Ignition temperature and mechanism of carbonaceous dust clouds: The roles of volatile matter, CH4 addition, O2 mole fraction and diluent gas
- Minimum ignition temperature of dust clouds (MITC) was studied experimentally and theoretically in different atmospheres. Three carbonaceous dusts were tested in both air and O2/CO2 atmospheres with CH4 mole fraction from 0 to 2%. Results showed that the ignition risk of the three dusts significantly increases (decrease of MITC by ~100 ℃) with increasing XO2 from 21% to 50%, but significantly decreases replacing N2 in air with CO2. The inhibition effect of CO2 on MITCs could be diminished by increasing XO2 or adding CH4. The addition of small amount of CH4 has different effects on the MITCs of different dust samples, following the opposite order of volatile matter content: anthracite>bituminous coal>starch. Two modified steady-state ignition models, considering the density of mixture gas and dust cloud, XO2 and its diffusivity, were developed to interpret the experimental observations. The analysis revealed that the global heterogeneous ignition model suits well for the hybrid mixturesMinimum ignition temperature of dust clouds (MITC) was studied experimentally and theoretically in different atmospheres. Three carbonaceous dusts were tested in both air and O2/CO2 atmospheres with CH4 mole fraction from 0 to 2%. Results showed that the ignition risk of the three dusts significantly increases (decrease of MITC by ~100 ℃) with increasing XO2 from 21% to 50%, but significantly decreases replacing N2 in air with CO2. The inhibition effect of CO2 on MITCs could be diminished by increasing XO2 or adding CH4. The addition of small amount of CH4 has different effects on the MITCs of different dust samples, following the opposite order of volatile matter content: anthracite>bituminous coal>starch. Two modified steady-state ignition models, considering the density of mixture gas and dust cloud, XO2 and its diffusivity, were developed to interpret the experimental observations. The analysis revealed that the global heterogeneous ignition model suits well for the hybrid mixtures of anthracite or bituminous coal dusts. In contrast, the proposed global homogeneous ignition model was found to be only valid for the pure starch dust, and the extra CH4 addition could strongly affect the ignition process of starch, particularly in O2/CO2 atmospheres with higher XO2.…
Autor*innen: | Dejian WuORCiD, X. Tan, A. Wei, Q. Duan, W. Huang, Martin Schmidt |
---|---|
Dokumenttyp: | Zeitschriftenartikel |
Veröffentlichungsform: | Verlagsliteratur |
Sprache: | Englisch |
Titel des übergeordneten Werkes (Englisch): | Journal of hazardous materials |
Jahr der Erstveröffentlichung: | 2021 |
Organisationseinheit der BAM: | 2 Prozess- und Anlagensicherheit |
2 Prozess- und Anlagensicherheit / 2.1 Sicherheit von Energieträgern | |
Verlag: | Elsevier |
Verlagsort: | Amsterdam |
Jahrgang/Band: | 405 |
Aufsatznummer: | 124189 |
Erste Seite: | 1 |
Letzte Seite: | 10 |
DDC-Klassifikation: | Technik, Medizin, angewandte Wissenschaften / Ingenieurwissenschaften / Ingenieurbau |
Freie Schlagwörter: | Dust explosions; Gas explosions; Hybrid mixtures; Minimum ignition temperature |
Themenfelder/Aktivitätsfelder der BAM: | Infrastruktur |
Infrastruktur / Fire Science | |
DOI: | 10.1016/j.jhazmat.2020.124189 |
ISSN: | 0304-3894 |
ISSN: | 1873-3336 |
Verfügbarkeit des Dokuments: | Datei im Netzwerk der BAM verfügbar ("Closed Access") |
Datum der Freischaltung: | 26.11.2021 |
Referierte Publikation: | Ja |
Datum der Eintragung als referierte Publikation: | 26.11.2021 |