Tower Overfill Hazard - A Program Approach to Reducing Risk

摘要

This paper describes a systematic program approach to reducing the risk of tower overfills in process units. This approach was taken on large project in a U.S. refinery which had embedded within its scope a program to reduce the risk due to tower overfill hazards. This program was tasked with analyzing and evaluating the risk due to tower overfills for 176 towers in over 25 operating units. This included consequence and severity identification, risk assessment, and identification of risk reduction means using Layer of Protection Analysis (LOPA) to reduce the tower overfill risk to the corporate risk reduction criteria. The program also identified the minimum tower instrumentation required for tower overfill protection. Each tower in the program was subject to a consequence based screening which identified and prioritized the towers for further analysis. Seven standard LOPA tower overfill scenarios were applied to each tower and project scope was identified based the LOPA recommendations.