|
|
|
Abstract Great changes in pore structure and quantity of coal may occur as the pyrolysis temperature rises. To study the change laws，a mercury intrusion method was adopted to measure and analyze the pore structure parameters of the solid products of flame coal pyrolysis，which were generated in vacuum system with temperatures from 300 ℃ to 600 ℃ and in high temperature steam state at 600 ℃；the pore fractal dimensions were calculated under different temperatures；and pore properties of solid products under two different pyrolysis ways were compared. The results indicate that：(1) Under conventional pyrolysis，the total pore volume and porosity of Heidaigou coal decreased from 300 ℃ to 400 ℃ and increased from 400 ℃ to 600 ℃；the increasing rate is the greatest from 500 ℃ to 600 ℃；the specific surface area increased progressively from 300 ℃ to 600 ℃. But for Zichang coal，the total pore volume and porosity increased from 300 ℃ to 400 ℃ and then decreased from 400 ℃ to 500 ℃ and increased from 500 ℃ to 600 ℃；the increasing rate is the greatest from 300 ℃ to 400 ℃；the specific surface area decreased progressively from 300℃ to 600 ℃. (2) Under conventional pyrolysis，large pores were the major parts of pore volume，micropore and transition pore were the major parts of the specific surface area. (3) Under high temperature steam pyrolysis，the large pores were the major parts of pore volume；the proportion of large pores of Zichang coal was 99.91%；micropores and transition pores were the major parts of the specific surface area of Heidaigou coal；the large pores were the major parts of specific surface area of Zichang coal. (4) Compared with conventional pyrolysis，the permeability of solid products of high temperature steam pyrolysis was greater；and compared with inert gas injection，it is the best method in the coal situ-pyrolysis application. These results can provide a scientific basis and theoretical guidance for the issue that coal pore structure changes with temperature during coal situ-pyrolysis.
|
|
Received: 19 March 2010
|
|
|
|
| [1] 胡耀青，赵阳升，杨 栋，等. 煤体的渗透性与裂隙分维的关系[J]. 岩石力学与工程学报，2002，21(10)：1 452–1 456.(HU Yaoqing，ZHAO Yangsheng，YANG Dong，et al. Relationship between permeability and fractal dimension of coal mass[J]. Chinese Journal of Rock Mechanics and Engineering，2002，21(10)：1 452–1 456.(in Chinese))
[2] 周 军，张 海，吕俊复，等. 高温下热解温度对煤焦孔隙结构的影响[J]. 燃料化学学报，2007，35(2)：155–159.(ZHOU Jun，ZHANG Hai，LU Junfu，et al. Effect of pyrolysis temperature on porous structure of anthracite chars produced at high temperatures[J]. Journal of Fuel Chemistry and Technology，2007，35(2)：155–159.(in Chinese))
[3] 许慎启，周志杰，杨 帆，等. 快速热解温度下的淮南煤焦与水蒸汽气化反应的研究[J]. 高校化学工程学报，2008，22(6)：947–953.(XU Shenqi，ZHOU Zhijie，YANG Fan，et al. Effects of pyrolysis temperature on steam gasification of Huainan char[J]. Journal of Chemical Engineering of Chinese Universities，2008，22(6)：947–953.(in Chinese))
[4] 何启林，王德明，陆 伟，等. 变温条件下煤结构与吸氧量的关系[J]. 煤炭学报，2007，32(8)：865–869.(HE Qilin，WANG Deming，LU Wei，et al. Relation between coal structure and absorbed oxygen at different temperatures[J]. Journal of China Coal Society，2007，32(8)：865–869.(in Chinese))
[5] 李荣西，金奎励，杨友运. 煤源岩孔隙演化与煤成油气初次运移研究[J]. 中国煤田地质，1998，10(1)：1–4.(LI Rongxi，JIN Kuili，YANG Youyun. The inital migration of the hydrocarbon from the coal and the porous texture of the coal as source rocks[J]. Coal Geology of China，1998，10(1)：1–4.(in Chinese))
