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Ignition Characteristics for Thermal Runaways of Hazard Chemical Reactions of Different Degree of Reactions

Saad A. El-Sayed

Abstract


Thermal explosion characteristics of a hazardous chemical reaction of different reaction order have been investigated analytically and numerically for both Arrhenius and Frank-Kamenetskii approximation models for the rate of reaction. The critical conditions in the temperature-time, concentration-time, and temperature – concentration planes of solutions are presented. A comparison between the results of analytical solutions in these planes is offered. The solutions show that the critical states in the temperature-time plane are, in fact, subcritical states (non-ignition) in the concentration-time and temperature –concentration planes. The effect of initial and ambient temperatures, exothermicity, heat transfer, etc. on the critical conditions is investigated. It is also shown that changing these parameters alter the behavior of a system from safe to unsafe mode and vice versa. All trajectories of numerical solutions in the different planes are presented and clearly discussed. Keywords: Thermal explosion, critical conditions, hazard chemical reaction, safe handling of hazard materials

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References


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