PREVENTIVE AND PREDICTIVE MAINTENANCE OF AMMONIUM NITRATE GRANULATION PROCESS BASED ON PRELIMINARY HAZARD ANALYSIS TECHNIQUE

A technological accident in a fertilizer production plant often results from the interaction between several hazards. Preliminary Hazard Analysis (PHA) being a general level, qualitative method, it is easily applicable for all types of operations and functions of a system. The objective of this paper is to demonstrate the importance of using PHA in the context of preventive and predictive maintenance, and to highlight the potential benefits of these strategies in mitigating the risks of potential accidents related to the granulation process of fertilizer grade AN. The results of the study show that the most dangerous scenarios identified, in terms of consequences, are potential explosions of AN due to friction and melting in case of rotative equipment failure, or auto-decomposition and explosion of AN due to contamination with organic substances. Since qualitative deterministic approaches are lacking in uncertainty and sensitivity analysis, their use should be completed by more complex quantitative analyses, in order to support efficient decision making for risk mitigation and balanced maintenance efforts.