Ageing management and monitoring of critical equipment in petrochemical applications: an Italian case study

Over the years, environmental health and safety issues have seen an ever-growing interest developed becoming a crucial and strategic aspect of today’s business operations. Companies have focused efforts and resources on tasks, techniques, and rules to guarantee high protection level of health and safety at work according to national and international laws. In 2015, Legislative Decree No. 105, was issued in Italy, implementing the Directive 2012/18/EU on the control of major accident hazards involving dangerous substances. This Directive made clear the obligation to adopt a risk monitoring and control plan associated with the aging and corrosion of plants and equipment by operators of industrial plants. In this context, this work proposes a methodology, consisting of a structured approach, aimed at identifying the factors that have an impact on ageing process of industrial devices. In the first step, the root causes that can accelerate or retard the deterioration and damage process associated with time in service have been defined through an ageing fishbone (AFB) approach. In the second step, the effects of these factors have been assessed through a specific tool index-based by considering a rewards and penalties model. This methodology is applied to the critical equipment operating in the Mild Hydrocracking unit of a refinery located in southern Sardinia (Italy). The results show the practical applicability of an effective and easy to implement aging management tool aimed at ensuring safety and reliability of the equipment in a real use-case. Simplicity and relatively easy physical interpretation of the criticalities allow managing all potential aging effects resulting in key aspects to support the risk-based analysis.