Danko M., Janosovsky J., Labovsky J., Labovska Z., Jelemensky L., 2018, Use of LOPA Concept to Support Automated Simulation-Based HAZOP Study, Chemical Engineering Transactions, 67, 283-288.
This paper discusses the relation between hazard and operability study – HAZOP, mathematical modeling of processes and process control presented as the first layer of protection within general Layer of protection analysis (LOPA). In this work, these aspects are integrated in a new concept of hazard identification and operability study of the investigated process and both, steady state and dynamic, analyses are integrated in the methodology. The concept is able to identify hazardous regimes caused by parameter disturbances itself and also those when inappropriate control loop actions act synergic with already present disturbances. Thus, validation of the applied process control is provided. The concept is applied for the CSTR chemical process of catalyzed propylene glycol production under Proportional-Integral-Derivative (PID) actions. Under the investigated conditions, the process is characterized by the presence of strong nonlinearity and multiple steady state phenomena, which unpredictably affect the process control actions. Some hazardous events and operability issues were identified by the presented methodology and corrective actions were proposed.
