Process safety management of a fuel gas conditioning facility using fault tree analysis

Abstract

This paper discusses a process hazard management study of a fuel gas conditioning facility based on state-of-the-art fault tree analysis techniques. This facility lowers the water and hydrocarbon dewpoints of a high pressure fuel gas exposed to frigid temperatures during distribution. Using hazards checklists and guidelines as well as internal reviews, various process hazards were identified for this facility. Computerized fault tree analysis techniques were used to identify the failure sequences which could lead to process hazards, and analysts used these results to evaluate the impact of specific hazards upon process safety. Through recommendations presented in the study, the facility owner gained an increased awareness of potential problems and made modifications to reduce the possibility of a hazardous condition and subsequent catastrophic failure.Dans cet article, on prtsente une ttude de gestion du risque d'un syst&me de conditionnement de gaz combustibles baste sur les techniques les plus rtcentes d'analyse par arbre d'erreurs. Ce dispositif a pour objectif d'abaisser les points de roste de I'eau et des hydrocarbures dans un gaz combustible a haute pression qui doit Ctre expost a de basses temgratures lors de sa distribution. Plusieurs risques ont pu &tre identifits pour cet appareillage en utilisant les listes de vtrifications et les consignes donntes ainsi que des rapports internes. On a utilist des techniques d'analyse informatiques par arbre d'erreurs afin d'identifier les stquences de malfonctionnement susceptibles de conduire a un danger et des analystes ont utilist ces resultats pour tvaluer I'impact d'tvtnements fortuits sptcifiques sur la stcuritt du proctdt. Grice aux recommandations prtsenttes dans I'ttude, le proprittaire de I'installation est devenu plus conscient des probltmes pouvant survenir et a pu faire des modifications pour diminuer la probabilitt des catastrophes qui peuvent en dtcouler. his paper describes a study undertaken by Westinghouse T to evaluate process safety for a fuel gas conditioning facility through the application of hazard identification and assessment techniques (Leach et al., 1985). At the request of the client, Westinghouse used qualitative fault tree analysis to evaluate process safety and to recommend modifications to reduce the risk to process safety. Additionally, the customer was able to use the results of this analysis to: -Identify corrective action to avoid safety hazards and to minimize the possibility of financial loss and unscheduled downtime caused by system failures, accidents, and operability problems -Create a "living" system reliability model to continually evaluate the cost and benefits of proposed process modifications and operations changes -Identify those areas where increased operator awareness could most readily increase safety or reduce financial risk, or where relaxed operating procedures would minimally affect risk or reliability -Improve public relations by making a conscientious effort to reduce risks to public health and safety Computeriz...