Safe Process Start-up Procedures Based on an Operator Training Simulator: a Case Study

Process systems engineering is rapidly moving from steady state simulation towards operator training simulation, based on dynamic models, automated procedures, and predictive systems. Conventional operating conditions are well-known and easily controlled by field operators as well as control-room operators, whereas other situations are still not. This is the case of more unusual circumstances, such as plant start-ups as well as emergency shutdowns. The implementation of detailed dynamic mathematical models allows simulating the behavior of single process units as well as whole industrial plants, with the possibility to study unusual scenarios, especially for two reasons: first of all, it is necessary to train the operator and prepare him/her to face with distinct events. Secondly, there is the need for evaluating the best automatic procedure to manage either unconventional or critical situations, without waiting for them to occur. In this sense, the safety approach is changing from reacting to predicting. The paper investigates and compares different procedures to regulate process transients, described by a sequence of actions. The main objective is to improve the process start-up reliability as well as the plant safety. The manuscript discusses the simulation of a propane/butane splitter