing error-tolerant equipment able to be receptive to early warning signals during operations, responding to those with 'plasticity' of mind (that is, an organization and its leadership especially able to think 'outside-the box' for coping with unexpected situations), and finally, to deploy effective emergency response and able to recover from damage quickly. The paper presents a summary/review of nearly a decade of research work at the Mary Kay O'Connor Process Safety Center at the Texas A&M University to develop the concept and the techniques to realize a resilient plant, so far with a focus on chemical plant. It is, however, still a 'work-in-progress'; potential is large. Besides the conceptual details, cases are presented that show how human and technical factors, combined in a socio-technical system, can lead to a broader plant safety insight enabling more effective risk control and increased resilience. These cases have up to now only considered warning signals and possible management action, while still limited to internal threats. Hence, aspects of equipment design and recovery should be further considered, also in the light of the dynamics of present-day business environment.