Inherent Safety Economic Index for Route Selection in Process Design at the Preliminary Design Stage

Process safety is a systematic approach for hazard and risk management in process design. This approach includes inherent, passive, active, and procedural strategies. Process design has many stages, and inherent safety is more prominent at the preliminary design stage as the main decisions are made here in the process industry. As the chemical industry continues to evolve, the need for an inherently safer process has become gradually important and a significant gap of the economic approach is found in the inherent safety concept. Therefore, a new indexing method using the relative ranking concept is consolidated in this work and named as inherent safety economic index (ISEI) that evaluates and ranks process routes based on process, chemical, equipment, and economic aspects. ISEI provides a comprehensive score for each process route considering the above-mentioned aspects. The suggested index has been used to evaluate four routes to produce methyl methacrylate. From the obtained results, it is recognized that the tertiary butyl alcohol process route has the lowest score of ISEI, indicating it is a comparatively safer and economical route. This technique would assist design engineers in making necessary and critical decisions about process route selection for process design at the preliminary design stage regarding safety and economic considerations.