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Since the early 1990s, considerable efforts have been made in researching and applying approaches for faults detection and diagnosis in chemical processes. The occurrence of chemical accidental events due to thermal runaways has serious consequences for the human, environmental and economic and encourage these efforts. This is the main motivation for this paper that details a fault detection and diagnosis approach for exothermic reactions. The proposed approach is based on the temperature measurements. It compares the collected measurements with a reference behavior for early thermal runaway detection. Once a fault is detected, characteristic features are extracted from the successive measurements collected within a time window. The fault isolation is based on a classification of these features with respect to several faulty modes. The studied faults are the most responsible for thermal runaway events. A multiset of linear classifiers and binary decision diagrams indexed with respect to the time are used for that purpose. The synthesis of peroxyformic acid in a batch reactor is considered to validate the proposed method by numerical simulations and experiments. The performance of the proposed method is carried out in a systematic way in order to evaluate its robustness and efficiency.

Over the past decades, serious industrial events affecting lives, facilities and environment have occurred in chemical industry. Among the most critical events are the phenomena of thermal runaway that often lead to important damages. The rapid detection of thermal runaway events and the isolation of the most probable cause are major challenges to ensure safe operations. The objective of this work is to propose a method for early detection of faults in a chemical reactor based on a reference model and for isolating the fault cause. The reaction of perhydrolysis of formic acid to peroxyformic acid by hydrogen peroxide is used as a test case. The kinetic model of the reaction was computed in order to simulate the reaction in normal and abnormal modes. In a first stage, the method was validated by simulation data and an experimental validation is now in progress. As a consequence, the proposed method can contribute to the safety of chemical reactors in the chemical industry.

Accidental events in chemical industry can cause damages to human health, environment and economy. To prevent such events in industries, it is essential to identify and analyze the past events. To the best of our knowledge, such an analysis has not been done for the French chemical industry sector, which is the second producer in Europe. To fill this gap, 169 events were selected and collected in the French database ARIA (Analysis, Research and Information on Accidents). These events occurred between 1974 and 2014. The causes and consequences of the events were analyzed. The study shows that the causes were mainly related to operator errors. Then, a semi-quantitative analysis of risk was also carried out, based on the frequencies and consequences of the events. This analysis confirms that chemical industry activities present a significant risk. Based on this analysis, national agencies can make some recommendations or rules in order to reduce the number of events in chemical industry.

The thermal safety of chemical processes requires knowledge of the safety parameters that quantify the probability, such as time to maximum rate under adiabatic conditions (TMRad), and the severity, such as adiabatic temperature rise under adiabatic conditions (ΔTad). The zero-order approximation is used to ease the determination of TMRad values at different process temperatures; but how can one be sure that this approximation is acceptable, compared to the use of an intrinsic kinetic model? In the literature, there are no such studies that compare the values of TMRad by using zero-order and intrinsic kinetic models. For that, decomposition of hydrogen peroxide in the presence (and in the absence) of copper sulfate was studied in an advanced reactive system screening tool (ARSST) unit. This calorimeter operates under near-adiabatic conditions, based on heat loss compensation principle, and by using a background heating rate (β). In a first stage, a kinetic model was built to estimate the intrinsic kinetic...