Thermal properties of coals with different metamorphic levels in air atmosphere

被引：40
作者：
Deng, Jun [1 ,2 ]
Ren, Shuai-Jing [1 ]
Xiao, Yang [1 ,2 ]
Li, Qing-Wei [1 ]
Shu, Chi-Min [3 ]
机构：
[1] Xian Univ Sci & Technol, Sch Safety Sci & Engn, 58 Yanta Middle Rd, Xian 710054, Shaanxi, Peoples R China
[2] Shaanxi Key Lab Prevent & Control Coal Fire, 58 Yanta Middle Rd, Xian 710054, Shaanxi, Peoples R China
[3] Natl Yunlin Univ Sci & Technol, Grad Sch Engn Sci & Technol, 123 Univ Rd,Sect 3, Touliu 64002, Yunlin, Taiwan
来源：
APPLIED THERMAL ENGINEERING | 2018年 / 143卷
基金：
中国国家自然科学基金; 中国博士后科学基金;
关键词：
Heat transfer; Crystallinity; Thermal diffusivity; Specific heat; Thermal conductivity; TRANSPORT-PROPERTIES; HIGH-TEMPERATURE; SPONTANEOUS COMBUSTION; HEAT-CAPACITY; FLASH METHOD; CONDUCTIVITY; DIFFUSIVITY; ROCKS; DEPENDENCE; CRYSTALS;
D O I：
10.1016/j.applthermaleng.2018.07.117
中图分类号：
O414.1 [热力学];
学科分类号：
摘要：
Thermal properties of coal are crucial in the heat-transfer process of its spontaneous combustion. Thermophysical properties of four metamorphic-grade coal samples were investigated in air using a laser-flash apparatus. Their crystallinities were analyzed by X-ray diffractometry. The results indicated that the trend in thermal diffusivity was opposite to that of crystallinity. As the temperature increased, thermal diffusivity first decreased and then increased; specific heat first increased and then decreased. With the exception of the meager lean coal sample, the trend of thermal conductivity as a function of temperature agreed with that of specific heat. As the metamorphic grade of the samples increased, the thermal diffusivity minimum and specific heat maximum shifted toward higher temperatures; in contrast, the minimum thermal conductivity shifted toward lower temperatures. From these trends, it was possible to recognize different temperature ranges according to how different properties (thermal conductivity, thermal diffusivity, specific heat, and metamorphism grade) influenced each other.
引用
收藏
页码：542 / 549
页数：8
相关论文
共 36 条
[21]  
ISO GUM, 2008, ISO IEC GUID UNC M 3
[22]   Changes in spontaneous combustion characteristics of low-rank coal through pre-oxidation at low temperatures [J].
Jo, Wantaek ;
Choi, Hokyung ;
Kim, Sangdo ;
Yoo, Jiho ;
Chun, Donghyuk ;
Rhim, Youngjoon ;
Lim, Jeonghwan ;
Lee, Sihyun .
KOREAN JOURNAL OF CHEMICAL ENGINEERING, 2015, 32 (02) :255-260
[23]   Thermal conductivity accumulation in amorphous silica and amorphous silicon [J].
Larkin, Jason M. ;
McGaughey, Alan J. H. .
PHYSICAL REVIEW B, 2014, 89 (14)
[24]   Thermal transport properties of major Archean rock types to high temperature and implications for cratonic geotherms [J].
Merriman, Jesse D. ;
Whittington, Alan G. ;
Hofmeister, Anne M. ;
Nabelek, Peter I. ;
Benn, Keith .
PRECAMBRIAN RESEARCH, 2013, 233 :358-372
[25]   Temperature dependence of thermal diffusivity, specific heat capacity, and thermal conductivity for several types of rocks [J].
Miao, S. Q. ;
Li, H. P. ;
Chen, G. .
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY, 2014, 115 (02) :1057-1063
[26]   Effect of water saturation on rock thermal conductivity measurements [J].
Nagaraju, P. ;
Roy, Sukanta .
TECTONOPHYSICS, 2014, 626 :137-143
[27]   FLASH METHOD OF DETERMINING THERMAL DIFFUSIVITY, HEAT CAPACITY, AND THERMAL CONDUCTIVITY [J].
PARKER, WJ ;
JENKINS, RJ ;
ABBOTT, GL ;
BUTLER, CP .
JOURNAL OF APPLIED PHYSICS, 1961, 32 (09) :1679-&
[28]   Transport properties of low-sanidine single-crystals, glasses and melts at high temperature [J].
Pertermann, Maik ;
Whittington, Alan G. ;
Hofmeister, Anne M. ;
Spera, Frank J. ;
Zayak, John .
CONTRIBUTIONS TO MINERALOGY AND PETROLOGY, 2008, 155 (06) :689-702
[29]   Thermal diffusivity of olivine-group minerals at high temperature [J].
Pertermann, Maik ;
Hofmeister, Anne M. .
AMERICAN MINERALOGIST, 2006, 91 (11-12) :1747-1760
[30]   Temperature dependence of thermal transport properties of crystalline rocks - a general law [J].
Seipold, U .
TECTONOPHYSICS, 1998, 291 (1-4) :161-171
1234