Application of an enhanced RBI method for petrochemical equipments

The American Petroleum Institute guideline provides a methodology for calculating the risks of equipments installed in refineries or petrochemical plants. However, especially in connection with consequence analysis, there are limitations of its direct application to petrochemical plant. As a principal cause, only representative material is recommended for the risk evaluation while the equipment contains numerous materials. The objectives of this paper are to propose an enhanced risk-based inspection (RBI) method to resolve above shortcomings and to assess the risks of typical petrochemical equipments. In this respect, a RBI program including a material management database is developed to fully incorporate the characteristics of different materials. The proposed program consists of qualitative, semi-quantitative, and quantitative evaluation modules in which representative material, as well as toxic materials, is selected automatically for comparison to those getting from the current guideline. It has been applied to assess the risks of major equipments in ethylene facility such as vessel and column. Thereby, realistic evaluation results were obtained and applicability of the proposed RBI program was proven. [DOI: 10.1115/1.2218350] Keywords: mole fraction, petrochemical equipment, qualitative approach, quantitative approach, risk-based inspection