Risk-Based Inspection Analysis for High Pressure Hydrogenation Cracking Unit Available to Purchase

High pressure hydrogenation cracking unit is the core equipment system in the aromatic plant, which is subjected simultaneously to the action of hydrogen and high pressure and high temperature. In this paper, quantitative analysis method of RBI was carried out by Orbit-Onshore software, which was developed by DNV corporation. In API 581, the risk situation for a certain equipment unit were classified into four grades, such as low risk grade and medium risk grade and medium-high risk grade and high grade, which is expressed as risk matrix. The whole risk distribution of 553 equipment and piping items was obtained, and in which the hydrocracking reactors and the reactor effluent air coolers are belong to ‘medium-high risk’ grade. Based on the RBI results, an optimum inspection plan was developed by the author to reduce the risk level for the hydrogenation cracking unit. It is concluded that the optimum inspection plan was completely satisfied with the engineering specification of the aromatic plant, after the validation of the inspection activity in 2004.