Application Research On Inherent Safety Method in Chemical Process Safety Design

Abstract：Conventional process safety design techniques were used to identify potential hazards and suggested corresponding solutions. Nevertheless, the recommend risk reduction alternatives against application of inherent safety design (ISD) concept to prevent or minimize the inherent hazards. One of the main reasons could be the shortage of reasonable techniques or tools to support implementation of the guidewords in process safety design. Thus, a risk-based procedure was conducted to analyze the performance of various inherent safety principles in chemical process. The developed method namely Reformulate Inherently Safer Idea (RISI) could be used to quantitative analysis the hazard and inherent safety degree based on the hazard characteristics of the exothermic reaction and thermal runaway risk assessment theory. Under the condition of the thermal effect of the reaction were more considered, the potential of thermal runaway was represented for the trigger conditions and the power were represented the severity of the accident, then the potential hazards of process was obtained. If the hazard was unaccepted, the inherently safer design must be taken and the inherent safe impact value was calculated. RISI was applied to a nitric acid oxidation of alcohols combined with the experimental data by RC1. The results show that the potential hazard value was reduced by 60% after ISD. Meanwhile, it was found that the sensitivity of RISI to basic process parameters was higher than SWeHI and I2SI index.

Key words：Inherent safe; Inherent safer design; Hazardous reaction; Hazard assessment; Risk analysis