Theoretical and numerical study on ignition behaviour of coal dust layers on a hot surface with corrected kinetic parameters
- Industrial fires and explosions initiating from self-ignition of combustible porous dust deposits represent a serious hazard for human beings, environment and industry. Understanding the fundamental basis of combustible dust ignition behaviours at different geometries is of importance to prevent and mitigate the accidental risks. A correlation of self-ignition temperatures (SITs) measured by hot-oven tests and minimum ignition temperatures of dust layers (MITLs) determined by hot-plate tests has been established previously. However, this analogy approach based on Frank-Kamenetzkii model is limited by ignoring the influence of oxygen diffusion. In this work, an improved method is developed by implementing a correction factor for the pre-exponential factor caused by the boundary geometry. This method is testified by comparing with experimental data, previous analogy method and numerical simulation. Results show that our proposed method performs a better predictability of MITLs andIndustrial fires and explosions initiating from self-ignition of combustible porous dust deposits represent a serious hazard for human beings, environment and industry. Understanding the fundamental basis of combustible dust ignition behaviours at different geometries is of importance to prevent and mitigate the accidental risks. A correlation of self-ignition temperatures (SITs) measured by hot-oven tests and minimum ignition temperatures of dust layers (MITLs) determined by hot-plate tests has been established previously. However, this analogy approach based on Frank-Kamenetzkii model is limited by ignoring the influence of oxygen diffusion. In this work, an improved method is developed by implementing a correction factor for the pre-exponential factor caused by the boundary geometry. This method is testified by comparing with experimental data, previous analogy method and numerical simulation. Results show that our proposed method performs a better predictability of MITLs and simplicity. The improved analogy method indicates that the different boundary geometries of a dust deposit significantly impact the apparent pre-exponential factor, while have an ignorable influence on the activation energy, which is also verified by numerical investigations. Furthermore, the numerical model with the corrected kinetic parameters provides a satisfactory explanation compared with experimental observations regarding to temperature and concentration evolutions of dust layers.…
Autor*innen: | Martin Schmidt, D. Wu, Z. Song, Q. Zhang, X. Qian |
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Dokumenttyp: | Zeitschriftenartikel |
Veröffentlichungsform: | Verlagsliteratur |
Sprache: | Englisch |
Titel des übergeordneten Werkes (Englisch): | Journal of Hazardous Materials |
Jahr der Erstveröffentlichung: | 2019 |
Organisationseinheit der BAM: | 2 Prozess- und Anlagensicherheit |
2 Prozess- und Anlagensicherheit / 2.1 Sicherheit von Energieträgern | |
Verlag: | Elsevier |
Jahrgang/Band: | 368 |
Erste Seite: | 156 |
Letzte Seite: | 162 |
DDC-Klassifikation: | Technik, Medizin, angewandte Wissenschaften / Ingenieurwissenschaften / Ingenieurbau |
Freie Schlagwörter: | Dust layers; Minimum ignition temperature; Self-ignition; Spontanious ignition |
Themenfelder/Aktivitätsfelder der BAM: | Infrastruktur |
Infrastruktur / Fire Science | |
DOI: | 10.1016/j.jhazmat.2019.01.032 |
Verfügbarkeit des Dokuments: | Datei im Netzwerk der BAM verfügbar ("Closed Access") |
Datum der Freischaltung: | 24.04.2019 |
Referierte Publikation: | Ja |
Datum der Eintragung als referierte Publikation: | 24.04.2019 |