1. Thermal behavior and microcharacterization analysis of second-oxidized coal.
- Author
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Deng, Jun, Zhao, Jing-Yu, Huang, An-Chi, Zhang, Yan-Ni, Wang, Cai-Ping, and Shu, Chi-Min
- Subjects
COAL ,OXIDIZING agents ,COAL mining ,COALBED methane ,COAL combustion ,FOURIER transform spectroscopy ,THERMAL properties - Abstract
Among coal-producing countries, China has witnessed the highest frequency and severity of coal fires. During mining in the re-mining face and the lower part of the thick coal seam (or coal seam group), second or multiple oxidations of the residual coal can readily occur in mined-out areas, severely increasing the risk of coal fires. The study of multiple oxidations of coal aids in the early detection of spontaneous combustion of remaining coal in the mined-out areas. The characteristics of coal fires are demonstrated using fresh coal samples (first-oxidized coal) and oxidized coal samples (second-oxidized coal) from four different ranks of coals. Proximate and elemental analysis, Fourier transform spectroscopy, and thermogravimetry-differential scanning calorimetry were adopted to investigate the quality, microcharacteristics, characteristic temperatures, and apparent activation energy of second-oxidized coal. In addition, the effect of spontaneous combustion at heating rates of 5.0, 10.0, and 15.0 °C min was studied. Compared with the four samples of first-oxidized coal, those of second-oxidized coals cause fire easily under the same conditions. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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