Development of a general inherent safety assessment tool at early design stage of chemical process

Abstract

The purpose of process safety is the prevention and mitigation of incidents arising from process-related hazards while inherent safety design is one of the most effective ways to prevent accidents in the process safety management. Inherent safety assessment tools (ISATs) play an important role in the application of inherent safety design. However, many ISATs suffer from various limitations. Hence, we propose a general inherent safety assessment tool to evaluate inherent safety level at the early design stage of chemical process. First, we define two criteria of good inherent safety assessment tools from their purpose, namely reliability and usability. We link the inherent consequence to process parameter and chemical property, subsequently propose a general inherent safety assessment tool for different hazardous sources (e.g., and fire/ explosion, health, environment). The proposed tool can eliminate the uncertainties in the risk-based inherent safety assessment tools and address the problem that the amount of material handled is not considered in the continuous numerical assessment tools. Finally, we use two cases to illustrate the proposed inherent safety assessment tool and compare with the commonly used ISATs. This work can accelerate the inherent safety design at the early design stage to prevent incidents in the chemical process.