个人信息Personal Information
教授
博士生导师
硕士生导师
主要任职:学科建设办公室主任(校学术委员会办公室主任、一流大学建设办公室主任)
性别:男
毕业院校:东京大学
学位:博士
所在单位:化工学院
学科:安全科学与工程. 化工过程机械
办公地点:化工学院实验楼H505
联系方式:0411-84986501
电子邮箱:gaoweidlut@dlut.edu.cn
Effect of pyrolysis and oxidation characteristics on lauric acid and stearic acid dust explosion hazards
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论文类型:期刊论文
发表时间:2020-01-01
发表刊物:JOURNAL OF LOSS PREVENTION IN THE PROCESS INDUSTRIES
收录刊物:EI、SCIE
卷号:63
ISSN号:0950-4230
关键字:Dust explosion; Thermal pyrolysis oxidation; Apparent activation energy; Pre-exponential factor; Explosion sensitivity; Explosion severity
摘要:The effect of pyrolysis and oxidation characteristics on the explosion sensitivity and severity parameters, including the minimum ignition energy MIE, minimum ignition temperature MIT, minimum explosion concentration MEC, maximum explosion pressure P-max maximum rate of pressure rise (dP/dt)(max) and deflagration index K-st, of lauric acid and stearic acid dust clouds was experimentally investigated. A synchronous thermal analyser was used to test the particle thermal characteristics. The functional test apparatuses including the 1.2 L Hartmann-tube apparatus, modified Godbert-Greenwald furnace, and 20 L explosion apparatus were used to test the explosion parameters. The results indicated that the rapid and slow weight loss processes of lauric acid dust followed a one-dimensional diffusion model (Dl model) and a 1.5 order chemical reaction model (F1.5 model), respectively. In addition, the rapid and slow weight loss processes of stearic acid followed a 1.5 order chemical reaction model (F1.5 model) and a three-dimensional diffusion model (D3 model), respectively, and the corresponding average apparent activation energy E and pre-exponential factor A were larger than those of lauric acid. The stearic acid dust explosion had higher values of MIE and MIT, which were mainly dependent on the higher pyrolysis and oxidation temperatures and the larger apparent activation energy E determining the slower rate of chemical bond breakage during pyrolysis and oxidation. In contrast, the lauric acid dust explosion had a higher MEC related to a smaller pre-exponential factor A with a lower amount of released reaction heat and a lower heat release rate during pyrolysis and oxidation. Additionally, due to the competition regime of the higher oxidation reaction heat release and greater consumption of oxygen during explosion, the explosion pressure P-m of the stearic acid dust was larger in low concentration ranges and decayed to an even smaller pressure than with lauric acid when the concentration exceeded 500 g/m(3). The rate of explosion pressure rise (dP/dr)(m) of the stearic acid dust was always larger in the experimental concentration range. The stearic acid dust explosion possessed a higher P-max, (dP/dt)(max) and K-st mainly because of a larger pre-exponential factor A related to more active sites participating in the pyrolysis and oxidation reaction. Consequently, the active chemical reaction occurred more violently, and the temperature and overpressure rose faster, indicating a higher explosion hazard class for stearic acid dust.