Design of sustainable chemical processes incorporating the principles of inherent safety

Abstract

Nowadays, the incorporation of safety concepts in the design of chemical plants, together the economic criterion, is a priority within the area of process systems engineering. An inherently safer chemical process avoids or reduces the hazards, rather than managing by adding layers of protection with safety devices. In this work, a systematic methodology is proposed for obtaining the optimal operation conditions that simultaneously seek for the minimization of the inherently safer index and the total annualized cost. This approach is applied to the case study of a styrene monomer production plant. The performance of some units of this plant have been rigorously analyzed using process simulators to obtain simplified models suitable for gradient-based optimization. These surrogated models together short-cut models for the remaining units define a nonlinear programing (NLP) model, which has been solved using the state-of-the-art NLP solvers. The results provide the optimal design and its operation conditions which minimize the risks and hazards of a chemical accident, and besides, takes into account the economic criterion.