World-class ammonia and methanol plants typically produce more than 500,000 metric tons of ammonia or methanol per year. These plants utilize pressure vessels, piping, and tanks that operate over a wide range of temperatures and pressures. The materials of construction range from carbon steel to corrosion-resistant and heat-resistant alloys. Ensuring the safe and reliable operation of these facilities requires an effective asset integrity management program. This paper reviews the essential elements of an asset integrity management program and provides recommendations for judging the effectiveness of the program. The essential elements of an asset integrity management program include leadership, risk management, personnel and contractor competence, management of change, learning from events, emergency response, and implementation of quality assurance, maintenance, inspection, fitness-for-service assessment, repair, and replacement.
Management commitment to the program is a key factor in leadership. Risk is managed by mitigating the consequences of an incident as well as minimizing its likelihood; a robust risk-based inspection (RBI) program is typically part of the risk management. In-service degradation mechanisms of the materials that are used in pressure vessels, piping, and tanks include corrosion, fatigue, creep, and metallurgical embrittlement. If defects are identified by inspection, fitness for service assessment is performed to determine what action is to be taken. Training and certification of personnel and contractors is required to make sure that this work is properly performed. Incidents and near misses that occur in the plant and in the industry need to be reviewed to identify areas for potential program improvements. Timely and appropriate emergency response can minimize the consequences of an incident.