[6] 王明敏，张建胜，张守玉，等. 热解条件对煤焦比表面积及孔隙分布的影响[J]. 煤炭学报，2008，33(1)：76–79.(WANG Mingmin，ZHANG Jiansheng，ZHANG Shouyu，et al. Effect of pyrolysis conditions on the char surface area and pore distribution[J]. Journal of China Coal Society，2008，33(1)：76–79.(in Chinese))
[7] 张玉涛，王德明，仲晓星. 煤孔隙分形特征及其随温度的变化规律[J]. 煤炭科学技术，2007，35(11)：73–76.(ZHANG Yutao，WANG Deming，ZHONG Xiaoxing. Features of fissure sharp in coal borehole and variation law with temperature[J]. Coal Science and Technology，2007，35(11)：73–76.(in Chinese))
[8] 杨海平，陈汉平，鞠付栋，等. 典型煤种加压热解与气化试验研究[J]. 中国电机工程学报，2007，27(26)：18–22.(YANG Haiping，CHEN Hanping，JU Fudong，et al. Study on pressurized pyrolysis and gasification of Chinese typical coal samples[J]. Proceedings of the CSEE，2007，27(26)：18–22.(in Chinese))
[9] 王俊琪，方梦祥，骆仲泱，等. 热解半焦孔隙特性研究[J]. 热力发电，2008，37(7)：6–9.(WANG Junqi，FANG Mengxiang，LUO Zhongyang，et al. Study on porous characters of pyrolyzed carbocoal[J]. Thermal Power Generation，2008，37(7)：6–9.(in Chinese))
[10] 平传娟，周俊虎，程 军，等. 混煤热解过程中的表面形态[J]. 化工学报，2007，58(7)：1 798–1 804.(PING Chuanjuan，ZHOU Junhu，CHENG Jun，et al. Surface structure of blended coals during pyrolysis[J]. Journal of Chemical Industry and Engineering(China)，2007，58(7)：1 798–1 804.(in Chinese))
[11] 刘 辉，吴少华，孙 锐，等. 快速热解褐煤焦的比表面积及孔隙结构[J]. 中国电机工程学报，2005，25(12)：86–90.(LIU Hui，WU Shaohua，SUN Rui，et al. Specific area and pore structure of lignite char under the condition of fast pyrolysis[J]. Proceedings of the CSEE，2005，25(12)：86–90.(in Chinese))
[12] 王明敏，张建胜，张守玉，等. 热解条件对煤焦结构及气化反应活性的影响[J]. 煤炭转化，2007，30(3)：21–24.(WANG Mingmin，ZHANG Jiansheng，ZHANG Shouyu，et al. Effect of pyrolysis conditions on the structure and gasification reactivity of char[J]. Coal Conversion，2007，30(3)：21–24.(in Chinese))
[13] 刘铁峰，房倚天，王 洋. 煤高温快速热解规律研究[J]. 燃料化学学报，2009，37(1)：20–25.(LIU Tiefeng，FANG Yitian，WANG Yang. Rapid pyrolysis of coal at high temperature[J]. Journal of Fuel Chemistry and Technology，2009，37(1)：20–25.(in Chinese))
[14] 李文军，罗娟娟，梁新星，等. 煤炭地下气化过程中半焦孔隙结构的变化规律[J]. 煤炭转化，2009，32(2)：10–13.(LI Wenjun，LUO Juanjuan，LIANG Xinxing，et al. Rule of porous structure of semi-coke in the underground coal gasification[J]. Coal Conversion，2009，32(2)：10–13.(in Chinese))
[15] 王晓亮，何 榕，陈永利. 煤颗粒热解过程中孔隙分形维数变化的数值模拟[J]. 清华大学学报(自然科学版)，2008，48(2)：244–247.(WANG Xiaoliang，HE Rong，CHEN Yongli. Numerical simulation of pore fractal dimension evolution during coal pyrolysis[J]. Journal of Tsinghua University(Science and Technology)，2008，48(2)：244–247.(in Chinese))
[16] 谢克昌. 煤的结构与反应性[M]. 北京：科学出版社，2002.(XIE Kechang. Coal structure and its reactivity[M]. Beijing：Science Press，2002.(in Chinese))
[17] CARLOS A，LEON Y L. New perspectives in mercury porosimetry[J]. Advances in Colloid and Interface Science，1998，76–77：341–372.
[18] GREGG S J，SING K S W．Adsorption，surface area and porosity[M]．London：Academic Press，1982． |
| [1] |
LI Botao1, 2, 3, TAN Yuxuan1, LIN Haifei4, 5*, WEI Jianping1, 2, 3, ZHANG Hongtu1, 2, 3, LI Shugang4, 5, WEI Zongyong4, 5, WANG Pei4, LUO Rongwei4, LIU Yanwei1, 2, 3. Mechanical properties and mesoscopic damage evolution of coal under liquid-nitrogen freezing at different initial temperatures[J]. , 2026, 45(6): 1757-1772. |
|
|
|
